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Sample records for aav inverted terminal

  1. Deletion of the B-B' and C-C' regions of inverted terminal repeats reduces rAAV productivity but increases transgene expression.

    Science.gov (United States)

    Zhou, Qingzhang; Tian, Wenhong; Liu, Chunguo; Lian, Zhonghui; Dong, Xiaoyan; Wu, Xiaobing

    2017-07-14

    Inverted terminal repeats (ITRs) of the adeno-associated virus (AAV) are essential for rescue, replication, packaging, and integration of the viral genome. While ITR mutations have been identified in previous reports, we designed a new truncated ITR lacking the B-B' and C-C' regions named as ITRΔBC and investigated its effects on viral genome replication, packaging, and expression of recombinant AAV (rAAV). The packaging ability was compared between ITRΔBC rAAV and wild-type (wt) ITR rAAV. Our results showed the productivity of ITRΔBC rAAV was reduced 4-fold, which is consistent with the 8-fold decrease in the replication of viral genomic DNA of ITRΔBC rAAV compared with wt ITR rAAV. Surprisingly, transgene expression was significantly higher for ITRΔBC rAAV. A preliminary exploration of the underlying mechanisms was carried out by inhibiting and degrading the ataxia telangiectasia mutated (ATM) protein and the Mre11 complex (MRN), respectively, since the rAAV expression was inhibited by the ATM and/or MRN through cis interaction or binding with wt ITRs. We demonstrated that the inhibitory effects were weakened on ITRΔBC rAAV expression. This study suggests deletion in ITR can affect the transgene expression of AAV, which provides a new way to improve the AAV expression through ITRs modification.

  2. Strategies to generate high-titer, high-potency recombinant AAV3 serotype vectors

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    Chen Ling

    2016-01-01

    Full Text Available Although recombinant adeno-associated virus serotype 3 (AAV3 vectors were largely ignored previously, owing to their poor transduction efficiency in most cells and tissues examined, our initial observation of the selective tropism of AAV3 serotype vectors for human liver cancer cell lines and primary human hepatocytes has led to renewed interest in this serotype. AAV3 vectors and their variants have recently proven to be extremely efficient in targeting human and nonhuman primate hepatocytes in vitro as well as in vivo. In the present studies, we wished to evaluate the relative contributions of the cis-acting inverted terminal repeats (ITRs from AAV3 (ITR3, as well as the trans-acting Rep proteins from AAV3 (Rep3 in the AAV3 vector production and transduction. To this end, we utilized two helper plasmids: pAAVr2c3, which carries rep2 and cap3 genes, and pAAVr3c3, which carries rep3 and cap3 genes. The combined use of AAV3 ITRs, AAV3 Rep proteins, and AAV3 capsids led to the production of recombinant vectors, AAV3-Rep3/ITR3, with up to approximately two to fourfold higher titers than AAV3-Rep2/ITR2 vectors produced using AAV2 ITRs, AAV2 Rep proteins, and AAV3 capsids. We also observed that the transduction efficiency of Rep3/ITR3 AAV3 vectors was approximately fourfold higher than that of Rep2/ITR2 AAV3 vectors in human hepatocellular carcinoma cell lines in vitro. The transduction efficiency of Rep3/ITR3 vectors was increased by ∼10-fold, when AAV3 capsids containing mutations in two surface-exposed residues (serine 663 and threonine 492 were used to generate a S663V+T492V double-mutant AAV3 vector. The Rep3/ITR3 AAV3 vectors also transduced human liver tumors in vivo approximately twofold more efficiently than those generated with Rep2/ITR2. Our data suggest that the transduction efficiency of AAV3 vectors can be significantly improved both using homologous Rep proteins and ITRs as well as by capsid optimization. Thus, the combined use of

  3. High-performance inkjet-printed four-terminal microelectromechanical relays and inverters.

    Science.gov (United States)

    Chung, Seungjun; Ul Karim, Muhammed Ahosan; Kwon, Hyuk-Jun; Subramanian, Vivek

    2015-05-13

    We report the first demonstration of inkjet-printed 4-terminal microelectromechanical (MEM) relays and inverters with hyper-abrupt switching that exhibit excellent electrical and mechanical characteristics. This first implementation of a printed 4-terminal device is critically important, since it allows for the realization of full complementary logic functions. The floated fourth terminal (body electrode), which allows the gate switching voltage to be adjusted, is bonded to movable channel beams via a printed epoxy layer in a planar structure, which can move downward together via the electrostatic force between the gate electrodes and body such that the channel can also actuate downward and touch the drain electrode. Because the body, channel, and drain electrodes are completely electrically separated, no detectable leakage or electrical interference between the electrodes is observed. The printed MEM relay exhibited an on-state resistance of only 3.48 Ω, immeasurable off-state leakage, subthreshold swing inverter exhibits abrupt transitions between on/off states. The operation of the printed 4-terminal MEM relay was also verified against the results of a 3-dimensional (3D) finite element simulation.

  4. Evaluating Efficiencies of Dual AAV Approaches for Retinal Targeting

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    Livia S. Carvalho

    2017-09-01

    Full Text Available Retinal gene therapy has come a long way in the last few decades and the development and improvement of new gene delivery technologies has been exponential. The recent promising results from the first clinical trials for inherited retinal degeneration due to mutations in RPE65 have provided a major breakthrough in the field and have helped cement the use of recombinant adeno-associated viruses (AAV as the major tool for retinal gene supplementation. One of the key problems of AAV however, is its limited capacity for packaging genomic information to a maximum of around 4.8 kb. Previous studies have demonstrated that homologous recombination and/or inverted terminal repeat (ITR mediated concatemerization of two overlapping AAV vectors can partially overcome the size limitation and help deliver larger transgenes. The aim of this study was to investigate and compare the use of different AAV dual-vector approaches in the mouse retina using a systematic approach comparing efficiencies in vitro and in vivo using a unique oversized reporter construct. We show that the hybrid approach relying on vector genome concatemerization by highly recombinogenic sequences and ITRs sequence overlap offers the best levels of reconstitution both in vitro and in vivo compared to trans-splicing and overlap strategies. Our data also demonstrate that dose and vector serotype do not affect reconstitution efficiency but a discrepancy between mRNA and protein expression data suggests a bottleneck affecting translation.

  5. Reversal of blindness in animal models of leber congenital amaurosis using optimized AAV2-mediated gene transfer.

    Science.gov (United States)

    Bennicelli, Jeannette; Wright, John Fraser; Komaromy, Andras; Jacobs, Jonathan B; Hauck, Bernd; Zelenaia, Olga; Mingozzi, Federico; Hui, Daniel; Chung, Daniel; Rex, Tonia S; Wei, Zhangyong; Qu, Guang; Zhou, Shangzhen; Zeiss, Caroline; Arruda, Valder R; Acland, Gregory M; Dell'Osso, Lou F; High, Katherine A; Maguire, Albert M; Bennett, Jean

    2008-03-01

    We evaluated the safety and efficacy of an optimized adeno-associated virus (AAV; AAV2.RPE65) in animal models of the RPE65 form of Leber congenital amaurosis (LCA). Protein expression was optimized by addition of a modified Kozak sequence at the translational start site of hRPE65. Modifications in AAV production and delivery included use of a long stuffer sequence to prevent reverse packaging from the AAV inverted-terminal repeats, and co-injection with a surfactant. The latter allows consistent and predictable delivery of a given dose of vector. We observed improved electroretinograms (ERGs) and visual acuity in Rpe65 mutant mice. This has not been reported previously using AAV2 vectors. Subretinal delivery of 8.25 x 10(10) vector genomes in affected dogs was well tolerated both locally and systemically, and treated animals showed improved visual behavior and pupillary responses, and reduced nystagmus within 2 weeks of injection. ERG responses confirmed the reversal of visual deficit. Immunohistochemistry confirmed transduction of retinal pigment epithelium cells and there was minimal toxicity to the retina as judged by histopathologic analysis. The data demonstrate that AAV2.RPE65 delivers the RPE65 transgene efficiently and quickly to the appropriate target cells in vivo in animal models. This vector holds great promise for treatment of LCA due to RPE65 mutations.

