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1

Evidence of Differential HLA Class I-Mediated Viral Evolution in Functional and Accessory/Regulatory Genes of HIV-1  

PubMed Central

Despite the formidable mutational capacity and sequence diversity of HIV-1, evidence suggests that viral evolution in response to specific selective pressures follows generally predictable mutational pathways. Population-based analyses of clinically derived HIV sequences may be used to identify immune escape mutations in viral genes; however, prior attempts to identify such mutations have been complicated by the inability to discriminate active immune selection from virus founder effects. Furthermore, the association between mutations arising under in vivo immune selection and disease progression for highly variable pathogens such as HIV-1 remains incompletely understood. We applied a viral lineage-corrected analytical method to investigate HLA class I-associated sequence imprinting in HIV protease, reverse transcriptase (RT), Vpr, and Nef in a large cohort of chronically infected, antiretrovirally naïve individuals. A total of 478 unique HLA-associated polymorphisms were observed and organized into a series of “escape maps,” which identify known and putative cytotoxic T lymphocyte (CTL) epitopes under selection pressure in vivo. Our data indicate that pathways to immune escape are predictable based on host HLA class I profile, and that epitope anchor residues are not the preferred sites of CTL escape. Results reveal differential contributions of immune imprinting to viral gene diversity, with Nef exhibiting far greater evidence for HLA class I-mediated selection compared to other genes. Moreover, these data reveal a significant, dose-dependent inverse correlation between HLA-associated polymorphisms and HIV disease stage as estimated by CD4+ T cell count. Identification of specific sites and patterns of HLA-associated polymorphisms across HIV protease, RT, Vpr, and Nef illuminates regions of the genes encoding these products under active immune selection pressure in vivo. The high density of HLA-associated polymorphisms in Nef compared to other genes investigated indicates differential HLA class I-driven evolution in different viral genes. The relationship between HLA class I-associated polymorphisms and lower CD4+ cell count suggests that immune escape correlates with disease status, supporting an essential role of maintenance of effective CTL responses in immune control of HIV-1. The design of preventative and therapeutic CTL-based vaccine approaches could incorporate information on predictable escape pathways. PMID:17616974

Brumme, Zabrina L; Brumme, Chanson J; Heckerman, David; Korber, Bette T; Daniels, Marcus; Carlson, Jonathan; Kadie, Carl; Bhattacharya, Tanmoy; Chui, Celia; Szinger, James; Mo, Theresa; Hogg, Robert S; Montaner, Julio S. G; Frahm, Nicole; Brander, Christian; Walker, Bruce D; Harrigan, P. Richard

2007-01-01

2

Regulation of T-cell differentiation by CD2 and CD28 accessory molecules.  

PubMed Central

It was analysed to what extent the functional T-cell responses that result from T-cell receptor (TcR)/CD3 triggering differ from responses that are induced after simultaneous ligation of CD2 and CD28 accessory molecules. To allow a quantitative comparison of these activation pathways, purified lymphocytes were stimulated with either graded densities of immobilized anti-CD3 monoclonal antibodies (mAb) or with increasing amounts of anti-CD28 mAb in the presence of a constant concentration of anti-CD2 mAb. Both activation systems were sensitive to the regulatory properties of CD11a/CD18 molecules. T-cell stimulation via CD2/CD28 molecules induced a more potent release of interleukin-2 (IL-2) and more pronounced T helper (Th) cell responses than T-cell stimulation via the TcR/CD3 complex, whereas CD25 expression was more readily initiated after T-cell activation via the TcR/CD3 complex. Optimal Th cell differentiation was detected under conditions of suboptimal receptor occupancy whereas, in contrast, optimal cytolytic T lymphocyte (CTL) differentiation required optimal TcR/CD3 or CD2/CD28 engagement. The findings indicate that T-cell differentiation can be influenced in a qualitative manner by the strength of the activation signal provided, and suggest that antigen-specific T-cell responses might be regulated in a quantitative manner through CD2 and CD28 accessory molecules. PMID:1684171

de Jong, R; Stokkers, P; Lamme, E; Kool, J M; Borst, F; Brouwer, M; Miedema, F; van Lier, R A

1991-01-01

3

Differentially Transcendental Functions  

E-print Network

The aim of this paper is to exhibit a method for proving that certain analytic functions are not solutions of algebraic differential equations. The method is based on model-theoretic properties of differential fields and properties of certain known transcendental differential functions, as of $\\Gamma(x)$. Furthermore, it also determines differential transcendency of solution of some functional equations.

Zarko Mijajlovic; Branko Malesevic

2008-04-15

4

Functional synapse formation between cultured rat accessory olfactory bulb neurons and vomeronasal pockets.  

PubMed

To investigate the interaction between vomeronasal receptor neurons and accessory olfactory bulb neurons during pheromonal signal processing and specific synapse formation, partially dissociated rat vomeronasal receptor neurons were co-cultured with accessory olfactory bulb neurons. Between 7 and 14 days in co-culture, a few bundles of fibers from a spherical structure, termed the vomeronasal pocket, of cultured vomeronasal receptor neurons extended to the accessory olfactory bulb neurons. An optical recording of the intracellular Ca(2+) concentration was used to monitor the synaptic activation of cultured accessory olfactory bulb neurons. Electrical stimulation of the vomeronasal pocket between 7 and 14 days in co-culture had no effects on most of the cultured neurons tested, although it occasionally evoked weak responses in a small number of neurons. In contrast, vomeronasal pocket stimulation after 21 days in co-culture evoked clear calcium transients in a substantial number of cultured accessory olfactory bulb neurons. These responses of accessory olfactory bulb neurons were reversibly suppressed by the application of 6-cyano-7-nitroquinoxaline-2,3-dione; the calcium transients disappeared in most of the neurons and were diminished in the others. The application of d-2-amino-5-phosphonopentanoic acid partially affected the calcium transients, but blocked spontaneous calcium increases, which were observed repeatedly in accessory olfactory bulb-alone cultures. The application of both 6-cyano-7-nitroquinoxaline-2,3-dione and d-2-amino-5-phosphonopentanoic acid completely blocked the evoked calcium transients. These results suggest that functional glutamatergic synapses between vomeronasal receptor neurons and accessory olfactory bulb neurons were formed at around 21 days in co-culture. PMID:16677769

Muramoto, K; Huang, G-Z; Taniguchi, M; Kaba, H

2006-08-11

5

Differential Item Functioning vs Differential Test Functioning.  

ERIC Educational Resources Information Center

A problem that arises when a differential item functioning (DIF) study is done with samples of examinees differing in ability is examined. A test may function differently when the populations from which the items are calibrated are not of equal ability. Since the lower ability examinees get many difficult items incorrect, the spread (standard…

Bergstrom, Betty A.; And Others

6

Partial restoration of blink reflex function after spinal accessory-facial nerve anastomosis.  

PubMed Central

Functional motor control requires perfect matching of the central connections of motoneurons with their peripheral inputs. It is not known, however, to what extent these central circuits are influenced by target muscles, either during development or after a lesion. Surgical interventions aimed at restoring function after peripheral nerve lesions provide an opportunity for studying this interaction in the mature human nervous system. A patient was studied in whom the spinal accessory nerve was anastomosed into a lesioned facial nerve, allowing voluntary contractions of the previously paralysed muscles. This procedure, in addition to replacing the facial neurons at peripheral synapses, allowed a new short latency trigeminospinal accessory reflex of the R1 blink reflex type to be demonstrated, implying that trigeminal neurons had sprouted towards spinal accessory motoneurons over a distance of at least 1 cm. These results show an unexpected influence of the periphery in remodelling central connectivity in humans. The motoneuronal excitability for this R1 reflex response was therefore studied to compare the convergent properties of facial motoneurons (normal side) with those of the spinal accessory motoneurons (operated side) using a classic double shock technique with variable interstimulus intervals (conditioning test stimulus). On the normal side, conditioning stimuli (to the ipsilateral or contralateral infraliminar supraorbital nerve) produced a clearcut facilitation of the R1 blink reflex when the interstimulus interval was 30-80 ms. By contrast, a similar procedure had no effect on the R1 blink reflex mediated via the trigeminal-spinal accessory reflex arc. These data indicate that despite the heterotopic sprouting of some axons from neurons in the XIth nucleus, motoneurons involved in the newly formed reflex arc remain totally inexcitable by other trigeminal afferents and seem unable to ensure a physiological functioning of the normal blink reflex. Thus the functional relevance of the recovered R1 blink response remains unclear. PMID:7876856

Danziger, N; Chassande, B; Lamas, G; Fligny, I; Soudant, J; Willer, J C

1995-01-01

7

The main and accessory olfactory systems of female mice are activated differentially by dominant versus subordinate male urinary odors.  

PubMed

Previous studies have shown that female preferences for male pheromones depend on the female's reproductive condition and the dominance status of the male. However, it is unknown which olfactory system detects the odors that result in a preference for a dominant male. Therefore, in the present study, we asked whether dominant versus subordinate male urinary odors differentially activate the main and accessory olfactory systems in female (C57Bl/6j) mice by monitoring the induction of the immediate early gene, c-fos. A more robust induction of Fos was observed in female mice which had direct nasal contact with dominant male urinary odors in four specific segments of the accessory olfactory system, i.e., the posteroventral part of the medial amygdala, the bed nucleus of the stria terminalis, the medial part of the preoptic nucleus and the ventrolateral part of the ventromedial hypothalamus, compared to females that were exposed to subordinate male urine. This greater activation of the accessory olfactory pathway by dominant male urine suggests that there are differences in the nonvolatile components of dominant versus subordinate male urine that are detected by the vomeronasal organ. By contrast, subordinate male urinary odors induced a greater activation in the piriform cortex which is part of the main olfactory system, suggesting that female mice discriminate between dominant and subordinate male urine using their main olfactory system as well. PMID:21683943

Veyrac, Alexandra; Wang, Guan; Baum, Michael J; Bakker, Julie

2011-07-21

8

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

PubMed

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 IFN? 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. PMID:25576824

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

2015-05-01

9

Functional organization of glomerular maps in the mouse accessory olfactory bulb  

PubMed Central

Summary The mammalian accessory olfactory system (AOS) extracts information about species, sex, and individual identity from social odors, but its functional organization remains unclear. We imaged presynaptic Ca2+ signals in vomeronasal inputs to the accessory olfactory bulb (AOB) during peripheral stimulation using light sheet microscopy. Urine- and steroid-responsive glomeruli densely innervated the anterior AOB. Glomerular activity maps for sexually mature female mouse urine overlapped maps for juvenile and/or gonadectomized urine of both sexes, whereas maps for sexually mature male urine were highly distinct. Further spatial analysis revealed a complicated organization involving selective juxtaposition and dispersal of functionally-grouped glomerular classes. Glomeruli that were similarly tuned to urines were often closely associated, whereas more disparately tuned glomeruli were selectively dispersed. Maps to a panel of sulfated steroid odorants identified tightly-juxtaposed groups that were disparately tuned and dispersed groups that were similarly tuned. These results reveal a modular, non-chemotopic spatial organization in the AOB. PMID:24880215

Hammen, Gary F.; Turaga, Diwakar; Holy, Timothy E.; Meeks, Julian P.

2014-01-01

10

Activity regulates functional connectivity from the vomeronasal organ to the accessory olfactory bulb.  

PubMed

The mammalian accessory olfactory system is specialized for the detection of chemicals that identify kin and conspecifics. Vomeronasal sensory neurons (VSNs) residing in the vomeronasal organ project axons to the accessory olfactory bulb (AOB), where they form synapses with principal neurons known as mitral cells. The organization of this projection is quite precise and is believed to be essential for appropriate function of this system. However, how this precise connectivity is established is unknown. We show here that in mice the vomeronasal duct is open at birth, allowing external chemical stimuli access to sensory neurons, and that these sensory neurons are capable of releasing neurotransmitter to downstream neurons as early as the first postnatal day (P). Using major histocompatibility complex class I peptides to activate a selective subset of VSNs during the first few postnatal days of development, we show that increased activity results in exuberant VSN axonal projections and a delay in axonal coalescence into well defined glomeruli in the AOB. Finally, we show that mitral cell dendritic refinement occurs just after the coalescence of presynaptic axons. Such a mechanism may allow the formation of precise connectivity with specific glomeruli that receive input from sensory neurons expressing the same receptor type. PMID:22674266

Hovis, Kenneth R; Ramnath, Rohit; Dahlen, Jeffrey E; Romanova, Anna L; LaRocca, Greg; Bier, Mark E; Urban, Nathaniel N

2012-06-01

11

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

PubMed

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. PMID:9403333

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

12

Matching Accessories  

NSDL National Science Digital Library

Heterodimerization enhances the complexity of ligand recognition and diversity of signaling responses of heterotrimeric guanine nucleotide-binding protein-coupled receptors (GPCRs). Many accessory proteins (for ion channels or GPCRs) appear to associate with their partners relatively early in the process whereby proteins are transported to the cell surface; their roles in modulating function may have evolved out of simple proximity to a protein that once upon a time they either facilitated or accompanied through the maturation process. The receptor activity-modifying proteins (RAMPs) are a family of single-transmembrane accessory proteins that heterodimerize with GPCRs and, thereby, allow individual GPCRs to recognize multiple ligands and to activate various signaling pathways in response to ligand binding. The M10 family of major histocompatibility complex (MHC) class 1b proteins has recently been shown to associate with murine vomeronasal V2R receptors, as well as to escort them to the cell surface. The exact role of M10 in modulating V2R function (or vice versa) remains to be determined.

Steven M. Foord (Stevenage; Target Bioinformatics, GlaxoSmithKline Medicine Research Centre REV)

2003-07-08

13

Functional morphology of the accessory neurosecretory cells of the cat hypothalamus  

Microsoft Academic Search

Accessory groups of neurosecretory cells were studied by staining serial paraffin sections of the hypothalamus by Gomori's method after stimulation of the supraoptic (SON) and postoptic (PON) nuclei, the preoptic region of the hypothalamus, the cervical sympathetic nerve (CSN) and afferent fibers of the vagus nerve in acute experiments on cats. Four paired accessory groups in the rostral hypothalamus were

E. A. Borisova

1978-01-01

14

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

PubMed

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. PMID:16775312

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

2006-07-01

15

Using Differentials to Differentiate Trigonometric and Exponential Functions  

ERIC Educational Resources Information Center

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.

Dray, Tevian

2013-01-01

16

Functional Differential Geometry  

E-print Network

Differential geometry is deceptively simple. It is surprisingly easyto get the right answer with unclear and informal symbol manipulation.To address this problem we use computer programs to communicate aprecise understanding ...

Sussman, Gerald Jay

2005-02-02

17

Investigating Differentiability of Piecewise Functions  

NSDL National Science Digital Library

Students in calculus need to be proficient in working with functions in a variety of ways: graphical, numerical, analytic, or verbal, and to understand connections among these representations. This demo provides a set of visualizations designed to help students better understand what it means for a piecewise function to be differentiable at a particular domain value.

Roberts, Lila F.

2004-10-04

18

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

PubMed Central

The vomeronasal system is crucial for social and sexual communication in mammals. Two populations of vomeronasal sensory neurons, each expressing G?i2 or G?o proteins, send projections to glomeruli of the rostral or caudal accessory olfactory bulb, rAOB and cAOB, respectively. In rodents, the G?i2- and G?o-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

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

2011-01-01

19

Effect of an indigenous drug (Speman) on accessory reproductive functions of mice.  

PubMed

The effects of an indigenous drug preparation, Speman (Himalaya Drug Company), on the accessory reproductive organs were studied in castrated adult mice and immature intact mice. Oral administration of Speman to castrated adults markedly increased the weights of the seminal vesicles and ventral prostate, as well as the level of fructose and maltase activity. These increases were dose-dependent and highly significant (p less than .001). The results indicate that Speman possesses both androgenic and anaboliclike activities. PMID:992734

Jayatilak, P G; Pardanani, D S; Dattatreya, B; Sheth, A R

1976-03-01

20

Effects of unpolymerized resin components on the function of accessory cells derived from the rat incisor pulp.  

PubMed

Monomeric resin components from dental composites are toxic to fibroblasts in culture and thus may interfere with the local immune system of the pulp, reducing its effective defense potential, either by cytotoxicity or by a more specific immune mechanism. Therefore, the present study was undertaken to observe the cytotoxic effects elicited by certain unpolymerized components of resin composites upon the function of accessory pulp cells in mitogen-induced proliferation of T-lymphocytes. Accessory cells from the rat incisor pulp were released following enzymatic digestion with collagenase. The assay included incubation of these cells with purified T-lymphocytes from cervical lymph nodes for 72 h in the presence of different concentrations of the resin components. The proliferative T-lymphocyte response was monitored by 3H-thymidine incorporation. Initially, we conducted experiments on spleen cells to determine the proper concentration intervals for suitable testing of the resin components. To assess the individual susceptibility of accessory cells and T-lymphocytes, we pre-treated each of these cells with some of the test materials prior to assay. At low concentrations, urethane dimethacrylate (UDMA), bisglycidyl methacrylate (bis-GMA), triethylene glycol dimethacrylate (TEGDMA), and bis-phenol A (BPA) increased spleen cell proliferation to concanavalin A (con A). Purified T-lymphocytes stimulated by pulpal cells did not show enhanced responses to UDMA, bis-GMA, glycidyl mehtacrylate (GMA), or N,N,-dihydroxyethyl-p-toluidine (DHEpT). At higher concentrations, all substances except camphoroquinone (CAMP) showed inhibitory effects in both test systems. The in vitro study shows that resin components can evoke either immunosuppression or immunostimulation on mitogen-driven proliferation of purified T-lyumphocytes and spleen cells. PMID:7790593

Jontell, M; Hanks, C T; Bratel, J; Bergenholtz, G

1995-05-01

21

Functional Differential Equations in Sustainable Forest Harvesting  

E-print Network

Functional Differential Equations in Sustainable Forest Harvesting Oscar Garc´ia Unit of Forestry of partial differential equations, delay differential equations, and non-linear integral equations. Equilib in the rela- tion between integral equations and delay differential equations derived from them. The basic

García, Oscar

22

Functions of replication factor C and proliferating-cell nuclear antigen: Functional similarity of DNA polymerase accessory proteins from human cells and bacteriophage T4  

SciTech Connect

The proliferating-cell nuclear antigen (PCNA) and the replication factors A and C (RF-A and RF-C) are cellular proteins essential for complete elongation of DNA during synthesis from the simian virus 40 origin of DNA replication in vitro. All three cooperate to stimulate processive DNA synthesis by DNA polymerase {delta} on a primed single-stranded M13 template DNA and as such can be categorized as DNA polymerase accessory proteins. Biochemical analyses with highly purified RF-C and PCNA have demonstrated functions that are completely analogous to the functions of bacteriophage T4 DNA polymerase accessory proteins. A primer-template-specific DNA binding activity and a DNA-dependent ATPase activity copurified with the multisubunit protein RF-C and are similar to the functions of the phage T4 gene 44/62 protein complex. Furthermore, PCNA stimulated the RF-C ATPase activity and is, therefore, analogous to the phage T4 gene 45 protein, which stimulates the ATPase function of the gene 44/62 protein complex. Indeed, some primary sequence similarities between human PCNA and the phage T4 gene 45 protein could be detected. These results demonstrate a striking conservation of the DNA replication apparatus in human cells and bacteriophage T4.

Tsurimoto, Toshiki; Stillman, B. (Cold Spring Harbor Laboratory, NY (USA))

1990-02-01

23

Dissipativity of Volterra functional differential equations  

NASA Astrophysics Data System (ADS)

This paper is concerned with the dissipativity of Volterra functional differential equations in a Hilbert space. A sufficient condition for dissipativity of one class of such equations is obtained. This result is applied to delay differential equations and integro-differential equations to obtain dissipativity results that are more general and deeper than related results in the previous literature.

Wen, Liping; Li, Shoufu

2006-12-01

24

Function and composition of male accessory gland secretions in Anopheles gambiae: a comparison with other insect vectors of infectious diseases  

PubMed Central

Human malaria, a major public health burden in tropical and subtropical countries, is transmitted exclusively by the bite of a female Anopheles mosquito. Malaria control strategies aimed at inducing sexual sterility in natural vector populations are an attractive alternative to the use of insecticides. However, despite their importance as disease vectors, limited information is available on the molecular mechanisms regulating fertility in Anopheles mosquitoes. In the major malaria vector, An. gambiae, the full complement of sperm and seminal fluid required for a female’s lifelong egg production is obtained from a single mating event. This single mating has important consequences for the physiology and behavior of An. gambiae females: in particular, they become refractory to further insemination, and they start laying eggs. In other insects including Drosophila, similar post-copulatory changes are induced by seminal proteins secreted by the male accessory glands and transferred to the female during mating. In this review, we analyze the current state of knowledge on the function and characterization of male seminal proteins in An. gambiae, and provide a comparative assessment of the role of these male reproductive factors in other mosquito vectors of human disease in which female post-copulatory behavior has been studied. Knowledge of the factors and mechanisms regulating fertility in An. gambiae and other vectors can help the design of novel control strategies to fight the spread of disease. PMID:22943543

Baldini, Francesco; Gabrieli, Paolo; Rogers, David W.; Catteruccia, Flaminia

2012-01-01

25

A novel ML protein from Manduca sexta may function as a key accessory protein for lipopolysaccharide signaling  

PubMed Central

Lipopolysaccharide (LPS) present on the outer membrane of Gram-negative bacteria is one of the most important pathogen-associated molecular patterns and a potent elicitor in innate immunity. In human, TLR4 (Toll-like receptor 4) and MD-2 (myeloid differiation-2) form a receptor complex to transduce the LPS signal into cells. However, in invertebrates, receptors that recognize LPS have not been determined. Here we report the purification, characterization and cDNA cloning of an ML (MD-2-related lipid-recognition) protein from the tobacco hornworm Manduca sexta. The full-length cDNA of this M. sexta ML protein, named MsML-1, is 532 bp with an open reading frame of 456 bp that encodes a polypeptide of 151 amino acids containing an ML domain. MsML-1 is a secreted glycoprotein and its mRNA is expressed in fat body and hemocytes. The expression level of MsML-1 mRNA in fat body and hemocytes as well as MsML-1 protein in hemolymph are not induced by immune challenge. Recombinant MsML-1 protein specifically binds to LPS from several Gram-negative bacteria and LPS Re mutant, as well as to lipid A, but not to KDO (2-keto-3-deoxyoctonate). Our results suggest that MsML-1 may function as a key accessory protein for LPS signaling in M. sexta against Gram-negative bacterial infection. PMID:18343500

Ao, Jing-qun; Ling, Erjun; Rao, Xiang-jun; Yu, Xiao-Qiang

2015-01-01

26

Identifying Possible Sources of Differential Functioning Using Differential Bundle Functioning with Polytomously Scored Data  

ERIC Educational Resources Information Center

Oshima, Raju, Flowers, and Slinde (1998) described procedures for identifying sources of differential functioning for dichotomous data using differential bundle functioning (DBF) derived from the differential functioning of items and test (DFIT) framework (Raju, van der Linden, & Fleer, 1995). The purpose of this study was to extend the procedures…

McCarty, F. A.; Oshima, T. C.; Raju, Nambury S.

2007-01-01

27

Extracting differential pair distribution functions using MIXSCAT  

SciTech Connect

Differently weighted experimental scattering data have been used to extract partial or differential structure factors or pair distribution functions in studying many materials. However, this is not done routinely partly because of the lack of user-friendly software. This paper presents MIXSCAT, a new member of the DISCUS program package. MIXSCAT allows one to combine neutron and X-ray pair distribution functions and extract their respective differential functions.

Wurden, Caroline; Page, Katharine; Llobet, Anna; White, Claire E.; Proffen, Thomas (LANL)

2010-08-27

28

On differentiability of volume time functions  

E-print Network

We show differentiability of a class of Geroch's volume functions on globally hyperbolic manifolds. Furthermore, we prove that every volume function satisfies a local anti-Lipschitz condition over causal curves, and that locally Lipschitz time functions which are locally anti-Lipschitz can be uniformly approximated by smooth time functions with timelike gradient. Finally, we prove that in stably causal spacetimes Hawking's time function can be uniformly approximated by smooth time functions with timelike gradient.

Piotr T. Chru?ciel; James D. E. Grant; Ettore Minguzzi

2013-01-14

29

Transient and sustained afterdepolarizations in accessory olfactory bulb mitral cells are mediated by distinct mechanisms that are differentially regulated by neuromodulators.  

PubMed

Social interactions between mammalian conspecifics rely heavily on molecular communication via the main and accessory olfactory systems. These two chemosensory systems show high similarity in the organization of information flow along their early stages: social chemical cues are detected by the sensory neurons of the main olfactory epithelium and the vomeronasal organ. These neurons then convey sensory information to the main (MOB) and accessory (AOB) olfactory bulbs, respectively, where they synapse upon mitral cells that project to higher brain areas. Yet, the functional difference between these two chemosensory systems remains unclear. We have previously shown that MOB and AOB mitral cells exhibit very distinct intrinsic biophysical properties leading to different types of information processing. Specifically, we found that unlike MOB mitral cells, AOB neurons display persistent firing responses to strong stimuli. These prolonged responses are mediated by long-lasting calcium-activated non-selective cationic current (Ican). In the current study we further examined the firing characteristics of these cells and their modulation by several neuromodulators. We found that AOB mitral cells display transient depolarizing afterpotentials (DAPs) following moderate firing. These DAPs are not found in MOB mitral cells that show instead robust hyperpolarizing afterpotentials. Unlike Ican, the DAPs of AOB mitral cells are activated by low levels of intracellular calcium and are relatively insensitive to flufenamic acid. Moreover, the cholinergic agonist carbachol exerts opposite effects on the persistent firing and DAPs of AOB mitral cells. We conclude that these phenomena are mediated by distinct biophysical mechanisms that may serve to mediate different types of information processing in the AOB at distinct brain states. PMID:25642164

Shpak, Guy; Zylbertal, Asaph; Wagner, Shlomo

2014-01-01

30

Hemolymph circulation in insect sensory appendages: functional mechanics of antennal accessory pulsatile organs (auxiliary hearts) in the mosquito Anopheles gambiae.  

PubMed

Mosquito antennae provide sensory input that modulates host-seeking, mating and oviposition behaviors. Thus, mosquitoes must ensure the efficient transport of molecules into and out of these appendages. To accomplish this, mosquitoes and other insects have evolved antennal accessory pulsatile organs (APOs) that drive hemolymph into the antennal space. This study characterizes the structural mechanics of hemolymph propulsion throughout the antennae of Anopheles gambiae. Using intravital video imaging, we show that mosquitoes possess paired antennal APOs that are located on each side of the head's dorsal midline. They are situated between the frons and the vertex in an area that is dorsal to the antenna but ventral to the medial-most region of the compound eyes. Antennal APOs contract in synchrony at 1 Hz, which is 45% slower than the heart. By means of histology and intravital imaging, we show that each antennal APO propels hemolymph into the antenna through an antennal vessel that traverses the length of the appendage and has an effective diameter of 1-2 ?m. When hemolymph reaches the end of the appendage, it is discharged into the antennal hemocoel and returns to the head. Because a narrow vessel empties into a larger cavity, hemolymph travels up the antenna at 0.2 mm s(-1) but reduces its velocity by 75% as it returns to the head. Finally, treatment of mosquitoes with the anesthetic agent FlyNap (triethylamine) increases both antennal APO and heart contraction rates. In summary, this study presents a comprehensive functional characterization of circulatory physiology in the mosquito antennae. PMID:24948635

Boppana, Sushma; Hillyer, Julián F

2014-09-01

31

Functional analysis of the accessory protein TapA in Bacillus subtilis amyloid fiber assembly.  

PubMed

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

Romero, Diego; Vlamakis, Hera; Losick, Richard; Kolter, Roberto

2014-04-01

32

Large granular lymphocytes provide an accessory function in the in vitro development of influenza A virus-specific cytotoxic T cells.  

PubMed

We report that large granular lymphocytes (LGL) have an accessory function in the development of cytotoxic T cells (Tc) through the production of soluble factor(s). LGL and T cells were separated on Percoll gradients and the ability of the separated and of the recombined LGL and T cells to generate influenza A virus-specific Tc activity was measured. When stimulated by virus-infected, irradiated, adherent cells, neither LGL nor T cells cultured separately produced Tc activity. When they were co-cultured, however, even if separated by a 0.22-micron pore size membrane, Tc responses were readily generated from the small T cell precursors and natural killer activity was maintained in the LGL. Thus, LGL were required as accessory cells for Tc responses to occur and the effect was mediated by a soluble factor(s). alpha-Interferon (IFN) was produced in cultures containing LGL and/or stimulating adherent cells, whereas gamma-IFN was only produced in cultures containing both LGL and T cells. Therefore, neither alpha- nor gamma-IFN appeared to be the LGL produced soluble factor that mediated the accessory effect of LGL on Tc responses. PMID:6202775

Burlington, D B; Djeu, J Y; Wells, M A; Kiley, S C; Quinnan, G V

1984-06-01

33

Effect of sonicated material from Fusobacterium nucleatum on the functional capacity of accessory cells derived from dental pulp.  

PubMed

Fusobacterium nucleatum-derived components were studied for their effect on the ability of accessory pulpal cells to induce T-lymphocyte proliferation. In initial experiments, spleen cells were used to establish concentration ranges at which testing of the effect of the bacterial components would be suitable. At low concentrations, bacterial substances induced a stimulatory effect on the proliferation rate of spleen cells, but not when purified T-lymphocytes were incubated in the presence of concanavalin A and pulpal accessory cells. At increasing concentrations, a dose-dependent reduction was observed. Pretreatment with the bacterial products for 4 h gave a stimulatory effect in the absence of concanavalin A for both spleen cells and T-lymphocytes. Removal of low-molecular weight components (<3.5 kDa) did not influence the inhibitory effect, whereas preheating the bacterial substances to 100 degrees C eliminated the observed inhibition. Findings show that heat-sensitive, high-molecular-weight components of F. nucleatum can evoke a concentration-dependent stimulatory or suppressive effect on the proliferation rate of T-lymphocytes in the presence of accessory cells derived from the dental pulp. PMID:8602332

Yoshida, H; Jontell, M; Sundqvist, G; Bergenholtz, G

1995-08-01

34

Differentiation status dependent function of FOG1  

Microsoft Academic Search

The molecular interactions between transcription factors and cofactors play crucial roles in various biological processes, including haematopoiesis. FOG-1 is a cognate cofactor of GATA-1, and the FOG-1\\/GATA-1 complex is essential for the haematopoietic differentiation of erythroid cells and megakaryocytes. In order to elucidate the biological functions of FOG-1 in the different contexts of cell differentiation, we analysed the effects of

Makoto Tanaka; Jie Zheng; Kenji Kitajima; Keisuke Kit; Hideki Yoshikawa; Toru Nakano

35

Examining the Relationship between Differential Item Functioning and Differential Test Functioning  

ERIC Educational Resources Information Center

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,…

Pae, Tae-Il; Park, Gi-Pyo

2006-01-01

36

CD4+T Cells: Differentiation and Functions  

PubMed Central

CD4+T cells are crucial in achieving a regulated effective immune response to pathogens. Naive CD4+T cells are activated after interaction with antigen-MHC complex and differentiate into specific subtypes depending mainly on the cytokine milieu of the microenvironment. Besides the classical T-helper 1 and T-helper 2, other subsets have been identified, including T-helper 17, regulatory T cell, follicular helper T cell, and T-helper 9, each with a characteristic cytokine profile. For a particular phenotype to be differentiated, a set of cytokine signaling pathways coupled with activation of lineage-specific transcription factors and epigenetic modifications at appropriate genes are required. The effector functions of these cells are mediated by the cytokines secreted by the differentiated cells. This paper will focus on the cytokine-signaling and the network of transcription factors responsible for the differentiation of naive CD4+T cells. PMID:22474485

Luckheeram, Rishi Vishal; Zhou, Rui; Verma, Asha Devi; Xia, Bing

2012-01-01

37

Solving Differential Equations with Radial Basis Functions  

E-print Network

Gregory E. Fasshauer Abstract. Some of the meshless radial basis function methods used for the numerical­called meshless methods for the numerical solution of partial differential equations (PDEs) has received much at in a more general setting. One of the common ideas behind all meshless methods is the wish to design

Fasshauer, Greg

38

A Multilevel Assessment of Differential Item Functioning.  

ERIC Educational Resources Information Center

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…

Shen, Linjun

39

Differential Item Functioning Analysis Using Rasch Item Information Functions  

ERIC Educational Resources Information Center

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…

Wyse, Adam E.; Mapuranga, Raymond

2009-01-01

40

An Expected Response Function Approach to Graphical Differential Item Functioning.  

ERIC Educational Resources Information Center

Presents an approach to graphical differential item functioning (DIF) based on a sampling-theory approach to expected response functions. Applied the approach to a set of pretest items and compared results to traditional Mantel Haenszel DIF statistics. Discusses implications of the method as a complement to the approach of P. Pashley (1992). (SLD)

Scrams, David J.; McLeod, Lori D.

2000-01-01

41

Differential pleiotropy and HOX functional organization.  

PubMed

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. PMID:25448696

Sivanantharajah, Lovesha; Percival-Smith, Anthony

2015-02-01

42

Structural and functional association between substance P- and calcitonin gene-related peptide-immunoreactive nerves and accessory cells in the rat dental pulp.  

PubMed

Defense mechanisms of the dentin/pulp complex involve a variety of biological systems in which immunocompetent cells, the nervous system, and the vascular supply play important roles. In the present study, pulpal accessory cells were examined regarding (i) their structural relationship to nerves and (ii) how the functional capacities of these cells were affected by neuropeptides. Micro-anatomic association was investigated in the normal rat molar pulp with the use of double-immunofluorescence staining and dual-channel confocal laser scanning microscopy. Examinations of confocal laser scanning microscopic images from single focal planes revealed the presence of apparent contacts between thin, varicose nerve fibers and immunocompetent cells, indicating proximity between these two structures. The close associations were most frequently observed in the para-odontoblastic region of the coronal pulp, where more than 70% of class II antigen-expressing (OX6+) cells showed proximity to nerve fibers immunoreactive to calcitonin gene-related peptide. The corresponding figure for substance P was about 50%. ED2+ macrophages closely associated with nerves were less frequently observed. Functional studies conducted in vitro demonstrated that 10(-9) to 10(-7) mol/L of substance P significantly increased (p < 0.05), while 10(-7) to 10(-6) mol/L of calcitonin gene-related peptide suppressed (p < 0.01) proliferation of purified T-lymphocytes stimulated with sub-optimal concentrations of concanavalin A in the presence of rat incisor pulpal cells as accessory cells. These data suggest that pulpal sensory nerve fibers and their products may have an influence upon the immune defense of the dental pulp. PMID:9390474

Okiji, T; Jontell, M; Belichenko, P; Dahlgren, U; Bergenholtz, G; Dahlström, A

1997-12-01

43

Visual determination of differential renal function  

SciTech Connect

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.