  6. A Compact MIMO Antenna with Inverted C-Shaped Ground Branches for Mobile Terminals

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    Zixian Yang

    2016-01-01

    Full Text Available A compact printed MIMO antenna for mobile terminals is presented. With two planar antenna elements, the −6 dB impedance bandwidth of 2.32 GHz (1.48–3.8 GHz is obtained, which covers GSM 1800/1900, UMTS, WLAN, Wimax, S-band, and most of LTE bands. Each antenna element with a small occupation of 15 × 20 mm2 consists of a driven strip and a shorted strip. Two inverted C-shaped ground branches are introduced between two elements to improve the isolation. The simulated results are studied and the measured results show that high isolation of more than 18 dB at the entire operating band is achieved. Meanwhile, the impedance performance is also improved by adding the branches. Furthermore, the measured radiation performances and envelope correlation coefficient also demonstrate that the proposed antenna could be a good candidate for mobile terminals.

  7. Practical utilization of recombinant AAV vector reference standards: focus on vector genomes titration by free ITR qPCR

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    Susan D'Costa

    2016-01-01

    Full Text Available Clinical trials using recombinant adeno-associated virus (rAAV vectors have demonstrated efficacy and a good safety profile. Although the field is advancing quickly, vector analytics and harmonization of dosage units are still a limitation for commercialization. AAV reference standard materials (RSMs can help ensure product safety by controlling the consistency of assays used to characterize rAAV stocks. The most widely utilized unit of vector dosing is based on the encapsidated vector genome. Quantitative polymerase chain reaction (qPCR is now the most common method to titer vector genomes (vg; however, significant inter- and intralaboratory variations have been documented using this technique. Here, RSMs and rAAV stocks were titered on the basis of an inverted terminal repeats (ITRs sequence-specific qPCR and we found an artificial increase in vg titers using a widely utilized approach. The PCR error was introduced by using single-cut linearized plasmid as the standard curve. This bias was eliminated using plasmid standards linearized just outside the ITR region on each end to facilitate the melting of the palindromic ITR sequences during PCR. This new “Free-ITR” qPCR delivers vg titers that are consistent with titers obtained with transgene-specific qPCR and could be used to normalize in-house product-specific AAV vector standards and controls to the rAAV RSMs. The free-ITR method, including well-characterized controls, will help to calibrate doses to compare preclinical and clinical data in the field.

  8. All-Graphene Three-Terminal-Junction Field-Effect Devices as Rectifiers and Inverters.

    Science.gov (United States)

    Kim, Wonjae; Li, Changfeng; Chekurov, Nikolai; Arpiainen, Sanna; Akinwande, Deji; Lipsanen, Harri; Riikonen, Juha

    2015-06-23

    We present prominent tunable and switchable room-temperature rectification performed at 100 kHz ac input utilizing micrometer-scale three-terminal junction field-effect devices. Monolayer CVD graphene is used as both a channel and a gate electrode to achieve all-graphene thin-film structure. Instead of ballistic theory, we explain the rectification characteristics through an electric-field capacitive model based on self-gating in the high source-drain bias regime. Previously, nanoscale graphene three-terminal junctions with the ballistic (or quasi-ballistic) operation have shown rectifications with relatively low efficiency. Compared to strict nanoscale requirements of ballistic devices, diffusive operation gives more freedom in design and fabrication, which we have exploited in the cascading device architecture. This is a significant step for all-graphene thin-film devices for integrated monolithic graphene circuits.

  9. AAVS1-Targeted Plasmid Integration in AAV Producer Cell Lines.

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    Luo, Yuxia; Frederick, Amy; Martin, John M; Scaria, Abraham; Cheng, Seng H; Armentano, Donna; Wadsworth, Samuel C; Vincent, Karen A

    2017-06-01

    Adeno-associated virus (AAV) producer cell lines are created via transfection of HeLaS3 cells with a single plasmid containing three components (the vector sequence, the AAV rep and cap genes, and a selectable marker gene). As this plasmid contains both the cis (Rep binding sites) and trans (Rep protein encoded by the rep gene) elements required for site-specific integration, it was predicted that plasmid integration might occur within the AAVS1 locus on human chromosome 19 (chr19). The objective of this study was to investigate whether integration in AAVS1 might be correlated with vector yield. Plasmid integration sites within several independent cell lines were assessed via Southern, fluorescence in situ hybridization (FISH) and PCR analyses. In the Southern analyses, the presence of fragments detected by both rep- and AAVS1-specific probes suggested that for several mid- and high-producing lines, plasmid DNA had integrated into the AAVS1 locus. Analysis with puroR and AAVS1-specific probes suggested that integration in AAVS1 was a more widespread phenomenon. High-producing AAV2-secreted alkaline phosphatase (SEAP) lines (masterwell 82 [MW82] and MW278) were evaluated via FISH using probes specific for the plasmid, AAVS1, and a chr19 marker. FISH analysis detected two plasmid integration sites in MW278 (neither in AAVS1), while a total of three sites were identified in MW82 (two in AAVS1). An inverse PCR assay confirmed integration within AAVS1 for several mid- and high-producing lines. In summary, the FISH, Southern, and PCR data provide evidence of site-specific integration of the plasmid within AAVS1 in several AAV producer cell lines. The data also suggest that integration in AAVS1 is a general phenomenon that is not necessarily restricted to high producers. The results also suggest that plasmid integration within the AAVS1 locus is not an absolute requirement for a high vector yield.

  10. Humoral immune response to AAV

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    Roberto eCalcedo

    2013-10-01

    Full Text Available Adeno-associated virus (AAV is a member of the family parvoviridae that has been widely used as a vector for gene therapy because of its safety profile, its ability to transduce both dividing and non-dividing cells, and its low immunogenicity. AAV has been detected in many different tissues of several animal species but has not been associated with any disease. As a result of natural infections, antibodies to AAV can be found in many animals including humans. It has been shown that pre-existing AAV antibodies can modulate the safety and efficacy of AAV vector-mediated gene therapy by blocking vector transduction or by redirecting distribution of AAV vectors to tissues other than the target organ. This review will summarize antibody responses against natural AAV infections, as well as AAV gene therapy vectors and their impact in the clinical development of AAV vectors for gene therapy. We will also review and discuss the various methods used for AAV antibody detection and strategies to overcome neutralizing antibodies in AAV-mediated gene therapy.

  11. An Intrabody Drug (rAAV6-INT41 Reduces the Binding of N-Terminal Huntingtin Fragment(s to DNA to Basal Levels in PC12 Cells and Delays Cognitive Loss in the R6/2 Animal Model

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    I. Alexandra Amaro

    2016-01-01

    Full Text Available Huntington’s disease (HD is a fatal progressive disease linked to expansion of glutamine repeats in the huntingtin protein and characterized by the progressive loss of cognitive and motor function. We show that expression of a mutant human huntingtin exon-1-GFP fusion construct results in nonspecific gene dysregulation that is significantly reduced by 50% due to coexpression of INT41, an intrabody specific for the proline-rich region of the huntingtin protein. Using stable PC12 cell lines expressing either inducible human mutant huntingtin (mHtt, Q73 or normal huntingtin (nHtt, Q23, we investigated the effect of rAAV6-INT41, an adeno-associated virus vector with the INT41 coding sequence, on the subcellular distribution of Htt. Compartmental fractionation 8 days after induction of Htt showed a 6-fold increased association of a dominate N-terminal mHtt fragment with DNA compared to N-terminal nHtt. Transduction with rAAV6-INT41 reduced DNA binding of N-terminal mHtt 6.5-fold in the nucleus and reduced nuclear translocation of the detected fragments. Subsequently, when rAAV6-INT41 is delivered to the striatum in the R6/2 mouse model, treated female mice exhibited executive function statistically indistinguishable from wild type, accompanied by reductions in Htt aggregates in the striatum, suggesting that rAAV6-INT41 is promising as a gene therapy for Huntington’s disease.

  12. Prenatal detection of a de novo terminal inverted duplication 4p in a fetus with the Wolf-Hirschhorn syndrome phenotype.

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    Beaujard, M-P; Jouannic, J-M; Bessières, B; Borie, C; Martin-Luis, I; Fallet-Bianco, C; Portnoï, M-F

    2005-06-01

    To present the prenatal diagnosis of a de novo terminal inversion duplication of the short arm of chromosome 4 and a review of the literature. An amniocentesis for chromosome analysis was performed at 33 weeks' gestation because ultrasound examination showed a female fetus with multiple abnormalities consisting of severe intrauterine growth retardation, microcephaly, a cleft lip and renal hypoplasia. Cytogenetic analysis and FISH studies of the cultured amniocytes revealed a de novo terminal inversion duplication of the short arm of chromosome 4 characterized by a duplication of 4p14-p16.1 chromosome region concomitant with a terminal deletion 4p16.1-pter. The karyotype was thus: 46,XX, inv dup del (4)(:p14-->p16.1::p16.1-->qter). The parents opted to terminate the pregnancy. Fetopathological examination showed dysmorphic features and abnormalities consistent with a Wolf-Hirschhorn syndrome (WHS) diagnosis, clinical manifestations of partial 4p trisomy being mild. Although relatively rare, inverted duplications have been reported repeatedly in an increasing number of chromosomes. Only two previous cases with de novo inv dup del (4p) and one with tandem dup 4p have been reported, all of them associated with a 4pter deletion. We report the first case diagnosed prenatally. Breakpoints are variable, resulting in different abnormal phenotype. In our case, clinical manifestations resulted in a WHS phenotype.

  13. Analysis of the genome sequence of the pathogenic Muscovy duck parvovirus strain YY reveals a 14-nucleotide-pair deletion in the inverted terminal repeats.

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    Wang, Jianye; Huang, Yu; Zhou, Mingxu; Zhu, Guoqiang

    2016-09-01

    Genomic information about Muscovy duck parvovirus is still limited. In this study, the genome of the pathogenic MDPV strain YY was sequenced. The full-length genome of YY is 5075 nucleotides (nt) long, 57 nt shorter than that of strain FM. Sequence alignment indicates that the 5' and 3' inverted terminal repeats (ITR) of strain YY contain a 14-nucleotide-pair deletion in the stem of the palindromic hairpin structure in comparison to strain FM and FZ91-30. The deleted region contains one "E-box" site and one repeated motif with the sequence "TTCCGGT" or "ACCGGAA". Phylogenetic trees constructed based the protein coding genes concordantly showed that YY, together with nine other MDPV isolates from various places, clustered in a separate branch, distinct from the branch formed by goose parvovirus (GPV) strains. These results demonstrate that, despite the distinctive deletion, the YY strain still belongs to the classical MDPV group. Moreover, the deletion of ITR may contribute to the genome evolution of MDPV under immunization pressure.

  14. Synthetic AAV/CRISPR vectors for blocking HIV-1 expression in persistently infected astrocytes.

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    Kunze, Christine; Börner, Kathleen; Kienle, Eike; Orschmann, Tanja; Rusha, Ejona; Schneider, Martha; Radivojkov-Blagojevic, Milena; Drukker, Micha; Desbordes, Sabrina; Grimm, Dirk; Brack-Werner, Ruth

    2018-02-01

    Astrocytes, the most abundant cells in the mammalian brain, perform key functions and are involved in several neurodegenerative diseases. The human immunodeficiency virus (HIV) can persist in astrocytes, contributing to the HIV burden and neurological dysfunctions in infected individuals. While a comprehensive approach to HIV cure must include the targeting of HIV-1 in astrocytes, dedicated tools for this purpose are still lacking. Here we report a novel Adeno-associated virus-based vector (AAV9P1) with a synthetic surface peptide for transduction of astrocytes. Analysis of AAV9P1 transduction efficiencies with single brain cell populations, including primary human brain cells, as well as human brain organoids demonstrated that AAV9P1 targeted terminally differentiated human astrocytes much more efficiently than neurons. We then investigated whether AAV9P1 can be used to deliver HIV-inhibitory genes to astrocytes. To this end we generated AAV9P1 vectors containing genes for HIV-1 proviral editing by CRISPR/Cas9. Latently HIV-1 infected astrocytes transduced with these vectors showed significantly diminished reactivation of proviruses, compared with untransduced cultures. Sequence analysis identified mutations/deletions in key HIV-1 transcriptional control regions. We conclude that AAV9P1 is a promising tool for gene delivery to astrocytes and may facilitate inactivation/destruction of persisting HIV-1 proviruses in astrocyte reservoirs. © 2017 Wiley Periodicals, Inc.

  15. Embedded EZ-Source Inverters

    DEFF Research Database (Denmark)

    Chiang Loh, Poh; Gao, Feng; Blaabjerg, Frede

    2010-01-01

    Z-source inverters are recent topological options proposed for buck–boost energy conversion with a number of possible voltage- and current-type circuitries already reported in the literature. Comparing them, a common feature noted is their inclusion of an LC impedance network, placed between the dc...... input source and inverter bridge. This impedance network allows the output end of a voltage-type Z-source inverter to be shorted for voltage boosting without causing a large current flow and the terminal current of a current-type inverter to be interrupted for current boosting without introducing...... overvoltage oscillations to the system. Therefore, Z-source inverters are, in effect, safer and less complex and can be implemented using only passive elements with no additional active semiconductor needed. Believing in the prospects of Z-source inverters, this paper contributes by introducing a new family...

  16. Embedded EZ-Source Inverters

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Loh, Poh Chiang; Gao, F.

    2008-01-01

    Z-source inverters are recent topological options proposed for buck-boost energy conversion with a number of possible voltage and current-type circuitries already reported in the literature. Comparing them, a common feature noted is their inclusion of a LC impedance network, placed between the dc...... input source and inverter bridge. This impedance network allows the output end of a voltage-type Z-source inverter to be shorted for voltage-boosting without causing a large current flow, and the terminal current of a current-type inverter to be interrupted for current boosting without introducing over......-voltage oscillations to the system. Therefore, Z-source inverters are in effect safer and less complex, and can be implemented using only passive elements with no additional active semiconductor needed. Believing in the prospects of Z-source inverters, this paper contributes by introducing a new family of embedded EZ-source...