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

1986-05-01

44

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

PubMed Central

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. PMID:17502602

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

2007-01-01

45

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

ERIC Educational Resources Information Center

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…

Beretvas, S. Natasha; Walker, Cindy M.

2012-01-01

46

Using differentials to differentiate trigonometric and exponential functions  

E-print Network

, and we also have the (infinitesimal) Pythagorean theorem, ds2 = dx2 + dy2 . Furthermore, from x2 + y2 = r more than their geometric definition, the Pythagorean theorem, and the ability to differentiate simple

47

Legendre-tau approximations for functional differential equations  

NASA Technical Reports Server (NTRS)

The numerical approximation of solutions to linear retarded 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 approximation is made.

Ito, K.; Teglas, R.

1986-01-01

48

Generalized Halanay inequalities for dissipativity of Volterra functional differential equations  

NASA Astrophysics Data System (ADS)

This paper is concerned with the dissipativity of theoretical solutions to nonlinear Volterra functional differential equations (VFDEs). At first, we give some generalizations of Halanay's inequality which play an important role in study of dissipativity and stability of differential equations. Then, by applying the generalization of Halanay's inequality, the dissipativity results of VFDEs are obtained, which provides unified theoretical foundation for the dissipativity analysis of systems in ordinary differential equations (ODEs), delay differential equations (DDEs), integro-differential equations (IDEs), Volterra delay-integro-differential equations (VDIDEs) and VFDEs of other type which appear in practice.

Wen, Liping; Yu, Yuexin; Wang, Wansheng

2008-11-01

49

Computations involving differential operators and their actions on functions  

NASA Technical Reports Server (NTRS)

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.

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

1991-01-01

50

DIF Trees: Using Classification Trees to Detect Differential Item Functioning  

ERIC Educational Resources Information Center

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…

Vaughn, Brandon K.; Wang, Qiu

2010-01-01

51

Modular differential equations for torus one-point functions  

E-print Network

It is shown that in a rational conformal field theory every torus one-point function of a given highest weight state satisfies a modular differential equation. We derive and solve these differential equations explicitly for some Virasoro minimal models. In general, however, the resulting amplitudes do not seem to be expressible in terms of standard transcendental functions.

Matthias R Gaberdiel; Samuel Lang

2008-11-17

52

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

ERIC Educational Resources Information Center

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…

Akour, Mutasem; Sabah, Saed; Hammouri, Hind

2015-01-01

53

Dendritic cells are specialized accessory cells along with TGF-? for the differentiation of Foxp3+ CD4+ regulatory T cells from peripheral Foxp3- precursors  

Microsoft Academic Search

Foxp3CD25CD4 regulatory T cells are produced in the thymus (natural T regs) but can also differentiate from peripheral Foxp3CD4 precursors (induced or adaptive T regs). We assessed antigen presenting cell (APC) requirements for the latter differentiation. With added trans- forminggrowthfactor(TGF)-,bothimma- ture and mature populations of dendritic cells (DCs) induced antigen-specific Foxp3 T regs from Foxp3 precursors. Using endogenous TGF-, DCs

Sayuri Yamazaki; Anthony J. Bonito; Radek Spisek; Madhav Dhodapkar; Kayo Inaba; Ralph M. Steinman

2007-01-01

54

Application of Lie group analysis to functional differential equations  

E-print Network

In the present paper the classical point symmetry analysis is extended from partial differential to functional differential equations with functional derivatives. In order to perform the group analysis and deal with the functional derivatives we extend the quantities such as infinitesimal transformations, prolongations and invariant solutions. For the sake of example the procedure is applied to the continuum limit of the heat equation. The method can further lead to significant applications in statistical physics and fluid dynamics.

Martin Oberlack; Marta Waclawczyk

2006-10-27

55

Function expansion methods for solving autonomous nonlinear partial differential equations  

E-print Network

In this paper, we propose some algorithms for analytical solution construction to nonlinear polynomial partial differential equations with constant function coefficients. These schemes are based on one-(single), two- (double) or three- (triple) function expansion methods. Most of the existing expansion function methods are well recovered from the mentioned schemes. The effectiveness of these methods has been tested on some nonlinear partial differential equations (NLPDEs) describing important phenomena in physics.

Mahouton Norbert Hounkonnou; Pascal Alain Dkengne Sielenou

2011-10-02

56

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

PubMed Central

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 of each ovipositor valve operates like a bellow. It forces hemolymph via sinuses delimited by thin septa of connective tissue in a countercurrent flow through the valve lumen. The pumping activity is based on neurogenic control by a central pattern generator in the terminal ganglion. PMID:25018774

2014-01-01

57

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

ERIC Educational Resources Information Center

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…

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

2009-01-01

58

Curriculum, Translation, and Differential Functioning of Measurement and Geometry Items  

ERIC Educational Resources Information Center

A test item exhibits differential item functioning (DIF) if students with the same ability find it differentially difficult. When the item is administered in French and English, differences in language difficulty and meaning are the most likely explanations. However, curriculum differences may also contribute to DIF. The responses of Ontario…

Emenogu, Barnabas C.; Childs, Ruth A.

2005-01-01

59

Thermomechanical milling of accessory lithics in volcanic conduits  

NASA Astrophysics Data System (ADS)

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 (?) 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 smaller clasts due to longer residence times and to greater differential velocities within the ash-laden jet. Lastly, our model residence times and mass loss estimates for rounded clasts are used to estimate minimum attrition rates due to volcanic ash-blasting within the conduit (e.g., 12 cm3?s-1 for 25 cm clasts, sourced at 2500 m depth).

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

2013-09-01

60

Fuzzy fractional functional differential equations under Caputo gH-differentiability  

NASA Astrophysics Data System (ADS)

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.

Hoa, Ngo Van

2015-05-01

61

Functional differentiability in time-dependent quantum mechanics.  

PubMed

In this work, we investigate the functional differentiability of the time-dependent many-body wave function and of derived quantities with respect to time-dependent potentials. For properly chosen Banach spaces of potentials and wave functions, Fréchet differentiability is proven. From this follows an estimate for the difference of two solutions to the time-dependent Schrödinger equation that evolve under the influence of different potentials. Such results can be applied directly to the one-particle density and to bounded operators, and present a rigorous formulation of non-equilibrium linear-response theory where the usual Lehmann representation of the linear-response kernel is not valid. Further, the Fréchet differentiability of the wave function provides a new route towards proving basic properties of time-dependent density-functional theory. PMID:25833571

Penz, Markus; Ruggenthaler, Michael

2015-03-28

62

Generating functionals and Lagrangian partial differential equations  

NASA Astrophysics Data System (ADS)

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.

Vankerschaver, Joris; Liao, Cuicui; Leok, Melvin

2013-08-01

63

Generating functionals and Lagrangian partial differential equations  

SciTech Connect

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.

Vankerschaver, Joris; Liao, Cuicui; Leok, Melvin [Department of Mathematics, University of California, San Diego, 9500 Gilman Drive, Dept. 0112, La Jolla, California 92093-0112 (United States)] [Department of Mathematics, University of California, San Diego, 9500 Gilman Drive, Dept. 0112, La Jolla, California 92093-0112 (United States)

2013-08-15

64

Introduction to Differential Equations A differential equation is an equation for an unknown function that involves the derivative  

E-print Network

Introduction to Differential Equations A differential equation is an equation for an unknown is a differential equation for an unknown function, y(x). This particular equation is said to be a first order linear differential equation. · It is a differential equation because it involves the derivative dy dx

Feldman, Joel

65

Solving Differential Equations with Radial Basis Functions  

E-print Network

. Fasshauer Abstract. Some of the meshless radial basis function methods used for the numerical the past few years the idea of using so-called meshless methods for the numerical solution of partial general setting. One of the common ideas behind all meshless methods is the wish to design

Fasshauer, Greg

66

Differential mobility analyser transfer functions in scanning mode  

Microsoft Academic Search

A novel method is described for the calculation of the differential mobility analyser (DMA) transfer function in scanning mode, which is based on the derivation of an analytical solution for the non-diffusive particle trajectories inside the DMA, under exponentially varying electrical field and fully developed laminar flow. The scanning mode transfer functions can substantially improve the measurement accuracy of fast

Athanasios Mamakos; Leonidas Ntziachristos; Zissis Samaras

2008-01-01

67

Raju's Differential Functioning of Items and Tests (DFIT)  

ERIC Educational Resources Information Center

Nambury S. Raju (1937-2005) developed two model-based indices for differential item functioning (DIF) during his prolific career in psychometrics. Both methods, Raju's area measures (Raju, 1988) and Raju's DFIT (Raju, van der Linden, & Fleer, 1995), are based on quantifying the gap between item characteristic functions (ICFs). This approach…

Oshima, T. C.; Morris, S. B.

2008-01-01

68

Decisions that Make a Difference in Detecting Differential Item Functioning  

ERIC Educational Resources Information Center

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…

Sireci, Stephen G.; Rios, Joseph A.

2013-01-01

69

The fully-differential quark beam function at NNLO  

NASA Astrophysics Data System (ADS)

We present the first calculation of a fully-unintegrated parton distribution (beam function) at next-to-next-to-leading order (NNLO). We obtain the fully-differential beam function for quark-initiated processes by matching it onto standard parton distribution functions (PDFs) at two loops. The fully-differential beam function is a universal ingredient in resummed predictions of observables probing both the virtuality as well as the transverse momentum of the incoming quark in addition to its usual longitudinal momentum fraction. For such double-differential observables our result provides the part of the NNLO singular cross section related to collinear initial-state radiation (ISR), and is important for the resummation of large logarithms through N3LL.

Gaunt, Jonathan R.; Stahlhofen, Maximilian

2014-12-01

70

Subunits of flagellar accessory tubules.  

PubMed

Many sperm flagella contain a central pair of singlet tubules surrounded by nine doublet tubules. Insect sperm flagella, however, usually contain in addition to the typical 9+2 arrangement of tubules, an additional row of nine singlet tubules which are called accessory tubules. Each of these accessory tubules in the Colorado potato beetle (Leptinotarsa decemlineata (Say)) contains a single central prototubule surrounded by an array of 15 or 16 peripheral prototubules. The number of prototubules in the accessory tubules of Leptinotarsa decemlineata was determined with an electron microscope and image details were reinforced by the rotation techniques of Markham. PMID:18631486

Shay, J W; Dobson, W J; Simmons, E E; Biesele, J J; Breland, O P

1969-01-01

71

Evaluation of a differentiation model of preschoolers’ executive functions  

PubMed Central

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. PMID:25852603

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

2015-01-01

72

Evaluation of a differentiation model of preschoolers' executive functions.  

PubMed

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. PMID:25852603

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

2015-01-01

73

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

PubMed Central

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

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

2013-01-01

74

A functional and phenotypic study on immune accessory cells isolated from the thyroids of Wistar and autoimmune-prone BB-DP rats.  

PubMed

Dendritic cells (DCs) comprise a small population of cells in the normal thyroid. These excellent antigen-presenting cells (APCs) are thought to be involved in the initiation of thyroid autoimmune reactions. However it is not known whether the APCs involved in this process are indeed DCs, or thyrocytes. Our aims were as follows: (1) to isolate DCs from the thyroid of normal Wistar rats and BB-DP rats prior to the development of lymphocytic thyroiditis; (2) to determine the T-cell stimulatory capability of such isolated thyroid DCs and to compare this capability to that of BB-DP thyrocytes and splenic DCs; and (3) to investigate the phenotype of isolated thyroid DCs and to compare it to that of splenic DCs; and (4) to investigate the capability of such thyroid DCs to regulate thyrocyte growth and function, and to compare it to our earlier reports demonstrating such capability with splenic DCs. Leukokcytic cell fractions were isolated from the thyroids of BB-DP and control Wistar rats of 7-20 weeks of age. The isolation steps included gentle enzymatic tissue disruption, the collection of non-plastic adherent cells and density gradient centrifugation of these cells to yield a low and a high density non-adherent fraction. The low density cell (LDC) fraction was composed of 50-75% leukocytes in both strains. These leukocytes were almost exclusively ED1+ monocytes or MHC-class II+ DC. The high density cell (HDC) fractions of both strains were composed of about 70% MHC-class II-negative thyrocytes and 30% ED1+ monocytes. The thyroid LDCs of both strains had an APC capability in syngeneic(syn)-MLR comparable to that of splenic DCs. However, the HDCs were extremely poor in syngeneic T cell stimulation. There was a difference in composition between the Wistar and the BB-DP LDC fractions: The Wistar LDCs were composed of 30-35% ED1+ monocytes and 15-20% typical MHC-II+ DCs, while BB-DP LDC fractions contained more ED1+ monocytes (about 70%), but fewer DCs (5-10%). In comparison to splenic DCs, thyroid DCs had a low CD80 and CD86 expression in both strains (i.e., an 'immature' phenotype). The LDCs of both animal strains were shown to decrease both basal and TSH-stimulated thyrocyte proliferation and T(3)release by about half. This report shows that a cell fraction enriched for monocytes and DCs can be isolated from the thyroids of both Wistar and BB-DP rats. The cells in this fraction were as capable as splenic DCs to act as T cell stimulators in syn-MLR. Since the thyroid HDCs (predominantly thyrocytes) were very poor at such T cell stimulation, thyroid monocytes and DCs (and not thyrocytes) are the prime candidates to act as immune accessory cells in the initiation of thyroid autoimmunity in the rat. Wistar thyroid LDCs differed in phenotype from BB-DP LDCs. The latter contained a lower percentage of DCs and a higher percentage of their precursors, the monocytes. Interestingly, a defect in the transition of monocytes to DCs has been described in another animal model of autoimmune thyroiditis/insulitis (the NOD mouse), as well as in thyroiditis and diabetic patients. PMID:11090240

Simons, P J; Delemarre, F G; Drexhage, H A

2000-12-01

75

An Accessory Peroneocalcaneus Internus Muscle with MRI and US Correlation  

PubMed Central

The peroneocalcaneus internus (PCI) is a rare accessory muscle of the medial ankle with typical MRI anatomic features allowing differentiation from the more common accessory flexor digitorum longus muscle. To our knowledge, there have been no previously published sonographic images of the peroneocalcaneus internus. A PCI is typically an incidental, asymptomatic finding, but knowledge of the entity may avoid confusion when initially encountered by diagnostic ultrasound. We review the anatomic imaging features which allow for a confident imaging diagnosis and the clinical relevance of this anomaly. PMID:23378873

Howe, Benjamin Matthew; Murthy, Naveen Srinivasa

2012-01-01

76

The beta function of N = 1 SYM in differential renormalization  

NASA Astrophysics Data System (ADS)

Using differential renormalization, we calculate the complete two-point function of the background gauge superfield in pure N = 1 supersymmetric Yang-Mills theory to two loops. Ultraviolet and (off-shell) infrared divergences are renormalized in position and momentum space respectively. This allows us to reobtain the beta function from the dependence on the ultraviolet renormalization scale in an infrared-safe way. The two-loop coefficient of the beta function is generated by the one-loop ultraviolet renormalization of the quantum gauge field via nonlocal terms which are infrared divergent on shell. We also discuss the connection of the beta function to the flow of the wilsonian coupling.

Mas, Javier; Seijas, Cesar; Pérez-Victoria, Manuel

2002-03-01

77

DIFAS: Differential Item Functioning Analysis System. Computer Program Exchange  

ERIC Educational Resources Information Center

Differential item functioning (DIF) is an important consideration in assessing the validity of test scores (Camilli & Shepard, 1994). A variety of statistical procedures have been developed to assess DIF in tests of dichotomous (Hills, 1989; Millsap & Everson, 1993) and polytomous (Penfield & Lam, 2000; Potenza & Dorans, 1995) items. Some of these…

Penfield, Randall D.

2005-01-01

78

Explanatory Secondary Dimension Modeling of Latent Differential Item Functioning  

ERIC Educational Resources Information Center

The models used in this article are secondary dimension mixture models with the potential to explain differential item functioning (DIF) between latent classes, called latent DIF. The focus is on models with a secondary dimension that is at the same time specific to the DIF latent class and linked to an item property. A description of the models…

De Boeck, Paul; Cho, Sun-Joo; Wilson, Mark

2011-01-01

79

Modeling Effects of Differential Item Functioning in Polytomous Items.  

ERIC Educational Resources Information Center

Extended conventional two-group differential item function (DIF) analysis for dichotomous items to factorial DIF analysis for polytomous items where multiple grouping factors with multiple groups in each are analyzed jointly. Simulation studies and analysis of a real data set with 1,924 subjects show the parameters of the proposed modeling can be…

Wang, Wen-Chung

2000-01-01

80

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...

81

Effect of Multiple Testing Adjustment in Differential Item Functioning Detection  

ERIC Educational Resources Information Center

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…

Kim, Jihye; Oshima, T. C.

2013-01-01

82

Bounded and periodic solutions of nonlinear functional differential equations  

SciTech Connect

Conditions for the existence of bounded and periodic solutions of the nonlinear functional differential equation d{sup m}x(t)/dt{sup m} + (Fx)(t) = h(t), t element of R, are presented, involving local linear approximations to the operator F. Bibliography: 23 titles.

Slyusarchuk, Vasilii E [Ukranian State Academy of Water Economy (Ukraine)

2012-05-31

83

Differentiation  

NSDL National Science Digital Library

In the five parts of this video, we define the derivative and then build a cribsheet of rules for expressing the slopes of simple functions and combinations of functions. These include the power rule, the chain rule, the product and quotient rules, and the rules for differentiating sinusoidal functions.

2013-06-21

84

Differentiation  

NSDL National Science Digital Library

The derivative refers to the rate of change, or slope, of a function. Differentiation refers to the calculation of a derivative. Derivatives are used throughout applied mathematics and science. The derivative of a function is the instantaneous rate of change of a function evaluated at each point.

David Joiner

85

Altered functional differentiation of mesoangioblasts in a genetic myopathy  

PubMed Central

Mutations underlying genetic cardiomyopathies might affect differentiation commitment of resident progenitor cells. Cardiac mesoangioblasts (cMabs) are multipotent progenitor cells resident in the myocardium. A switch from cardiac to skeletal muscle differentiation has been recently described in cMabs from ?-sarcoglycan-null mice (?SG?/?), a murine model of genetic myopathy with early myocardial involvement. Although complementation with ?SG gene was inconsequential, knock-in of miRNA669a (missing in ?SG?/? cMabs) partially rescued the mutation-induced molecular phenotype. Here, we undertook a detailed evaluation of functional differentiation of ?SG?/? cMabs and tested the effects of miRNA669a-induced rescue in vitro. To this end, cMabs were compared with neonatal cardiomyocytes (CMs) and skeletal muscle C2C12 cells, representative of cardiac and skeletal muscle respectively. Consistent with previous data on molecular patterns, electrophysiological and Ca2+-handling properties of ?SG?/? cMabs were closer to C2C12 cells than to CM ones. Nevertheless, subtler aspects, including action potential contour, Ca2+-spark properties and RyR isoform expression, distinguished ?SG?/? cMabs from C2C12 cells. Contrary to previous reports, wild-type cMabs failed to show functional differentiation towards either cell type. Knock-in of miRNA669a in ?SG?/? cMabs rescued the wild-type functional phenotype, i.e. it completely prevented development of skeletal muscle functional responses. We conclude that miRNA669a expression, ablated by ?SG deletion, may prevent functional differentiation of cMabs towards the skeletal muscle phenotype. PMID:23387296

Altomare, Claudia; Barile, Lucio; Rocchetti, Marcella; Sala, Luca; Crippa, Stefania; Sampaolesi, Maurilio; Zaza, Antonio

2013-01-01

86

Differential approach to the memory-function reaction kinetics  

NASA Astrophysics Data System (ADS)

A new formulation of the encounter theory for liquid-phase many-particle reacting systems (MPRS) is developed. This new formulation is based upon the notion of the pair distribution function and results in a set of partial differential equations equivalent to the integro-differential equations of the conventional approach. The solution is greatly improved by considering pair-particle interactions. The new formulation is applicable to arbitrary MPRS and allows for a general numerical solution. Applied to the Lotka-Volterra reaction, this approach revealed damping and increasing oscillations on the concentration, which cannot be seen in the framework of phenomenological chemical kinetics.

Frantsuzov, P. A.; Igoshin, O. A.; Krissinel, E. B.

2000-02-01

87

Limited role of functional differentiation in early diversification of animals  

PubMed Central

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

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

2015-01-01

88

Differential Impact of Parent Functioning on Infant Social Emotional Functioning During the Transition to Parenthood  

E-print Network

? involvement (McBride, Schoppe- Sullivan, & Ho, 2005). Another study examined the differential importance of having two supportive parents, one supportive parent or two non-supportive parents in predicting cognitive outcomes in cognitive functioning (Ryan...

Carhart, Kathryn Patricia

2012-07-16

89

Differentiable but exact formulation of density-functional theory  

SciTech Connect

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 ? > 0, pairs of conjugate functionals ({sup ?}E, {sup ?}F) that converge to (E, F) pointwise everywhere as ? ? 0{sup +}, and such that {sup ?}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 ?}E(v) in a simple way. All concepts and results pertaining to the original (E, F) pair have direct counterparts in results for ({sup ?}E, {sup ?}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 ?}F, a rigorous formulation of Kohn–Sham theory is presented that does not suffer from the noninteracting representability problem in standard Kohn–Sham theory.

Kvaal, Simen, E-mail: simen.kvaal@kjemi.uio.no; Ekström, Ulf; Helgaker, Trygve [Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo (Norway)] [Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo (Norway); Teale, Andrew M. [Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo (Norway) [Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo (Norway); School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom)

2014-05-14

90

14 CFR 23.1163 - Powerplant accessories.  

Code of Federal Regulations, 2011 CFR

...2) of this section, be sealed to prevent contamination of the engine oil system and the accessory system. ...mounting; and (3) Be sealed to prevent contamination of the gearbox oil system and the accessory system....

2011-01-01

91

14 CFR 23.1163 - Powerplant accessories.  

Code of Federal Regulations, 2013 CFR

...2) of this section, be sealed to prevent contamination of the engine oil system and the accessory system. ...mounting; and (3) Be sealed to prevent contamination of the gearbox oil system and the accessory system....

2013-01-01

92

14 CFR 23.1163 - Powerplant accessories.  

Code of Federal Regulations, 2010 CFR

...2) of this section, be sealed to prevent contamination of the engine oil system and the accessory system. ...mounting; and (3) Be sealed to prevent contamination of the gearbox oil system and the accessory system....

2010-01-01

93

14 CFR 23.1163 - Powerplant accessories.  

Code of Federal Regulations, 2012 CFR

...2) of this section, be sealed to prevent contamination of the engine oil system and the accessory system. ...mounting; and (3) Be sealed to prevent contamination of the gearbox oil system and the accessory system....

2012-01-01

94

14 CFR 23.1163 - Powerplant accessories.  

Code of Federal Regulations, 2014 CFR

...2) of this section, be sealed to prevent contamination of the engine oil system and the accessory system. ...mounting; and (3) Be sealed to prevent contamination of the gearbox oil system and the accessory system....

2014-01-01

95

21 CFR 890.3910 - Wheelchair accessory.  

Code of Federal Regulations, 2012 CFR

...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910 Wheelchair accessory. (a) Identification. A wheelchair accessory is a device...

2012-04-01

96

21 CFR 890.3910 - Wheelchair accessory.  

Code of Federal Regulations, 2011 CFR

...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910 Wheelchair accessory. (a) Identification. A wheelchair accessory is a device...

2011-04-01

97

Electrical recordings from the accessory olfactory bulb in VNO-AOB ex vivo preparations.  

PubMed

Electrical recordings from individual accessory olfactory bulb neurons allow exploration of the functional properties of this important pheromonal processing circuit. Several approaches to performing such recordings have been used. Here, we describe ex vivo methods that we have found useful for recording from accessory olfactory bulb neurons using simple extracellular glass electrodes. PMID:24014366

Meeks, Julian P; Holy, Timothy E

2013-01-01

98

WagTag: A Dog Collar Accessory for Monitoring Canine Activity Levels  

E-print Network

accessories with such apps are now emerging for the pet market. In this paper we describe WagTag, an accessory with the development of this device, especially with respect to aesthetics, durability, and functionality, and also@cis.fordham.edu Ashwin Nathan Healthy Pet Technologies Cincinnati, OH, 45202 winash@gmail.com JB Kropp Healthy Pet

Weiss, Gary

99

Rax regulates hypothalamic tanycyte differentiation and barrier function in mice.  

PubMed

The wall of the ventral third ventricle is composed of two distinct cell populations: tanycytes and ependymal cells. Tanycytes regulate many aspects of hypothalamic physiology, but little is known about the transcriptional network that regulates their development and function. We observed that the retina and anterior neural fold homeobox transcription factor (Rax) is selectively expressed in hypothalamic tanycytes, and showed a complementary pattern of expression to markers of hypothalamic ependymal cells, such as Rarres2 (retinoic acid receptor responder [tazarotene induced] 2). To determine whether Rax controls tanycyte differentiation and function, we generated Rax haploinsufficient mice and examined their cellular and molecular phenotype in adulthood. These mice appeared grossly normal, but careful examination revealed a thinning of the third ventricular wall and reduction of both tanycyte and ependymal markers. These experiments show that Rax is required for hypothalamic tanycyte and ependymal cell differentiation. Rax haploinsufficiency also resulted in the ectopic presence of ependymal cells in the ?2 tanycytic zone, where few ependymal cells are normally found, suggesting that Rax is selectively required for ?2 tanycyte differentiation. These changes in the ventricular wall were associated with reduced diffusion of Evans Blue tracer from the ventricle to the hypothalamic parenchyma, with no apparent repercussion on the gross anatomical or behavioral phenotype of these mice. In conclusion, we have provided evidence that Rax is required for the normal differentiation and patterning of hypothalamic tanycytes and ependymal cells, as well as for maintenance of the cerebrospinal fluid-hypothalamus barrier. PMID:23939786

Miranda-Angulo, Ana L; Byerly, Mardi S; Mesa, Janny; Wang, Hong; Blackshaw, Seth

2014-03-01

100

Rax regulates hypothalamic tanycyte differentiation and barrier function in mice  

PubMed Central

The wall of the ventral third ventricle is composed of two distinct cell populations: tanycytes and ependymal cells. Tanycytes regulate many aspects of hypothalamic physiology, but little is known about the transcriptional network that regulates their development and function. We observed that the retina and anterior neural fold homeobox transcription factor (Rax) is selectively expressed in hypothalamic tanycytes, and showed a complementary pattern of expression to markers of hypothalamic ependymal cells, such as Rarres2 (retinoic acid receptor responder). To determine whether Rax controls tanycyte differentiation and function, we generated Rax haploinsufficient mice and examined their cellular and molecular phenotype in adulthood. These mice appeared grossly normal, but careful examination revealed a thinning of the third ventricular wall and reduction of both tanycyte and ependymal markers. These experiments show that Rax is required for hypothalamic tanycyte and ependymal cell differentiation. Rax haploinsufficiency also resulted in the ectopic presence of ependymal cells in the ?2 tanycytic zone, where few ependymal cells are normally found, suggesting that Rax is selectively required for ?2 tanycyte differentiation. These changes in the ventricular wall were associated with reduced diffusion of Evans Blue tracer from the ventricle to the hypothalamic parenchyma, with no apparent repercussion on the gross anatomical or behavioral phenotype of these mice. In conclusion, we have provided evidence that Rax is required for the normal differentiation and patterning of hypothalamic tanycytes and ependymal cells, as well as for maintenance of the cerebrospinal fluid-hypothalamus barrier. PMID:23939786

Miranda-Angulo, Ana L.; Byerly, Mardi S.; Mesa, Janny; Wang, Hong; Blackshaw, Seth

2013-01-01

101

Inorganic arsenic impairs differentiation and functions of human dendritic cells  

SciTech Connect

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-? 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 ?M) 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 ?M) 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-? 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 ?M) blocks differentiation of dendritic cells by inducing necrosis ? Arsenite (0.1 to 0.5 ?M) slightly reduces endocytotic activity of immature DCs ? Arsenite (0.1 to 0.5 ?M) represses expression of IL-12p70 and IL-23 in activated DCs ? Arsenite (0.1 to 0.5 ?M) reduces the ability of DCs to activate human T lymphocytes.

Macoch, Mélinda; Morzadec, Claudie [UMR INSERM U1085, Institut de Recherche sur la Santé, l'Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France)] [UMR INSERM U1085, Institut de Recherche sur la Santé, l'Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Fardel, Olivier [UMR INSERM U1085, Institut de Recherche sur la Santé, l'Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France) [UMR INSERM U1085, Institut de Recherche sur la Santé, l'Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Pôle Biologie, Centre Hospitalier Universitaire (CHU) Rennes, 2 rue Henri Le Guilloux, 35033 Rennes (France); Vernhet, Laurent, E-mail: laurent.vernhet@univ-rennes1.fr [UMR INSERM U1085, Institut de Recherche sur la Santé, l'Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France)] [UMR INSERM U1085, Institut de Recherche sur la Santé, l'Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France)

2013-01-15

102

Exp-Function Method for Solving Fractional Partial Differential Equations  

PubMed Central

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. PMID:23818823

2013-01-01

103

Glucose metabolism regulates T cell activation, differentiation, and functions.  

PubMed

The adaptive immune system is equipped to eliminate both tumors and pathogenic microorganisms. It requires a series of complex and coordinated signals to drive the activation, proliferation, and differentiation of appropriate T cell subsets. It is now established that changes in cellular activation are coupled to profound changes in cellular metabolism. In addition, emerging evidence now suggest that specific metabolic alterations associated with distinct T cell subsets may be ancillary to their differentiation and influential in their immune functions. The "Warburg effect" originally used to describe a phenomenon in which most cancer cells relied on aerobic glycolysis for their growth is a key process that sustain T cell activation and differentiation. Here, we review how different aspects of metabolism in T cells influence their functions, focusing on the emerging role of key regulators of glucose metabolism such as HIF-1?. A thorough understanding of the role of metabolism in T cell function could provide insights into mechanisms involved in inflammatory-mediated conditions, with the potential for developing novel therapeutic approaches to treat these diseases. PMID:25657648

Palmer, Clovis S; Ostrowski, Matias; Balderson, Brad; Christian, Nicole; Crowe, Suzanne M

2015-01-01

104

47 CFR 15.27 - Special accessories.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Special accessories. 15.27 Section 15.27 Telecommunication...DEVICES General § 15.27 Special accessories. (a) Equipment marketed...equipment is marketed. Where special accessories, such as shielded cables...

2010-10-01

105

Teaching Techniques for Accessory Percussion  

ERIC Educational Resources Information Center

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…

Micallef, Ken

2007-01-01

106

news update Fashion Accessory Design  

E-print Network

news update let's talk Fashion Accessory Design Fashion Design Fashion Knitwear Design and Knitted in the fashion and textile industry. Through Texprint, Alice will receive mentoring and benefit from being and fashion fabrics. Following an exhibition in London, Alice will have her own stand at the Texprint Village

Evans, Paul

107

The extensive set of accessory Pseudomonas aeruginosa genomic components.  

PubMed

Up to 20% of the chromosomal Pseudomonas aeruginosa DNA belong to the so-called accessory genome. Its elements are specific for subgroups or even single strains and are likely acquired by horizontal gene transfer (HGT). Similarities of the accessory genomic elements to DNA from other bacterial species, mainly the DNA of ?- and ?-proteobacteria, indicate a role of interspecies HGT. In this study, we analysed the expression of the accessory genome in 150 clinical P. aeruginosa isolates as uncovered by transcriptome sequencing and the presence of accessory genes in eleven additional isolates. Remarkably, despite the large number of P. aeruginosa strains that have been sequenced to date, we found new strain-specific compositions of accessory genomic elements and a high portion (10-20%) of genes without P. aeruginosa homologues. Although some genes were detected to be expressed/present in several isolates, individual patterns regarding the genes, their functions and the possible origin of the DNA were widespread among the tested strains. Our results demonstrate the unaltered potential to discover new traits within the P. aeruginosa population and underline that the P. aeruginosa pangenome is likely to increase with increasing sequence information. PMID:24766399

Pohl, Sarah; Klockgether, Jens; Eckweiler, Denitsa; Khaledi, Ariane; Schniederjans, Monika; Chouvarine, Philippe; Tümmler, Burkhard; Häussler, Susanne

2014-07-01

108

Increase in the number of tyrosine hydroxylase-containing neurons in a primary culture system of the rat accessory olfactory bulb by co-culture with vomeronasal pockets  

Microsoft Academic Search

Previously, we established a culture system of the accessory olfactory bulb in order to investigate the functional role of each accessory olfactory bulb neurons in pheromonal signal processing. In the present study, we developed a co-culture system of cultured accessory olfactory bulb neurons with partially dissociated cells of the vomeronasal organ. The dissociated cells of the vomeronasal organ form spherical

K Muramoto; T Osada; M Kato-Negishi; Y Kuroda; M Ichikawa

2003-01-01

109

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

ERIC Educational Resources Information Center

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)

Zwick, Rebecca

1990-01-01

110

Norepinephrine transporter expression and function in noradrenergic cell differentiation.  

PubMed

The classical view of norepinephrine transporter (NET) function is the re-uptake of released norepinephrine (NE) by mature sympathetic neurons and noradrenergic neurons of the locus ceruleus (LC; [1-3]). In this report we review previous data and present new results that show that NET is expressed in the young embryo in a wide range of neuronal and non-neuronal tissues and that NET has additional functions during embryonic development. Sympathetic neurons are derived from neural crest stem cells. Fibroblast growth factor-2 (FGF-2), neurotrophin-3 (NT-3) and transforming growth factor-beta1 (TGF-beta1) regulate NET expression in cultured quail neural crest cells by causing an increase in NET mRNA levels. They also promote NET function in both neural crest cells and presumptive noradrenergic cells of the LC. The growth factors are synthesized by the neural crest cells and therefore are likely to have autocrine function. In a subsequent stage of development, NE transport regulates differentiation of noradrenergic neurons in the peripheral nervous system and the LC by promoting expression of tyrosine hydroxylase (TH) and dopamine-beta-hydroxylase (DBH). Conversely, uptake inhibitors, such as the tricyclic antidepressant, desipramine, and the drug of abuse, cocaine, inhibit noradrenergic differentiation in both tissues. Taken together, our data indicate that NET is expressed early in embryonic development, NE transport is involved in regulating expression of the noradrenergic phenotype in the peripheral and central nervous systems, and norepinephrine uptake inhibitors can disturb noradrenergic cell differentiation in the sympathetic ganglion (SG) and LC. PMID:11108137

Sieber-Blum, M; Ren, Z

2000-09-01

111

Exploration of the Validity of Gender Differences in Mathematics Assessment Using Differential Bundle Functioning  

ERIC Educational Resources Information Center

The aims of this study are (a) to examine the sources of differential functioning by gender via differential bundle functioning (DBF) in mathematics assessment and (b) to use DBF to explore whether the differential functioning displayed is construct-relevant or construct-irrelevant. Three qualitatively different areas, namely curriculum domains,…

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

2011-01-01

112

Risedronate increases osteoblastic differentiation and function through connexin43.  

PubMed

Bisphosphonates are potent antiresorptive drugs which have antifracture efficacy by reducing bone turnover rate and increasing bone mineral density. In addition to inhibiting osteoclast function, bisphosphonates have been reported to also promote survival of osteocyte and osteoblast via an anti-apoptotic effect, mediated by opening of hemi-gap junction channels formed by connexin43 (Cx43). In this study, we investigated the effect of risedronate, one amino-bisphosphonate, on osteoblast differentiation and Cx43 expression using the mesenchymal cell line C2C12. Risedronate dose-dependently increased the activity of osterix (OSE)-luciferase containing Runx2 response element with highest activity at 50?M. The activity of osteocalcin (OC)- and bone sialoprotein (BSP)-luciferase reporters, markers of osteoblast differentiation, were also increased by risedronate. When risedronate and BMP2 were used in combination, alkaline phosphatase (ALP) activity increased to a larger extent than when BMP2 was used alone. Risedronate as well as the pro-osteogenic transcription factors, Runx2, Osterix or Dlx5, increased transcriptional activity of the Cx43 promoter in a dose-dependent manner. In the presence of Runx2 or Dlx5, risedronate had an additive effect on Cx43 promoter activity. Accordingly, risedronate increased protein expression of Cx43, Runx2, Osterix, and Dlx5. These results suggest that risedronate promotes osteoblastic differentiation and positively regulates Cx43 gene transcription. PMID:23376077

Jeong, Hyung Min; Jin, Yun-Hey; Choi, You-Hee; Chung, Jin Ook; Cho, Dong Hyeok; Chung, Min Young; Civitelli, Roberto; Chung, Dong Jin; Lee, Kwang Youl

2013-03-01

113

Modification of accessory molecule signaling  

Microsoft Academic Search

The concept of costimulation, the requirement for an independent accessory cellular activation signal that supplements the\\u000a signal delivered to a lymphocyte by antigen, has been a focal point of progress in understanding the regulation of the immune\\u000a system. While considerable attention has been directed to new developments related to the activation of cells of the innate\\u000a immune system through Toll-like

Mary K. Crow; Springer Semin

2006-01-01

114

The Epigenetic Landscape of Mammary Gland Development and Functional Differentiation  

PubMed Central

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 conformation initiated by DNA methylation, histone variants, post-translational modifications of histones, non-histone chromatin proteins, and non-coding RNAs. Epigenetics plays a key role in development. However, very little is known about its role in the developing mammary gland or how it might integrate the many signalling pathways involved in mammary gland development and function that have been discovered during the past few decades. An inverse relationship between marks of closed (DNA methylation) or open chromatin (DnaseI hypersensitivity, certain histone modifications) and milk protein gene expression has been documented. Recent studies have shown that during development and functional differentiation, both global and local chromatin changes occur. Locally, chromatin at distal regulatory elements and promoters of milk protein genes gains a more open conformation. Furthermore, changes occur both in looping between regulatory elements and attachment to nuclear matrix. These changes are induced by developmental signals and environmental conditions. Additionally, distinct epigenetic patterns have been identified in mammary gland stem and progenitor cell sub-populations. Together, these findings suggest that epigenetics plays a role in mammary development and function. With the new tools for epigenomics developed in recent years, we now can begin to establish a framework for the role of epigenetics in mammary gland development and disease. PMID:20157770

Rijnkels, Monique; Kabotyanski, Elena; Montazer-Torbati, Mohamad B.; Beauvais, C. Hue; Vassetzky, Yegor; Rosen, Jeffrey M.; Devinoy, Eve

2010-01-01

115

Envy: Functional specificity and sex-differentiated design features Danielle J. DelPriore a,  

E-print Network

Envy: Functional specificity and sex-differentiated design features Danielle J. DelPriore a processing (e.g., Hill et al., 2011), many hypotheses derived from the model ­ particularly those about sex-differentiation? (b) is envy a sex-differentiated emotion? 1.1. The contexts of envy: sex-differentiated by design

Pillow, Jonathan

116

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

Code of Federal Regulations, 2014 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4960 Operating tables and accessories and operating chairs and accessories....

2014-04-01

117

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

Code of Federal Regulations, 2012 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4960 Operating tables and accessories and operating chairs and accessories....

2012-04-01

118

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

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4960 Operating tables and accessories and operating chairs and accessories....

2013-04-01

119

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

Code of Federal Regulations, 2011 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4960 Operating tables and accessories and operating chairs and accessories....

2011-04-01

120

21 CFR 890.5925 - Traction accessory.  

Code of Federal Regulations, 2011 CFR

...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory. (a) Identification. A...

2011-04-01

121

21 CFR 890.3910 - Wheelchair accessory.  

Code of Federal Regulations, 2014 CFR

...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910 Wheelchair accessory. (a) Identification. A...

2014-04-01

122

21 CFR 890.5925 - Traction accessory.  

Code of Federal Regulations, 2013 CFR

...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory. (a) Identification. A...

2013-04-01

123

21 CFR 890.3910 - Wheelchair accessory.  

Code of Federal Regulations, 2010 CFR

...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910 Wheelchair accessory. (a) Identification. A...

2010-04-01

124

21 CFR 890.5925 - Traction accessory.  

Code of Federal Regulations, 2014 CFR

...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory. (a) Identification. A...

2014-04-01

125

21 CFR 890.5925 - Traction accessory.  

Code of Federal Regulations, 2010 CFR

...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory. (a) Identification. A...

2010-04-01

126

21 CFR 890.5925 - Traction accessory.  

Code of Federal Regulations, 2012 CFR

...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory. (a) Identification. A...

2012-04-01

127

Engine starter and accessory drive system  

SciTech Connect

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.

Stockton, T.R.

1986-10-07

128

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...

129

Differential item functioning analysis by applying multiple comparison procedures.  

PubMed

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. PMID:25562333

Eusebi, Paolo; Kreiner, Svend

2015-01-01

130

MicroRNA control of lymphocyte differentiation and function  

PubMed Central

Summary MicroRNAs (miRNAs) are a class of endogenous, non-coding regulatory RNAs that control gene regulation by guiding silencing protein complexes to mRNA in a sequence-dependent manner. In this way miRNAs are able to repress gene expression post-transcriptionally by affecting mRNA stability or translation. These ubiquitous molecules play central roles in a wide range of biological processes, including cell proliferation, differentiation and apoptosis. Within the context of the immune system, genetic studies have identified distinct roles for specific miRNAs in gene regulation during development, activation and maturation. Conversely, dysregulation of miRNA expression has been specifically correlated with cancer. This review outlines our current understanding of miRNA function in lymphocytes as it impacts expression of protein-coding genes in the context of proper development, as well as oncogenesis. PMID:21353514

Belver, Laura; Papavasiliou, Nina F; Ramiro, Almudena R

2011-01-01

131

Modifying Measures Based on Differential Item Functioning (DIF) Impact Analyses  

PubMed Central

Objectives Measure modification can impact comparability of scores across groups and settings. Changes in items can affect the percent admitting to a symptom. Methods Using item response theory (IRT) methods, well-calibrated items can be used interchangeably, and the exact same item does not have to be administered to each respondent, theoretically permitting wider latitude in terms of modification. Results Recommendations regarding modifications vary, depending on the use of the measure. In the context of research, adjustments can be made at the analytic level by freeing and fixing parameters based on findings of differential item functioning (DIF). The consequences of DIF for clinical decision making depend on whether or not the patient’s performance level approaches the scale decision cutpoint. High-stakes testing may require item removal or separate calibrations to ensure accurate assessment. Discussion Guidelines for modification based on DIF analyses and illustrations of the impact of adjustments are presented. PMID:22422759

Teresi, Jeanne A.; Ramirez, Mildred; Jones, Richard N.; Choi, Seung; Crane, Paul K.

2014-01-01

132

The sea lamprey has a primordial accessory olfactory system  

PubMed Central

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

2013-01-01

133

Accessory cells in the immune defense of the dental pulp.  

PubMed

This communication focuses on the participation of accessory cells in the initial recognition and processing of antigenic substances in the dental pulp. Immunohistochemical analyses have demonstrated the presence of two types of accessory cells--one with a dendritic morphology located in the periphery of the pulp and one with a macrophage-like appearance located more centrally. Functional studies in vitro have provided evidence for the dendritic cells being the most significant of the two cells regarding their capacity to induce T-cell proliferation. Studies on ontogeny have revealed that the appearance of pulp accessory cells is delayed compared to other peripheral tissues. In experimentally induced pulp lesions a rapid increase of cells with morphologic and phenotypic features similar to normally occurring accessory cells was found. These data demonstrate that the dental pulp contains the necessary cellular constituents to mount an immunologic defense reaction. Future studies should focus on elucidating possible interactions between these immune cells and the neurovascular system of the pulp. PMID:1508890

Jontell, M; Bergenholtz, G

1992-01-01

134

Differential regulation of cell functions by CSD peptide subdomains  

PubMed Central

Background In fibrotic lung diseases, expression of caveolin-1 is decreased in fibroblasts and monocytes. The effects of this deficiency are reversed by treating cells or animals with the caveolin-1 scaffolding domain peptide (CSD, amino acids 82–101 of caveolin-1) which compensates for the lack of caveolin-1. Here we compare the function of CSD subdomains (Cav-A, Cav-B, Cav-C, Cav-AB, and Cav-BC) and mutated versions of CSD (F92A and T90A/T91A/F92A). Methods Migration toward the chemokine CXCL12 and the associated expression of F-actin, CXCR4, and pSmad 2/3 were studied in monocytes from healthy donors and SSc patients. Fibrocyte differentiation was studied using PBMC from healthy donors and SSc patients. Collagen I secretion and signaling were studied in fibroblasts derived from the lung tissue of healthy subjects and SSc patients. Results Cav-BC and CSD at concentrations as low as 0.01 ?M inhibited the hypermigration of SSc monocytes and TGF?-activated Normal monocytes and the differentiation into fibrocytes of SSc and Normal monocytes. While CSD also inhibited the migration of poorly migrating Normal monocytes, Cav-A (and other subdomains to a lesser extent) promoted the migration of Normal monocytes while inhibiting the hypermigration of TGF?-activated Normal monocytes. The effects of versions of CSD on migration may be mediated in part via their effects on CXCR4, F-actin, and pSmad 2/3 expression. Cav-BC was as effective as CSD in inhibiting fibroblast collagen I and ASMA expression and MEK/ERK signaling. Cav-C and Cav-AB also inhibited collagen I expression, but in many cases did not affect ASMA or MEK/ERK. Cav-A increased collagen I expression in scleroderma lung fibroblasts. Full effects on fibroblasts of versions of CSD required 5 ?M peptide. Conclusions Cav-BC retains most of the anti-fibrotic functions of CSD; Cav-A exhibits certain pro-fibrotic functions. Results obtained with subdomains and mutated versions of CSD further suggest that the critical functional residues in CSD depend on the cell type and readout being studied. Monocytes may be more sensitive to versions of CSD than fibroblasts and endothelial cells because the baseline level of caveolin-1 in monocytes is much lower than in these other cell types. PMID:24011378

2013-01-01

135

Advanced Accessory Power Supply Topologies  

SciTech Connect

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. Two studies were conducted at ORNL. One was to put an additional winding in the motor slots to magnetically link with the high frequency of the controllable zero-sequence stator currents that do not produce any zero-sequence harmonic torques. The second approach was to utilize the corners of the square stator punching for the high-frequency transformers of the dc/dc inverter. Both approaches were successful. This CRADA validated the feasibility of GM’s desire to use the motor’s magnetic core and windings to produce bidirectional accessory power supply. Three joint U.S. patents with GM were issued to ORNL and GM by the U.S. Patent Office for the research results produced by this CRADA.

Marlino, L.D.

2010-06-15

136

21 CFR 872.3980 - Endosseous dental implant accessories.  

Code of Federal Regulations, 2014 CFR

... Endosseous dental implant accessories. 872...DEVICES DENTAL DEVICES Prosthetic Devices § 872.3980 Endosseous dental implant accessories. (a... Endosseous dental implant accessories are manually...of endosseous dental implants and abutments,...

2014-04-01

137

21 CFR 872.3980 - Endosseous dental implant accessories.  

Code of Federal Regulations, 2012 CFR

... Endosseous dental implant accessories. 872...DEVICES DENTAL DEVICES Prosthetic Devices § 872.3980 Endosseous dental implant accessories. (a... Endosseous dental implant accessories are manually...of endosseous dental implants and abutments,...

2012-04-01

138

21 CFR 872.3980 - Endosseous dental implant accessories.  

Code of Federal Regulations, 2010 CFR

... Endosseous dental implant accessories. 872...DEVICES DENTAL DEVICES Prosthetic Devices § 872.3980 Endosseous dental implant accessories. (a... Endosseous dental implant accessories are manually...of endosseous dental implants and abutments,...

2010-04-01

139

21 CFR 872.6300 - Rubber dam and accessories.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Rubber dam and accessories. 872.6300 Section 872...Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device...

2011-04-01

140

21 CFR 872.6300 - Rubber dam and accessories.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Rubber dam and accessories. 872.6300 Section 872...Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device...

2014-04-01

141

21 CFR 872.6300 - Rubber dam and accessories.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Rubber dam and accessories. 872.6300 Section 872...Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device...

2013-04-01

142

21 CFR 872.6300 - Rubber dam and accessories.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Rubber dam and accessories. 872.6300 Section 872...Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device...

2012-04-01

143

21 CFR 870.4200 - Cardiopulmonary bypass accessory equipment.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Cardiopulmonary bypass accessory equipment. 870.4200 Section...870.4200 Cardiopulmonary bypass accessory equipment. (a) Identification. Cardiopulmonary bypass accessory equipment is a device that...

2010-04-01

144

21 CFR 884.4900 - Obstetric table and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Obstetric table and accessories. 884.4900 Section 884.4900... § 884.4900 Obstetric table and accessories. (a) Identification. An...type of device may include the following accessories: patient equipment, support...

2010-04-01

145

14 CFR 121.251 - Engine accessory section diaphragm.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Engine accessory section diaphragm. 121.251 Section...Airworthiness Requirements § 121.251 Engine accessory section diaphragm. Unless equivalent...of the exhaust system from the engine accessory...

2010-01-01

146

49 CFR 393.3 - Additional equipment and accessories.  

Code of Federal Regulations, 2010 CFR

...false Additional equipment and accessories. 393.3 Section 393.3...SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION...3 Additional equipment and accessories. Nothing contained in...

2010-10-01

147

21 CFR 868.5860 - Pressure tubing and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Pressure tubing and accessories. 868.5860 Section 868.5860... § 868.5860 Pressure tubing and accessories. (a) Identification. Pressure tubing and accessories are flexible or rigid devices...

2010-04-01

148

21 CFR 872.4200 - Dental handpiece and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Dental handpiece and accessories. 872.4200 Section 872.4200...872.4200 Dental handpiece and accessories. (a) Identification. A dental handpiece and accessories is an AC-powered,...

2010-04-01

149

14 CFR 125.149 - Engine accessory section diaphragm.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Engine accessory section diaphragm. 125.149 Section...Airworthiness Requirements § 125.149 Engine accessory section diaphragm. Unless equivalent...of the exhaust system from the engine accessory...

2010-01-01

150

21 CFR 884.2640 - Fetal phonocardiographic monitor and accessories.  

Code of Federal Regulations, 2010 CFR

...Fetal phonocardiographic monitor and accessories. 884.2640 Section 884.2640...Fetal phonocardiographic monitor and accessories. (a) Identification. A...type of device includes the following accessories: signal analysis and display...

2010-04-01

151

21 CFR 872.6250 - Dental chair and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Dental chair and accessories. 872.6250 Section 872.6250...Devices § 872.6250 Dental chair and accessories. (a) Identification. A dental chair and accessories is a device, usually...

2010-04-01

152

21 CFR 872.4120 - Bone cutting instrument and accessories.  

Code of Federal Regulations, 2010 CFR

...false Bone cutting instrument and accessories. 872.4120 Section 872.4120...4120 Bone cutting instrument and accessories. (a) Identification. A bone cutting instrument and accessories is a metal device...

2010-04-01

153

49 CFR 192.147 - Flanges and flange accessories.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Flanges and flange accessories. 192.147 Section 192.147 Transportation...Components § 192.147 Flanges and flange accessories. (a) Each flange or flange accessory (other than cast iron) must meet...

2010-10-01

154

21 CFR 884.4120 - Gynecologic electrocautery and accessories.  

Code of Federal Regulations, 2010 CFR

...false Gynecologic electrocautery and accessories. 884.4120 Section 884.4120...4120 Gynecologic electrocautery and accessories. (a) Identification. ...of device may include the following accessories: an electrical generator, a...

2010-04-01

155

Ordinary Differential Equations -Check your knowledge Do you know how to decide whether a function is a solution to a differential equation?  

E-print Network

Ordinary Differential Equations - Check your knowledge Do you know how to decide whether a function is a solution to a differential equation? Do you know how to find a solution to a differential a differential equation is linear? Same question with a system of differential equations. Do you know how

Lega, Joceline

156

Three Accessories for a Rotating Platform.  

ERIC Educational Resources Information Center

Describes three accessories developed to be used in conjunction with the rotating platform or turntable. Three demonstrations using these accessories are included. These demonstrations are: (a) conservation of angular momentum; (b) gravity-defying goblets; and (c) direct measurement of centripetal force. (HM)

Riley, James A.; Fryer, Oscar G.

1980-01-01

157

An accessory limb with an imperforate anus  

PubMed Central

Congenital accessory limbs are very rare anomalies with many causative factors. We describe the case of a 1-day-old female neonate-born to a healthy, 27-year-old mother-who presented with an accessory limb (foot) attached to the buttock and an imperforate anus. We also provide a review of the relevant literature. PMID:25317418

Park, Kun-Bo; Kim, Yeon-Mee; Park, Ji-Yong; Chung, Mi-Lim; Jung, Yu-Jin

2014-01-01

158

Gas turbine engine with convertible accessories  

NASA Technical Reports Server (NTRS)

Drive means for connecting a gas turbine engine to its accessories are so constructed as to allow the accessories to be selectively positioned to any one of several predetermined circumferential positions about the perimeter of the engine. This feature permits convenient mounting of the same engine upon vehicles demanding radically different engine mounting arrangements.

Sargisson, D. F.; Adamson, A. P. (inventors)

1978-01-01

159

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

ERIC Educational Resources Information Center

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…

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

2010-01-01

160

Differential localization and functional role of calsequestrin in growing and differentiated myoblasts  

PubMed Central

Calsequestrin (CSQ) is the low affinity, high capacity Ca(2+)-binding protein concentrated within specialized areas of the muscle fiber sarcoplasmic reticulum (a part of the ER) where it is believed to buffer large amounts of Ca2+. Upon activation of intracellular channels this Ca2+ pool is released, giving rise to the [Ca2+]i increases that sustain contraction. In order to investigate the ER retention and the functional role of the protein, L6 rat myoblasts were infected with a viral vector with or without the cDNA of chicken CSQ, and stable clones were investigated before and after differentiation to myotubes. In the undifferentiated L6 cells, expression of considerable amounts of heterologous CSQ occurred with no major changes of other ER components. Ca2+ release from the ER, induced by the peptide hormone vasopressin, remained however unchanged, and the same occurred when other treatments were given in sequence to deplete the ER and other intracellular stores: with the Ca2+ pump blocker, thapsigargin; and with the Ca2+ ionophore, ionomycin, followed by the Na+/H+ ionophore, monensin. The lack of effect of CSQ expression on the vasopressin-induced [Ca2+]i responses was explained by immunocytochemistry showing the heterologous protein to be localized not in the ER but in large vacuoles of acidic content, positive also for the lysosomal enzyme, cathepsin D, corresponding to a lysosomal subpopulation. After differentiation, all L6 cells expressed small amounts of homologous CSQ. In the infected cells the heterologous protein progressively decreased, yet the [Ca2+]i responses to vasopressin were now larger with respect to both control and undifferentiated cells. This change correlated with the drop of the vacuoles and with the accumulation of CSQ within the ER lumen, where a clustered distribution was observed as recently shown in developing muscle fibers. These results provide direct evidence for the contribution of CSQ, when appropriately retained, to the Ca2+ capacity of the rapidly exchanging, ER-located Ca2+ stores; and for the existence of specific mechanism(s) (that in L6 cells develop in the course of differentiation) for the ER retention of the protein. In the growing L6 myoblasts the Ca(2+)-binding protein appears in contrast to travel along the exocytic pathway, down to post-Golgi, lysosome-related vacuoles which, based on the lack of [Ca2+]i response to ionomycin- monensin, appear to be incompetent for Ca2+ accumulation. PMID:7844148

1995-01-01

161

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

PubMed

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. PMID:9436838

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

1997-01-01

162

Accessory and stimulating properties of dendritic cells and macrophages isolated from various rat tissues  

PubMed Central

Single cell suspensions of rat lymphoid and nonlymphoid tissues were fractionated on discontinuous gradients of bovine serum albumin into high density and low density subfractions. In general, accessory activity required for responses of periodate-treated T lymphocytes was recovered only in a low density population containing a small percent of the total fractionated cells from lymph nodes, spleen, liver, skin, and peritoneal exudates. Further purification always led to an increase of both accessory activity and number of dendritic cells present in nonrosetting and nonadherent populations. After purification, a high recovery of the total accessory activity was found in fractions that contained a high percentage of dendritic cells resulting in a more than 1,000-fold enrichment in accessory activity per cell. No other fraction obtained during the purification contained significant accessory activity. In all cases, macrophage-enriched populations lacked accessory cell activity. With the exception of peritoneal exudate cell preparations, which contained an inhibitory cell, the level of accessory activity in a given population was always found to be a function of the number of dendritic cells present. Dendritic cells from all sources were nonadherent, nonphagocytic, radio- resistant, and nonspecific esterase negative. They expressed Ia antigens and lacked Fc receptors. Both epidermal and lymph node dendritic cells contain Birbeck granules, subcellular structures previously described only for Langerhans cells. Accessory activity requires viable dendritic cells but is unaffected by 1,000 rad of ?-irradiation. However, ultraviolet irradiation abolished the activity of accessory cells. The cells that responded to periodate were IgG-negative T cells, whereas IgG-positive B cells could not be stimulated under the same conditions. Only periodate-treated T cells and dendritic cells were needed for responses to occur; removal of virtually all macrophages from these purified preparations had no effect. Dendritic cells were also required as stimulators in mixed leukocyte cultures, whereas macrophages, even though Ia positive, were inert. PMID:6211498

Klinkert, WEF; LaBadie, JH; Bowers, WE

1982-01-01

163

Functional differentiation of cytotoxic cancer drugs and targeted cancer therapeutics.  

PubMed

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. PMID:24956585

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

2014-10-01

164

GO-Diff: Mining functional differentiation between EST-based transcriptomes  

Microsoft Academic Search

BACKGROUND: Large-scale sequencing efforts produced millions of Expressed Sequence Tags (ESTs) collectively representing differentiated biochemical and functional states. Analysis of these EST libraries reveals differential gene expressions, and therefore EST data sets constitute valuable resources for comparative transcriptomics. To translate differentially expressed genes into a better understanding of the underlying biological phenomena, existing microarray analysis approaches usually involve the integration

Zuozhou Chen; Weilin Wang; Xuefeng Bruce Ling; Jane Jijun Liu; Liangbiao Chen

2006-01-01

165

Approximate Differential Equations for Renormalization Group Functions in Models Free of  

E-print Network

Approximate Differential Equations for Renormalization Group Functions in Models Free of Vertex. In the case of linear Schwinger­Dyson equations, Broadhurst and Kreimer obtained differential equations, with a rational Mellin trans- form, the Schwinger­Dyson equation can be converted in a differential equation

Paris-Sud XI, Université de

166

Requirement for functional BK channels in maintaining oscillation in venomotor tone revealed by species differences in expression of the ?1 accessory subunits  

PubMed Central

We determined the possible role of large-conductance Ca2+-activated K+ (BK) channels in regulation of venous tone in small capacitance veins and blood pressure. In rat mesenteric venous smooth muscle cells (MV SMC), BK channel ?- and ?1-subunits were co-expressed, unitary BK currents were detected, and single channel currents were sensitive to voltage and [Ca2+]i. Rat MV SMCs displayed Ca2+ sparks and iberiotoxin (IBTX)-sensitive spontaneous transient outward currents (STOCs). Under resting conditions in vitro, rat MV exhibited nifedipine-sensitive spontaneous oscillatory constrictions. Blockade of BK channels by paxilline and Ca2+ sparks by ryanodine constricted rat MV. Nifedipine caused venodilation and blocked paxilline-, KCl (20 mM) and BayK 8644-induced contraction. Acute inhibition of BK channels with IBTX in vivo increased blood pressure and reduced venous capacitance, measured as an increase in mean circulatory filling pressure in conscious rats. BK channel ?-subunits and L-type Ca2+ channel ?1-C subunits are expressed in murine MV. However, these channels are not functional as murine MV lacked nifedipine-sensitive basal tone and rhythmic constrictions. Murine MV were also insensitive to paxilline, ryanodine, KCl and BayK8644, consistent with our previous studies showing that murine MV do not have BK ?1-subunits. These data show that not only there are species-dependent properties in ion channel control of venomotor tone, but also that BK channels are required for rhythmic oscillations in venous tone. PMID:21885988

Xu, Hui; Kandlikar, Sachin S; Westcott, Erika B; Fink, Gregory D; Galligan, James J

2011-01-01

167

On-site education of VEGF-recruited monocytes improves their performance as angiogenic and arteriogenic accessory cells  

PubMed Central

Adult neovascularization relies on the recruitment of monocytes to the target organ or tumor and functioning therein as a paracrine accessory. The exact origins of the recruited monocytes and the mechanisms underlying their plasticity remain unclear. Using a VEGF-based transgenic system in which genetically tagged monocytes are conditionally summoned to the liver as part of a VEGF-initiated angiogenic program, we show that these recruited cells are derived from the abundant pool of circulating Ly6Chi monocytes. Remarkably, however, upon arrival at the VEGF-induced organ, but not the naive organ, monocytes undergo multiple phenotypic and functional changes, endowing them with enhanced proangiogenic capabilities and, importantly, with a markedly increased capacity to remodel existing small vessels into larger conduits. Notably, monocytes do not differentiate into long-lived macrophages, but rather appear as transient accessory cells. Results from transfers of presorted subpopulations and a novel tandem transfer strategy ruled out selective recruitment of a dedicated preexisting subpopulation or onsite selection, thereby reinforcing active reprogramming as the underlying mechanism for improved performance. Collectively, this study uncovered a novel function of VEGF, namely, on-site education of recruited “standard” monocytes to become angiogenic and arteriogenic professional cells, a finding that may also lend itself for a better design of angiogenic therapies. PMID:24166715

Avraham-Davidi, Inbal; Yona, Simon; Grunewald, Myriam; Landsman, Limor; Cochain, Clement; Silvestre, Jean Sebastien; Mizrahi, Haim; Faroja, Mohammad; Strauss-Ayali, Dalit; Mack, Matthias

2013-01-01

168

One nose, one brain: contribution of the main and accessory olfactory system to chemosensation.  

PubMed

The accessory olfactory system is present in most tetrapods. It is involved in the perception of chemical stimuli, being implicated also in the detection of pheromones. However, it is sensitive also to some common odorant molecules, which have no clear implication in intraspecific chemical communication. The accessory olfactory system may complement the main olfactory system and may contribute different perceptual features to the construction of a unitary representation, which merges the different chemosensory qualities. Crosstalk between the main and accessory olfactory systems occurs at different levels of central processing, in brain areas where the inputs from the two systems converge. Interestingly, centrifugal projections from more caudal brain areas are deeply involved in modulating both main and accessory sensory processing. A high degree of interaction between the two systems may be conceived and partial overlapping appears to occur in many functions. Therefore, the central chemosensory projections merge inputs from different organs to obtain a complex chemosensory picture. PMID:23162438

Mucignat-Caretta, Carla; Redaelli, Marco; Caretta, Antonio

2012-01-01

169

The MIMIC Model as a Tool for Differential Bundle Functioning Detection  

ERIC Educational Resources Information Center

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)…

Finch, W. Holmes

2012-01-01

170

Establishing Effect Size Guidelines for Interpreting the Results of Differential Bundle Functioning Analyses Using SIBTEST  

ERIC Educational Resources Information Center

The purpose of this simulation study was to establish general effect size guidelines for interpreting the results of differential bundle functioning (DBF) analyses using simultaneous item bias test (SIBTEST). Three factors were manipulated: number of items in a bundle, test length, and magnitude of uniform differential item functioning (DIF)…

Walker, Cindy M.; Zhang, Bo; Banks, Kathleen; Cappaert, Kevin

2012-01-01

171

Correspondence between geometrical and differential definitions of the sine and cosine functions and connection with kinematics  

Microsoft Academic Search

In classical physics, the familiar sine and cosine functions appear in two forms: (1) geometrical, in the treatment of vectors such as forces and velocities, and (2) differential, as solutions of oscillation and wave equations. These two forms correspond to two different definitions of trigonometric functions, one geometrical using right triangles and unit circles, and the other employing differential equations.

Horia I. Petrache

2011-01-01

172

The Impact of Multidimensionality on the Detection of Differential Bundle Functioning Using Simultaneous Item Bias Test  

ERIC Educational Resources Information Center

Douglas, Roussos, and Stout introduced the concept of differential bundle functioning (DBF) for identifying the underlying causes of differential item functioning (DIF). In this study, reference group was simulated to have higher mean ability than the focal group on a nuisance dimension, resulting in DIF for each of the multidimensional items…

Furlow, Carolyn F.; Ross, Terris Raiford; Gagne, Phill

2009-01-01

173

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

ERIC Educational Resources Information Center

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…

Suh, Youngsuk; Bolt, Daniel M.

2011-01-01

174

Accessory liver lobes: anatomical description and clinical implications.  

PubMed

Accessory liver lobes are a rare condition and appear to be due to excessive development of the liver. The presence of an accessory hepatic lobe is often diagnosed incidentally and sometimes revealed if it develops torsion, especially in pedunculated forms. In most cases, the accessory lobe is located below the liver, i.e., infrahepatic. Riedel's lobe is the best-known example of an accessory lobe, corresponding to hypertrophy of segments V and VI. While accessories lobes can simulate tumors, there have also been reports of hepatocellular tumor(s) that developed in these accessory lobes. Based on a review of the literature, this update focuses on accessory hepatic lobes. PMID:25448768

Glenisson, M; Salloum, C; Lim, C; Lacaze, L; Malek, A; Enriquez, A; Compagnon, P; Laurent, A; Azoulay, D

2014-12-01

175

On the rank function of a differential poset  

E-print Network

We study r-differential posets, a class of combinatorial objects introduced in 1988 by the first author, which gathers together a number of remarkable combinatorial and algebraic properties, and generalizes important ...

Stanley, Richard P.

176

14 CFR 29.1163 - Powerplant accessories.  

Code of Federal Regulations, 2011 CFR

... (2) Use the provisions on the engine for mounting; and (3) Be sealed in such a way as to prevent contamination of the engine oil system and the accessory system. (b) Electrical equipment subject to arcing or sparking must be...

2011-01-01

177

14 CFR 27.1163 - Powerplant accessories.  

Code of Federal Regulations, 2013 CFR

... (2) Use the provisions on the engine for mounting; and (3) Be sealed in such a way as to prevent contamination of the engine oil system and the accessory system. (b) Unless other means are provided, torque limiting means...

2013-01-01

178

14 CFR 25.1163 - Powerplant accessories.  

Code of Federal Regulations, 2011 CFR

...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 sparking must be...

2011-01-01

179

14 CFR 29.1163 - Powerplant accessories.  

Code of Federal Regulations, 2014 CFR

... (2) Use the provisions on the engine for mounting; and (3) Be sealed in such a way as to prevent contamination of the engine oil system and the accessory system. (b) Electrical equipment subject to arcing or sparking must be...

2014-01-01

180

14 CFR 29.1163 - Powerplant accessories.  

Code of Federal Regulations, 2013 CFR

... (2) Use the provisions on the engine for mounting; and (3) Be sealed in such a way as to prevent contamination of the engine oil system and the accessory system. (b) Electrical equipment subject to arcing or sparking must be...

2013-01-01

181

14 CFR 29.1163 - Powerplant accessories.  

Code of Federal Regulations, 2012 CFR

... (2) Use the provisions on the engine for mounting; and (3) Be sealed in such a way as to prevent contamination of the engine oil system and the accessory system. (b) Electrical equipment subject to arcing or sparking must be...

2012-01-01

182

14 CFR 27.1163 - Powerplant accessories.  

Code of Federal Regulations, 2014 CFR

... (2) Use the provisions on the engine for mounting; and (3) Be sealed in such a way as to prevent contamination of the engine oil system and the accessory system. (b) Unless other means are provided, torque limiting means...