  17. The ANCA Vasculitis Questionnaire (AAV-PRO©)

    Science.gov (United States)

    2017-05-01

    Eosinophilic Granulomatosis With Polyangiitis (Churg-Strauss) (EGPA); Churg-Strauss Syndrome (CSS); Granulomatosis With Polyangiitis (Wegener's) (GPA); Wegener Granulomatosis (WG); Microscopic Polyangiitis (MPA); ANCA-Associated Vasculitis (AAV); Vasculitis

  18. AAV VECTORS VACCINES AGAINST INFECTIOUS DISEASES

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    Karen eNieto

    2014-01-01

    Full Text Available Since their discovery as a tool for gene transfer, vectors derived from the Adeno-Associated Virus (AAV have been used for gene therapy applications and attracted scientist to this field for their exceptional properties of efficiency of in vivo gene transfer and the level and duration of transgene expression. For many years, AAVs have been considered as low immunogenic vectors due to their ability to induce long term expression of non-self-proteins in contrast to what has been observed with other viral vectors, such as adenovirus (Ad, for which strong immune responses against the same transgene products were documented. The perceived low immunogenicity likely explains why the use of AAV vectors for vaccination was not seriously considered before the early 2000s. Indeed, while analyses conducted using a variety of transgenes and animal species slowly changed the vision of the immunological properties of AAVs, an increasing number of studies were also performed in the field of vaccination. Even if the comparison with other modes of vaccination was not systemically performed, the analyses conducted so far in the field of active immunotherapy strongly suggest that AAVs possess some interesting features to be used as tools to produce an efficient and sustained antibody (Ab response. In addition, recent studies also highlighted the potential of AAVs for passive immunotherapy. This review summarizes the main studies conducted to evaluate the potential of AAV vectors for vaccination against infectious agents and discusses their advantages and drawbacks. Altogether, the variety of studies conducted in this field contributes to the understanding of the immunological properties of this versatile virus and to the definition of its possible future applications.

  19. [Inverted nipples].

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    Saltvig, Iselin; Sjøstrand, Helle; Oldenburg, Mette Holmqvist; Matzen, Steen Henrik

    2016-10-17

    Inverted nipples is an anatomical variation which can be uni- or bilateral, congenital or acquired. The degree of inversion can vary from slight to severe. Treatment can be surgical or non-surgical and should depend on the degree of functional problems. Non-surgical treatment can be beneficial, does not risk affecting sensibility, spares the lactiferous ducts, and therefore does not risk any interference with breast-feeding. Surgical options should only be considered when non-surgical treatment is insufficient.

  20. Delivery of AAV2/9-microdystrophin genes incorporating helix 1 of the coiled-coil motif in the C-terminal domain of dystrophin improves muscle pathology and restores the level of α1-syntrophin and α-dystrobrevin in skeletal muscles of mdx mice.

    Science.gov (United States)

    Koo, Taeyoung; Malerba, Alberto; Athanasopoulos, Takis; Trollet, Capucine; Boldrin, Luisa; Ferry, Arnaud; Popplewell, Linda; Foster, Helen; Foster, Keith; Dickson, George

    2011-11-01

    Duchenne muscular dystrophy is a severe X-linked inherited muscle wasting disorder caused by mutations in the dystrophin gene. Adeno-associated virus (AAV) vectors have been extensively used to deliver genes efficiently for dystrophin expression in skeletal muscles. To overcome limited packaging capacity of AAV vectors (pathology of dystrophic mdx mice. However, the CT domain of dystrophin is thought to recruit part of the dystrophin-associated protein complex, which acts as a mediator of signaling between extracellular matrix and cytoskeleton in muscle fibers. In this study, we extended the ΔR4-23/ΔCT microdystrophin by incorporating helix 1 of the coiled-coil motif in the CT domain of dystrophin (MD2), which contains the α1-syntrophin and α-dystrobrevin binding sites. Intramuscular injection of AAV2/9 expressing CT domain-extended microdystrophin showed efficient dystrophin expression in tibialis anterior muscles of mdx mice. The presence of the CT domain of dystrophin in MD2 increased the recruitment of α1-syntrophin and α-dystrobrevin at the sarcolemma and significantly improved the muscle resistance to lengthening contraction-induced muscle damage in the mdx mice compared with MD1. These results suggest that the incorporation of helix 1 of the coiled-coil motif in the CT domain of dystrophin to the microdystrophins will substantially improve their efficiency in restoring muscle function in patients with Duchenne muscular dystrophy.

  1. A Transformer-less Single Phase Inverter For photovoltaic Systems

    DEFF Research Database (Denmark)

    Mostaan, Ali; Alizadeh, Ebrahim; Qu, Ying

    2017-01-01

    A single phase transformer-less inverter is introduced in this paper. The negative polarities of the input voltage and output terminal have common ground. Therefore, the leakage current problem that is common in PV systems is eliminated naturally. In addition, the proposed inverter has fewer...... components compared with its counterparts and only one switch conducts during the active states which enhance the inverter efficiency. The proposed inverter is analyzed in details and compared with some existing topologies. The performance of the proposed inverter is validated using the simulation results....

  2. Viral and Cellular Components of AAV2 Replication Compartments

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    Vogel, Rebecca; Seyffert, Michael; Pereira, Bruna de Andrade; Fraefel, Cornel

    2013-01-01

    Adeno-associated virus 2 (AAV2) is a helpervirus-dependent parvovirus with a bi-phasic life cycle comprising latency in absence and lytic replication in presence of a helpervirus, such as adenovirus (Ad) or herpes simplex virus type 1 (HSV-1). Helpervirus-supported AAV2 replication takes place in replication compartments (RCs) in the cell nucleus where virus DNA replication and transcription occur. RCs consist of a defined set of helper virus-, AAV2-, and cellular proteins. Here we compare the profile of cellular proteins recruited into AAV2 RCs or identified in Rep78-associated complexes when either Ad or HSV-1 is the helpervirus, and we discuss the potential roles of some of these proteins in AAV2 and helpervirus infection. PMID:24222808

  3. Mutational Analysis of the Adeno-Associated Virus Type 2 (AAV2) Capsid Gene and Construction of AAV2 Vectors with Altered Tropism

    Science.gov (United States)

    Wu, Pei; Xiao, Wu; Conlon, Thomas; Hughes, Jeffrey; Agbandje-McKenna, Mavis; Ferkol, Thomas; Flotte, Terence; Muzyczka, Nicholas

    2000-01-01

    insertions identified several other regions that were on the surface of the capsid. These included insertions at amino acids 1, 34, 138, 266, 447, 591, and 664. Positions 1 and 138 were the N termini of VP1 and VP2, respectively; position 34 was exclusively in VP1; the remaining surface positions were located in putative loop regions of VP3. The remaining mutants, most of them partially defective, were presumably defective in steps of viral entry that were not tested in the preliminary screening, including intracellular trafficking, viral uncoating, or coreceptor binding. Finally, in vitro experiments showed that insertion of the serpin receptor ligand in the N-terminal regions of VP1 or VP2 can change the tropism of AAV. Our results provide information on AAV capsid functional domains and are useful for future design of AAV vectors for targeting of specific tissues. PMID:10954565

  4. AAV capsid CD8+ T-cell epitopes are highly conserved across AAV serotypes

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    Daniel J Hui

    Full Text Available Adeno-associated virus (AAV has become one of the most promising vectors in gene transfer in the last 10 years with successful translation to clinical trials in humans and even market approval for a first gene therapy product in Europe. Administration to humans, however, revealed that adaptive immune responses against the vector capsid can present an obstacle to sustained transgene expression due to the activation and expansion of capsid-specific T cells. The limited number of peripheral blood mononuclear cells (PBMCs obtained from samples within clinical trials allows for little more than monitoring of T-cell responses. We were able to identify immunodominant major histocompatibility complex (MHC class I epitopes for common human leukocyte antigen (HLA types by using spleens isolated from subjects undergoing splenectomy for non-malignant indications as a source of large numbers of lymphocytes and restimulating them with single AAV capsid peptides in vitro. Further experiments confirmed that these epitopes are naturally processed and functionally relevant. The design of more effective and less immunogenic AAV vectors, and precise immune monitoring of vector-infused subjects, are facilitated by these findings.