2014-01-01

183

14 CFR 25.1163 - Powerplant accessories.  

Code of Federal Regulations, 2010 CFR

...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 sparking must be...

2010-01-01

184

14 CFR 25.1163 - Powerplant accessories.  

Code of Federal Regulations, 2013 CFR

...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 sparking must be...

2013-01-01

185

14 CFR 27.1163 - Powerplant accessories.  

Code of Federal Regulations, 2011 CFR

... (2) Use the provisions on the engine for mounting; and (3) Be sealed in such a way as to prevent contamination of the engine oil system and the accessory system. (b) Unless other means are provided, torque limiting means...

2011-01-01

186

14 CFR 27.1163 - Powerplant accessories.  

Code of Federal Regulations, 2012 CFR

... (2) Use the provisions on the engine for mounting; and (3) Be sealed in such a way as to prevent contamination of the engine oil system and the accessory system. (b) Unless other means are provided, torque limiting means...

2012-01-01

187

14 CFR 25.1163 - Powerplant accessories.  

Code of Federal Regulations, 2014 CFR

...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 sparking must be...

2014-01-01

188

14 CFR 29.1163 - Powerplant accessories.  

Code of Federal Regulations, 2010 CFR

... (2) Use the provisions on the engine for mounting; and (3) Be sealed in such a way as to prevent contamination of the engine oil system and the accessory system. (b) Electrical equipment subject to arcing or sparking must be...

2010-01-01

189

14 CFR 27.1163 - Powerplant accessories.  

Code of Federal Regulations, 2010 CFR

... (2) Use the provisions on the engine for mounting; and (3) Be sealed in such a way as to prevent contamination of the engine oil system and the accessory system. (b) Unless other means are provided, torque limiting means...

2010-01-01

190

14 CFR 25.1163 - Powerplant accessories.  

Code of Federal Regulations, 2012 CFR

...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 sparking must be...

2012-01-01

191

Best Approximation in Spaces of Continuously Differentiable Functions.  

NASA Astrophysics Data System (ADS)

Let C('k){a,b} denote the space of continuously differentiable functions on the interval {a,b}, of the real line (//R), let (VBAR)(VBAR)q(VBAR)(VBAR) be any norm in C('k){a,b}. If M is a finite dimensional subspace of (C('k){a,b}, (VBAR)(VBAR)(,(.))(VBAR)(VBAR)(,k)), the local compactness of M guarantees the existence of at least one function g in M, such that (VBAR)(VBAR)f - g(VBAR)(VBAR)(,k) = d(f,M) = inf{(VBAR)(VBAR)f - h(VBAR)(VBAR)(,k): h (epsilon) M}, g is called a best approximation to f from M. The question of uniqueness of best approximation of functions in C('k){a,b}, from finite dimensional subspaces, has been investigated in several papers, with respect to several norms, for example,. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). In this thesis we introduce a new norm and derive results on the problem of best approximation with respect to this norm. It is defined as follows. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). With respect to (VBAR)(VBAR)(,(.))(VBAR)(VBAR)(,k), we will quickly notice that, finding the best approximation to f (epsilon) C('k){a,b} from (pi)(,n), the spaces of polynomials of degree (LESSTHEQ) n, reduces to finding the best approximation to f('(k)) from (pi)(,n -k); when n > k, with respect to (VBAR)(VBAR)(,(.))(VBAR)(VBAR)(,(INFIN)). And the subspaces (pi)(,n) are Chebyshev with respect to (VBAR)(VBAR)(,(.))(VBAR)(VBAR)(,k), for m (epsilon) N. Also, we will find conditions on the n-dimensional subspace M of C('k){a,b}, and on the point of f (epsilon) C('k){a,b}, that reduces the computation of the distance. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). to the distance of a point in (//R)('k+1) to a subspace of dimension (LESSTHEQ) n in (//R)('k+1), with respect to. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). We will also study subspaces where one of the following conditions is satisfied: h (epsilon) P(,m)(x) if and only if h('(k)) (epsilon) P(,m('(k)))(x('(k))). or h (epsilon) P(,m)(x) if and only if h('(k)) (epsilon) P(,m('(k)))(x('(k))). Then we will characterize finite dimensional Chebyshev subspaces of (C('k){a,b}, (VBAR)(VBAR)(,(.))(VBAR)(VBAR)(,k)), and we will find a property similar to the Haar property that we will call condition (H). We will also define a property derived from condition (H), that we will call condition (A). And we will study subspaces satisfying either condition H or condition (A).

Bounader, Elham

192

Giant epithelial cyst of the accessory spleen  

Microsoft Academic Search

Splenic cysts are uncommon, and cysts derived from the accessory spleen are rare. We report a case of a huge splenic cyst\\u000a derived from the accessory spleen in the omentum, concomitant with multiple epithelial cysts of the primary spleen. Both serum\\u000a and cystic fluid concentrations of carbohydrate antigen (CA)19-9 were markedly elevated. A huge monolocular cyst occupied\\u000a the entire abdomen.

Masaki Mori; Taro Ishii; Toru Iida; Fumihiko Tanaka; Hajime Takikawa; Kota Okinaga

2003-01-01

193

Middle East Respiratory Syndrome Coronavirus Accessory Protein 4a Is a Type I Interferon Antagonist  

PubMed Central

Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe acute respiratory infection with as yet unclear epidemiology. We previously showed that MERS-CoV counteracts parts of the innate immune response in human bronchiolar cells. Here we analyzed accessory proteins 3, 4a, 4b, and 5 for their abilities to inhibit the type I interferon response. Accessory protein 4a was found to block interferon induction at the level of melanoma differentiation-associated protein 5 (MDA5) activation presumably by direct interaction with double-stranded RNA. PMID:24027320

Niemeyer, Daniela; Zillinger, Thomas; Muth, Doreen; Zielecki, Florian; Horvath, Gabor; Suliman, Tasnim; Barchet, Winfried; Weber, Friedemann

2013-01-01

194

Activation of muscarinic acetylcholine receptors elevates intracellular Ca(2+) concentrations in accessory lobe neurons of the chick.  

PubMed

Accessory lobes are protrusions located at the lateral sides of the spinal cord of chicks and it has been proposed that they play a role as a sensory organ for equilibrium during walking. We have reported that functional neurons exist in the accessory lobe. As there is histological evidence that synaptic terminals of cholinergic nerves exist near the somata of accessory lobe neurons, we examined the effects of acetylcholine on changes in intracellular Ca(2+) concentrations ([Ca(2+)]i), as an index of cellular activities. Acetylcholine (0.1-100 µM) caused a transient rise in the [Ca(2+)]i. Acetylcholine-evoked [Ca(2+)]i rises were observed in the absence of extracellular Ca(2+), and they were abolished in the presence of cyclopiazonic acid, an inhibitor of Ca(2+)-ATPase of intracellular Ca(2+) stores or atropine, a muscarinic receptor antagonist. mRNAs coding M3 and M5 isoforms of the muscarinic receptors were detected in accessory lobes by the RT-PCR. These results indicate that chick accessory lobe neurons express functional muscarinic acetylcholine receptors, and that acetylcholine stimulates Ca(2+) mobilization from intracellular Ca(2+) stores, which elevates the [Ca(2+)]i in the somata of accessory lobe neurons, through activation of these receptors. Cholinergic synaptic transmission to the accessory lobe neurons may regulate some cellular functions through muscarinic receptors. PMID:25481714

Takahashi, Keita; Kitamura, Naoki; Suzuki, Yuki; Yamanaka, Yuko; Shinohara, Hikaru; Shibuya, Izumi

2015-04-01

195

Alternative delivery of male accessory gland products  

PubMed Central

To increase fertilization success, males transfer accessory gland products (Acps). Several species have evolved unconventional Acps transfer modes, meaning that Acps are transferred separately from the sperm. By surveying the sperm-free Acps transfer cases, we show that these animals have evolved a common strategy to deliver Acps: they all inject Acps directly through the partner’s body wall into the hemolymph. Our review of this mode of Acps transfer reveals another striking similarity: they all transfer sperm in packages or via the skin, which may leave little room for Acps transfer via the conventional route in seminal fluid. We synthesise the knowledge about the function, and the effects in the recipients, of the Acps found in the widely diverse taxa (including earthworms, sea slugs, terrestrial snails, scorpions and salamanders) that inject these substances. Despite the clearly independent evolution of the injection devices, these animals have evolved a common alternative strategy to get their partners to accept and/or use their sperm. Most importantly, the evolution of the injection devices for the delivery of Acps highlights how the latter are pivotal for male reproductive success and, hence, strongly influence sexual selection. PMID:24708537

2014-01-01

196

Alternative delivery of male accessory gland products.  

PubMed

To increase fertilization success, males transfer accessory gland products (Acps). Several species have evolved unconventional Acps transfer modes, meaning that Acps are transferred separately from the sperm. By surveying the sperm-free Acps transfer cases, we show that these animals have evolved a common strategy to deliver Acps: they all inject Acps directly through the partner's body wall into the hemolymph. Our review of this mode of Acps transfer reveals another striking similarity: they all transfer sperm in packages or via the skin, which may leave little room for Acps transfer via the conventional route in seminal fluid. We synthesise the knowledge about the function, and the effects in the recipients, of the Acps found in the widely diverse taxa (including earthworms, sea slugs, terrestrial snails, scorpions and salamanders) that inject these substances. Despite the clearly independent evolution of the injection devices, these animals have evolved a common alternative strategy to get their partners to accept and/or use their sperm. Most importantly, the evolution of the injection devices for the delivery of Acps highlights how the latter are pivotal for male reproductive success and, hence, strongly influence sexual selection. PMID:24708537

Zizzari, Z Valentina; Smolders, Irene; Koene, Joris M

2014-01-01

197

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

PubMed Central

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

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

2014-01-01

198

Signals that influence T follicular helper cell differentiation and function  

Microsoft Academic Search

Follicular helper T cells have recently emerged as a separate CD4+ T helper lineage specialised in provision of help to B cells. They develop independently from Th1, Th2 and Th17 cells and\\u000a are critical for humoral immunity, including the generation of long-lived and high affinity plasma cells and memory cells\\u000a crucial for long-term protection against infections. A stepwise differentiation programme

Michelle A. Linterman; Carola G. Vinuesa

2010-01-01

199

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

ERIC Educational Resources Information Center

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…

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

2013-01-01

200

An ordinary differential equation defined by a computable function whose maximal interval of  

E-print Network

An ordinary differential equation defined by a computable function whose maximal interval equations are fundamental in modeling physical processes, including nonlinear systems of ordinary differential equations (ODEs for short) x = f(t, x), where f : E Rn , E is an open subset of Rn+1 , x = x

Lisboa, Universidade Técnica de

201

Functional gene screening in embryonic stem cells implicates Wnt antagonism in neural differentiation  

Microsoft Academic Search

The multilineage differentiation capacity of mouse embryonic stem (ES) cells offers a potential testing platform for gene products that mediate mammalian lineage determination and cellular specialization. Identification of such differentiation regulators is crucial to harnessing ES cells for pharmaceutical discovery and cell therapy. Here we describe the use of episomal expression technology for functional evaluation of cDNA clones during ES-cell

Jerôme Aubert; Hannah Dunstan; Ian Chambers; Austin Smith

2002-01-01

202

A Comparison of Mantel-Haenszel Differential Item Functioning Parameters. LSAC Research Report Series.  

ERIC Educational Resources Information Center

Differential item functioning (DIF) analyses are conducted to investigate how items function in various subgroups. The Mantel-Haenszel (MH) DIF statistic is used at the Law School Admission Council and other testing companies. When item functioning can be well-described in terms of a one- or two-parameter logistic item response theory (IRT) model…

Schnipke, Deborah L.; Roussos, Louis A.; Pashley, Peter J.

203

Variation in Differential and Total Cross Sections Due to Different Radial Wave Functions  

ERIC Educational Resources Information Center

Three sets of analytical wave functions are used to calculate the Na (3s---3p) transition differential and total electron excitation cross sections by Born approximations. Results show expected large variations in values. (Author/CP)

Williamson, W., Jr.; Greene, T.

1976-01-01

204

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

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…

Thurman, Carol

2009-01-01

205

Differential Item Functioning: An Applied Comparison of the Item Characteristic Curve Method with the Logistic Discriminant Function Method.  

ERIC Educational Resources Information Center

This study compares logistic discriminant function analysis for differential item functioning (DIF) with a technique for the detection of DIF that is based on item response theory rather than the Mantel-Haenszel procedure. In this study, the areas between the two item characteristic curves, also called the item characteristic curve method is…

Holweger, Nancy; Weston, Timothy

206

Hypoalgesic effect of a passive accessory mobilisation technique in patients with lateral ankle pain  

Microsoft Academic Search

A randomised, double blind, repeated measures study was conducted to investigate the initial effects of an accessory mobilisation technique applied to the ankle joint in 13 patients with a unilateral sub-acute ankle supination injury. Ankle dorsiflexion range of motion, pressure pain threshold, visual analogue scale rating of pain during functional activity and ankle functional scores were assessed before and after

Hwee Koon Yeo; Anthony Wright

2011-01-01

207

Controlled Speed Accessory Drive demonstration program  

NASA Technical Reports Server (NTRS)

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.

Hoehn, F. W.

1981-01-01

208

Dual functions of TAF7L in adipocyte differentiation  

PubMed Central

The diverse transcriptional mechanisms governing cellular differentiation and development of mammalian tissue remains poorly understood. Here we report that TAF7L, a paralogue of TFIID subunit TAF7, is enriched in adipocytes and white fat tissue (WAT) in mouse. Depletion of TAF7L reduced adipocyte-specific gene expression, compromised adipocyte differentiation, and WAT development as well. Ectopic expression of TAF7L in myoblasts reprograms these muscle precursors into adipocytes upon induction. Genome-wide mRNA-seq expression profiling and ChIP-seq binding studies confirmed that TAF7L is required for activating adipocyte-specific genes via a dual mechanism wherein it interacts with PPAR? at enhancers and TBP/Pol II at core promoters. In vitro binding studies confirmed that TAF7L forms complexes with both TBP and PPAR?. These findings suggest that TAF7L plays an integral role in adipocyte gene expression by targeting enhancers as a cofactor for PPAR? and promoters as a component of the core transcriptional machinery. DOI: http://dx.doi.org/10.7554/eLife.00170.001 PMID:23326641

Zhou, Haiying; Kaplan, Tommy; Li, Yan; Grubisic, Ivan; Zhang, Zhengjian; Wang, P Jeremy; Eisen, Michael B; Tjian, Robert

2013-01-01

209

21 CFR 890.3025 - Prosthetic and orthotic accessory.  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 2012-04-01 false Prosthetic and orthotic accessory. 890.3025 Section...PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025 Prosthetic and orthotic accessory. (a)...

2012-04-01

210

21 CFR 890.3025 - Prosthetic and orthotic accessory.  

Code of Federal Regulations, 2014 CFR

... 2014-04-01 2014-04-01 false Prosthetic and orthotic accessory. 890.3025 Section...PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025 Prosthetic and orthotic accessory. (a)...

2014-04-01

211

21 CFR 872.6010 - Abrasive device and accessories.  

Code of Federal Regulations, 2012 CFR

...accessories. (a) Identification. An abrasive device and accessories is a device constructed of various abrasives, such as diamond chips, that are glued to shellac-based paper. The device is intended to remove excessive restorative materials,...

2012-04-01

212

21 CFR 884.6120 - Assisted reproduction accessories.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Assisted reproduction accessories. 884.6120 Section...OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6120 Assisted reproduction accessories. (a)...

2013-04-01

213

21 CFR 884.6120 - Assisted reproduction accessories.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Assisted reproduction accessories. 884.6120 Section...OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6120 Assisted reproduction accessories. (a)...

2012-04-01

214

21 CFR 884.6120 - Assisted reproduction accessories.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Assisted reproduction accessories. 884.6120 Section...OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6120 Assisted reproduction accessories. (a)...

2014-04-01

215

21 CFR 884.2960 - Obstetric ultrasonic transducer and accessories.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 false Obstetric ultrasonic transducer and accessories. 884...Devices § 884.2960 Obstetric ultrasonic transducer and accessories. (a) Identification. An obstetric ultrasonic transducer is a device used to...

2014-04-01

216

21 CFR 884.2960 - Obstetric ultrasonic transducer and accessories.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Obstetric ultrasonic transducer and accessories. 884...Devices § 884.2960 Obstetric ultrasonic transducer and accessories. (a) Identification. An obstetric ultrasonic transducer is a device used to...

2013-04-01

217

14 CFR 23.1192 - Engine accessory compartment diaphragm.  

Code of Federal Regulations, 2010 CFR

...accessory compartment diaphragm. 23.1192 Section 23.1192 Aeronautics and Space FEDERAL...accessory compartment diaphragm. For aircooled radial engines, the engine power section and all portions of the exhaust sytem...

2010-01-01

218

21 CFR 872.6640 - Dental operative unit and accessories.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Dental operative unit and accessories. 872...SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6640 Dental operative unit and accessories....

2014-04-01

219

21 CFR 872.6640 - Dental operative unit and accessories.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Dental operative unit and accessories. 872...SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6640 Dental operative unit and accessories....

2013-04-01

220

21 CFR 872.4920 - Dental electrosurgical unit and accessories.  

Code of Federal Regulations, 2014 CFR

... 2014-04-01 2014-04-01 false Dental electrosurgical unit and accessories. 872...SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4920 Dental electrosurgical unit and accessories....

2014-04-01

221

21 CFR 872.6640 - Dental operative unit and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Dental operative unit and accessories. 872...SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6640 Dental operative unit and accessories....

2010-04-01

222

21 CFR 872.4920 - Dental electrosurgical unit and accessories.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 2011-04-01 false Dental electrosurgical unit and accessories. 872...SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4920 Dental electrosurgical unit and accessories....

2011-04-01

223

21 CFR 872.4920 - Dental electrosurgical unit and accessories.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 2010-04-01 false Dental electrosurgical unit and accessories. 872...SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4920 Dental electrosurgical unit and accessories....

2010-04-01

224

21 CFR 872.6640 - Dental operative unit and accessories.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Dental operative unit and accessories. 872...SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6640 Dental operative unit and accessories....

2011-04-01

225

21 CFR 872.4920 - Dental electrosurgical unit and accessories.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 2013-04-01 false Dental electrosurgical unit and accessories. 872...SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4920 Dental electrosurgical unit and accessories....

2013-04-01

226

21 CFR 872.6640 - Dental operative unit and accessories.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Dental operative unit and accessories. 872...SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6640 Dental operative unit and accessories....

2012-04-01

227

21 CFR 872.4920 - Dental electrosurgical unit and accessories.  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 2012-04-01 false Dental electrosurgical unit and accessories. 872...SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4920 Dental electrosurgical unit and accessories....

2012-04-01

228

Reducing Exposure: Hands-free Kits and Other Accessories  

MedlinePLUS

... kits Hand-free kits may include audio or Bluetooth headsets and various types of body-worn accessories ... Other Accessories Interference with Pacemakers and Other Medical Devices Hearing Aids and Cell Phones Children and Cell ...

229

21 CFR 890.3025 - Prosthetic and orthotic accessory.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 2010-04-01 false Prosthetic and orthotic accessory. 890.3025 Section...PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025 Prosthetic and orthotic accessory. (a)...

2010-04-01

230

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

Code of Federal Regulations, 2010 CFR

...HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Singapore Free Trade Agreement Rules of Origin § 10.537 Accessories, spare parts, or tools. Accessories,...

2010-04-01

231

21 CFR 884.1720 - Gynecologic laparoscope and accessories.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Gynecologic laparoscope and accessories. 884.1720 ...Devices § 884.1720 Gynecologic laparoscope and accessories. (a) Identification. A gynecologic laparoscope is a device used to...

2012-04-01

232

21 CFR 884.1720 - Gynecologic laparoscope and accessories.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 false Gynecologic laparoscope and accessories. 884.1720 ...Devices § 884.1720 Gynecologic laparoscope and accessories. (a) Identification. A gynecologic laparoscope is a device used to...

2014-04-01

233

21 CFR 872.6010 - Abrasive device and accessories.  

Code of Federal Regulations, 2011 CFR

...accessories. (a) Identification. An abrasive device and accessories is a device constructed of various abrasives, such as diamond chips, that are glued to shellac-based paper. The device is intended to remove excessive restorative materials,...

2011-04-01

234

21 CFR 872.6010 - Abrasive device and accessories.  

Code of Federal Regulations, 2014 CFR

...accessories. (a) Identification. An abrasive device and accessories is a device constructed of various abrasives, such as diamond chips, that are glued to shellac-based paper. The device is intended to remove excessive restorative materials,...

2014-04-01

235

21 CFR 884.1175 - Endometrial suction curette and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Endometrial suction curette and accessories. 884.1175...Devices § 884.1175 Endometrial suction curette and accessories. (a) Identification. An endometrial suction curette is a device used to...

2010-04-01

236

19 CFR 10.456 - Accessories, spare parts or tools.  

Code of Federal Regulations, 2010 CFR

...HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Chile Free Trade Agreement Rules of Origin § 10.456 Accessories, spare parts or tools. Accessories, spare parts...

2010-04-01

237

19 CFR 10.456 - Accessories, spare parts or tools.  

Code of Federal Regulations, 2012 CFR

...HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Chile Free Trade Agreement Rules of Origin § 10.456 Accessories, spare parts or tools. Accessories, spare parts...

2012-04-01

238

19 CFR 10.456 - Accessories, spare parts or tools.  

Code of Federal Regulations, 2011 CFR

...HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Chile Free Trade Agreement Rules of Origin § 10.456 Accessories, spare parts or tools. Accessories, spare parts...

2011-04-01

239

19 CFR 10.456 - Accessories, spare parts or tools.  

Code of Federal Regulations, 2013 CFR

...HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Chile Free Trade Agreement Rules of Origin § 10.456 Accessories, spare parts or tools. Accessories, spare parts...

2013-04-01

240

19 CFR 10.456 - Accessories, spare parts or tools.  

Code of Federal Regulations, 2014 CFR

...HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Chile Free Trade Agreement Rules of Origin § 10.456 Accessories, spare parts or tools. Accessories, spare parts...

2014-04-01

241

Recurrence of symptomatic atrial fibrillation after successful catheter ablation of atrioventricular accessory pathways: a multivariate regression analysis.  

PubMed

The primary aim of this study is to investigate the factors related to the recurrence of atrial fibrillation (AF) after a successful ablation of atrioventricular accessory pathway. Thirty-seven patients with spontaneous AF (study group) were selected from 401 consecutive patients who underwent radiofrequency catheter ablation of atrioventricular accessory pathway. A multivariate regression analysis was used in order to evaluate the relationships between AF recurrence and patients' age, sex, atrial size, left ventricular function, location of accessory pathways, heart rate during atrioventricular re-entrant tachycardia and atrial vulnerability (induction of sustained AF) after a successful ablation. Atrioventricular accessory pathway was abolished in 36 of the study group patients and 351 of the control group patients. During the follow-up of 36 +/- 11 months, four patients (11.1%) from the study group experienced sustained AF. Multivariate regression analysis showed that, in patients with pre-ablation AF, older age and post-ablation atrial vulnerability were the only independent predictive factors for AF recurrence. We concluded that radiofrequency catheter ablation of atrioventricular accessory pathway greatly reduces the risk of AF in patients who had a history of symptomatic AF. Older patients and patients with inducible AF after accessory pathway ablation are at an increased risk of AF recurrence. These patients should be closely monitored after successful ablation of atrioventricular accessory pathways. PMID:16033607

Wang, L; Yang, H; Zhang, Y

2005-08-01

242

A study of continuous non-differentiable functions  

E-print Network

/(b ) for an integral values of p and . Then f(y) = A(y ) for all sufficientl large values of Proof. We consider a special sequence of values of y, namely y ~ p/(b ), (m = 1, 2, 3, ~ ~ ~ ). We write m-1 f(y)=)u=)u+u+)u=f +f +f n 0 n m n 1 2 3 n=0 n=lltf'I say. We... when ab & 1. Now let us consider the case when ab ~ 1 and ( ~ 1. We then assume that g(8) has a finite differential coefficient at some 8 g'(6 ) say. Then by Lemma 2. 3 we have as 8 ~ 80 F(y) ? -+ g'(8 ) as r ~ 1, BG 96 0 which is the same as F(y...

Nichols, Detta Kaye

1972-01-01

243

Mitochondrial function controls proliferation and early differentiation potential of embryonic stem cells  

PubMed Central

Pluripotent stem cells hold significant promise in regenerative medicine due to their unlimited capacity for self-renewal, and potential to differentiate into any cell type of the body. In the current study, we demonstrate that proper mitochondrial function is essential for proliferation of undifferentiated embryonic stem cells (ESCs). Attenuating mitochondrial function under self-renewing conditions makes these cells more glycolytic-dependent, and is associated with an increase in the mRNA reserves of Nanog, Oct4 and Sox2. In contrast, attenuating mitochondrial function during the first 7 days of differentiation results in normal repression of Oct4, Nanog and Sox2. However differentiation potential is compromised as revealed by abnormal transcription of multiple Hox genes. Furthermore, under differentiating conditions in which mitochondrial function is attenuated, tumorigenic cells continue to persist. Our results, therefore establish the importance of normal mitochondrial function in ESC proliferation, regulating differentiation, and preventing the emergence of tumorigenic cells during the process of differentiation. PMID:21425411

Mandal, Sudip; Lindgren, Anne G.; Srivastava, Anand S.; Clark, Amander T.; Banerjee, Utpal

2015-01-01

244

Differentiation  

NSDL National Science Digital Library

This is an activity about lunar magmatic differentiation, in which learners simulate the process of geological differentiation. The activity ends with an extension question that asks about the makeup of the highlands of the Moon. This activity is in Unit 2 of the Exploring the Moon teacher's guide and is designed for use especially, but not exclusively, with the Lunar Sample Disk program.

2012-08-03

245

Regeneration niche differentiates functional strategies of desert woody plant species  

PubMed Central

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 material, which is available to authorized users. PMID:20686787

Briggs, John M.

2010-01-01

246

Detection of accessory spleens with indium 111-labeled autologous platelets  

Microsoft Academic Search

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.

Harmon H. Davis; Ajit Varki; W. A. Heaton; B. A. Siegel

1980-01-01

247

Nonobstructing Accessory Mitral Valve Tissue and Ventricular Septal Defect  

Microsoft Academic Search

A 4-month-old boy with ventricular septal defect was found to have accessory mitral valve tissue attached to the anterior leaflet of the mitral valve. Operation was successfully performed to excise the accessory mitral tissue in the left ventricular outflow tract and close the ventricular septal defect. Most previously reported cases with accessory mitral valve tissue were associated with left ventricular

Hiroshi Izumoto; Kazuaki Ishihara; Masaaki Ogawa; Yutaka Fujii; Kotaro Oyama; Kohei Kawazoe

1996-01-01

248

49 CFR 390.17 - Additional equipment and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Additional equipment and accessories. 390.17 Section 390.17 Transportation...390.17 Additional equipment and accessories. Nothing in this subchapter shall...prohibit the use of additional equipment and accessories, not inconsistent with or...

2010-10-01

249

14 CFR 25.1192 - Engine accessory section diaphragm.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Engine accessory section diaphragm. 25.1192 Section...Fire Protection § 25.1192 Engine accessory section diaphragm. For reciprocating...system must be isolated from the engine accessory compartment by a diaphragm that...

2010-01-01

250

Differentiating High-Functioning Autism and Social Phobia  

ERIC Educational Resources Information Center

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,…

Tyson, Katherine E.; Cruess, Dean G.

2012-01-01

251

Integral estimates for differentiable functions on irregular domains  

SciTech Connect

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.

Besov, Oleg V [Steklov Mathematical Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2011-02-11

252

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

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4960 Operating tables and accessories and operating chairs and...

2010-04-01

253

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

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4950 Manual operating table and accessories and manual operating chair...

2010-04-01

254

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

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4950 Manual operating table and accessories and manual operating chair and...

2013-04-01

255

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

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4950 Manual operating table and accessories and manual operating chair and...

2014-04-01

256

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

Code of Federal Regulations, 2012 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4950 Manual operating table and accessories and manual operating chair and...

2012-04-01

257

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

Code of Federal Regulations, 2011 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4950 Manual operating table and accessories and manual operating chair and...

2011-04-01

258

Tracminer: traction-enhancing mining equipment accessory  

Microsoft Academic Search

Explains how the Tracminer project aimed to provide a robust, low cost device to be mounted as an accessory on the motorized wheels of traction machines, in order to increase grip on loose soils. The main goal was to provide a device increasing by 30-40 per cent the traction capacity of the given machine in soft or marshy soil working

Manuel Armada; Mario Maza; Jean-Guy Fontaine; Pablo Gonzalez de Santos; Vasilios Papantoniou

1997-01-01

259

Home Economics Careers in Apparel and Accessories.  

ERIC Educational Resources Information Center

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)…

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

260

Electronic Position Sensor for Power Operated Accessory  

DOEpatents

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.

Haag, Ronald H.; Chia, Michael I.

2005-05-31

261

Department of Pharmacology Shared Equipment Centrifugation & Accessories  

E-print Network

Department of Pharmacology Shared Equipment Centrifugation & Accessories 1 Sorvall RC-5B High Speed Centrifuge (2-233) 2 Sorvall RC-5C+ High Speed Centrifuges (2-233) 1 Beckman LE80 Ultracentrifuge (2-233) 1 Thermo-Sorvall Discovery M150 Ultracentrifuge (2-270) 1 Eppendorf High Speed 581OR Tabletop Centrifuge (2

262

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

ERIC Educational Resources Information Center

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,…

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

2012-01-01

263

DIFferential Testlet Functioning Definitions and Detection. Program Statistics Research Technical Report No. 91-9.  

ERIC Educational Resources Information Center

It is sometimes sensible to think of the fundamental unit of test construction as being larger than an individual item. This unit, dubbed the testlet, must pass muster in the same way that items do. One criterion of a good item is the absence of differential item functioning (DIF). The item must function in the same way as all important…

Wainer, Howard; And Others

264

A Conceptual Analysis of Differential Item Functioning in Terms of a Multidimensional Item Response Model.  

ERIC Educational Resources Information Center

A mathematical model is proposed to describe how group differences in distributions of abilities, which are distinct from the target ability, influence the probability of a correct item response. In the multidimensional approach, differential item functioning is considered a function of the educational histories of the examinees. (SLD)

Camilli, Gregory

1992-01-01

265

The method of local linear approximation in the theory of nonlinear functional-differential equations  

NASA Astrophysics Data System (ADS)

Conditions for the existence of solutions to the nonlinear functional-differential equation \\displaystyle \\frac{d^mx(t)}{dt^m}+(Fx)(t)=h(t), \\qquad t\\in\\ R, in the space of functions bounded on the axes are obtained by using local linear approximation to the operator F. Bibliography: 21 items.

Slyusarchuk, Vasilii E.

2010-10-01

266

A Generalized Formula for the Mantel-Haenszel Differential Item Functioning Parameter.  

ERIC Educational Resources Information Center

Derives a general formula for the population parameter being estimated by the Mantel-Haenszel differential item functioning (DIF) statistics. The formula is appropriate for uniform or nonuniform DIF and can be used regardless of the form of the item response function. Shows the relationship between this parameter and item difficulty. (SLD)

Roussos, Louis A.; Schnipke, Deborah L.; Pashley, Peter J.

1999-01-01

267

A Generalized Logistic Regression Procedure to Detect Differential Item Functioning among Multiple Groups  

ERIC Educational Resources Information Center

We present an extension of the logistic regression procedure to identify dichotomous differential item functioning (DIF) in the presence of more than two groups of respondents. Starting from the usual framework of a single focal group, we propose a general approach to estimate the item response functions in each group and to test for the presence…

Magis, David; Raiche, Gilles; Beland, Sebastien; Gerard, Paul

2011-01-01

268

An Investigation of Differential Item Functioning in the MELAB Listening Test  

ERIC Educational Resources Information Center

Differential item functioning (DIF) analysis is a way of determining whether test items function differently across subgroups of test takers after controlling for ability level. DIF results are used to evaluate tests' validity arguments. This study uses Rasch measurement to examine the Michigan English Language Assessment Battery listening test…

Aryadoust, Vahid; Goh, Christine C. M.; Kim, Lee Ong

2011-01-01

269

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

ERIC Educational Resources Information Center

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…

Planche, Pascale; Lemonnier, Eric

2012-01-01

270

Analysis of Sources of Latent Class Differential Item Functioning in International Assessments  

ERIC Educational Resources Information Center

In this study, we investigated differential item functioning (DIF) and its sources using a latent class (LC) modeling approach. Potential sources of LC DIF related to instruction and teacher-related variables were investigated using substantive and three statistical approaches: descriptive discriminant function, multinomial logistic regression,…

Oliveri, Maria Elena; Ercikan, Kadriye; Zumbo, Bruno

2013-01-01

271

Almost Sure Behaviour of $U$Statistics and Von Mises' Differentiable Statistical Functions  

Microsoft Academic Search

For $U$-Statistics and von Mises' differentiable statistical functions, when the regular functional is stationary of order zero, almost sure convergence to appropriate Wiener processes is studied. A second almost sure invariance principle, particularly useful in the context of the law of iterated logarithm and the probability of moderate deviations, is also established.

Pranab Kumar Sen

1974-01-01

272

The method of local linear approximation in the theory of nonlinear functional-differential equations  

SciTech Connect

Conditions for the existence of solutions to the nonlinear functional-differential equation (d{sup m}x(t))/dt{sup m} + (fx)(t)=h(t), t element of R in the space of functions bounded on the axes are obtained by using local linear approximation to the operator F. Bibliography: 21 items.

Slyusarchuk, Vasilii E [Ukranian State Academy of Water Economy (Ukraine)

2010-10-06

273

On the local cauchy problem for quasilinear hyperbolic functional differential systems  

Microsoft Academic Search

Generalized solutions of weakly coupled functional differential systems are investigated. Theorems on the existence, uniqueness and continuous dependence upon initial data are given. The local Cauchy problem is transformed into functional integral equations. The method of bicharacteristics and integral inequalities are used.