  5. Electronic inverter assembly with an integral snubber capacitor

    Science.gov (United States)

    Singh, Brij N.; Schmit, Christopher J.

    2017-08-01

    A coaxial bus connector has a first end and a second end opposite the first end. The first end has a first positive terminal and a first negative terminal coupled to a primary direct current bus of a primary inverter. The second end has a second positive terminal and a second negative terminal coupled to the secondary direct current bus of a secondary inverter, wherein the coaxial bus connector comprises a dielectric material between a center conductor and a coaxial sleeve to form a snubber capacitor to absorb electrical energy or to absorb voltage spikes.

  6. Next Generation Inverter

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Zilai [General Motors LLC, Detroit, MI (United States); Gough, Charles [General Motors LLC, Detroit, MI (United States)

    2016-04-22

    The goal of this Cooperative Agreement was the development of a Next Generation Inverter for General Motors’ electrified vehicles, including battery electric vehicles, range extended electric vehicles, plug-in hybrid electric vehicles and hybrid electric vehicles. The inverter is a critical electronics component that converts battery power (DC) to and from the electric power for the motor (AC).

  7. Y-source inverter

    DEFF Research Database (Denmark)

    Siwakoti, Yam P.; Town, Graham; Loh, Poh Chiang

    2014-01-01

    This paper introduces a new 3-phase Y-source inverter whose gain is presently not matched by classical impedance-network-based inverters operating at the same duty ratio. The proposed network uses a tightly coupled transformer with three windings. By squeezing the shoot-through range while keeping...

  8. Modular inverter system

    Science.gov (United States)

    Ma, Mingyao; Hu, Haibing; Kutkut, Nasser; Batarseh, Issa; Shen, John; , Bkayrat, Raed

    2017-08-01

    A system connected to an AC power grid having an AC phase signal includes an inverter module including a first inverter coupled to a DC voltage, actuated based on the AC phase signal. The first inverter provides a first voltage signal having predetermined harmonic components. A second inverter includes second switch elements coupled to the DC voltage and actuated by a second set of control signals phase delayed with respect to the first control signals. A transformer module has first and second primary windings coupled to the first and second inverters. The transformer module further includes a secondary winding coupled to first primary winding, the second primary winding, and the AC power grid. The secondary winding is configured to provide a secondary output voltage to the AC power grid by combining the first voltage signal and the second voltage signal such that the predetermined harmonic components are substantially cancelled.

  9. Safety and Biodistribution Evaluation in CNGB3-Deficient Mice of rAAV2tYF-PR1.7-hCNGB3, a Recombinant AAV Vector for Treatment of Achromatopsia.

    Science.gov (United States)

    Ye, Guo-jie; Budzynski, Ewa; Sonnentag, Peter; Nork, T Michael; Miller, Paul E; McPherson, Leslie; Ver Hoeve, James N; Smith, Leia M; Arndt, Tara; Mandapati, Savitri; Robinson, Paulette M; Calcedo, Roberto; Knop, David R; Hauswirth, William W; Chulay, Jeffrey D

    2016-03-01

    Applied Genetic Technologies Corporation (AGTC) is developing rAAV2tYF-PR1.7-hCNGB3, a recombinant adeno-associated virus (rAAV) vector expressing the human CNGB3 gene, for treatment of achromatopsia, an inherited retinal disorder characterized by markedly reduced visual acuity, extreme light sensitivity, and absence of color discrimination. We report here results of a study evaluating safety and biodistribution of rAAV2tYF-PR1.7-hCNGB3 in CNGB3-deficient mice. Three groups of animals (n = 35 males and 35 females per group) received a subretinal injection in one eye of 1 μl containing either vehicle or rAAV2tYF-PR1.7-hCNGB3 at one of two dose concentrations (1 × 10(12) or 4.2 × 10(12) vg/ml) and were euthanized 4 or 13 weeks later. There were no test-article-related changes in clinical observations, body weights, food consumption, ocular examinations, clinical pathology parameters, organ weights, or macroscopic observations at necropsy. Cone-mediated electroretinography (ERG) responses were detected after vector administration in the treated eyes in 90% of animals in the higher dose group and 31% of animals in the lower dose group. Rod-mediated ERG responses were reduced in the treated eye for all groups, with the greatest reduction in males given the higher dose of vector, but returned to normal by the end of the study. Microscopic pathology results demonstrated minimal mononuclear cell infiltrates in the retina and vitreous of some animals at the interim euthanasia and in the vitreous of some animals at the terminal euthanasia. Serum anti-AAV antibodies developed in most vector-injected animals. No animals developed antibodies to hCNGB3. Biodistribution studies demonstrated high levels of vector DNA in vector-injected eyes but little or no vector DNA in nonocular tissue. These results support the use of rAAV2tYF-PR1.7-hCNGB3 in clinical studies in patients with achromatopsia caused by CNGB3 mutations.

  10. Widespread AAV1- and AAV2-mediated transgene expression in the nonhuman primate brain: implications for Huntington's disease

    Directory of Open Access Journals (Sweden)

    Piotr Hadaczek

    2016-01-01

    Full Text Available Huntington's disease (HD is caused by a toxic gain-of-function associated with the expression of the mutant huntingtin (htt protein. Therefore, the use of RNA interference to inhibit Htt expression could represent a disease-modifying therapy. The potential of two recombinant adeno-associated viral vectors (AAV, AAV1 and AAV2, to transduce the cortico-striatal tissues that are predominantly affected in HD was explored. Green fluorescent protein was used as a reporter in each vector to show that both serotypes were broadly distributed in medium spiny neurons in the striatum and cortico-striatal neurons after infusion into the putamen and caudate nucleus of nonhuman primates (NHP, with AAV1-directed expression being slightly more robust than AAV2-driven expression. This study suggests that both serotypes are capable of targeting neurons that degenerate in HD, and it sets the stage for the advanced preclinical evaluation of an RNAi-based therapy for this disease.

  11. Mapping the AAV capsid host antibody response towards the development of second generation gene delivery vectors

    Directory of Open Access Journals (Sweden)

    Yu-Shan eTseng

    2014-01-01

    Full Text Available The recombinant Adeno-associated virus (rAAV gene delivery system is entering a crucial and exciting phase with the promise of more than 20 years of intense research now realized in a number of successful human clinical trials. However, as a natural host to AAV infection, anti-AAV antibodies are prevalent in the human population. For example, ~70% of human sera samples are positive for AAV serotype 2 (AAV2. Furthermore, low levels of pre-existing neutralizing antibodies in the circulation are detrimental to the efficacy of corrective therapeutic AAV gene delivery. A key component to overcoming this obstacle is the identification of regions of the AAV capsid that participate in interactions with host immunity, especially neutralizing antibodies, to be modified for neutralization escape. Three main approaches have been utilized to map antigenic epitopes on AAV capsids. The first is directed evolution in which AAV variants are selected in the presence of monoclonal antibodies or pooled human sera. This results in AAV variants with mutations on important neutralizing epitopes. The second is epitope searching, achieved by peptide scanning, peptide insertion or site-directed mutagenesis. The third, a structure biology-based approach, utilizes cryo-electron microscopy and image reconstruction of AAV capsids complexed to fragment antibodies, which are generated from monoclonal antibodies, to directly visualize the epitopes. In this review, the contribution of these three approaches to the current knowledge of AAV epitopes and success in their use to create second generation vectors will be discussed.