T. Czlapi?ski; Z. Kamont

1997-01-01

274

Existence of weak solutions of nonlinear functional differential equations with unbounded delay  

Microsoft Academic Search

A phase space for first order partial functional differential equations is constructed. Weak solutions of initial problems are investigated. A theorem on the existence of solutions of initial problems is proved. The method of quasilinearhation of a nonlinear problem and functional integral inequalities are used.

T. Czlapi?ski; Z. Kamont

2001-01-01

275

Norepinephrine transporter expression and function in noradrenergic cell differentiations  

Microsoft Academic Search

The classical view of norepinephrine transporter (NET) function is the re-uptake of released norepinephrine (NE) by mature sympathetic neurons and noradrenergic neurons of the locus ceruleus (LC; [1-3]). In this report we review previous data and present new results that show that NET is expressed in the young embryo in a wide range of neuronal and non-neuronal tissues and that

Maya Sieber-Blum; Zeguang Ren

2000-01-01

276

A non-coding transcript of nephronectin promotes osteoblast differentiation by modulating microRNA functions.  

PubMed

We investigated the roles of the non-coding transcripts and found that expression of a fragment containing the 3'-untranslated region (3'-UTR) of nephronectin in osteoblast progenitor cells MC3T3-E1 promoted cell differentiation dramatically. We hypothesized that the ectopically expressed 3'-UTR binds microRNAs and modulates their functions. ?-Catenin and GSK3? were up-regulated in the 3'-UTR-transfected cells, contributing to the increased cell differentiation, through reduction of EGFR and ERK phosphorylation. Activator of GSK3? promoted differentiation, while inhibitor of GSK3? blocked differentiation. Our results indicate that the non-coding transcripts are important in regulating cell activities and may have potential application for modulating endogenous microRNA functions. PMID:21784074

Lee, Shao-Chen; Fang, Ling; Wang, Chia-Hui; Kahai, Shireen; Deng, Zhaoqun; Yang, Burton B

2011-08-19

277

Differential geometry of the Fermat quartic and theta functions  

NASA Astrophysics Data System (ADS)

The universal curve over a finite cover of the moduli space of elliptic curves with level four structure is embedded in C as the Fermat quartic and is parametrized via the four Jacobi theta functions. Constructions from completely integrable systems have shown the importance of looking at the curvature of certain spaces and here we compute sectional curvatures. For our computations, we choose the ambient Fubini-Study metric of C. We also derive several theta identities which arise from the quartic's holomorphic two-form.

Hadnot, Jason

2012-02-01

278

Imaging diagnosis of accessory and cavitated uterine mass, a rare mullerian anomaly  

PubMed Central

Accessory and Cavitated Uterine Mass (ACUM) is a rare form of developmental Mullerian anomaly seen in young females, which presents as chronic recurrent pelvic pain and severe dysmenorrhea. It is an accessory cavity lying within an otherwise normal uterus. It is lined by functional endometrium and surrounded by myometrium-like smooth muscle cells; hence, it bears striking macroscopic and microscopic resemblance to the uterus. Hysterosalpingography (HSG), Ultrasonography (USG), and Magnetic Resonance Imaging (MRI) form the mainstay of diagnostic imaging. The entity is often under diagnosed; therefore, a high index of suspicion combined with HSG and MRI imaging can help in making an accurate diagnosis. PMID:25024530

Jain, Nishchint; Verma, Ritu

2014-01-01

279

A non-coding transcript of nephronectin promotes osteoblast differentiation by modulating microRNA functions  

Microsoft Academic Search

We investigated the roles of the non-coding transcripts and found that expression of a fragment containing the 3?-untranslated region (3?-UTR) of nephronectin in osteoblast progenitor cells MC3T3-E1 promoted cell differentiation dramatically. We hypothesized that the ectopically expressed 3?-UTR binds microRNAs and modulates their functions. ?-Catenin and GSK3? were up-regulated in the 3?-UTR-transfected cells, contributing to the increased cell differentiation, through

Shao-Chen Lee; Ling Fang; Chia-Hui Wang; Shireen Kahai; Zhaoqun Deng; Burton B. Yang

2011-01-01

280

Cyclic guanosine 3'-5'-monphosphate. High levels in the male accessory gland of Acheta domesticus and related crickets.  

PubMed

Guanosine 3',5'-monophosphate (cyclic GMP) was found in the accessory gland of reproductively mature male house crickets (Acheta domesticus (L.)) up to the exceptionally high level of 500 pmol/mg protein (10(-4) mol/kg wet weight). The identity of cricket cyclic GMP was confirmed by enzymatic and spectral analysis. A survey of 10 closely related species of Orthoptera indicated that high levels of cyclic GMP in the accessory gland occur in the subfamily Gryllinae, to which A. domesticus belongs. In these crickets, cyclic GMP in the accessory gland increases together with protein content during two weeks after the final molt. Levels are not augmented by dissection, and are independent of the presence of sperm in the seminal vesicles and of the production of spermatophores by the gland. The function of cyclic GMP in the accessory gland is not yet understood. PMID:172136

Fallon, A M; Wyatt, G R

1975-12-01

281

Biosynthesis of Active Bacillus subtilis Urease in the Absence of Known Urease Accessory Proteins  

Microsoft Academic Search

Received 1 June 2005\\/Accepted 27 July 2005 Bacillus subtilis contains urease structural genes but lacks the accessory genes typically required for GTP- dependent incorporation of nickel. Nevertheless, B. subtilis was shown to possess a functional urease, and the recombinant enzyme conferred low levels of nickel-dependent activity to Escherichia coli. Additional investi- gations of the system lead to the suggestion that

Jong Kyong Kim; Scott B. Mulrooney; Robert P. Hausinger

2005-01-01

282

Differences in development and cellular composition between neuronal cultures of rat accessory and main olfactory bulbs  

Microsoft Academic Search

We previously established a primary culture system of the accessory olfactory bulb (AOB) to investigate the functional roles of individual types of neuron in pheromonal signal processing. However, the detailed characteristics of cultured AOB neurons were not yet apparent. In the present study, we address the cytological aspects of cultured AOB neurons using immunocytochemical staining methods. Cultured AOB neurons were

Kazuyo Muramoto; Midori Kato-Negishi; Yoichiro Kuroda; Hideto Kaba; Masumi Ichikawa

2004-01-01

283

Recent advances in the numerical analysis of Volterra functional differential equations with variable delays  

NASA Astrophysics Data System (ADS)

The numerical analysis of Volterra functional integro-differential equations with vanishing delays has to overcome a number of challenges that are not encountered when solving [`]classical' delay differential equations with non-vanishing delays. In this paper I shall describe recent results in the analysis of optimal (global and local) superconvergence orders in collocation methods for such evolutionary problems. Following a brief survey of results for equations containing Volterra integral operators with non-vanishing delays, the discussion will focus on pantograph-type Volterra integro-differential equations with (linear and nonlinear) vanishing delays. The paper concludes with a section on open problems; these include the asymptotic stability of collocation solutions uh on uniform meshes for pantograph-type functional equations, and the analysis of collocation methods for pantograph-type functional equations with advanced arguments.

Brunner, Hermann

2009-06-01

284

DiffNet: automatic differential functional summarization of dE-MAP networks.  

PubMed

The study of genetic interaction networks that respond to changing conditions is an emerging research problem. Recently, Bandyopadhyay et al. (2010) proposed a technique to construct a differential network (dE-MAPnetwork) from two static gene interaction networks in order to map the interaction differences between them under environment or condition change (e.g., DNA-damaging agent). This differential network is then manually analyzed to conclude that DNA repair is differentially effected by the condition change. Unfortunately, manual construction of differential functional summary from a dE-MAP network that summarizes all pertinent functional responses is time-consuming, laborious and error-prone, impeding large-scale analysis on it. To this end, we propose DiffNet, a novel data-driven algorithm that leverages Gene Ontology (go) annotations to automatically summarize a dE-MAP network to obtain a high-level map of functional responses due to condition change. We tested DiffNet on the dynamic interaction networks following MMS treatment and demonstrated the superiority of our approach in generating differential functional summaries compared to state-of-the-art graph clustering methods. We studied the effects of parameters in DiffNet in controlling the quality of the summary. We also performed a case study that illustrates its utility. PMID:25009128

Seah, Boon-Siew; Bhowmick, Sourav S; Dewey, C Forbes

2014-10-01

285

Differentially Private Synthesization of Multi-Dimensional Data using Copula Functions  

PubMed Central

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 ? 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

Li, Haoran; Xiong, Li; Jiang, Xiaoqian

2014-01-01

286

Starches of varied digestibilities differentially modify intestinal function in rats.  

PubMed

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. PMID:8263598

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

1993-12-01

287

Differential Equation Approach for One- and Two- Dimensional Lattice Green's Function  

E-print Network

A first order differential equation of Green's Function, at the origin G(0), for the one- dimensional lattice is derived by simple recurrence relation. Green's Function at site (m)is then calculated in terms of G(0). A simple recurrence relation connecting the lattice Green's Function at the site (m,n)and the first derivative of the lattice Green's Function at the site (m+_1,n)is presented for the two- dimensional lattice, a differential equation of the second order in G(0,0) is obtained. By making use of the letter recurrence relation, lattice Green's Function at an arbitrary site is obtained in closed form. Finally, the phase shift and scattering cross section are evaluated analytically and numerically for one- and two impurities.

J. H. Asad

2009-04-03

288

On differential equation on four-point correlation function in the Conformal Toda Field Theory  

E-print Network

The properties of completely degenerate fields in the Conformal Toda Field Theory are studied. It is shown that a generic four-point correlation function that contains only one such field does not satisfy ordinary differential equation in contrast to the Liouville Field Theory. Some additional assumptions for other fields are required. Under these assumptions we write such a differential equation and solve it explicitly. We use the fusion properties of the operator algebra to derive a special set of three-point correlation function. The result agrees with the semiclassical calculations.

V. A. Fateev; A. V. Litvinov

2005-05-13

289

Regulation of CFTR expression and function during differentiation of intestinal epithelial cells.  

PubMed

CFTR, the protein defective in cystic fibrosis is regulated during differentiation of intestinal epithelial cells. The undifferentiated cells (Caco-2 and HT-29) show a lower level of CFTR mRNA, while a 10-fold increase is seen in differentiated cells. These differences correlate well with those of other intestinal-specific genes, including sucrase-isomaltase, villin and alpha 1-antitrypsin, indicating that the regulation is cell specific. In Caco-2 cells the increase in CFTR mRNA cannot be accounted for by increased transcription of the gene. These data indicate that CFTR mRNA stabilizing factor(s) might be present in differentiated cells. The higher levels of CFTR mRNA in differentiated cells are accompanied by decreased protein levels, indicating, as well, involvement of translational control in the regulation of CFTR in these cells. Finally, fully differentiated cells show lowered levels of cyclic AMP-activated C1- transport, the characteristic function of CFTR. Thus, CFTR function in differentiated cells is modulated by a complex interaction of regulatory elements. Caco-2 and HT-29 cells provide a suitable in vitro system in which to study the mechanism of regulation of CFTR. PMID:1378393

Sood, R; Bear, C; Auerbach, W; Reyes, E; Jensen, T; Kartner, N; Riordan, J R; Buchwald, M

1992-07-01

290

Regulation of CFTR expression and function during differentiation of intestinal epithelial cells.  

PubMed Central

CFTR, the protein defective in cystic fibrosis is regulated during differentiation of intestinal epithelial cells. The undifferentiated cells (Caco-2 and HT-29) show a lower level of CFTR mRNA, while a 10-fold increase is seen in differentiated cells. These differences correlate well with those of other intestinal-specific genes, including sucrase-isomaltase, villin and alpha 1-antitrypsin, indicating that the regulation is cell specific. In Caco-2 cells the increase in CFTR mRNA cannot be accounted for by increased transcription of the gene. These data indicate that CFTR mRNA stabilizing factor(s) might be present in differentiated cells. The higher levels of CFTR mRNA in differentiated cells are accompanied by decreased protein levels, indicating, as well, involvement of translational control in the regulation of CFTR in these cells. Finally, fully differentiated cells show lowered levels of cyclic AMP-activated C1- transport, the characteristic function of CFTR. Thus, CFTR function in differentiated cells is modulated by a complex interaction of regulatory elements. Caco-2 and HT-29 cells provide a suitable in vitro system in which to study the mechanism of regulation of CFTR. Images PMID:1378393

Sood, R; Bear, C; Auerbach, W; Reyes, E; Jensen, T; Kartner, N; Riordan, J R; Buchwald, M

1992-01-01

291

IRF6 is a mediator of Notch pro-differentiation and tumour suppressive function in keratinocytes.  

PubMed

While the pro-differentiation and tumour suppressive functions of Notch signalling in keratinocytes are well established, the underlying mechanisms remain poorly understood. We report here that interferon regulatory factor 6 (IRF6), an IRF family member with an essential role in epidermal development, is induced in differentiation through a Notch-dependent mechanism and is a primary Notch target in keratinocytes and keratinocyte-derived SCC cells. Increased IRF6 expression contributes to the impact of Notch activation on growth/differentiation-related genes, while it is not required for induction of 'canonical' Notch targets like p21(WAF1/Cip1), Hes1 and Hey1. Down-modulation of IRF6 counteracts differentiation of primary human keratinocytes in vitro and in vivo, promoting ras-induced tumour formation. The clinical relevance of these findings is illustrated by the strikingly opposite pattern of expression of Notch1 and IRF6 versus epidermal growth factor receptor in a cohort of clinical SCCs, as a function of their grade of differentiation. Thus, IRF6 is a primary Notch target in keratinocytes, which contributes to the role of this pathway in differentiation and tumour suppression. PMID:21909072

Restivo, Gaetana; Nguyen, Bach-Cuc; Dziunycz, Piotr; Ristorcelli, Elodie; Ryan, Russell J H; Özuysal, Özden Yalçin; Di Piazza, Matteo; Radtke, Freddy; Dixon, Michael J; Hofbauer, Günther F L; Lefort, Karine; Dotto, G Paolo

2011-11-16

292

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

SciTech Connect

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.

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

1987-05-01

293

Percutaneous laser balloon coagulation of accessory pathways  

NASA Astrophysics Data System (ADS)

Nonsurgical ablation techniques have been proposed to cease conduction through accessory pathways which electrically connect the atrium and ventricle. The intent of this research was to investigate further the potential use of laser energy, delivered via a balloon catheter in the canine coronary sinus to photocoagulate the myocardial fibers responsible for accessory pathway conduction. Based on histological evaluation of the lesions created in acute and chronic studies, the extent of coagulation necrosis is sufficient to ablate most pathways which lie adjacent to the coronary sinus. Results from surface temperature measurements using repetitive laser exposures suggest that optical and/or thermal changes occurring in the myocardium are of greater importance than those occurring in the adipose tissue. Since the laser balloon catheter is surrounded by various tissue types, a Monte Carlo model was developed to determine the distribution of light in the atrioventricular groove.

McMath, Linda P.; Schuger, Claudio D.; Crilley, Richard J.; Spears, J. Richard

1991-05-01

294

Antagonism of Innate Immunity by Paramyxovirus Accessory Proteins  

PubMed Central

Paramyxovirinae, a subfamily of Paramyxoviridae, are negative strand RNA viruses comprised of many important human and animal pathogens, which share a high degree of genetic and structural homology. The accessory proteins expressed from the P/V/C gene are major factors in the pathogenicity of the viruses, because of their ability to abrogate various facets of type I interferon (IFN) induction and signaling. Most of the paramyxoviruses exhibit a commonality in their ability to antagonize innate immunity by blocking IFN induction and the Jak/STAT pathway. However, the manner in which the accessory proteins inhibit the pathway differs among viruses. Similarly, there are variations in the capability of the viruses to counteract intracellular detectors (RNA helicases, mda-5 and RIG-I). Furthermore, a functional specificity in the antagonism of the IFN response has been reported, suggesting that specificity in the circumvention of innate immunity restricts viral host range. Available evidence indicates that paramyxoviruses employ specific strategies to antagonize the IFN response of their specific hosts, which is one of the major factors that determine viral pathogenicity and host range. PMID:21994561

Chambers, Raychel; Takimoto, Toru

2009-01-01

295

Transcriptional activation of melanocortin 2 receptor accessory protein by PPAR? in adipocytes  

SciTech Connect

Highlights: •MRAP enhanced HSL expression. •ACTH-mediated MRAP reduced glycerol release. •PPAR? induced MRAP expression. •PPAR? 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 ? (PPAR?) plays a role in the transcriptional regulation of metabolic pathways such as adipogenesis and ?-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 PPAR? 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 PPAR? is required for transcriptional activation of the MRAP gene during adipogenesis, which contributes to understanding of the molecular mechanism of lipolysis in adipocytes.

Kim, Nam Soo; Kim, Yoon-Jin [Department of Biology, Research Institute for Basic Science, Kyung Hee University, Seoul 130-701 (Korea, Republic of)] [Department of Biology, Research Institute for Basic Science, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Cho, Si Young [R and D Center, Amore Pacific Corporation, Yongin-si, Gyeonggi-do 446-729 (Korea, Republic of)] [R and D Center, Amore Pacific Corporation, Yongin-si, Gyeonggi-do 446-729 (Korea, Republic of); Lee, Tae Ryong, E-mail: trlee@amorepacific.com [R and D Center, Amore Pacific Corporation, Yongin-si, Gyeonggi-do 446-729 (Korea, Republic of); Kim, Sang Hoon, E-mail: shkim@khu.ac.kr [Department of Biology, Research Institute for Basic Science, Kyung Hee University, Seoul 130-701 (Korea, Republic of)

2013-09-27

296

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

ERIC Educational Resources Information Center

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…

Lee, HwaYoung; Beretvas, S. Natasha

2014-01-01

297

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

ERIC Educational Resources Information Center

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…

Gomez, Rapson

2012-01-01

298

Examination of Differential Item Functioning in Likert-Type Items Using Log-Linear Models.  

ERIC Educational Resources Information Center

The use of log-linear models for investigating differential item functioning (DIF) associated with examinee/respondent background characteristics was examined. The Likert-type items used in this study were drawn from a 36-item self-report measure--the Suicide Probability Scale. Specifically, log-linear models were used to investigate whether…

Dancer, L. Suzanne; And Others

299

A Synthesis of the Peer-Reviewed Differential Bundle Functioning Research  

ERIC Educational Resources Information Center

The purpose of this article was to present a synthesis of the peer-reviewed differential bundle functioning (DBF) research that has been conducted to date. A total of 16 studies were synthesized according to the following characteristics: tests used and learner groups, organizing principles used for developing bundles, DBF detection methods used,…

Banks, Kathleen

2013-01-01

300

DIFFERENTIAL ITEM FUNCTIONING AT POST ASSESSMENT BETWEEN TREATMENT AND CONTROL GROUPS FROM AN INCREASE IN KNOWLEDGE  

Technology Transfer Automated Retrieval System (TEKTRAN)

There has been some concern that participation in an intervention and exposure to a measurement instrument can distort subsequent responses to a questionnaire, thereby biasing results. Differential Item Functioning (DIF) analysis with Item Response Modeling (IRM) can test these effects by testing f...

301

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

ERIC Educational Resources Information Center

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,…

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

2009-01-01

302

Investigating Sources of Differential Item Functioning in International Large-Scale Assessments Using a Confirmatory Approach  

ERIC Educational Resources Information Center

International large-scale assessments of achievement often have a large degree of differential item functioning (DIF) between countries, which can threaten score equivalence and reduce the validity of inferences based on comparisons of group performances. It is important to understand potential sources of DIF to improve the validity of future…

Sandilands, Debra; Oliveri, Maria Elena; Zumbo, Bruno D.; Ercikan, Kadriye

2013-01-01

303

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

ERIC Educational Resources Information Center

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…

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

2009-01-01

304

A Confirmatory Approach to Differential Item Functioning on an ESL Reading Assessment  

ERIC Educational Resources Information Center

In this article, I describe a practical application of the Roussos and Stout (1996) multidimensional analysis framework for interpreting group performance differences on an ESL reading proficiency test. Although a variety of statistical methods have been developed for flagging test items that function differentially for equal ability examinees…

Abbott, Marilyn L.

2007-01-01

305

Differential Item Functioning Detection Using the Multiple Indicators, Multiple Causes Method with a Pure Short Anchor  

ERIC Educational Resources Information Center

The multiple indicators, multiple causes (MIMIC) method with a pure short anchor was proposed to detect differential item functioning (DIF). A simulation study showed that the MIMIC method with an anchor of 1, 2, 4, or 10 DIF-free items yielded a well-controlled Type I error rate even when such tests contained as many as 40% DIF items. In general,…

Shih, Ching-Lin; Wang, Wen-Chung

2009-01-01

306

A Comparison of Four Methods for Detecting Differential Item Functioning in Ordered Response Items  

ERIC Educational Resources Information Center

Item bias is a major threat to measurement validity. Methods for detecting differential item functioning (DIF) are now commonly used to identify potentially biased items. DIF detection methods for dichotomous items are well developed, but those for ordinal items are less well developed. In this article, the authors compare four methods for…

Kristjansson, Elizabeth; Aylesworth, Richard; Mcdowell, Ian; Zumbo, Bruno D.

2005-01-01

307

Testing for Nonuniform Differential Item Functioning with Multiple Indicator Multiple Cause Models  

ERIC Educational Resources Information Center

In extant literature, multiple indicator multiple cause (MIMIC) models have been presented for identifying items that display uniform differential item functioning (DIF) only, not nonuniform DIF. This article addresses, for apparently the first time, the use of MIMIC models for testing both uniform and nonuniform DIF with categorical indicators. A…

Woods, Carol M.; Grimm, Kevin J.

2011-01-01

308

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

ERIC Educational Resources Information Center

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…

Cid, Maria R.

2011-01-01

309

Differential Structure in non-Linear Image Embedding Functions Robert Pless  

E-print Network

pose estimates in rigid body motions [8], visualization of biomedical image data sets [3Differential Structure in non-Linear Image Embedding Functions Robert Pless Department of Computer Science, Washington University in St. Louis pless@cse.wustl.edu Abstract Many natural image sets

Pless, Robert

310

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

ERIC Educational Resources Information Center

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.…

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

2013-01-01

311

Differentiating plant cells switched to proliferation remodel the functional organization of nuclear domains  

Microsoft Academic Search

The immature pollen grain, the microspore, under stress conditions can switch its developmental program towards proliferation and embryogenesis. The comparison between the gametophytic and sporophytic pathways followed by the microspore permitted us to analyse the nuclear changes in plant differentiating cells when switched to proliferation. The nucleus is highly dynamic, the architecture of its well organised functional domains – condensed

P. S. Testillano; P. González-Melendi; M. J. Coronado; J. M. Seguí-Simarro; M. A. Moreno-Risueño; M. C. Risueño

2005-01-01

312

Gender Differences in Functioning for Older Adults in Rural Bangladesh. The Impact of Differential Reporting?  

Microsoft Academic Search

Background. The purpose of this study is to examine gender differences in functional ability among older adults in rural Bangladesh in terms of both self-reported activities of daily living and observed physical performance and to evaluate the extent to which differential reporting by gender contributes to disparities between the two measures. Methods. In 1996, the Matlab Health and Socio-Economic Survey

M. Omar Rahman; Ji-hong Liu

2000-01-01

313

Accommodations and Item-Level Analyses Using Mixture Differential Item Functioning Models  

ERIC Educational Resources Information Center

The purpose of this study was to use differential item functioning (DIF) and latent mixture model analyses to explore factors that explain performance differences on a large-scale mathematics assessment between examinees allowed to use a calculator or who were afforded item presentation accommodations versus those who did not receive the same…

Scarpati, Stanley E.; Wells, Craig S.; Lewis, Christine; Jirka, Stephen

2011-01-01

314

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

ERIC Educational Resources Information Center

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…

Magis, David; De Boeck, Paul

2012-01-01

315

Improvement of macular function by membrane differential filtration in diabetic retinopathy  

Microsoft Academic Search

BACKGROUND: Alterations of blood rheology are assumed to substantially contribute to the pathogenesis of diabetic retinopathy. Membrane differential filtration (MDF) is an extracorporeal treatment which is able to optimize rheological parameters by eliminating high molecular weight proteins and lipoproteins from the blood. The present study was designed to investigate the effects of repetitive MDF on visual function in diabetic retinopathy.

R. A. Widder; F. Soudavar; P. Walter; R. Brunner; H. Borberg

2001-01-01

316

Using Multiple-Variable Matching to Identify Cultural Sources of Differential Item Functioning  

ERIC Educational Resources Information Center

Identifying the sources of differential item functioning (DIF) in international assessments is very challenging, because such sources are often nebulous and intertwined. Even though researchers frequently focus on test translation and content area, few actually go beyond these factors to investigate other cultural sources of DIF. This article…

Wu, Amery D.; Ercikan, Kadriye

2006-01-01

317

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

ERIC Educational Resources Information Center

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…

Li, Xiaomin; Wang, Wen-Chung

2015-01-01

318

Lyapunov functions for quadratic differential equations with applications to adaptive control  

Microsoft Academic Search

Conditions are derived for the existence of quadratic Lyapunov functions for vector differential equations with quadratic terms. These conditions are used to establish a set of nonlinear equations for which the null solution is asymptotically stable in the whole. Many of the recent results in the stability of model reference adaptive systems are particular cases of these general conditions.

G. Luders; K. Narendra

1972-01-01

319

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

ERIC Educational Resources Information Center

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…

Magis, David; De Boeck, Paul

2011-01-01

320

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

ERIC Educational Resources Information Center

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…

Wang, Wei; Tay, Louis; Drasgow, Fritz

2013-01-01

321

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

ERIC Educational Resources Information Center

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…

Patarapichayatham, Chalie; Kamata, Akihito; Kanjanawasee, Sirichai

2012-01-01

322

The MIMIC Method with Scale Purification for Detecting Differential Item Functioning  

ERIC Educational Resources Information Center

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…

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

2009-01-01

323

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

ERIC Educational Resources Information Center

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…

Beinicke, Andrea; Pässler, Katja; Hell, Benedikt

2014-01-01

324

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

ERIC Educational Resources Information Center

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…

Keiffer, Elizabeth Ann

2011-01-01

325

Comparison of Differential Item Functioning Determination Techniques: HGLM, LR and IRT-LR  

ERIC Educational Resources Information Center

The aim of this research is to determine differential item functioning (DIF) by hierarchical linear modeling (HGLM) on test items and comparing these results by the DIF results determined by logistic regression (LR) and IRT-likelihood ratio (IRT-LR) techniques. Investigating the concordance between the techniques in determining the items with DIF,…

Acar, Tulin; Kelecioglu, Hulya

2010-01-01

326

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

ERIC Educational Resources Information Center

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.…

Finch, Holmes; French, Brian

2010-01-01

327

The Usefulness of Differential Item Functioning Methodology in Longitudinal Intervention Studies  

Technology Transfer Automated Retrieval System (TEKTRAN)

Perceived self-efficacy (SE) for engaging in physical activity (PA) is a key variable mediating PA change in interventions. The purpose of this study is to demonstrate the usefulness of item response modeling-based (IRM) differential item functioning (DIF) in the investigation of group differences ...

328

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

ERIC Educational Resources Information Center

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.…

Li, Zhushan

2014-01-01

329

Differential Item Functioning Analysis of Math Performance of Hispanic, Asian, and White NAEP Respondents.  

ERIC Educational Resources Information Center

The differential item functioning of mathematics performance of Hispanic, Asian, and White students on the National Assessment of Educational Progress (NAEP) was studied, using a modification of the Mantel-Haenszel Procedure. The sample for grades 3, 7, and 11, respectively, included: (1) 1,367, 1,570, and 1,580 Whites; (2) 265, 613, and 760…

Rock, Donald; Chan, Kaling

330

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

ERIC Educational Resources Information Center

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,…

Gao, Yong; Zhu, Weimo

2011-01-01

331

A Comparison of Adjacent Categories and Cumulative Differential Step Functioning Effect Estimators  

ERIC Educational Resources Information Center

The study of measurement invariance in polytomous items that targets individual score levels is known as differential step functioning (DSF). The analysis of DSF requires the creation of a set of dichotomizations of the item response variable. There are two primary approaches for creating the set of dichotomizations to conduct a DSF analysis: the…

Gattamorta, Karina A.; Penfield, Randall D.

2012-01-01

332

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

SciTech Connect

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.

Muehlhoff, Rainer [Berlin Mathematical School, TU Berlin, Mathematisches Institut, MA 2-2, Strasse des 17. Juni 136, 10623 Berlin (Germany)

2011-02-15

333

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

Microsoft Academic Search

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 TaskRegion interaction confirmed more dACC activation during color-word distractors and more rACC activation during emotion-word distractors. Activity in ACC subdivisions

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

2007-01-01

334

Barrier Function, Epidermal Differentiation, and Human ?-Defensin 2 Expression in Tinea Corporis  

Microsoft Academic Search

Tinea corporis is a superficial mycotic infection resulting in substantial epidermal changes. We determined skin barrier function, epidermal differentiation, and human-?-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

Jens-Michael Jensen; Stephan Pfeiffer; Tatsuya Akaki; Jens-Michael Schröder; Michael Kleine; Claudia Neumann; Ehrhardt Proksch; Jochen Brasch

2007-01-01

335

A Comparison of Empirical Differential Option Weighting Scoring Procedures as a Function of Inter-Item Correlation  

ERIC Educational Resources Information Center

The reliabilities yielded by several differential option weighting scoring procedures were compared among themselves as well as against conventional testing. It was found that increases in reliability due to differential option weighting were a function of inter-item correlations. Suggestions for the implementation of differential option weighting…

Bejar, Issac I.; Weiss, David J.

1977-01-01

336

Novel Functional Changes during Podocyte Differentiation: Increase of Oxidative Resistance and H-Ferritin Expression  

PubMed Central

Podocytes are highly specialized, arborized epithelial cells covering the outer surface of the glomerular tuft in the kidney. Terminally differentiated podocytes are unable to go through cell division and hereby they are lacking a key property for regeneration after a toxic injury. Podocytes are long-lived cells but, to date, little is known about the mechanisms that support their stress resistance. Our aim was to investigate whether the well-known morphological changes during podocyte differentiation are accompanied by changes in oxidative resistance in a manner that could support their long-term survival. We used a conditionally immortalized human podocyte cell line to study the morphological and functional changes during differentiation. We followed the differentiation process for 14 days by time-lapse microscopy. During this period nondifferentiated podocytes gradually transformed into large, nonproliferating, frequently multinucleated cells, with enlarged nuclei and opened chromatin structure. We observed that differentiated podocytes were highly resistant to oxidants such as H2O2 and heme when applied separately or in combination, whereas undifferentiated cells were prone to such challenges. Elevated oxidative resistance of differentiated podocytes was associated with increased activities of antioxidant enzymes and H-ferritin expression. Immunohistochemical analysis of normal human kidney specimens revealed that podocytes highly express H-ferritin in vivo as well. PMID:25097723

Balogh, Enik?; Arosio, Paolo; Király, Gábor; Nagy, Gábor; Tánczos, Bence; Balla, György; Balla, József; Bánfalvi, Gáspár

2014-01-01

337

30 CFR 75.1106-5 - Maintenance and tests of liquefied and nonliquefied compressed gas cylinders; accessories and...  

Code of Federal Regulations, 2010 CFR

...nonliquefied compressed gas cylinders; accessories and equipment; requirements...nonliquefied compressed gas cylinders; accessories and equipment; requirements...gages, and other cylinder accessories shall be maintained in a...

2010-07-01

338

Insights learned from pBTAi1, a 229-kb accessory plasmid from Bradyrhizobium sp. strain BTAi1 and prevalence of accessory plasmids in other Bradyrhizobium sp. strains  

Microsoft Academic Search

In silico, physiological and in planta analyses were used to characterize pBTAi1, a 229-kb accessory plasmid from Bradyrhizobium sp. strain BTAi1, and assess its potential ecological function under free-living and symbiotic growth conditions. Sequence analysis revealed the presence of an uptake hydrogenase system, a repABC family plasmid replication module and open reading frames encoding type IV secretion system, TraI and

Eddie J Cytryn; Siriluck Jitacksorn; Eric Giraud; Michael J Sadowsky

2008-01-01

339

Regulation of lymphoid development, differentiation, and function by the Notch pathway.  

PubMed

The Notch pathway is gaining increasing recognition as a key regulator of developmental choices, differentiation, and function throughout the hematolymphoid system. Notch controls the generation of hematopoietic stem cells during embryonic development and may affect their subsequent homeostasis. Commitment to the T cell lineage and subsequent stages of early thymopoiesis is critically regulated by Notch. Recent data indicate that Notch can also direct the differentiation and activity of peripheral T and B cells. Thus, the full spectrum of Notch effects is just beginning to be understood. In this review, we discuss this explosion of knowledge as well as current controversies and challenges in the field. PMID:15771590

Maillard, Ivan; Fang, Terry; Pear, Warren S

2005-01-01

340

Lhx1 controls terminal differentiation and circadian function of the suprachiasmatic nucleus.  

PubMed

Vertebrate circadian rhythms are organized by the hypothalamic suprachiasmatic nucleus (SCN). Despite its physiological importance, SCN development is poorly understood. Here, we show that Lim homeodomain transcription factor 1 (Lhx1) is essential for terminal differentiation and function of the SCN. Deletion of Lhx1 in the developing SCN results in loss of SCN-enriched neuropeptides involved in synchronization and coupling to downstream oscillators, among other aspects of circadian function. Intact, albeit damped, clock gene expression rhythms persist in Lhx1-deficient SCN; however, circadian activity rhythms are highly disorganized and susceptible to surprising changes in period, phase, and consolidation following neuropeptide infusion. Our results identify a factor required for SCN terminal differentiation. In addition, our in vivo study of combinatorial SCN neuropeptide disruption uncovered synergies among SCN-enriched neuropeptides in regulating normal circadian function. These animals provide a platform for studying the central oscillator's role in physiology and cognition. PMID:24767996

Bedont, Joseph L; LeGates, Tara A; Slat, Emily A; Byerly, Mardi S; Wang, Hong; Hu, Jianfei; Rupp, Alan C; Qian, Jiang; Wong, G William; Herzog, Erik D; Hattar, Samer; Blackshaw, Seth

2014-05-01

341

Lhx1 Controls Terminal Differentiation and Circadian Function of the Suprachiasmatic Nucleus  

PubMed Central

SUMMARY Vertebrate circadian rhythms are organized by the hypothalamic suprachiasmatic nucleus (SCN). Despite its physiological importance, SCN development is poorly understood. Here, we show that Lim homeodomain transcription factor 1 (Lhx1) is essential for terminal differentiation and function of the SCN. Deletion of Lhx1 in the developing SCN results in loss of SCN-enriched neuropeptides involved in synchronization and coupling to downstream oscillators, among other aspects of circadian function. Intact, albeit damped, clock gene expression rhythms persist in Lhx1-deficient SCN; however, circadian activity rhythms are highly disorganized and susceptible to surprising changes in period, phase, and consolidation following neuropeptide infusion. Our results identify a factor required for SCN terminal differentiation. In addition, our in vivo study of combinatorial SCN neuropeptide disruption uncovered synergies among SCN-enriched neuropeptides in regulating normal circadian function. These animals provide a platform for studying the central oscillator's role in physiology and cognition. PMID:24767996

Bedont, Joseph L.; LeGates, Tara A.; Slat, Emily A.; Byerly, Mardi S.; Wang, Hong; Hu, Jianfei; Rupp, Alan C.; Qian, Jiang; Wong, G. William; Herzog, Erik D.; Hattar, Samer; Blackshaw, Seth

2014-01-01

342

21 CFR 890.3025 - Prosthetic and orthotic accessory.  

Code of Federal Regulations, 2011 CFR

...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025 Prosthetic and orthotic accessory. (a)...

2011-04-01

343

21 CFR 890.3025 - Prosthetic and orthotic accessory.  

Code of Federal Regulations, 2013 CFR

...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025 Prosthetic and orthotic accessory. (a)...

2013-04-01

344

21 CFR 876.5130 - Urological catheter and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5130 Urological catheter and accessories. (a) Identification....

2013-04-01

345

21 CFR 876.4300 - Endoscopic electrosurgical unit and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4300 Endoscopic electrosurgical unit and accessories. (a)...

2010-04-01

346

21 CFR 876.1500 - Endoscope and accessories.  

Code of Federal Regulations, 2011 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Diagnostic Devices § 876.1500 Endoscope and accessories. (a) Identification. An...

2011-04-01

347

21 CFR 876.5130 - Urological catheter and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5130 Urological catheter and accessories. (a) Identification....

2010-04-01

348

21 CFR 876.4300 - Endoscopic electrosurgical unit and accessories.  

Code of Federal Regulations, 2012 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4300 Endoscopic electrosurgical unit and accessories. (a)...

2012-04-01

349

21 CFR 876.5980 - Gastrointestinal tube and accessories.  

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5980 Gastrointestinal tube and accessories. (a)...

2014-04-01

350

21 CFR 876.5820 - Hemodialysis system and accessories.  

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5820 Hemodialysis system and accessories. (a) Identification....

2014-04-01

351

21 CFR 876.5980 - Gastrointestinal tube and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5980 Gastrointestinal tube and accessories. (a)...

2010-04-01

352

21 CFR 876.5980 - Gastrointestinal tube and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5980 Gastrointestinal tube and accessories. (a)...

2013-04-01

353

21 CFR 876.5130 - Urological catheter and accessories.  

Code of Federal Regulations, 2012 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5130 Urological catheter and accessories. (a) Identification....

2012-04-01

354

21 CFR 876.5630 - Peritoneal dialysis system and accessories.  

Code of Federal Regulations, 2012 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5630 Peritoneal dialysis system and accessories. (a)...

2012-04-01

355

21 CFR 876.5630 - Peritoneal dialysis system and accessories.  

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5630 Peritoneal dialysis system and accessories. (a)...

2014-04-01

356

21 CFR 876.5130 - Urological catheter and accessories.  

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5130 Urological catheter and accessories. (a) Identification....

2014-04-01

357

21 CFR 876.1500 - Endoscope and accessories.  

Code of Federal Regulations, 2012 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Diagnostic Devices § 876.1500 Endoscope and accessories. (a) Identification. An...

2012-04-01

358

21 CFR 876.5980 - Gastrointestinal tube and accessories.  

Code of Federal Regulations, 2012 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5980 Gastrointestinal tube and accessories. (a)...

2012-04-01

359

21 CFR 876.5090 - Suprapubic urological catheter and accessories.  

Code of Federal Regulations, 2012 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5090 Suprapubic urological catheter and accessories. (a)...

2012-04-01

360

21 CFR 876.5090 - Suprapubic urological catheter and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5090 Suprapubic urological catheter and accessories. (a)...

2013-04-01

361

21 CFR 876.1500 - Endoscope and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Diagnostic Devices § 876.1500 Endoscope and accessories. (a) Identification. An...

2010-04-01

362

21 CFR 876.1500 - Endoscope and accessories.  

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Diagnostic Devices § 876.1500 Endoscope and accessories. (a) Identification. An...

2014-04-01

363

21 CFR 876.4300 - Endoscopic electrosurgical unit and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4300 Endoscopic electrosurgical unit and accessories. (a)...

2013-04-01

364

21 CFR 876.4300 - Endoscopic electrosurgical unit and accessories.  

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4300 Endoscopic electrosurgical unit and accessories. (a)...

2014-04-01

365

21 CFR 876.1500 - Endoscope and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Diagnostic Devices § 876.1500 Endoscope and accessories. (a) Identification. An...

2013-04-01

366

21 CFR 876.4300 - Endoscopic electrosurgical unit and accessories.  

Code of Federal Regulations, 2011 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4300 Endoscopic electrosurgical unit and accessories. (a)...

2011-04-01

367

21 CFR 876.5820 - Hemodialysis system and accessories.  

Code of Federal Regulations, 2012 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5820 Hemodialysis system and accessories. (a) Identification....

2012-04-01

368

21 CFR 876.5090 - Suprapubic urological catheter and accessories.  

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5090 Suprapubic urological catheter and accessories. (a)...

2014-04-01

369

21 CFR 876.5820 - Hemodialysis system and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5820 Hemodialysis system and accessories. (a) Identification....

2013-04-01

370

21 CFR 876.5980 - Gastrointestinal tube and accessories.  

Code of Federal Regulations, 2011 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5980 Gastrointestinal tube and accessories. (a)...

2011-04-01

371

21 CFR 876.5820 - Hemodialysis system and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5820 Hemodialysis system and accessories. (a) Identification....

2010-04-01

372

21 CFR 876.5090 - Suprapubic urological catheter and accessories.  

Code of Federal Regulations, 2011 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5090 Suprapubic urological catheter and accessories. (a)...

2011-04-01

373

21 CFR 876.5820 - Hemodialysis system and accessories.  

Code of Federal Regulations, 2011 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5820 Hemodialysis system and accessories. (a) Identification....

2011-04-01

374

21 CFR 876.5630 - Peritoneal dialysis system and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5630 Peritoneal dialysis system and accessories. (a)...

2010-04-01

375

21 CFR 876.5130 - Urological catheter and accessories.  

Code of Federal Regulations, 2011 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5130 Urological catheter and accessories. (a) Identification....

2011-04-01

376

Estimation of time- and state-dependent delays and other parameters in functional differential equations  

NASA Technical Reports Server (NTRS)

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.

Murphy, K. A.

1988-01-01

377

Investigating Linguistic Sources of Differential Item Functioning Using Expert Think-Aloud Protocols in Science Achievement Tests  

ERIC Educational Resources Information Center

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.…

Roth, Wolff-Michael; Oliveri, Maria Elena; Sandilands, Debra Dallie; Lyons-Thomas, Juliette; Ercikan, Kadriye

2013-01-01

378

A Comparison of Unidimensional and Three-Dimensional Differential Item Functioning Analysis Using Two-Dimensional Data  

ERIC Educational Resources Information Center

Oshima, Raju, and Flowers demonstrated the use of an item response theory-based technique for analyzing differential item function (DIF) and differential test function for dichotomously scored data that are intended to be multidimensional. Their study assumed that the number of intended-to-be measured dimensions was correctly identified. In…

Snow, Teresa K.; Oshima, T. C.

2009-01-01

379

Using Item Response Theory and Model-Data Fit to Conceptualize Differential Item and Person Functioning for Students with Disabilities  

ERIC Educational Resources Information Center

The major purpose of this study is to describe a conceptual framework for examining differential item functioning (DIF) and differential person functioning (DPF) as types of model-data misfit within the context of assessing students with disabilities. Specifically, DIF and DPF can be viewed through the lens of residual analyses. Residual analyses…

Engelhard, George, Jr.

2009-01-01

380

Diverse Broad-Host-Range Plasmids from Freshwater Carry Few Accessory Genes  

PubMed Central

Broad-host-range self-transferable plasmids are known to facilitate bacterial adaptation by spreading genes between phylogenetically distinct hosts. These plasmids typically have a conserved backbone region and a variable accessory region that encodes host-beneficial traits. We do not know, however, how well plasmids that do not encode accessory functions can survive in nature. The goal of this study was to characterize the backbone and accessory gene content of plasmids that were captured from freshwater sources without selecting for a particular phenotype or cultivating their host. To do this, triparental matings were used such that the only required phenotype was the plasmid's ability to mobilize a nonconjugative plasmid. Based on complete genome sequences of 10 plasmids, only 5 carried identifiable accessory gene regions, and none carried antibiotic resistance genes. The plasmids belong to four known incompatibility groups (IncN, IncP-1, IncU, and IncW) and two potentially new groups. Eight of the plasmids were shown to have a broad host range, being able to transfer into alpha-, beta-, and gammaproteobacteria. Because of the absence of antibiotic resistance genes, we resampled one of the sites and compared the proportion of captured plasmids that conferred antibiotic resistance to their hosts with the proportion of such plasmids captured from the effluent of a local wastewater treatment plant. Few of the captured plasmids from either site encoded antibiotic resistance. A high diversity of plasmids that encode no or unknown accessory functions is thus readily found in freshwater habitats. The question remains how the plasmids persist in these microbial communities. PMID:24096417

Sen, Diya; Yano, Hirokazu; Bauer, Matthew L.; Rogers, Linda M.; Van der Auwera, Geraldine A.

2013-01-01

381

A functional role of NMDA receptor in regulating the differentiation of oligodendrocyte precursor cells and remyelination.  

PubMed

Differentiation of oligodendrocyte precursor cells (OPCs) is the most important event for the myelination of central nervous system (CNS) axons during development and remyelination in demyelinating diseases, while the underlying molecular mechanisms remain largely unknown. Here we show that NMDA receptor (NMDAR) is a functional regulator of OPCs differentiation and remyelination. First, GluN1, GluN2A, and GluN2B subunits are expressed in oligodendrocyte lineage cells (OLs) in vitro and in vivo by immunostaining and Western blot analysis. Second, in a purified rat OPC culture system, NMDARs specially mediate OPCs differentiation by enhancing myelin proteins expression and the processes branching at the immature to mature oligodendrocyte transition analyzed by a serial of developmental stage-specific antigens. Moreover, pharmacological NMDAR antagonists or specific knockdown of GluN1 by RNA interference in OPCs prevents the differentiation induced by NMDA. NMDA can activate the mammalian target of rapamycin (mTOR) signal in OPCs and the pro-differentiation effect of NMDA is obstructed by the mTOR inhibitor rapamycin, suggesting NMDAR exerts its effect through mTOR-dependent mechanism. Furthermore, NMDA increases numbers of myelin segments in DRG-OPC cocultures. Finally, NMDAR specific antagonist MK801 delays remyelination in the cuprizone model examined by LFB-PAS, immunofluorescence and electron microscopy. This effect appears to result from inhibiting OPCs differentiation as more NG2(+) OPCs but less GST-?(+) mature oligodendrocytes are observed. Together, these results indicate that NMDAR plays a critical role in the regulation of OPCs differentiation in vitro and remyelination in cuprizone model which may provide potential target for the treatment of demyelination disease. PMID:23440860

Li, Cui; Xiao, Lin; Liu, Xiuyun; Yang, Wenjing; Shen, Weiran; Hu, Chun; Yang, Guang; He, Cheng

2013-05-01

382

Butyrate affects differentiation, maturation and function of human monocyte-derived dendritic cells and macrophages  

PubMed Central

We studied the in vitro effects of butyric acid on differentiation, maturation and function of dendritic cells (DC) and macrophages (M?) generated from human monocytes. A non-toxic dose of butyrate was shown to alter the phenotypic differentiation process of DC as assessed by a persistence of CD14, and a decreased CD54, CD86 and HLA class II expression. The more immature differentiation stage of treated cells was confirmed further by their increased phagocytic capability, their altered capacity to produce IL-10 and IL-12, and their weak allostimulatory abilities. Butyrate also altered DC terminal maturation, regardless of the maturation inducer, as demonstrated by a strong down-regulation of CD83, a decreased expression of CD40, CD86 and HLA class II. Similarly, butyrate altered M? differentiation, down-regulating the expression of the restricted membrane antigens and reducing the phagocytic capacity of treated cells. To investigate further the mechanism by which butyrate hampers the monocyte dual differentiation pathway, we studied the effects of 1,25(OH)2D3 alone or in combination with butyrate on the phenotypic features of DC. Unlike 1,25(OH)2D3, butyrate inhibited DC differentiation without redirecting it towards M?. Combined treatment gave rise to a new cell subset (CD14high, CD86 and HLA-DRlow) phenotypically distinct from monocytes. These results reveal an alternative mechanism of inhibition of DC and M? differentiation. Altogether, our data demonstrate a novel immune suppression property of butyrate that may modulate both inflammatory and immune responses and support further the interest for butyrate and its derivatives as new immunotherapeutic agents. PMID:12390312

Millard, A L; Mertes, P M; Ittelet, D; Villard, F; Jeannesson, P; Bernard, J

2002-01-01

383

GATA3 and the T-cell lineage: essential functions before and after T-helper-2-cell differentiation  

PubMed Central

Many advances in our understanding of the molecules that regulate the development, differentiation and function of T cells have been made over the past few years. One important regulator of T-cell differentiation is the transcription factor GATA3 (GATA-binding protein 3). Although the main function of GATA3 is to act as a master transcription factor for the differentiation of T helper 2 (TH2) cells, new research has helped to uncover crucial functions of GATA3 in T cells that go beyond TH2-cell differentiation, and that are important at earlier stages of haematopoietic- and lymphoid-cell development. This Review focuses on the functions of GATA3 from early thymocyte development to effector T-cell differentiation. In addition, we discuss the interactions between GATA3 and other transcription factors and signalling pathways, and highlight the functional significance of GATA3 protein structure. PMID:19151747

Ho, I-Cheng; Tai, Tzong-Shyuan; Pai, Sung-Yun

2010-01-01

384

Functional differentiation of the sugar beet root system as indicator of developmental phase change.  

PubMed

Developmental phase transitions in the plant root system have not been well characterized. In this study we compared the dynamics of sucrose accumulation with changes in gene expression analyzed with cDNA-amplified fragment length polymorphism (AFLP) in the developing tap root of sugar beet (Beta vulgaris, L.) during the first 9 weeks after emergence (WAE). Although differences between lines were evident as soon as 9 WAE, sucrose showed a marked increase in the rate of accumulation between 4 and 6 WAE and a remarkable shift in gene expression was observed between 5 and 6 WAE. These changes were evident in two unrelated genetic backgrounds and suggest that physiological and gene expression changes represent a functional differentiation of the tap root. These changes were considered as indicators of a developmental change in the sugar beet root system. To identify genes and metabolic pathways involved in this developmental shift, a root cDNA library was hybridized with probes enriched for 3- and 7-WAE transcripts and differentially expressed transcripts were analyzed by cDNA microarray. Several genes involved in the regulation of tissue development were found to be differentially regulated. Genes involved in protein metabolism, disease-related and secretory system were upregulated before the functional differentiation transition, while genes under hormonal control were upregulated after the functional differentiation transition. This developmental phase change of the root system is important to understand plant developmental regulation at the whole-plant level and will likely be useful as early selection parameter in breeding programs. PMID:19121102

Trebbi, Daniele; McGrath, J Mitchell

2009-01-01

385

An Efficient Spectral Method for Ordinary Differential Equations with Rational Function Coefficients  

NASA Technical Reports Server (NTRS)

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.

Coutsias, Evangelos A.; Torres, David; Hagstrom, Thomas

1994-01-01

386

Electrospun nanofibrillar surfaces promote neuronal differentiation and function from human embryonic stem cells.  

PubMed

In this study, the impact of randomly oriented electrospun polyamide nanofibrous architecture on neurogenic differentiation of human embryonic stem cells (hESCs) compared with the lack of nanofibrous features in vitro in a neural-inducing condition was examined. Flow cytometry analysis of hESC-derived neural ectoderm (NE) showed nanofibrous surfaces capable of supporting NE by expression of higher percentages of related markers NESTIN, SOX1, and PAX6 in addition to significantly greater total cell proliferation as shown by Ki67 in the neurogenic condition. After replating hESC-derived NE, the differentiated cells expressed higher neuronal markers (TUJ1 and MAP2) and motor neuron markers (HB9, ISL1, and ChAT) at both the protein and mRNA levels on nanofibers. The presence of developed spread neurites and plausible neurite connections were shown by scanning electron microscopy. Additionally, Na(+) and Ca(2+) currents in differentiated neurons on nanofibers were significantly greater than both control and generated action potentials. Moreover, less duration of inward currents, greater negative resting membrane potential, and enhanced expression and functionality of ionic channel genes were observed in neuronal cells on nanofibers. These results indicated that a nanofibrillar surface along with neurogenic growth factors provided a better environment for hESC neurogenic differentiation and function, which holds great promise in prospective tissue engineering applications. PMID:21740132

Shahbazi, Ebrahim; Kiani, Sahar; Gourabi, Hamid; Baharvand, Hossein

2011-12-01

387

76 FR 585 - In the Matter of Certain Handbags, Luggage, Accessories and Packaging Thereof; Notice of...  

Federal Register 2010, 2011, 2012, 2013, 2014

...In the Matter of Certain Handbags, Luggage, Accessories and Packaging Thereof...after importation of certain handbags. luggage, accessories and packaging thereof by...after importation of certain handbags, luggage, accessories and packaging thereof...

2011-01-05

388

49 CFR 178.255-7 - Protection of valves and accessories.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Protection of valves and accessories. 178.255-7 Section 178.255-7...178.255-7 Protection of valves and accessories. (a) All valves, fittings, accessories, safety devices, gauging...

2010-10-01

389

Migrate, Differentiate, Proliferate, or Die: Pleiotropic Functions of an Apical "Apoptotic Caspase"  

NSDL National Science Digital Library

Caspases, the cysteine proteases that cleave their substrates following an aspartate residue, primarily carry out two distinct functions: (i) activation of proinflammatory cytokines and (ii) execution of apoptosis. These two functions are considered to be unique to individual caspases; thus, some caspases act in apoptosis, whereas others have a role in inflammation. However, this dogma is now being challenged as nonapoptotic functions are ascribed to caspases that, until recently, were only known to function in cell death pathways. Recent work suggests that DRONC, the only initiator cell death caspase in Drosophila, may play a direct or indirect role in cell migration, sperm differentiation, and cell proliferation in addition to its function in cell death.

Sharad Kumar (Hanson Institute and Institute of Medical and Veterinary Science; REV)

2004-10-12

390

The DIF-Free-Then-DIF Strategy for the Assessment of Differential Item Functioning  

ERIC Educational Resources Information Center

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…

Wang, Wen-Chung; Shih, Ching-Lin; Sun, Guo-Wei

2012-01-01

391

BIFDE: software for the investigation of the Hopf bifurcation problem in functional differential equations  

Microsoft Academic Search

A Fortran package, BIFDE, which assists in the Hopf bifurcation analysis in systems of autonomous functional-differential equations, is described. Designed for flexibility, the program resolves generic and first-order nongeneric Hopf bifurcations in systems not necessarily of delay-difference (or even finite delay) form. The program's capabilities are illustrated by its application to a nonlinear model of `chugging' in liquid-propellant fuel rockets

Nihal Aboud; Archana Sathaye; Harlan Stech

1988-01-01

392

Differential Item Functioning of Pathological Gambling Criteria: An Examination of Gender, Race\\/Ethnicity, and Age  

Microsoft Academic Search

This study tested for the presence of differential item functioning (DIF) in DSM-IV Pathological Gambling Disorder (PGD) criteria\\u000a based on gender, race\\/ethnicity and age. Using a nationally representative sample of adults from the National Epidemiologic\\u000a Survey on Alcohol and Related Conditions (NESARC), indicating current gambling (n = 10,899), Multiple Indicator-Multiple Cause (MIMIC) models tested for DIF, controlling for income, education, and marital

Paul SaccoLuis; Luis R. Torres; Renee M. Cunningham-Williams; Carol Woods; G. Jay Unick

2011-01-01

393

Thymosin-?1 modulates dendritic cell differentiation and functional maturation from human peripheral blood CD14 + monocytes  

Microsoft Academic Search

Although thymosins have been demonstrated to have immunomodulatory effects, it is still not clear whether they could affect dendritic cells (DCs), the most professional antigen-presenting cells. The objective of this study was to determine the effect and potential mechanisms of thymosin-?1 (T?1) on DC differentiation and functional maturation. Human peripheral blood CD14+ monocytes were purified by using a magnetic separation

Qizhi Yao; Linh X. Doan; Rongxin Zhang; Uddalak Bharadwaj; Min Li; Changyi Chen

2007-01-01

394

Weak Convergence of $U$Statistics and Von Mises' Differentiable Statistical Functions  

Microsoft Academic Search

For partial cumulative sums of independent and identically distributed random variables (i.i.d.r.v.) with a finite (positive) variance, weak convergence to Brownian motion processes has been established by Donsker (1951, 1952). The result is extended here to differentiable statistical functions of von Mises (1947) and $U$-statistics of Hoeffding (1948). Along with the extension to generalized $U$-statistics, a few applications are briefly

R. G. Miller; Pranab Kumar Sen

1972-01-01

395

Differential item functioning (DIF) analyses of health-related quality of life instruments using logistic regression  

Microsoft Academic Search

BACKGROUND: Differential item functioning (DIF) methods can be used to determine whether different subgroups respond differently to particular items within a health-related quality of life (HRQoL) subscale, after allowing for overall subgroup differences in that scale. This article reviews issues that arise when testing for DIF in HRQoL instruments. We focus on logistic regression methods, which are often used because

Neil W Scott; Peter M Fayers; Neil K Aaronson; Andrew Bottomley; Alexander de Graeff; Mogens Groenvold; Chad Gundy; Michael Koller; Morten A Petersen; Mirjam AG Sprangers

2010-01-01

396

Topical hesperidin improves epidermal permeability barrier function and epidermal differentiation in normal murine skin.  

PubMed

Orange peel extract appears to exhibit beneficial effects on skin whitening, inflammation, UVB protection, as well as keratinocyte proliferation. In the present study, we determine whether topical hesperidin influences epidermal permeability barrier function and its underlying mechanisms. Hairless mice were treated topically with 2% hesperidin or 70% ethanol alone twice daily for 6 days. At the end of treatment, basal transepidermal water loss (TEWL) was measured 2 and 4 h post barrier disruption. Epidermal proliferation and differentiation were evaluated by immunohistochemical staining and Western blot analysis. Additionally, lamellar body density and secretion were assessed by electron microscopy. Although there were no significant differences in basal barrier function, in comparison with control animals, topical hesperidin significantly accelerated barrier recovery at both 2 and 4 h after acute barrier abrogation. Enhanced barrier function in hesperidin-treated skin correlated with stimulation of both epidermal proliferation and differentiation, as well as enhanced lamellar body secretion. These results indicate that topical hesperidin enhances epidermal permeability barrier homeostasis at least in part due to stimulation of epidermal proliferation, differentiation, as well as lamellar body secretion. PMID:22509829

Hou, Maihua; Man, Mona; Man, Wenyan; Zhu, Wenyuan; Hupe, Melanie; Park, Kyungho; Crumrine, Debra; Elias, Peter M; Man, Mao-Qiang

2012-05-01

397

From Monocytes to M1/M2 Macrophages: Phenotypical vs. Functional Differentiation  

PubMed Central

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

Italiani, Paola; Boraschi, Diana

2014-01-01

398

An in vitro model of innate lymphoid cell function and differentiation.  

PubMed

Innate lymphoid cells (ILC) are RAG-independent lymphocytes with important roles in innate immunity, and include group-1 (natural killer (NK) cell, ILC1), group-2 (ILC2), and group-3 (lymphoid tissue inducer (LTi), NCR(+) ILC3) subsets. Group-3 ILC express Ror?t, produce interleukin (IL)-22, and are critically important in the normal function of mucosal tissues. Here, we describe a novel model cell line for the study of ILC function and differentiation. The parental MNK cell line, derived from NKR-P1B(+) fetal thymocytes, shows a capacity to differentiate in ?c cytokines. One IL-7-responsive subline, designated MNK-3, expresses Ror?t and produces high levels of IL-22 in response to IL-23 and IL-1? stimulation. MNK-3 cells display surface markers and transcript expression characteristic of group-3 ILC, including IL-7R? (CD127), c-kit (CD117), CCR6, Thy1 (CD90), RANK, RANKL, and lymphotoxin (LT?1?2). Using an in vitro assay of LTi cell activity, MNK-3 cells induce ICAM-1 and VCAM-1 expression on stromal cells in a manner dependent upon LT?1?2 expression. A second IL-2-responsive subline, MNK-1, expresses several NK cell receptors, perforin and granzymes, and shows some cytotoxic activity. Thus, MNK-1 cells serve as a model of ILC1/NK development and differentiation, whereas MNK-3 cells provide an attractive in vitro system to study the function of ILC3/LTi cells. PMID:25138665

Allan, D Sj; Kirkham, C L; Aguilar, O A; Qu, L C; Chen, P; Fine, J H; Serra, P; Awong, G; Gommerman, J L; Zúñiga-Pflücker, J C; Carlyle, J R

2015-03-01

399

Accessory muscles around the foot and ankle presenting as chronic undiagnosed pain. An illustrative case report and review of the literature.  

PubMed

The differential diagnosis of ankle pain is extensive. Pathology may be classified as intra- or extra-articular. Additionally, ankle pain may be traumatic or non-traumatic. One of the unusual differential diagnoses for pain in the ankle is an accessory muscle. Magnetic resonance imaging is the radiological investigation of choice. However, this is invariably reported as normal unless one specifically looks for an accessory muscle. The purpose of this report is to highlight important features of these muscles and to draw attention to this uncommonly reported condition. PMID:24080333

Al-Himdani, S; Talbot, C; Kurdy, N; Pillai, A

2013-12-01

400

Reviewing prescription spending and accessory usage.  

PubMed

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. PMID:24642774

Oxenham, Julie

401

Accessory and anomalous atrioventricular valvar tissue causing outflow tract obstruction  

Microsoft Academic Search

Objectives. The purpose of this study was to determine the effect of accessory or anomalous atrioventricular valvar apparatus on relief of outflow tract obstruction.Background. Outflow tract obstruction due to accessory tissue or anomalous attachments of the atrioventricular valvar apparatus is an unusual but well-recognized problem. In addition to obstruction, anomalous attachments of the atrioventricular valvar apparatus may interfere with procedures

Doff B. McElhinney; V. Mohan Reddy; Norman H. Silverman; Frank L. Hanley

1998-01-01

402

Simon Effect with and without Awareness of the Accessory Stimulus  

ERIC Educational Resources Information Center

The authors investigated whether a Simon effect could be observed in an accessory-stimulus Simon task when participants were unaware of the task-irrelevant accessory cue. In Experiment 1A a central visual target was accompanied by a suprathreshold visual lateral cue. A regular Simon effect (i.e., faster cue-response corresponding reaction times…

Treccani, Barbara; Umilta, Carlo; Tagliabue, Mariaelena

2006-01-01

403

Differentially disrupted functional connectivity in posteromedial cortical subregions in Alzheimer's disease.  

PubMed

Neuroimaging studies have demonstrated that patients with Alzheimer's disease (AD) have remarkable focal grey matter loss and hypometabolism in the posteromedial cortex (PMC), which is composed of the precuneus and posterior cingulate cortex, suggesting an important association of the PMC with AD pathophysiology. Studies have also shown that the PMC is a structurally and functionally heterogeneous structure containing various subregions with distinct connectivity profiles. However, whether these PMC subregions show differentially disrupted connectivity patterns in AD remains largely unknown. Here, we addressed this issue by collecting resting-state functional MRI data from 32 AD patients and 38 healthy controls. We automatically identified the PMC subregions using a graph-based module detection algorithm and then mapped the whole-brain functional connectivity pattern of each subregion. The functional connectivity analysis was followed by a hierarchical clustering analysis to classify each subregion. Three distinct spatial connectivity patterns were observed across the PMC subregions: the anterior dorsal zone was functionally connected with the sensorimotor cortex; the posterior dorsal zone was functionally connected with the frontoparietal cortex; and the central and ventral zones were functionally connected with the default-mode regions. Group comparison analysis revealed that all three functional systems were significantly disrupted in the AD patients compared to the controls and these disruptions were positively correlated with the patients' cognitive performance. Collectively, we showed that the subregions of the PMC exhibit differentially disrupted neuronal circuitry in AD patients, which provides new insight into the functional neuroanatomy of the human PMC and the alterations that may be relevant to disease. PMID:24217277

Xia, Mingrui; Wang, Zhiqun; Dai, Zhengjia; Liang, Xia; Song, Haiqing; Shu, Ni; Li, Kuncheng; He, Yong

2014-01-01

404

21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.  

Code of Federal Regulations, 2014 CFR

...AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6190 Assisted... (a) Identification. Assisted reproduction microscopes and microscope accessories...which are classified under assisted reproduction accessories) are optical...

2014-04-01

405

21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.  

Code of Federal Regulations, 2010 CFR

...AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6190 Assisted... (a) Identification. Assisted reproduction microscopes and microscope accessories...which are classified under assisted reproduction accessories) are optical...

2010-04-01

406

21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.  

Code of Federal Regulations, 2013 CFR

...AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6190 Assisted... (a) Identification. Assisted reproduction microscopes and microscope accessories...which are classified under assisted reproduction accessories) are optical...

2013-04-01

407

21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.  

Code of Federal Regulations, 2011 CFR

...AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6190 Assisted... (a) Identification. Assisted reproduction microscopes and microscope accessories...which are classified under assisted reproduction accessories) are optical...

2011-04-01

408

21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.  

Code of Federal Regulations, 2012 CFR

...AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6190 Assisted... (a) Identification. Assisted reproduction microscopes and microscope accessories...which are classified under assisted reproduction accessories) are optical...

2012-04-01

409

Drosophila E-Cadherin Functions in Hematopoietic Progenitors to Maintain Multipotency and Block Differentiation  

PubMed Central

A fundamental question in stem cell biology concerns the regulatory strategies that control the choice between multipotency and differentiation. Drosophila blood progenitors or prohemocytes exhibit key stem cell characteristics, including multipotency, quiescence, and niche dependence. As a result, studies of Drosophila hematopoiesis have provided important insights into the molecular mechanisms that control these processes. Here, we show that E-cadherin is an important regulator of prohemocyte fate choice, maintaining prohemocyte multipotency and blocking differentiation. These functions are reminiscent of the role of E-cadherin in mammalian embryonic stem cells. We also show that mis-expression of E-cadherin in differentiating hemocytes disrupts the boundary between these cells and undifferentiated prohemocytes. Additionally, upregulation of E-cadherin in differentiating hemocytes increases the number of intermediate cell types expressing the prohemocyte marker, Patched. Furthermore, our studies indicate that the Drosophila GATA transcriptional co-factor, U-shaped, is required for E-cadherin expression. Consequently, E-cadherin is a downstream target of U-shaped in the maintenance of prohemocyte multipotency. In contrast, we showed that forced expression of the U-shaped GATA-binding partner, Serpent, repressed E-cadherin expression and promoted lamellocyte differentiation. Thus, U-shaped may maintain E-cadherin expression by blocking the inhibitory activity of Serpent. Collectively, these observations suggest that GATA:FOG complex formation regulates E-cadherin levels and, thereby, the choice between multipotency and differentiation. The work presented in this report further defines the molecular basis of prohemocyte cell fate choice, which will provide important insights into the mechanisms that govern stem cell biology. PMID:24040319

Gao, Hongjuan; Wu, Xiaorong; Fossett, Nancy

2013-01-01

410

Cellular Trafficking of Phospholamban and Formation of Functional Sarcoplasmic Reticulum During Myocyte DIfferentiation  

SciTech Connect

The sarco/endoplasmic reticulum Ca-ATPase (SERCA) family members are transmembrane proteins that play an essential role in regulating intracellular calcium levels. Phospholamban (PLB), a 52 amino acid phosphoprotein, regulates SERCA activity in adult heart and skeletal muscle. Using the C2C12 myocyte cell line, we find endogenous PLB constitutively expressed in both myoblasts and myotubes, whereas SERCA expression coincides with activation of the differentiation program. PLB has a punctuate distribution in myoblasts changing to a reticular distribution in myotubes where it colocalizes with SERCAs. To examine the distribution and dynamics of PLB and SERCA, we expressed fluorescent fusion proteins (GFP, CFP, and YFP) of PLB and SERCA in myoblasts. Coexpressed PLB and SERCA localize to distinct cellular compartments in myoblasts but begin to colocalize as cells differentiate. Fluorescence Recovery After Photobleaching (FRAP) studies show different recovery patterns for each protein in myoblasts confirming their localization to distinct compartments. To extend these studies, we created stable cell lines expressing O6-alkylguanine-DNA alkyltransferase (AGT) fusions with PLB or SERCA to track their localization as myocytes differentiate. These experiments demonstrate that PLB localizes to punctate vesicles in myoblasts and adopts a reticular distribution that coincides with SERCA distribution after differentiation. Colocalization experiments indicate that a subset of PLB in myoblasts colocalizes with endosomes, Golgi, and the plasma membrane however PLB also localizes to other, as yet unidentified vesicles. Our results indicate that differentiation plays a critical role in regulating PLB distribution to ensure its colocalization within the same cellular compartment as SERCA in differentiated cells. The presence and altered distribution of PLB in undifferentiated myoblasts raises the possibility that this protein has additional functions distinct from SERCA regulation.

Stenoien, David L.; Knyushko, Tatyana V.; Londono, Monica P.; Opresko, Lee; Mayer, M. Uljana; Brady, Scott T.; Squier, Thomas C.; Bigelow, Diana J.