  12. Multilevel DC link inverter

    Science.gov (United States)

    Su, Gui-Jia

    2003-06-10

    A multilevel DC link inverter and method for improving torque response and current regulation in permanent magnet motors and switched reluctance motors having a low inductance includes a plurality of voltage controlled cells connected in series for applying a resulting dc voltage comprised of one or more incremental dc voltages. The cells are provided with switches for increasing the resulting applied dc voltage as speed and back EMF increase, while limiting the voltage that is applied to the commutation switches to perform PWM or dc voltage stepping functions, so as to limit current ripple in the stator windings below an acceptable level, typically 5%. Several embodiments are disclosed including inverters using IGBT's, inverters using thyristors. All of the inverters are operable in both motoring and regenerating modes.

  13. Adeno-Associated Virus Vectors (AAV Expressing Phenylalanine Hydroxylase (PAH

    Directory of Open Access Journals (Sweden)

    Ayşegül Akbay Yarpuzlu

    2009-06-01

    Full Text Available Recent articles have appeared in the literature reporting use of adeno-associated virus vectors (AAV expressing phenylalanine hydroxylase in animal trials and suggesting its use in treatment of phenylketonuria (PKU as a form of gene therapy However, agents used in gene therapy to deliver genes are not site-specific and DNA is may be put in the wrong place, causing damage to the organism. The adverse immunogenicity of AAVs also needs to be reconsidered. This letter is written to discuss present unreadiness for Phase 1 clinical trials of gene therapy of PKU. Turk Jem 2009; 13: 18-9

  14. Reliable inverter systems

    Science.gov (United States)

    Nagano, S.

    1979-01-01

    Base driver with common-load-current feedback protects paralleled inverter systems from open or short circuits. Circuit eliminates total system oscillation that can occur in conventional inverters because of open circuit in primary transformer winding. Common feedback signal produced by functioning modules forces operating frequency of failed module to coincide with clock drive so module resumes normal operating frequency in spite of open circuit.

  15. The Rep78 gene product of adeno-associated virus (AAV) self-associates to form a hexameric complex in the presence of AAV ori sequences.

    Science.gov (United States)

    Smith, R H; Spano, A J; Kotin, R M

    1997-06-01

    The Rep78 and Rep68 proteins of adeno-associated virus (AAV) are replication initiator proteins that bind the viral replicative-form origin of replication, nick the origin in a site- and strand-specific fashion, and mediate vectorial unwinding of the DNA duplex via an ATP-dependent helicase activity, thus initiating a strand displacement mechanism of viral DNA replication. Genetic and biochemical studies have identified Rep mutants that demonstrate a trans-dominant negative phenotype in vitro and in vivo, suggesting the possibility that multimerization of Rep is essential for certain replicative functions. In this study, we have investigated the ability of the largest of the Rep proteins, Rep78, to self-associate in vitro and in vivo. Self-association of Rep78 in vivo was demonstrated through the use of a mammalian two-hybrid system. Rep-Rep protein interaction was confirmed in vitro through coimmunoprecipitation experiments with a bacterially expressed maltose-binding protein-Rep78 fusion protein in combination with [35S]methionine-labeled Rep78 synthesized in a coupled in vitro transcription-translation system. Mapping studies with N- and C-terminal truncation mutant forms of Rep indicate that amino acid sequences required for maximal self-association occur between residues 164 and 484. Site-directed mutagenesis identified two essential motifs within this 321-amino-acid region: (i) a putative alpha-helix bearing a 3,4-hydrophobic heptad repeat reminiscent of those found in coiled-coil domains and (ii) a previously recognized nucleoside triphosphate-binding motif. Deletion of either of these regions from the full-length polypeptide resulted in severe impairment of Rep-Rep interaction. In addition, gel filtration chromatography and protein cross-linking experiments indicated that Rep78 forms a hexameric complex in the presence of AAV ori sequences.

  16. On Stability of Voltage Source Inverters in Weak Grids

    DEFF Research Database (Denmark)

    Adib, Aswad; Mirafza, Behrooz; Wang, Xiongfei

    2018-01-01

    of circuit and control parameters on the stability of voltage source inverters are studied using a small-signal state-space model in the synchronously rotating dq-frame of reference. The full order state-space model developed in this work is directly extracted from Pulse-Width Modulation (PWM) switching......As the number of inverters increases in the power grid, the stability of grid-tied inverters becomes an important concern for the power industry. In particular, a weak grid can lead to voltage fluctuations at the inverter terminals and consequently cause inverter instability. In this paper, impacts...... pattern, and enables the stability analysis of concurrent variations in the three-phase circuit and control parameters. This paper demonstrates that the full-order model of a grid-tied PQ-controlled VSI can be significantly reduced to a second-order model, preserving the overall system stability in case...

  17. Small But Increasingly Mighty: Latest Advances in AAV Vector Research, Design, and Evolution.

    Science.gov (United States)

    Grimm, Dirk; Büning, Hildegard

    2017-11-01

    Recombinant gene delivery vectors derived from naturally occurring or genetically engineered adeno-associated viruses (AAV) have taken center stage in human gene therapy, fueled by rapidly accumulating and highly encouraging clinical data. Nonetheless, it has also become evident that the current generation of AAV vectors will require improvements in transduction potency, antibody evasion, and cell specificity in order to realize their full potential and to widen applicability in larger patient cohorts. Fortunately, in the recent past, the field has seen a flurry of exciting new developments that enhance our understanding of AAV vector biology, including virus-host interactions, and/or that expand our arsenal of technologies for AAV capsid design and evolution. This review highlights a collection of latest advances in these areas, which, in the authors' opinion, hold particular promise to propel the AAV vector field forward in the near future, especially when applied in combination. These include fundamental novel insights into the AAV life cycle, from an unexpected role of autophagy and interactions with other viruses to the (re-)discovery of a universal AAV receptor and the function of AAV-AAP for capsid assembly. Concurrently, recent successes in the rational design of next-generation synthetic AAV capsids are pointed out, exemplified by the structure-guided derivation of AAV mutants displaying robust in vivo immune evasion. Finally, a variety of new and innovative strategies for high-throughput generation and screening of AAV capsid libraries are briefly reviewed, including Cre recombinase-based selection, ancestral AAV capsid reconstruction, and DNA barcoding of AAV genomes. All of these examples showcase the present momentum in the AAV field and, together with work by many other academic or industrial entities, raise substantial optimism that the remaining hurdles for human gene therapy with AAV vectors will (soon) be overcome.