2007-06-01

411

?-Catenin Functions Pleiotropically in Differentiation and Tumorigenesis in Mouse Embryo-Derived Stem Cells  

PubMed Central

The canonical Wnt/?-catenin signaling pathway plays a crucial role in the maintenance of the balance between proliferation and differentiation throughout embryogenesis and tissue homeostasis. ?-Catenin, encoded by the Ctnnb1 gene, mediates an intracellular signaling cascade activated by Wnt. It also plays an important role in the maintenance of various types of stem cells including adult stem cells and cancer stem cells. However, it is unclear if ?-catenin is required for the derivation of mouse embryo-derived stem cells. Here, we established ?-catenin-deficient (?-cat?/?) mouse embryo-derived stem cells and showed that ?-catenin is not essential for acquiring self-renewal potential in the derivation of mouse embryonic stem cells (ESCs). However, teratomas formed from embryo-derived ?-cat?/? ESCs were immature germ cell tumors without multilineage differentiated cell types. Re-expression of functional ?-catenin eliminated their neoplastic, transformed phenotype and restored pluripotency, thereby rescuing the mutant ESCs. Our findings demonstrate that ?-catenin has pleiotropic effects in ESCs; it is required for the differentiation of ESCs and prevents them from acquiring tumorigenic character. These results highlight ?-catenin as the gatekeeper in differentiation and tumorigenesis in ESCs. PMID:23691006

Okumura, Noriko; Akutsu, Hidenori; Sugawara, Tohru; Miura, Takumi; Takezawa, Youki; Hosoda, Akihiro; Yoshida, Keiichi; Ichida, Justin K.; Yamada, Mitsutoshi; Hamatani, Toshio; Kuji, Naoaki; Miyado, Kenji; Yoshimura, Yasunori; Umezawa, Akihiro

2013-01-01

412

Olig1 function is required for oligodendrocyte differentiation in the mouse brain.  

PubMed

Oligodendrocyte differentiation and myelination are tightly regulated processes orchestrated by a complex transcriptional network. Two bHLH transcription factors in this network, Olig1 and Olig2, are expressed exclusively by oligodendrocytes after late embryonic development. Although the role of Olig2 in the lineage is well established, the role of Olig1 is still unclear. The current studies analyzed the function of Olig1 in oligodendrocyte differentiation and developmental myelination in brain. Both oligodendrocyte progenitor cell commitment and oligodendrocyte differentiation were impaired in the corpus callosum of Olig1-null mice, resulting in hypomyelination throughout adulthood in the brain. As seen in previous studies with this mouse line, although there was an early myelination deficit in the spinal cord, essentially full recovery with normal spinal cord myelination was seen. Intriguingly, this regional difference may be partially attributed to compensatory upregulation of Olig2 protein expression in the spinal cord after Olig1 deletion, which is not seen in brain. The current study demonstrates a unique role for Olig1 in promoting oligodendrocyte progenitor cell commitment, differentiation, and subsequent myelination primarily in brain, but not spinal cord. PMID:25762682

Dai, Jinxiang; Bercury, Kathryn K; Ahrendsen, Jared T; Macklin, Wendy B

2015-03-11

413

Regulation of adult neurogenesis by behavior and age in the accessory olfactory bulb.  

PubMed

The vomeronasal system (VNS) participates in the detection and processing of pheromonal information related to social and sexual behaviors. Within the VNS, two different populations of sensory neurons, with a distinct pattern of distribution, line the epithelium of the vomeronasal organ (VNO) and give rise to segregated sensory projections to the accessory olfactory bulb (AOB). Apical sensory neurons in the VNO project to the anterior AOB (aAOB), while basal neurons project to the posterior AOB (pAOB). In the AOB, the largest population of neurons are inhibitory, the granule and periglomerular cells (GCs and PGs) and remarkably, these neurons are continuously born and functionally integrated in the adult brain, underscoring their role on olfactory function. Here we show that behaviors mediated by the VNS differentially regulate adult neurogenesis across the anterior-posterior axis of the AOB. We used immunohistochemical labeling of newly born cells under different behavioral conditions in mice. Using a resident-intruder aggression paradigm, we found that subordinate mice exhibited increased neurogenesis in the aAOB. In addition, in sexually naive adult females exposed to soiled bedding odorized by adult males, the number of newly born cells was significantly increased in the pAOB; however, neurogenesis was not affected in females exposed to female odors. In addition, we found that at two months of age adult neurogenesis was sexually dimorphic, with male mice exhibiting higher levels of newly born cells than females. Interestingly, adult neurogenesis was greatly reduced with age and this decrease correlated with a decrease in progenitor cells proliferation but not with an increase in cell death in the AOB. These results indicate that the physiological regulation of adult neurogenesis in the AOB by behaviors is both sex and age dependent and suggests an important role of newly born neurons in sex dependent behaviors mediated by the VNS. PMID:21600286

Nunez-Parra, Alexia; Pugh, Victoria; Araneda, Ricardo C

2011-08-01

414

The beta function of gauge theories at two loops in differential renormalization  

NASA Astrophysics Data System (ADS)

This PhD thesis is devoted to show that differential renormalization is a simple and useful renormalization method that we can use when dealing with gauge theories. In this work, it is shown how the one-loop results of Constraint Differential Renormalization can be fruitfully applied when renormalizing two-loop amplitudes. As an example of this procedure, the two-loop beta functions of various relevant gauge theories are obtained (QED, SuperQED, Yang-Mills and N=1 SuperYM) without making use of the Ward identities, which are mandatory in the standard differential renormalization procedure. Also, we study how to deal with expressions that have IR and UV divergences, showing that both are renormalized with independent scales. This result allow us to give new insight on the origin of the higher order corrections to the beta function of the N=1 SuperYM theory, as in this case we have both divergences due to the form of the gauge propagator. This is an advantage over usual dimensional regularization methods, where both divergences become mixed.

Seijas, Cesar

2007-06-01

415

HIF-2? downregulation in the absence of functional VHL is not sufficient for renal cell differentiation  

PubMed Central

Background Mutational inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene has been linked to hereditary as well as sporadic clear cell renal carcinomas. The product of the VHL gene, pVHL, acts to target hypoxia-inducible factor alpha (HIF-?) subunits for ubiquitination and subsequent degradation. Using an RNA interference approach to lower levels of HIF-2? in two different renal cell lines that lack functional pVHL, we have tested the contribution of HIF-2? toward cellular pVHL activities. Results Knockdown of HIF-2? resulted in cell cycle arrest of renal cells that were grown on collagen I, indicating that this pVHL function is dependent on HIF-2? regulation. However, cellular morphological changes and downregulation of integrins ?5 and ?1, which were seen upon pVHL replacement, were not faithfully phenocopied by HIF-2? reduction. Moreover, fibronectin deposition and expression of renal cell differentiation markers were observed in cells containing replaced pVHL, but not in HIF-2? knockdown cells, indicating that these pVHL functions may occur independently of HIF-2? downregulation. Conclusion These results indicate that HIF-2? regulation is not sufficient for pVHL-induced renal cell differentiation. We hypothesize that in addition to HIF-2? dysregulation, abrogation of additional pVHL functions is required for the initiation of renal carcinogenesis. PMID:17598890

Hughes, Michael D; Kapllani, Erilda; Alexander, Ashlynn E; Burk, Robert D; Schoenfeld, Alan R

2007-01-01

416

Parameter optimization by using differential elimination: a general approach for introducing constraints into objective functions  

PubMed Central

Background The investigation of network dynamics is a major issue in systems and synthetic biology. One of the essential steps in a dynamics investigation is the parameter estimation in the model that expresses biological phenomena. Indeed, various techniques for parameter optimization have been devised and implemented in both free and commercial software. While the computational time for parameter estimation has been greatly reduced, due to improvements in calculation algorithms and the advent of high performance computers, the accuracy of parameter estimation has not been addressed. Results We propose a new approach for parameter optimization by using differential elimination, to estimate kinetic parameter values with a high degree of accuracy. First, we utilize differential elimination, which is an algebraic approach for rewriting a system of differential equations into another equivalent system, to derive the constraints between kinetic parameters from differential equations. Second, we estimate the kinetic parameters introducing these constraints into an objective function, in addition to the error function of the square difference between the measured and estimated data, in the standard parameter optimization method. To evaluate the ability of our method, we performed a simulation study by using the objective function with and without the newly developed constraints: the parameters in two models of linear and non-linear equations, under the assumption that only one molecule in each model can be measured, were estimated by using a genetic algorithm (GA) and particle swarm optimization (PSO). As a result, the introduction of new constraints was dramatically effective: the GA and PSO with new constraints could successfully estimate the kinetic parameters in the simulated models, with a high degree of accuracy, while the conventional GA and PSO methods without them frequently failed. Conclusions The introduction of new constraints in an objective function by using differential elimination resulted in the drastic improvement of the estimation accuracy in parameter optimization methods. The performance of our approach was illustrated by simulations of the parameter optimization for two models of linear and non-linear equations, which included unmeasured molecules, by two types of optimization techniques. As a result, our method is a promising development in parameter optimization. PMID:20840736

2010-01-01

417

Evolution of the continental crust as recorded in accessory minerals  

NASA Astrophysics Data System (ADS)

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-Hf isotope systematics of zircon in that they define the timing of the crystallization and magmatic protolith formation (model age), respectively. The lack of monazites having >3.6 Ga crystallization ages as well as >4.0 Ga Nd model ages in the Mt. Narryer and Jack Hills metasedimentary rocks suggests that the source rocks of the Hadean detrital zircons are not low-Ca granitoids and therefore contained few monazites. Given that low-Ca granitoid magmas generated mainly by melting of pre-existing mid-lower crust, this finding may indicate minor intra-crustal melting and, by extension, crustal stabilization until ca. 3.6 Ga. This is consistent with the picture portrayed by the detrital zircons from modern rivers. Presumably, the hotter and rheologically weaker lithospheric mantle fostered many small plates and island arcs early in Earth's history, and the young arc crust was efficiently returned to the mantle via subduction. Accordingly, net growth of continental crust was essentially minor in early Earth's history despite high rates of crust generation.

Iizuka, Tsuyoshi

2013-04-01

418

A semi-discrete scheme for solving nonlinear hyperbolic-type partial integro-differential equations using radial basis functions  

NASA Astrophysics Data System (ADS)

In this paper, we propose an effective numerical method for solving nonlinear Volterra partial integro-differential equations. These equations include the partial differentiations of an unknown function and the integral term containing the unknown function as the "memory" of system. Radial basis functions and finite difference method as the main techniques play the important role to reduce a nonlinear partial integro-differential equation to a linear system of equations. Some examples are demonstrated to describe the method. Numerical results confirm the validity and efficiency of the presented method.

Avazzadeh, Z.; Rizi, Z. Beygi; Ghaini, F. M. Maalek; Loghmani, G. B.

2011-06-01

419

Loss of Myt1 function partially compromises endocrine islet cell differentiation and pancreatic physiological function in the mouse.  

PubMed

Myelin transcription factor 1 (Myt1) is one of the three vertebrate C2HC-type zinc finger transcription factors that include Myt1 (Nzf1), Myt1L (Png1), and Myt3 (Nzf3, St18). All three paralogs are widely expressed in developing neuronal cells. Yet their function for mammalian development has not been investigated directly. Here we report that only Myt1 is expressed in the embryonic pancreas, in both endocrine progenitors and differentiated islet cells. Myt1(-/-) animals die postnatally, likely due to confounding effects in multiple tissues. The endocrine tissues in the embryonic Myt1(-/-) pancreas contained abnormal islet cells that expressed multiple hormones; although hormone levels were normal. We also created pancreas-specific Myt1 knockout mice. These mutant animals had no obvious physical defects from their wild-type littermates. Male mutant animals had reduced glucose-clearing abilities and abnormal multi-hormone-expressing cells present in their endocrine islets. In addition, they also had reduced Glut2 expression, and attenuated glucose-induced insulin secretion in the adult islets. Surprisingly, the expression of the Myt1 paralogs, Myt1l and Myt3, was induced in the embryonic Myt1(-/-) pancreas. The consequences of Myt1 inactivation in the developing pancreas could be masked by activation of its paralogs, Myt1l and Myt3. These findings suggest Myt1 is involved in proper endocrine differentiation and function. PMID:17928203

Wang, Sui; Zhang, Jia; Zhao, Aizhen; Hipkens, Susan; Magnuson, Mark A; Gu, Guoqiang

2007-01-01

420

Staphylococcus aureus and Staphylococcus epidermidis peptide pheromones produced by the accessory gene regulator agr system  

Microsoft Academic Search

The accessory gene regulator (agr) system of staphylococci regulates the expression of virulence factors in response to cell density. The extracellular signaling molecule encoded by this system is a thiolactone-containing pheromone peptide whose primary sequence varies among staphylococcal strains. A post-translational modification of the peptide is believed to be carried out by an enzyme with a novel function, AgrB. Staphylococcal

Michael Otto

2001-01-01

421

Effect of RGD-functionalization and stiffness modulation of polyelectrolyte multilayer films on muscle cell differentiation  

PubMed Central

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

Gribova, Varvara; Gauthier-Rouvière, Cécile; Albigès-Rizo, Corinne; Auzely-Velty, Rachel; Picart, Catherine

2014-01-01

422

Effect of RGD functionalization and stiffness modulation of polyelectrolyte multilayer films on muscle cell differentiation.  

PubMed

Skeletal muscle tissue engineering holds promise for the replacement of muscle damaged by injury and for the treatment of muscle diseases. Although arginylglycylaspartic acid (RGD) substrates have been widely explored in tissue engineering, there have been no studies 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 increasing film stiffness could both induce cell adhesion, but the integrins involved in adhesion were different in the case of soft and stiff films. Soft films with RGD peptide appeared to be the most appropriate substrate for myogenic differentiation, while the stiff PLL/PGA films induced significant cell migration and proliferation and inhibited myogenic differentiation. ROCK kinase was found to be involved in the myoblast response to the different films. Indeed, its inhibition was sufficient to rescue 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 the mechanical and biochemical properties of multilayer films. This study emphasizes the advantage of soft PLL/PGA films presenting the RGD peptide in terms of myogenic differentiation. This soft RGD-presenting film may be further used as a coating of various polymeric scaffolds for muscle tissue engineering. PMID:23261924

Gribova, Varvara; Gauthier-Rouvière, Cécile; Albigès-Rizo, Corinne; Auzely-Velty, Rachel; Picart, Catherine

2013-05-01

423

Histamine suppresses epidermal keratinocyte differentiation and impairs skin barrier function in a human skin model  

PubMed Central

Background Defects in keratinocyte differentiation and skin barrier are important features of inflammatory skin diseases like atopic dermatitis. Mast cells and their main mediator histamine are abundant in inflamed skin and thus may contribute to disease pathogenesis. Methods Human primary keratinocytes were cultured under differentiation-promoting conditions in the presence and absence of histamine, histamine receptor agonists and antagonists. The expression of differentiation-associated genes and epidermal junction proteins was quantified by real-time PCR, Western blot, and immunofluorescence labeling. The barrier function of human skin models was tested by the application of biotin as tracer molecule. Results The addition of histamine to human keratinocyte cultures and organotypic skin models reduced the expression of the differentiation-associated proteins keratin 1/10, filaggrin, and loricrin by 80–95%. Moreover, the addition of histamine to skin models resulted in the loss of the granular layer and thinning of the epidermis and stratum corneum by 50%. The histamine receptor H1R agonist, 2-pyridylethylamine, suppressed keratinocyte differentiation to the same extent as did histamine. Correspondingly, cetirizine, an antagonist of H1R, virtually abrogated the effect of histamine. The expression of tight junction proteins zona occludens-1, occludin, claudin-1, and claudin-4, as well as that of desmosomal junction proteins corneodesmosin and desmoglein-1, was down-regulated by histamine. The tracer molecule biotin readily penetrated the tight junction barrier of skin cultures grown in the presence of histamine, while their diffusion was completely blocked in nontreated controls. Conclusions Our findings suggest a new mechanism by which mast cell activation and histamine release contribute to skin barrier defects in inflammatory skin diseases. PMID:23157658

Gschwandtner, M; Mildner, M; Mlitz, V; Gruber, F; Eckhart, L; Werfel, T; Gutzmer, R; Elias, P M; Tschachler, E

2013-01-01

424

Differentiating the stem cell pool of human hair follicle outer root sheath into functional melanocytes.  

PubMed

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. PMID:25173171

Schneider, Marie; Dieckmann, Christina; Rabe, Katrin; Simon, Jan-Christoph; Savkovic, Vuk

2014-01-01

425

Growth and differentiation factor-5 contributes to the structural and functional maintenance of the intervertebral disc.  

PubMed

Intervertebral disc degeneration (IDD) is a widely recognized contributor to low back pain (LBP). The Prevention or reversal of IDD is a potential treatment for LBP. Unfortunately, current treatments for IDD are aimed at relieving symptoms rather than regenerating disc structure or function. Recently, the injection of growth factors and mesenchymal stem cell (MSC) transplantation have been shown to be promising biological therapies for IDD. Growth factors stimulate the proliferation of and matrix synthesis by intervertebral disc (IVD) cells, leading to the regeneration of degenerative discs. Growth factors, hypoxia and co-culture with nucleus pulposus (NP) cells induce MSCs to differentiate toward an NP-like phenotype, which can increase the number of functional cells in the IVD or enhance the function of endogenous disc cells to facilitate IVD regeneration. Therefore, the emerging roles of growth factors in IVD regeneration have piqued the interest of researchers. Growth factors including transforming growth factor-? (TGF-?), fibroblast growth factor (FGF), insulin-like growth factor-1 (IGF-1) and growth and differentiation factor-5 (GDF-5), among others, have been demonstrated to enhance anabolism in IVD cells and to induce NP-like differentiation of MSCs. However, the injection of TGF, IGF and FGF into human IVDs may induce unwanted blood vessel ingrowth, which accelerates the process of IDD, the injection of GDF-5 may not have the same effect. This finding suggests that GDF-5 is a preferable growth factor for use in IDD treatment compared with TGF, IGF and FGF. The GDF-5 gene is one of the few growth factor genes that have been found to be associated with IDD thus far; moreover, the GDF-5 gene defects lead to collagen and proteoglycan abnormalities in discs in mice, suggesting that GDF-5 contributes to the structural and functional maintenance of the IVD. This review is focused on the functions of GDF-5 in the IVD and on the association between GDF-5 and a genetic predisposition to IDD. The effects of GDF-5 on IVD regeneration and on MSC differentiation are also discussed. GDF-5 plays a crucial role in the pathogenesis of IDD and is a promising therapeutic agent for IDD. Additionally, stem cell transplantation has been shown to be a promising biological therapy for IDD. PMID:25547527

Feng, Chencheng; Liu, Huan; Yang, Yang; Huang, Bo; Zhou, Yue

2015-01-01

426

Illustrating the Utility of Differential Bundle Functioning Analyses To Identify and Interpret Group Differences on Achievement Tests.  

ERIC Educational Resources Information Center

Describes some recent advances in the study of differential group performance and illustrates some of the ways that substantive analyses can be integrated with multidimensional, bundles-based statistical methods using test specifications to organize the analyses. Highlights some future directions for the analysis of differential item functioning.…

Gierl, Mark J.; Bisanz, Jeffrey; Bisanz, Gay L.; Boughton, Keith A.; Khaliq, Shameem Nyla

2001-01-01

427

Accessory Gene Regulator Locus of Staphylococcus intermedius  

PubMed Central

The accessory gene regulator (agr) locus, a candidate system for the regulation of the production of virulence factors in Staphylococcus intermedius, has been characterized. Using PCR-based genome walking, we have obtained the first complete sequence (3,436 bp) of the accessory gene regulator (agr) gene in this organism. Sequence analysis of the agr gene has identified five open reading frames (ORFs), agrB, agrD, agrC, agrA, and hld. The translated ORF contained amino acid motifs characteristic of the response regulator and histidine protein kinase signal transducer of the classic two-component regulatory system. Sequencing of the agrD PCR products amplified from DNA from 20 different isolates has facilitated detection of genetic variation in the putative autoinducing peptide (AIP) within the agr gene of S. intermedius, revealing the presence of at least three agr specificity groups within this species. Classification of the agr gene from S. intermedius was supported by phylogenetic analysis. Real-time PCR also revealed that the effector molecule of the agr system, RNAIII, was regulated in an autocrine manner in S. intermedius and demonstrated positive correlation with the temporal gene expression patterns of luk and entC. Transcription of RNAIII was also dependent on self secreted cues. Cyclic self and nonself peptides were synthesized on the basis of the novel AIPs produced by S. intermedius, which lack the cysteine necessary to form the thiolactone ring in analogous peptides from Staphylococcus aureus and Staphylococcus epidermidis. Experiments with these synthetic cyclic peptides indicated that self peptides led to up-regulation of RNAIII—findings in support of the assumption that activation of the agr gene is initiated by growth- and species-specific factors generated during bacterial growth. PMID:16622233

Sung, Julia M. L.; Chantler, Peter D.; Lloyd, David H.

2006-01-01

428

Differentially disrupted functional connectivity of the subregions of the inferior parietal lobule in Alzheimer's disease.  

PubMed

Recent research on Alzheimer's disease (AD) has shown that the altered structure and function of the inferior parietal lobule (IPL) provides a promising indicator of AD. However, little is known about the functional connectivity of the IPL subregions in AD subjects. In this study, we collected resting-state functional magnetic resonance imaging data from 32 AD patients and 38 healthy controls. We defined seven subregions of the IPL according to probabilistic cytoarchitectonic atlases and mapped the whole-brain resting-state functional connectivity for each subregion. Using hierarchical clustering analysis, we identified three distinct functional connectivity patterns of the IPL subregions: the anterior IPL connected with the sensorimotor network (SMN) and salience network (SN); the central IPL had connectivity with the executive-control network (ECN); and the posterior IPL exhibited connections with the default-mode network (DMN). Compared with the controls, the AD patients demonstrated distinct disruptive patterns of the IPL subregional connectivity with these different networks (SMN, SN, ECN and DMN), which suggests the impairment of the functional integration in the IPL. Notably, we also observed that the IPL subregions showed increased connectivity with the posterior part of the DMN in AD patients, which potentially indicates a compensatory mechanism. Finally, these abnormal IPL functional connectivity changes were closely associated with cognitive performance. Collectively, we show that the subregions of the IPL present distinct functional connectivity patterns with various functional networks that are differentially impaired in AD patients. Our results also suggest that functional disconnection and compensation in the IPL may coexist in AD. PMID:24292325

Wang, Zhiqun; Xia, Mingrui; Dai, Zhengjia; Liang, Xia; Song, Haiqing; He, Yong; Li, Kuncheng

2015-03-01

429

Importance of renal depth correction for quantitation of differential renal function  

SciTech Connect

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.

Choi, H.; Kirchner, P.T.

1985-05-01

430

Interleukin-21 suppresses the differentiation and functions of T helper 2 cells.  

PubMed

T helper type 2 (Th2) cells, which produce interleukin-4 (IL-4), IL-5 and IL-13, control immunity to all forms of allergic inflammatory responses. Interleukin-21 (IL-21) reduces allergic symptoms in murine models and inhibits IL-4-induced IgE secretion by B cells. However, whether or not IL-21 directly affects Th2 cells, which leads to reduced allergic symptoms, is unclear. In this study, we investigated the effects of IL-21 on the differentiation and effector functions of Th2 cells. We found that IL-21 reduced the number of differentiated Th2 cells and these Th2 cells showed a diminished Th2 cytokine production. Interleukin-21 suppressed Th2 cytokine production of already polarized Th2 cells by down-regulation of transcription factor GATA-3. It also induced apoptosis of Th2 cells with decreased anti-apoptotic factor Bcl-2. Intranasal administration of IL-21 at the beginning of ovalbumin (OVA) sensitization or before OVA challenge decreased Th2 cytokines in the bronchoalveolar lavage fluid of OVA/alum-immunized allergic mice. In addition, the inhibitory effects of IL-21 on Th2 effector functions can also be found in allergic patients. Our results demonstrate that IL-21 suppresses the development of Th2 cells and functions of polarized Th2 cells. Hence, the administration of IL-21 may be considered for use as a preventive and therapeutic approach when dealing with Th2-mediated allergic diseases. PMID:25351608

Lin, Pin-Yi; Jen, Hsiao-Yu; Chiang, Bor-Luen; Sheu, Fuu; Chuang, Ya-Hui

2015-04-01

431

Prostate cell differentiation status determines transient receptor potential melastatin member 8 channel subcellular localization and function.  

PubMed

In recent years, the transient receptor potential melastatin member 8 (TRPM8) channel has emerged as a promising prognostic marker and putative therapeutic target in prostate cancer (PCa). However, the mechanisms of prostate-specific regulation and functional evolution of TRPM8 during PCa progression remain unclear. Here we show, for the first time to our knowledge, that only secretory mature differentiated human prostate primary epithelial (PrPE) luminal cells expressed functional plasma membrane TRPM8 ((PM)TRPM8) channels. Moreover, PCa epithelial cells obtained from in situ PCa were characterized by a significantly stronger (PM)TRPM8-mediated current than that in normal cells. This (PM)TRPM8 activity was abolished in dedifferentiated PrPE cells that had lost their luminal secretory phenotype. However, we found that in contrast to (PM)TRPM8, endoplasmic reticulum TRPM8 ((ER)TRPM8) retained its function as an ER Ca(2+) release channel, independent of cell differentiation. We hypothesize that the constitutive activity of (ER)TRPM8 may result from the expression of a truncated TRPM8 splice variant. Our study provides insight into the role of TRPM8 in PCa progression and suggests that TRPM8 is a potentially attractive target for therapeutic intervention: specific inhibition of either (ER)TRPM8 or (PM)TRPM8 may be useful, depending on the stage and androgen sensitivity of the targeted PCa. PMID:17510704

Bidaux, Gabriel; Flourakis, Matthieu; Thebault, Stéphanie; Zholos, Alexander; Beck, Benjamin; Gkika, Dimitra; Roudbaraki, Morad; Bonnal, Jean-Louis; Mauroy, Brigitte; Shuba, Yaroslav; Skryma, Roman; Prevarskaya, Natalia

2007-06-01

432

Prostate cell differentiation status determines transient receptor potential melastatin member 8 channel subcellular localization and function  

PubMed Central

In recent years, the transient receptor potential melastatin member 8 (TRPM8) channel has emerged as a promising prognostic marker and putative therapeutic target in prostate cancer (PCa). However, the mechanisms of prostate-specific regulation and functional evolution of TRPM8 during PCa progression remain unclear. Here we show, for the first time to our knowledge, that only secretory mature differentiated human prostate primary epithelial (PrPE) luminal cells expressed functional plasma membrane TRPM8 (PMTRPM8) channels. Moreover, PCa epithelial cells obtained from in situ PCa were characterized by a significantly stronger PMTRPM8-mediated current than that in normal cells. This PMTRPM8 activity was abolished in dedifferentiated PrPE cells that had lost their luminal secretory phenotype. However, we found that in contrast to PMTRPM8, endoplasmic reticulum TRPM8 (ERTRPM8) retained its function as an ER Ca2+ release channel, independent of cell differentiation. We hypothesize that the constitutive activity of ERTRPM8 may result from the expression of a truncated TRPM8 splice variant. Our study provides insight into the role of TRPM8 in PCa progression and suggests that TRPM8 is a potentially attractive target for therapeutic intervention: specific inhibition of either ERTRPM8 or PMTRPM8 may be useful, depending on the stage and androgen sensitivity of the targeted PCa. PMID:17510704

Bidaux, Gabriel; Flourakis, Matthieu; Thebault, Stéphanie; Zholos, Alexander; Beck, Benjamin; Gkika, Dimitra; Roudbaraki, Morad; Bonnal, Jean-Louis; Mauroy, Brigitte; Shuba, Yaroslav; Skryma, Roman; Prevarskaya, Natalia

2007-01-01

433

Differential Regulation of Neutrophil CD18 Integrin Function by Di-and Tri-Valent Cations: Manganese vs. Gadolinium  

E-print Network

Differential Regulation of Neutrophil CD18 Integrin Function by Di- and Tri-Valent Cations 2008) Abstract--Affinity regulation of integrin function plays an important role during both leukocyte) in regulating leukocyte CD18-integrin function. We observed that: (i) Both cations prolonged neutrophil

Simon, Scott I.

434

Breakage-fusion-bridge cycles and large insertions contribute to the rapid evolution of accessory chromosomes in a fungal pathogen.  

PubMed

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 this and other fungal pathogens. PMID:23785303

Croll, Daniel; Zala, Marcello; McDonald, Bruce A

2013-06-01

435

Breakage-fusion-bridge Cycles and Large Insertions Contribute to the Rapid Evolution of Accessory Chromosomes in a Fungal Pathogen  

PubMed Central

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 this and other fungal pathogens. PMID:23785303

Croll, Daniel; Zala, Marcello; McDonald, Bruce A.

2013-01-01

436

Determination of Helium - Helium Potential Energy Function by Inversion of Differential Cross Sections  

NASA Astrophysics Data System (ADS)

The He - He interaction at short range was studied via a detailed examination of Firsov's inversion theory and the various conditions to which it is subject. Experimental differential cross sections at 0.5 keV and 1.0 keV determined by Abrahams and Peterson were inverted to obtain He(,2) ground state potential energies. It was found that the practical application of Firsov's theory is subject to three conditions. These conditions result from (1) difficulties associated with the absolute measurement of differential cross sections, (2) lack of experimental measurements for scattering at angles less than some minimum angle, and (3) inelastic scattering contributions to the cross section at large scattering angles. A practical procedure for inversion of experimental cross sections was investigated. This procedure explicitly treats the three conditions cited above. It was found that experimental differential cross sections must be corrected for the effect of finite scattering geometry. A procedure for effecting this correction was developed. A semi-theoretical He(,2) potential energy function was determined by slightly adjusting the scale of distance for a potential energy function obtained by inversion such that at 0.529 A the potential energy is 25.0 eV. Electronic energies derived from this potential energy function are within 1.0 eV of ab initio He(,2) electronic energies over the range 0.5 A to 1.0 A and are not in conflict with the variation theorem of quantum mechanics. This result supports the Born-Oppenheimer description of He - He scattering. It was observed that the equations describing both direct and inverse classical scattering consist of integrals which can be reduced to the form. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). A quadrature formula based on expansion of f(x,y) in shifted Chebyshev polynomials has been derived for evaluating this integral.

Lambrakos, Samuel George

437

Differential Abundance of Microbial Functional Groups along the Elevation Gradient from the Coast to the Luquillo Mountains  

EPA Science Inventory

Microbial communities respond to multiple abiotic and biotic factors that change along elevation gradients. We compare changes in microbial community composition in soil and review previous research on differential abundance of microbial functional groups along an elevation gradi...

438

A multiple exp-function method for nonlinear differential equations and its application  

E-print Network

A multiple exp-function method to exact multiple wave solutions of nonlinear partial differential equations is proposed. The method is oriented towards ease of use and capability of computer algebra systems, and provides a direct and systematical solution procedure which generalizes Hirota's perturbation scheme. With help of Maple, an application of the approach to the $3+1$ dimensional potential-Yu-Toda-Sasa-Fukuyama equation yields exact explicit 1-wave and 2-wave and 3-wave solutions, which include 1-soliton, 2-soliton and 3-soliton type solutions. Two cases with specific values of the involved parameters are plotted for each of 2-wave and 3-wave solutions.

Wen-Xiu Ma; Tingwen Huang; Yi Zhang

2010-10-16

439

Sensing the immune microenvironment to coordinate T cell metabolism, differentiation & function  

PubMed Central

Mounting an adaptive immune response is bioenergetically demanding. As a result, T cell activation coincides with profound changes in cellular metabolism that must be coordinated with instructive signals from cytokine and costimulatory receptors to generate an immune response. Studies examining the intimate link between metabolism and immune function have revealed that different types of T cells have distinct metabolic profiles. Data is emerging that place mTOR, an evolutionarily conserved serine-threonine kinase, as a central integrator of these processes. In this review, we will discuss the role of mTOR in determining both CD4 and CD8 T cell metabolism, differentiation, and trafficking. PMID:23332779

Heikamp, Emily B.; Powell, Jonathan D.

2013-01-01

440

Notch2 receptor signaling controls functional differentiation of dendritic cells in the spleen and intestine.  

PubMed

Dendritic cells (DCs) in tissues and lymphoid organs comprise distinct functional subsets that differentiate in situ from circulating progenitors. Tissue-specific signals that regulate DC subset differentiation are poorly understood. We report that DC-specific deletion of the Notch2 receptor caused a reduction of DC populations in the spleen. Within the splenic CD11b(+) DC subset, Notch signaling blockade ablated a distinct population marked by high expression of the adhesion molecule Esam. The Notch-dependent Esam(hi) DC subset required lymphotoxin beta receptor signaling, proliferated in situ, and facilitated CD4(+) T cell priming. The Notch-independent Esam(lo) DCs expressed monocyte-related genes and showed superior cytokine responses. In addition, Notch2 deletion led to the loss of CD11b(+)CD103(+) DCs in the intestinal lamina propria and to a corresponding decrease of IL-17-producing CD4(+) T cells in the intestine. Thus, Notch2 is a common differentiation signal for T cell-priming CD11b(+) DC subsets in the spleen and intestine. PMID:22018469

Lewis, Kanako L; Caton, Michele L; Bogunovic, Milena; Greter, Melanie; Grajkowska, Lucja T; Ng, Dennis; Klinakis, Apostolos; Charo, Israel F; Jung, Steffen; Gommerman, Jennifer L; Ivanov, Ivaylo I; Liu, Kang; Merad, Miriam; Reizis, Boris

2011-11-23

441

Notch2 receptor signaling controls functional differentiation of dendritic cells in the spleen and intestine  

PubMed Central

Summary Dendritic cells (DCs) in tissues and lymphoid organs comprise distinct functional subsets that differentiate in situ from circulating progenitors. Tissue-specific signals that regulate DC subset differentiation are poorly understood. We report that DC-specific deletion of the Notch2 receptor caused a reduction of DC populations in the spleen. Within the splenic CD11b+ DC subset, Notch signaling blockade ablated a distinct population marked by high expression of the adhesion molecule Esam. The Notch-dependent Esamhi DC subset required lymphotoxin beta receptor signaling, proliferated in situ and facilitated CD4+ T cell priming. The Notch-independent Esamlo DCs expressed monocyte-related genes and showed superior cytokine responses. In addition, Notch2 deletion led to the loss of CD11b+ CD103+ DCs in the intestinal lamina propria and to a corresponding decrease of IL-17-producing CD4+ T cells in the intestine. Thus, Notch2 is a common differentiation signal for T cell-priming CD11b+ DC subsets in the spleen and intestine. PMID:22018469

Lewis, Kanako L.; Caton, Michele L.; Bogunovic, Milena; Greter, Melanie; Grajkowska, Lucja T.; Ng, Dennis; Klinakis, Apostolos; Charo, Israel F.; Jung, Steffen; Gommerman, Jennifer L.; Ivanov, Ivaylo I.; Liu, Kang; Merad, Miriam; Reizis, Boris

2011-01-01

442

Poly(norepinephrine) as a functional bio-interface for neuronal differentiation on electrospun fibers.  