  18. Long-term correction of very long-chain acyl-coA dehydrogenase deficiency in mice using AAV9 gene therapy.

    Science.gov (United States)

    Keeler, Allison M; Conlon, Thomas; Walter, Glenn; Zeng, Huadong; Shaffer, Scott A; Dungtao, Fu; Erger, Kirsten; Cossette, Travis; Tang, Qiushi; Mueller, Christian; Flotte, Terence R

    2012-06-01

    Very long-chain acyl-coA dehydrogenase (VLCAD) is the rate-limiting step in mitochondrial fatty acid oxidation. VLCAD-deficient mice and patients clinical symptoms stem from not only an energy deficiency but also long-chain metabolite accumulations. VLCAD-deficient mice were treated systemically with 1 × 10(12) vector genomes of recombinant adeno-associated virus 9 (rAAV9)-VLCAD. Biochemical correction was observed in vector-treated mice beginning 2 weeks postinjection, as characterized by a significant drop in long-chain fatty acyl accumulates in whole blood after an overnight fast. Changes persisted through the termination point around 20 weeks postinjection. Magnetic resonance spectroscopy (MRS) and tandem mass spectrometry (MS/MS) revealed normalization of intramuscular lipids in treated animals. Correction was not observed in liver tissue extracts, but cardiac muscle extracts showed significant reduction of long-chain metabolites. Disease-specific phenotypes were characterized, including thermoregulation and maintenance of euglycemia after a fasting cold challenge. Internal body temperatures of untreated VLCAD(-/-) mice dropped below 20 °C and the mice became lethargic, requiring euthanasia. In contrast, all rAAV9-treated VLCAD(-/-) mice and the wild-type controls maintained body temperatures. rAAV9-treated VLCAD(-/-) mice maintained euglycemia, whereas untreated VLCAD(-/-) mice suffered hypoglycemia following a fasting cold challenge. These promising results suggest rAAV9 gene therapy as a potential treatment for VLCAD deficiency in humans.

  19. Development of rAAV2-CFTR: History of the First rAAV Vector Product to be Used in Humans.

    Science.gov (United States)

    Loring, Heather S; ElMallah, Mai K; Flotte, Terence R

    2016-04-01

    The first human gene therapy trials using recombinant adeno-associated virus (rAAV) vectors were performed in cystic fibrosis (CF) patients. Over 100 CF patients were enrolled in 5 separate trials of rAAV2-CFTR administration via nasal, endobronchial, maxillary sinus, and aerosol delivery. Recombinant AAV vectors were designed to deliver the CF transmembrane regulator (CFTR) gene and correct the basic CFTR defect by restoring chloride transport and reverting the upregulation of proinflammatory cytokines. However, vector DNA expression was limited in duration because of the low incidence of integration and natural airway epithelium turnover. In addition, repeated administration of AAV-CFTR vector resulted in a humoral immune response that prevented effective gene transfer from subsequent doses of vector. AAV serotype 2 was used in human trials before the comparison with other serotypes and determination that serotypes 1 and 5 not only possess higher tropism for the airway epithelium, but also are capable of bypassing the binding and trafficking processes-both were important hindrances to the effectiveness of rAAV2. Although rAAV-CFTR gene therapy does not appear likely to supplant newer small-molecule CFTR modulators in the near future, early work with rAAV-CFTR provided an important foundation for later use of rAAV in humans.

  20. Effective inhibition of specific gene by adenoassociated virus (AAV ...

    African Journals Online (AJOL)

    To perform functional tests on siRNA, which was expressed by the viral vector, recombinant AAVs, coding for siRNA against exogenous gene, EGFP, and endogenous gene, p53, were established and added into HEK293 cells, respectively. The results proved the expression of EGFP and p53 in cells were definitely ...

  1. Recurrent AAV2-related insertional mutagenesis in human hepatocellular carcinomas.

    Science.gov (United States)

    Nault, Jean-Charles; Datta, Shalini; Imbeaud, Sandrine; Franconi, Andrea; Mallet, Maxime; Couchy, Gabrielle; Letouzé, Eric; Pilati, Camilla; Verret, Benjamin; Blanc, Jean-Frédéric; Balabaud, Charles; Calderaro, Julien; Laurent, Alexis; Letexier, Mélanie; Bioulac-Sage, Paulette; Calvo, Fabien; Zucman-Rossi, Jessica

    2015-10-01

    Hepatocellular carcinomas (HCCs) are liver tumors related to various etiologies, including alcohol intake and infection with hepatitis B (HBV) or C (HCV) virus. Additional risk factors remain to be identified, particularly in patients who develop HCC without cirrhosis. We found clonal integration of adeno-associated virus type 2 (AAV2) in 11 of 193 HCCs. These AAV2 integrations occurred in known cancer driver genes, namely CCNA2 (cyclin A2; four cases), TERT (telomerase reverse transcriptase; one case), CCNE1 (cyclin E1; three cases), TNFSF10 (tumor necrosis factor superfamily member 10; two cases) and KMT2B (lysine-specific methyltransferase 2B; one case), leading to overexpression of the target genes. Tumors with viral integration mainly developed in non-cirrhotic liver (9 of 11 cases) and without known risk factors (6 of 11 cases), suggesting a pathogenic role for AAV2 in these patients. In conclusion, AAV2 is a DNA virus associated with oncogenic insertional mutagenesis in human HCC.

  2. AAV8 capsid variable regions at the two-fold symmetry axis contribute to high liver transduction by mediating nuclear entry and capsid uncoating

    Energy Technology Data Exchange (ETDEWEB)

    Tenney, Rebeca M.; Bell, Christie L.; Wilson, James M., E-mail: wilsonjm@mail.med.upenn.edu

    2014-04-15

    Adeno-associated virus serotype 8 (AAV8) is a promising vector for liver-directed gene therapy. Although efficient uncoating of viral capsids has been implicated in AAV8's robust liver transduction, much about the biology of AAV8 hepatotropism remains unclear. Our study investigated the structural basis of AAV8 liver transduction efficiency by constructing chimeric vector capsids containing sequences derived from AAV8 and AAV2 – a highly homologous yet poorly hepatotropic serotype. Engineered vectors containing capsid variable regions (VR) VII and IX from AAV8 in an AAV2 backbone mediated near AAV8-like transduction in mouse liver, with higher numbers of chimeric genomes detected in whole liver cells and isolated nuclei. Interestingly, chimeric capsids within liver nuclei also uncoated similarly to AAV8 by 6 weeks after administration, in contrast with AAV2, of which a significantly smaller proportion were uncoated. This study links specific AAV capsid regions to the transduction ability of a clinically relevant AAV serotype. - Highlights: • We construct chimeric vectors to identify determinants of AAV8 liver transduction. • An AAV2-based vector with 17 AAV8 residues exhibited high liver transduction in mice. • This vector also surpassed AAV2 in cell entry, nuclear entry and onset of expression. • Most chimeric vector particles were uncoated at 6 weeks, like AAV8 and unlike AAV2. • Chimera retained heparin binding and was antigenically distinct from AAV2 and AAV8.

  3. Resonant snubber inverter

    Science.gov (United States)

    Lai, J.S.; Young, R.W. Sr.; Chen, D.; Scudiere, M.B.; Ott, G.W. Jr.; White, C.P.; McKeever, J.W.

    1997-06-24

    A resonant, snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the main inverter switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter. 14 figs.

  4. Resonant snubber inverter

    Science.gov (United States)

    Lai, Jih-Sheng; Young, Sr., Robert W.; Chen, Daoshen; Scudiere, Matthew B.; Ott, Jr., George W.; White, Clifford P.; McKeever, John W.

    1997-01-01

    A resonant, snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the main inverter switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter.