PubMed

Based on the catecholic chemistry of a mussel inspired coating, norepinephrine (NE), a catecholamine found both in neurotransmitters and mussel adhesive proteins, was for the first time applied as a unique bio-interface integrating multi-functions facilitating PC12 neuron-like differentiation. A uniform, ultra-smooth pNE coating was achieved on electrospun submicron PLCL fibers, proven by surface characterization. The introduced catechol groups from pNE were further used to not only anchor collagen to enhance cell adhesion but also localize nerve growth factor to promote neuron-like differentiation. The obtained pNE-collagen coating was found to be a superior substrate for PC12 differentiation, confirmed by both cellular toxicity/viability assays and immunochemical staining. The aligned PLCL fiber conformation further steered neurite formation along the fiber direction and contributed to neurite extension and increased the number of neurites per cell body. This facile pNE coating might lead to a more efficient use of growth factor, drugs and other bioactive molecules with lower loading dosage and sustained activity resulting in enhanced therapeutic effects and decreased adverse effects. PMID:25766518

Taskin, Mehmet Berat; Xu, Ruodan; Zhao, Huiling; Wang, Xueqin; Dong, Mingdong; Besenbacher, Flemming; Chen, Menglin

2015-04-14

443

Differential Density Statistics of the Galaxy Distribution and the Luminosity Function  

NASA Astrophysics Data System (ADS)

This paper uses data obtained from the galaxy luminosity function (LF) to calculate two types of radial number density statistics of the galaxy distribution as discussed in Ribeiro, namely, the differential density ? and the integral differential density ?*. By applying the theory advanced by Ribeiro & Stoeger, which connects the relativistic cosmology number counts with the astronomically derived LF, the differential number counts dN/dz are extracted from the LF and used to calculate both ? and ?* with various cosmological distance definitions, namely, area distance, luminosity distance, galaxy area distance, and redshift distance. LF data are taken from the CNOC2 galaxy redshift survey, and ? and ?* are calculated for two cosmological models: Einstein-de Sitter and an ?m0=0.3, ??0=0.7 standard cosmology. The results confirm the strong dependency of both statistics on the distance definition, as predicted in Ribeiro, as well as showing that plots of ? and ?* against the luminosity and redshift distances indicate that the CNOC2 galaxy distribution follows a power-law pattern for redshifts higher than 0.1. These findings support Ribeiro's theoretical proposition that using different cosmological distance measures in statistical analyses of galaxy surveys can lead to significant ambiguity in drawing conclusions about the behavior of the observed large-scale distribution of galaxies.

Albani, V. V. L.; Iribarrem, A. S.; Ribeiro, M. B.; Stoeger, W. R.

2007-03-01

444

Differential PAX3 functions in normal skin melanocytes and melanoma cells  

SciTech Connect

Highlights: {yields} PAX3 retains embryonic roles in adult melanocytes and melanoma cells. {yields} Promotes 'stem' cell-like phenotype via NES and SOX9 in both cells types. {yields} Regulates melanoma and melanocyte migration through MCAM and CSPG4. {yields} PAX3 regulates melanoma but not melanocyte proliferation via TPD52. {yields} Regulates melanoma cell (but not melanocyte) survival via BCL2L1 and PTEN. -- Abstract: The PAX3 transcription factor is the key regulator of melanocyte development during embryogenesis and is also frequently found in melanoma cells. While PAX3 is known to regulate melanocyte differentiation, survival, proliferation and migration during development, it is not clear if its function is maintained in adult melanocytes and melanoma cells. To clarify this we have assessed which genes are targeted by PAX3 in these cells. We show here that similar to its roles in development, PAX3 regulates complex differentiation networks in both melanoma cells and melanocytes, in order to maintain cells as 'stem' cell-like (via NES and SOX9). We show also that mediators of migration (MCAM and CSPG4) are common to both cell types but more so in melanoma cells. By contrast, PAX3-mediated regulation of melanoma cell proliferation (through TPD52) and survival (via BCL2L1 and PTEN) differs from that in melanocytes. These results suggest that by controlling cell proliferation, survival and migration as well as maintaining a less differentiated 'stem' cell like phenotype, PAX3 may contribute to melanoma development and progression.

Medic, Sandra [School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Perth, WA (Australia)] [School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Perth, WA (Australia); Rizos, Helen [Westmead Institute for Cancer Research and Melanoma Institute of Australia, University of Sydney at Westmead Millennium Institute, Westmead, NSW (Australia)] [Westmead Institute for Cancer Research and Melanoma Institute of Australia, University of Sydney at Westmead Millennium Institute, Westmead, NSW (Australia); Ziman, Mel, E-mail: m.ziman@ecu.edu.au [School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Perth, WA (Australia) [School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Perth, WA (Australia); School of Pathology and Laboratory Medicine, University of Western Australia, Perth, WA (Australia)

2011-08-12

445

The accessory subunit of mitochondrial DNA polymerase c determines the DNA content of mitochondrial nucleoids in human cultured cells  

Microsoft Academic Search

The accessory subunit of mitochondrial DNA poly- merase c, POLGb, functions as a processivity factor in vitro. Here we show POLGb has additional roles in mitochondrial DNA metabolism. Mitochondrial DNA is arranged in nucleoprotein complexes, or nucleoids, which often contain multiple copies of the mitochondrial genome. Gene-silencing of POLGb increased nucleoid numbers, whereas over- expression of POLGb reduced the number

M. Di Re; H. Sembongi; J. He; A. Reyes; T. Yasukawa; P. Martinsson; L. J. Bailey; S. Goffart; J. D. Boyd-Kirkup; T. S. Wong; A. R. Fersht; J. N. Spelbrink; I. J. Holt

446

Differential tissue-regulation of myostatin genes in the teleost fish Lates calcarifer in response to fasting. Evidence for functional differentiation  

Microsoft Academic Search

Gene or genome duplication is a fundamental evolutionary mechanism leading towards the origin of new genes, or gene functions. Myostatin (MSTN) is a negative regulator of muscle growth that in teleost fish, as a result of genome duplication, is present in double copy. This study provides evidence of differentiation of MSTN paralogs in fish by comparatively exploring their tissue-regulation in

C. De Santis; D. R. Jerry

2011-01-01

447

Representation and transformation of sensory information in the mouse accessory olfactory system  

PubMed Central

In mice, nonvolatile social cues are detected and analyzed by the accessory olfactory system (AOS). Here we provide a first view of information processing in the AOS with respect to individual chemical cues. 12 sulfated steroids, recently-discovered mouse AOS ligands, caused widespread activity among vomeronasal sensory neurons (VSNs), yet VSN responses clustered into a small number of repeated functional patterns or processing streams. Downstream neurons in the accessory olfactory bulb (AOB) responded to these ligands with enhanced signal/noise compared to VSNs. Whereas the dendritic connectivity of AOB mitral cells suggests the capacity for broad integration, most sulfated steroid responses were well-modeled by linear excitatory drive from just one VSN processing stream. However, a significant minority demonstrated multi-stream integration. Most VSN excitation patterns were also observed in the AOB, but excitation by estradiol sulfate processing streams was rare, suggesting AOB circuit organization is specific to the biological relevance of sensed cues. PMID:20453853

Meeks, Julian P.; Arnson, Hannah A.; Holy, Timothy E.

2010-01-01

448

Spinal accessory nerve palsy as a cause of pain after whiplash injury: case report.  

PubMed

Spinal accessory nerve injury is most commonly reported following surgery in and around the posterior cervical triangle. Pain, impaired ability to raise the ipsilateral shoulder, and scapular winging on abduction of the arm are the most frequently noted clinical manifestations. We report the case of a collegiate swimmer who developed left-sided neck and shoulder pain secondary to a spinal accessory nerve palsy (SANP) after a "whiplash injury," which we believe to be the first such reported case in the English language literature. We review the clinical manifestations, diagnostic pitfalls, and therapeutic approaches to SANP. A high index of suspicion for SANP following whiplash-type injury will ensure its earlier detection and treatment and improve the chances of a better functional outcome. PMID:9654838

Bodack, M P; Tunkel, R S; Marini, S G; Nagler, W

1998-05-01

449

A New Integrated Onboard Charger and Accessory Power Converter for Plug-in Electric Vehicles  

SciTech Connect

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.

Su, Gui-Jia [ORNL; Tang, Lixin [ORNL

2014-01-01

450

Instrumented Functional Reach Test Differentiates Individuals at High Risk for Parkinson’s Disease from Controls  

PubMed Central

The functional reach (FR) test as a complex measure of balance including limits of stability has been proven to differentiate between patients with Parkinson’s disease (PD) and controls (CO). Recently, it has been shown that the instrumentation of the FR (iFR) with a wearable sensor may increase this diagnostic accuracy. This cross-sectional study aimed at investigating whether the iFR has the potential to differentiate individuals with high risk for PD (HRPD) from CO, as the delineation of such individuals would allow for, e.g., early neuromodulation. Thirteen PD patients, 13 CO, and 31 HRPD were investigated. HRPD was defined by presence of an enlarged area of hyperechogenicity in the mesencephalon on transcranial sonography and either one motor sign or two risk and prodromal markers of PD. All participants were asked to reach with their right arm forward as far as possible and hold this position for 10?s. During this period, sway parameters were assessed with an accelerometer (Dynaport, McRoberts) worn at the lower back. Extracted parameters that differed significantly between PD patients and CO in our cohort [FR distance (shorter in PD), anterior–posterior and mediolateral acceleration (both lower in PD)] as well as JERK, which has been shown to differentiate HRPD from CO and PD in a previous study, were included in a model, which was then used to differentiate HRPD from CO. The model yielded an area under the curve of 0.77, with a specificity of 85%, and a sensitivity of 74%. These results suggest that the iFR can contribute to an assessment panel focusing on the definition of HRPD individuals. PMID:25386137

Hasmann, Sandra E.; Berg, Daniela; Hobert, Markus A.; Weiss, David; Lindemann, Ulrich; Streffer, Johannes; Liepelt-Scarfone, Inga; Maetzler, Walter

2014-01-01

451

Instrumented functional reach test differentiates individuals at high risk for Parkinson's disease from controls.  

PubMed

The functional reach (FR) test as a complex measure of balance including limits of stability has been proven to differentiate between patients with Parkinson's disease (PD) and controls (CO). Recently, it has been shown that the instrumentation of the FR (iFR) with a wearable sensor may increase this diagnostic accuracy. This cross-sectional study aimed at investigating whether the iFR has the potential to differentiate individuals with high risk for PD (HRPD) from CO, as the delineation of such individuals would allow for, e.g., early neuromodulation. Thirteen PD patients, 13 CO, and 31 HRPD were investigated. HRPD was defined by presence of an enlarged area of hyperechogenicity in the mesencephalon on transcranial sonography and either one motor sign or two risk and prodromal markers of PD. All participants were asked to reach with their right arm forward as far as possible and hold this position for 10?s. During this period, sway parameters were assessed with an accelerometer (Dynaport, McRoberts) worn at the lower back. Extracted parameters that differed significantly between PD patients and CO in our cohort [FR distance (shorter in PD), anterior-posterior and mediolateral acceleration (both lower in PD)] as well as JERK, which has been shown to differentiate HRPD from CO and PD in a previous study, were included in a model, which was then used to differentiate HRPD from CO. The model yielded an area under the curve of 0.77, with a specificity of 85%, and a sensitivity of 74%. These results suggest that the iFR can contribute to an assessment panel focusing on the definition of HRPD individuals. PMID:25386137

Hasmann, Sandra E; Berg, Daniela; Hobert, Markus A; Weiss, David; Lindemann, Ulrich; Streffer, Johannes; Liepelt-Scarfone, Inga; Maetzler, Walter

2014-01-01

452

A novel application of radial basis functions for solving a model of first-order integro-ordinary differential equation  

NASA Astrophysics Data System (ADS)

In this paper two common collocation approaches based on radial basis functions (RBFs) have been considered; one is computed through the differentiation process (DRBF) and the other one is computed through the integration process (IRBF). We investigate these two approaches on the Volterra's Population Model which is an integro-differential equation without converting it to an ordinary differential equation. To solve the problem, we use four well-known radial basis functions: Multiquadrics (MQ), Inverse multiquadrics (IMQ), Gaussian (GA) and Hyperbolic secant (sech) which is a newborn RBF. Numerical results and residual norm (?R(t)?2) show good accuracy and rate of convergence of two common approaches.

Parand, K.; Abbasbandy, S.; Kazem, S.; Rad, J. A.

2011-11-01

453

Vascular endothelial and endocardial progenitors differentiate as cardiomyocytes in the absence of Etsrp/Etv2 function  

PubMed Central

Previous studies have suggested that embryonic vascular endothelial, endocardial and myocardial lineages originate from multipotential cardiovascular progenitors. However, their existence in vivo has been debated and molecular mechanisms that regulate specification of different cardiovascular lineages are poorly understood. An ETS domain transcription factor Etv2/Etsrp/ER71 has been recently established as a crucial regulator of vascular endothelial differentiation in zebrafish and mouse embryos. In this study, we show that etsrp-expressing vascular endothelial/endocardial progenitors differentiate as cardiomyocytes in the absence of Etsrp function during zebrafish embryonic development. Expression of multiple endocardial specific markers is absent or greatly reduced in Etsrp knockdown or mutant embryos. We show that Etsrp regulates endocardial differentiation by directly inducing endocardial nfatc1 expression. In addition, Etsrp function is required to inhibit myocardial differentiation. In the absence of Etsrp function, etsrp-expressing endothelial and endocardial progenitors initiate myocardial marker hand2 and cmlc2 expression. Furthermore, Foxc1a function and interaction between Foxc1a and Etsrp is required to initiate endocardial development, but is dispensable for the inhibition of myocardial differentiation. These results argue that Etsrp initiates endothelial and endocardial, and inhibits myocardial, differentiation by two distinct mechanisms. Our findings are important for the understanding of genetic pathways that control cardiovascular differentiation during normal vertebrate development and will also greatly contribute to the stem cell research aimed at regenerating heart tissues. PMID:21989916

Palencia-Desai, Sharina; Kohli, Vikram; Kang, Jione; Chi, Neil C.; Black, Brian L.; Sumanas, Saulius

2011-01-01

454

Transcription. CTCF establishes discrete functional chromatin domains at the Hox clusters during differentiation.  

PubMed

Polycomb and Trithorax group proteins encode the epigenetic memory of cellular positional identity by establishing inheritable domains of repressive and active chromatin within the Hox clusters. Here we demonstrate that the CCCTC-binding factor (CTCF) functions to insulate these adjacent yet antagonistic chromatin domains during embryonic stem cell differentiation into cervical motor neurons. Deletion of CTCF binding sites within the Hox clusters results in the expansion of active chromatin into the repressive domain. CTCF functions as an insulator by organizing Hox clusters into spatially disjoint domains. Ablation of CTCF binding disrupts topological boundaries such that caudal Hox genes leave the repressed domain and become subject to transcriptional activation. Hence, CTCF is required to insulate facultative heterochromatin from impinging euchromatin to produce discrete positional identities. PMID:25722416

Narendra, Varun; Rocha, Pedro P; An, Disi; Raviram, Ramya; Skok, Jane A; Mazzoni, Esteban O; Reinberg, Danny

2015-02-27

455

Differential effect of calsequestrin ablation on structure and function of fast and slow skeletal muscle fibers.  

PubMed

We compared structure and function of EDL and Soleus muscles in adult (4-6?m) mice lacking both Calsequestrin (CASQ) isoforms, the main SR Ca²?-binding proteins. Lack of CASQ induced ultrastructural alterations in ~30% of Soleus fibers, but not in EDL. Twitch time parameters were prolonged in both muscles, although tension was not reduced. However, when stimulated for 2?sec at 100?hz, Soleus was able to sustain contraction, while in EDL active tension declined by 70-80%. The results presented in this paper unmask a differential effect of CASQ1&2 ablation in fast versus slow fibers. CASQ is essential in EDL to provide large amount of Ca²? released from the SR during tetanic stimulation. In contrast, Soleus deals much better with lack of CASQ because slow fibers require lower Ca²? amounts and slower cycling to function properly. Nevertheless, Soleus suffers more severe structural damage, possibly because SR Ca²? leak is more pronounced. PMID:21941434

Paolini, Cecilia; Quarta, Marco; D'Onofrio, Laura; Reggiani, Carlo; Protasi, Feliciano

2011-01-01

456

Identification of a Novel Cryptochrome Differentiating Domain Required for Feedback Repression in Circadian Clock Function*  

PubMed Central

Circadian clocks in mammals are based on a negative feedback loop in which transcriptional repression by the cryptochromes, CRY1 and CRY2, lies at the heart of the mechanism. Despite similarities in sequence, domain structure, and biochemical activity, they play distinct roles in clock function. However, detailed biochemical studies have not been straightforward and Cry function has not been examined in real clock cells using kinetic measurements. In this study, we demonstrate, through cell-based genetic complementation and real-time molecular recording, that Cry1 alone is able to maintain cell-autonomous circadian rhythms, whereas Cry2 cannot. Using this novel functional assay, we identify a cryptochrome differentiating ?-helical domain within the photolyase homology region (PHR) of CRY1, designated as CRY1-PHR(313–426), that is required for clock function and distinguishes CRY1 from CRY2. Contrary to speculation, the divergent carboxyl-terminal tail domain (CTD) is dispensable, but serves to modulate rhythm amplitude and period length. Finally, we identify the biochemical basis of their distinct function; CRY1 is a much more potent transcriptional repressor than CRY2, and the strength of repression by various forms of CRY proteins significantly correlates with rhythm amplitude. Taken together, our results demonstrate that CRY1-PHR(313–426), not the divergent CTD, is critical for clock function. These findings provide novel insights into the evolution of the diverse functions of the photolyase/cryptochrome family of flavoproteins and offer new opportunities for mechanistic studies of CRY function. PMID:22692217

Khan, Sanjoy K.; Xu, Haiyan; Ukai-Tadenuma, Maki; Burton, Brittany; Wang, Yongmei; Ueda, Hiroki R.; Liu, Andrew C.

2012-01-01

457

An analysis of differential item functioning by gender in the Learning Disability Screening Questionnaire (LDSQ).  

PubMed

The Learning Disability Screening Questionnaire (LDSQ; McKenzie & Paxton, 2006) was developed as a brief screen for intellectual disability. Although several previous studies have evaluated the LDSQ with respect to its utility as a clinical and research tool, no studies have considered the fairness of the test across males and females. In the current study we, therefore, used a multi-group item response theory approach to assess differential item functioning across gender in a sample of 211 males and 132 females assessed in clinical and forensic settings. Although the test did not show evidence of differential item functioning by gender, it was necessary to exclude one item due to estimation problems and to combine two very highly related items (concerning reading and writing ability) into a single literacy item Thus, in addition to being generally supportive of the utility of the LDSQ, our results also highlight possible areas of weakness in the tool and suggest possible amendments that could be made to test content to improve the test in future revisions. PMID:25677033

Murray, Aja Louise; Booth, Tom; McKenzie, Karen

2015-04-01

458

The numerical analysis of functional integral and integro-differential equations of Volterra type  

NASA Astrophysics Data System (ADS)

The qualitative and quantitative analysis of numerical methods for delay differential equations is now quite well understood, as reflected in the recent monograph by Bellen and Zennaro (2003). This is in remarkable contrast to the situation in the numerical analysis of functional equations, in which delays occur in connection with memory terms described by Volterra integral operators. The complexity of the convergence and asymptotic stability analyses has its roots in new `dimensions' not present in DDEs: the problems have distributed delays; kernels in the Volterra operators may be weakly singular; a second discretization step (approximation of the memory term by feasible quadrature processes) will in general be necessary before solution approximations can be computed.The purpose of this review is to introduce the reader to functional integral and integro-differential equations of Volterra type and their discretization, focusing on collocation techniques; to describe the `state of the art' in the numerical analysis of such problems; and to show that - especially for many `classical' equations whose analysis dates back more than 100 years - we still have a long way to go before we reach a level of insight into their discretized versions to compare with that achieved for DDEs.

Brunner, Hermann

459

Directed differentiation of human pluripotent stem cells into mature airway epithelia expressing functional CFTR protein  

PubMed Central

Cystic fibrosis (CF) is a fatal genetic disease caused by mutations in the CFTR (cystic fibrosis transmembrane conductance regulator) gene that regulates chloride and water transport across all epithelia and affects multiple organs including the lungs. Here we report an in vitro directed differentiation protocol for generating functional CFTR-expressing airway epithelia from human embryonic stem cells. Carefully timed treatment by exogenous growth factors that mimic endoderm developmental pathways in vivo followed by air-liquid interface culture results in maturation of patches of tight junction-coupled differentiated airway epithelial cells that demonstrate active CFTR transport function. As a proof-of-concept, treatment of CF patient induced pluripotent stem cells (iPSC)-derived epithelial cells with a novel small molecule compound to correct for the common CF-processing mutation resulted in enhanced plasma membrane localization of mature CFTR protein. Our study provides a method for generating patient-specific airway epithelial cells for disease modeling and in vitro drug testing. PMID:22922672

Wong, Amy P.; Bear, Christine E.; Chin, Stephanie; Pasceri, Peter; Thompson, Tadeo O.; Huan, Ling-Jun; Ratjen, Felix; Ellis, James; Rossant, Janet

2014-01-01

460

Morphological and functional differentiation of the surface epithelium of the bursa Fabricii in chicken.  

PubMed

Morphological and functional differentiation of the mucosal surface epithelium of the bursa Fabricii was studied in White Leghorn chicken fetuses and newly hatched chickens. First signs of differentiation towards two types of epithelial cells appeared on the thirteenth day of incubation: The apical cells of the epithelial buds projected towards the lumen, and an increase in the number of Golgi regions was observed in the epithelial cells between the buds. On day 15 the follicle-associated epithelium contained small apically situated vacuoles, and large mucin granules appeared in the interfollicular surface epithelium. Towards the day of hatching both epithelial cell types were arranged to a monolayered or pseudostratified cylindrical epithelium. The follicle-associated epithelium had invaginations and small vacuoles in the apical cytoplasm, whereas the interfollicular surface epithelium had numerous microvilli on its apical surface and large mucin granules in the apical cytoplasm. In functional studies, endocytosis of colloidal carbon was demonstrated in four out of ten 19-day fetuses and in all chickens studied immediately after hatching. PMID:697054

Naukkarinen, A; Arstila, A U; Sorvari, T E

1978-08-01

461

Structural and Mutational Analysis of Functional Differentiation between Synaptotagmins-1 and -7  

SciTech Connect

Synaptotagmins are known to mediate diverse forms of Ca{sup 2+}-triggered exocytosis through their C{sub 2} domains, but the principles underlying functional differentiation among them are unclear. Synaptotagmin-1 functions as a Ca{sup 2+} sensor in neurotransmitter release at central nervous system synapses, but synaptotagmin-7 does not, and yet both isoforms act as Ca{sup 2+} sensors in chromaffin cells. To shed light into this apparent paradox, we have performed rescue experiments in neurons from synaptotagmin-1 knockout mice using a chimera that contains the synaptotagmin-1 sequence with its C{sub 2}B domain replaced by the synaptotagmin-7 C{sub 2}B domain (Syt1/7). Rescue was not achieved either with the WT Syt1/7 chimera or with nine mutants where residues that are distinct in synaptotagmin-7 were restored to those present in synaptotagmin-1. To investigate whether these results arise because of unique conformational features of the synaptotagmin-7 C{sub 2}B domain, we determined its crystal structure at 1.44 {angstrom} resolution. The synaptotagmin-7 C{sub 2}B domain structure is very similar to that of the synaptotagmin-1 C{sub 2}B domain and contains three Ca{sup 2+}-binding sites. Two of the Ca{sup 2+}-binding sites of the synaptotagmin-7 C{sub 2}B domain are also present in the synaptotagmin-1 C{sub 2}B domain and have analogous ligands to those determined for the latter by NMR spectroscopy, suggesting that a discrepancy observed in a crystal structure of the synaptotagmin-1 C{sub 2}B domain arose from crystal contacts. Overall, our results suggest that functional differentiation in synaptotagmins arises in part from subtle sequence changes that yield dramatic functional differences.

Xue, Mingshan; Craig, Timothy K.; Shin, Ok-Ho; Li, Liyi; Brautigam, Chad A.; Tomchick, Diana R.; Südhof, Thomas C.; Rosenmund, Christian; Rizo, Josep (Baylor); (UTSMC); (Texas)

2012-01-20

462

Comparative morphology of the accessory olfactory bulb in bats.  

PubMed Central

Bouin-perfused brains of 148 bats (76 species, 48 genera, 8 families) were examined in serial sections for the presence of an accessory olfactory bulb. A moderate to well developed AOB was identified in 26 species. However, absence of an AOB in a particular species does not preclude its presence in some other species of that genus. Descriptions and measurements of the AOBs of each species are reported. The unmyelinated vomeronasal nerve enters the bulb medially and posteriorly. The glomeruli, variable in diameter, appear better circumscribed than previously described. Mitral cells often form thick layers, up to five cells deep, which sometimes reach the dorsolateral surface of the bulb formation. Both external and internal plexiform layers are thin. The latter, however is seen only in a few species. The internal granular layer, reaching the ventricular ependyma in some species, is a prominent component of the bulb. The pars dorsalis of the lateral olfactory tract usually courses between the mitral and internal granular layers. The chiropteran AOB does not differ in significant detail from that of insectivores, primates and other mammals. The occurrence of a functional vomeronasal system in the frugivorous, nectarivorous, and sanguivorous Phyllosotomatidae points to a primary functional role of this system in feeding strategy, at least in bats. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 PMID:7400042

Frahm, H D; Bhatnagar, K P

1980-01-01

463

21 CFR 874.4720 - Mediastinoscope and accessories.  

Code of Federal Regulations, 2010 CFR

...4720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4720 Mediastinoscope and accessories. (a)...

2010-04-01

464

21 CFR 874.4720 - Mediastinoscope and accessories.  

Code of Federal Regulations, 2011 CFR

...4720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4720 Mediastinoscope and accessories. (a)...

2011-04-01

465

21 CFR 874.4720 - Mediastinoscope and accessories.  

Code of Federal Regulations, 2013 CFR

...4720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4720 Mediastinoscope and accessories. (a)...

2013-04-01

466

21 CFR 874.4720 - Mediastinoscope and accessories.  

Code of Federal Regulations, 2012 CFR

...4720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4720 Mediastinoscope and accessories. (a)...

2012-04-01

467

21 CFR 874.4720 - Mediastinoscope and accessories.  

Code of Federal Regulations, 2014 CFR

...4720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4720 Mediastinoscope and accessories. (a)...

2014-04-01

468

26 CFR 48.4161(a)-3 - Parts and accessories.  

Code of Federal Regulations, 2010 CFR

... Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) MISCELLANEOUS EXCISE TAXES MANUFACTURERS AND RETAILERS EXCISE TAXES Sporting Goods § 48.4161(a)-3 Parts and accessories. (a) In general. The tax attaches with respect to parts...

2010-04-01

469

21 CFR 884.2700 - Intrauterine pressure monitor and accessories.  

Code of Federal Regulations, 2010 CFR

...Gynecological 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 fluid...

2010-04-01

470

What next for accessory dwellings? : getting from bylaws to buildings  

E-print Network

Accessory dwellings-secondary, self-contained housing units on the same property as a primary residence, either attached to or detached from the main dwelling, and subordinate in size, location and appearance-are recognized ...

Stege, Elinor Hope

2009-01-01

471

21 CFR 884.4100 - Endoscopic electrocautery and accessories.  

Code of Federal Regulations, 2012 CFR

...Sterility Review Guidance 2/12/90 (K-90),” and (iii) “Guidance (‘Guidelines’) for Evaluation of Laproscopic Bipolar and Thermal Coagulators (and Accessories),” (2) International Electrotechnical Commission's IEC 60601-1-AM2...

2012-04-01

472

21 CFR 884.4100 - Endoscopic electrocautery and accessories.  

Code of Federal Regulations, 2013 CFR

...Sterility Review Guidance 2/12/90 (K-90),” and (iii) “Guidance (‘Guidelines’) for Evaluation of Laproscopic Bipolar and Thermal Coagulators (and Accessories),” (2) International Electrotechnical Commission's IEC 60601-1-AM2...

2013-04-01

473

21 CFR 884.4100 - Endoscopic electrocautery and accessories.  

Code of Federal Regulations, 2014 CFR

...Sterility Review Guidance 2/12/90 (K-90),” and (iii) “Guidance (‘Guidelines’) for Evaluation of Laproscopic Bipolar and Thermal Coagulators (and Accessories),” (2) International Electrotechnical Commission's IEC 60601-1-AM2...

2014-04-01

474

21 CFR 884.4100 - Endoscopic electrocautery and accessories.  

Code of Federal Regulations, 2010 CFR

...Sterility Review Guidance 2/12/90 (K-90),” and (iii) “Guidance (‘Guidelines’) for Evaluation of Laproscopic Bipolar and Thermal Coagulators (and Accessories),” (2) International Electrotechnical Commission's IEC 60601-1-AM2...

2010-04-01

475

21 CFR 884.4100 - Endoscopic electrocautery and accessories.  

Code of Federal Regulations, 2011 CFR

...Sterility Review Guidance 2/12/90 (K-90),” and (iii) “Guidance (‘Guidelines’) for Evaluation of Laproscopic Bipolar and Thermal Coagulators (and Accessories),” (2) International Electrotechnical Commission's IEC 60601-1-AM2...

2011-04-01

476

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

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. Dominican Republic-Central America-United States Free Trade Agreement Rules of Origin § 10.600 Accessories, spare parts, or tools. (a)...

2010-04-01

477

21 CFR 876.5250 - Urine collector and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5250 Urine collector and accessories. (a) Identification. A...

2013-04-01

478

21 CFR 876.4890 - Urological table and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4890 Urological table and accessories. (a) Identification. A...

2010-04-01

479

21 CFR 876.5900 - Ostomy pouch and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5900 Ostomy pouch and accessories. (a) Identification. An...

2013-04-01

480

21 CFR 876.5250 - Urine collector and accessories.  

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5250 Urine collector and accessories. (a) Identification. A...

2014-04-01

481

21 CFR 876.4890 - Urological table and accessories.  

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4890 Urological table and accessories. (a) Identification. A...

2014-04-01

482

21 CFR 876.5900 - Ostomy pouch and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5900 Ostomy pouch and accessories. (a) Identification. An...

2010-04-01

483

21 CFR 876.5010 - Biliary catheter and accessories.  

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5010 Biliary catheter and accessories. (a) Identification. A...

2014-04-01

484

21 CFR 876.5250 - Urine collector and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5250 Urine collector and accessories. (a) Identification. A...

2010-04-01

485

21 CFR 876.5010 - Biliary catheter and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5010 Biliary catheter and accessories. (a) Identification. A...

2010-04-01

486

21 CFR 876.5010 - Biliary catheter and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5010 Biliary catheter and accessories. (a) Identification. A...

2013-04-01

487

21 CFR 876.4890 - Urological table and accessories.  

Code of Federal Regulations, 2011 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4890 Urological table and accessories. (a) Identification. A...

2011-04-01

488

21 CFR 876.5250 - Urine collector and accessories.  

Code of Federal Regulations, 2012 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5250 Urine collector and accessories. (a) Identification. A...

2012-04-01

489

21 CFR 876.5900 - Ostomy pouch and accessories.  

Code of Federal Regulations, 2012 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5900 Ostomy pouch and accessories. (a) Identification. An...

2012-04-01

490

21 CFR 876.4890 - Urological table and accessories.  

Code of Federal Regulations, 2012 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4890 Urological table and accessories. (a) Identification. A...

2012-04-01

491

21 CFR 876.5900 - Ostomy pouch and accessories.  

Code of Federal Regulations, 2011 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5900 Ostomy pouch and accessories. (a) Identification. An...

2011-04-01

492

21 CFR 876.5900 - Ostomy pouch and accessories.  

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5900 Ostomy pouch and accessories. (a) Identification. An...

2014-04-01

493

21 CFR 876.4890 - Urological table and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4890 Urological table and accessories. (a) Identification. A...

2013-04-01

494

21 CFR 876.5540 - Blood access device and accessories.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5540 Blood access device and accessories. (a) Identification....

2013-04-01

495

21 CFR 876.5250 - Urine collector and accessories.  

Code of Federal Regulations, 2011 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5250 Urine collector and accessories. (a) Identification. A...

2011-04-01

496

21 CFR 876.5540 - Blood access device and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5540 Blood access device and accessories. (a) Identification....

2010-04-01

497

21 CFR 878.1800 - Speculum and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Diagnostic Devices § 878.1800 Speculum and accessories. (a) Identification. A...

2010-04-01

498

21 CFR 878.4160 - Surgical camera and accessories.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4160 Surgical camera and accessories. (a) Identification. A...

2010-04-01

499

19 CFR 10.1020 - Accessories, spare parts, or tools.  

Code of Federal Regulations, 2014 CFR

...HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Korea Free Trade Agreement Rules of Origin § 10.1020 Accessories, spare parts, or tools. (a) General....

2014-04-01

500

21 CFR 872.3980 - Endosseous dental implant accessories.  

Code of Federal Regulations, 2013 CFR

... MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3980 Endosseous...abutments, aid in the fabrication of dental prosthetics, and be used as an accessory with...pieces used for fabrication of dental prosthetics, and trial abutments. (b)...

2013-04-01