  5. SEEPAGE/INVERT INTERACTIONS

    International Nuclear Information System (INIS)

    P.S. Domski

    2000-01-01

    As directed by a written development plan (CRWMS M andO 1999a), a conceptual model for water entering the drift and reacting with the invert materials is to be developed. The purpose of this conceptual model is to assist Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department in modeling the geochemical environment within a repository drift, thus allowing PAO to provide a more detailed and complete in-drift geochemical model abstraction, and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near-Field Environment (NFE), Revision 2 (NRC 1999). This AMR also seeks to: (1) Develop a logical conceptual model for physical/chemical interactions between seepage and the invert materials; (2) screen potential processes and reactions that may occur between seepage and invert to evaluate the potential consequences of the interactions; and (3) outline how seepage/invert processes may be quantified. This document provides the conceptual framework for screening out insignificant processes and for identifying and evaluating those seepage/invert interactions that have the potential to be important to subsequent PAO analyses including the Engineered Barrier System (EBS) physical and chemical model abstraction effort. This model has been developed to serve as a basis for the in-drift geochemical analyses performed by PAO. Additionally, the concepts discussed within this report may also apply to certain near and far-field geochemical processes and may have conceptual application within the unsaturated zone (UZ) and saturated zone (SZ) transport modeling efforts. The seepage/invert interactions will not directly affect any principal factors

  6. Tyrosine Mutation in AAV9 Capsid Improves Gene Transfer to the Mouse Lung

    Directory of Open Access Journals (Sweden)

    Sabrina V. Martini

    2016-07-01

    Full Text Available Background/Aims: Adeno-associated virus (AAV vectors are being increasingly used as the vector of choice for in vivo gene delivery and gene therapy for many pulmonary diseases. Recently, it was shown that phosphorylation of surface-exposed tyrosine residues from AAV capsid targets the viral particles for ubiquitination and proteasome-mediated degradation, and mutations of these tyrosine residues lead to highly efficient vector transduction in vitro and in vivo in different organs. In this study, we evaluated the pulmonary transgene expression efficacy of AAV9 vectors containing point mutations in surface-exposed capsid tyrosine residues. Methods: Eighteen C57BL/6 mice were randomly assigned into three groups: (1 a control group (CTRL animals underwent intratracheal (i.t. instillation of saline, (2 the wild-type AAV9 group (WT-AAV9, 1010 vg, and (3 the tyrosine-mutant Y731F AAV9 group (M-AAV9, 1010 vg, which received (i.t. self-complementary AAV9 vectors containing the DNA sequence of enhanced green fluorescence protein (eGFP. Four weeks after instillation, lung mechanics, morphometry, tissue cellularity, gene expression, inflammatory cytokines, and growth factor expression were analyzed. Results: No significant differences were observed in lung mechanics and morphometry among the experimental groups. However, the number of polymorphonuclear cells was higher in the WT-AAV9 group than in the CTRL and M-AAV9 groups, suggesting that the administration of tyrosine-mutant AAV9 vectors was better tolerated. Tyrosine-mutant AAV9 vectors significantly improved transgene delivery to the lung (30% compared with their wild-type counterparts, without eliciting an inflammatory response. Conclusion: Our results provide the impetus for further studies to exploit the use of AAV9 vectors as a tool for pulmonary gene therapy.

  7. Energy-Saving Inverter

    Science.gov (United States)

    Rippel, W. E.; Edwards, D. B.

    1984-01-01

    Commutation by field-effect transistor allows more efficient operation. High voltage field-effect transistor (FET) controls silicon controlled rectifiers (SCR's). Circuit requires only one capacitor and one inductor in commutation circuit: simpler, more efficient, and more economical than conventional inverters. Adaptable to dc-to-dc converters.

  8. Inverter communications using output signal

    Science.gov (United States)

    Chapman, Patrick L.

    2017-02-07

    Technologies for communicating information from an inverter configured for the conversion of direct current (DC) power generated from an alternative source to alternating current (AC) power are disclosed. The technologies include determining information to be transmitted from the inverter over a power line cable connected to the inverter and controlling the operation of an output converter of the inverter as a function of the information to be transmitted to cause the output converter to generate an output waveform having the information modulated thereon.

  9. Inverting the Linear Algebra Classroom

    Science.gov (United States)

    Talbert, Robert

    2014-01-01

    The inverted classroom is a course design model in which students' initial contact with new information takes place outside of class meetings, and students spend class time on high-level sense-making activities. The inverted classroom model is so called because it inverts or "flips" the usual classroom design where typically class…

  10. Quasi-Y-source inverter

    DEFF Research Database (Denmark)

    Siwakoti, Yam Prasad; Blaabjerg, Frede; Loh, Poh Chiang

    2015-01-01

    This paper introduces a new inverter topology called a “quasi-Y-source inverter”. The proposed inverter inherits all the advantages of the original Y-source inverter. In addition, the new topology draws continuous current from the source which is required for many renewable sources. It also has dc...

  11. Milliwatt dc/dc Inverter

    Science.gov (United States)

    Mclyman, C. W.

    1983-01-01

    Compact dc/dc inverter uses single integrated-circuit package containing six inverter gates that generate and amplify 100-kHz square-wave switching signal. Square-wave switching inverts 10-volt local power to isolated voltage at another desired level. Relatively high operating frequency reduces size of filter capacitors required, resulting in small package unit.

  12. Tyrosine-phosphorylation of AAV2 vectors and its consequences on viral intracellular trafficking and transgene expression

    International Nuclear Information System (INIS)

    Zhong Li; Li Baozheng; Jayandharan, Giridhararao; Mah, Cathryn S.; Govindasamy, Lakshmanan; Agbandje-McKenna, Mavis; Herzog, Roland W.

    2008-01-01

    We have documented that epidermal growth factor receptor protein tyrosine kinase (EGFR-PTK) signaling negatively affects intracellular trafficking and transduction efficiency of recombinant adeno-associated virus 2 (AAV2) vectors. Specifically, inhibition of EGFR-PTK signaling leads to decreased ubiquitination of AAV2 capsid proteins, which in turn, facilitates viral nuclear transport by limiting proteasome-mediated degradation of AAV2 vectors. In the present studies, we observed that AAV capsids can indeed be phosphorylated at tyrosine residues by EGFR-PTK in in vitro phosphorylation assays and that phosphorylated AAV capsids retain their structural integrity. However, although phosphorylated AAV vectors enter cells as efficiently as their unphosphorylated counterparts, their transduction efficiency is significantly reduced. This reduction is not due to impaired viral second-strand DNA synthesis since transduction efficiency of both single-stranded AAV (ssAAV) and self-complementary AAV (scAAV) vectors is decreased by ∼ 68% and ∼ 74%, respectively. We also observed that intracellular trafficking of tyrosine-phosphorylated AAV vectors from cytoplasm to nucleus is significantly decreased, which results from ubiquitination of AAV capsids followed by proteasome-mediated degradation, although downstream consequences of capsid ubiquitination may also be affected by tyrosine-phosphorylation. These studies provide new insights into the role of tyrosine-phosphorylation of AAV capsids in various steps in the virus life cycle, which has implications in the optimal use of recombinant AAV vectors in human gene therapy

  13. Significant changes in endogenous retinal gene expression assessed 1 year after a single intraocular injection of AAV-CNTF or AAV-BDNF

    Directory of Open Access Journals (Sweden)

    Chrisna J LeVaillant

    2016-01-01

    Full Text Available Use of viral vectors to deliver therapeutic genes to the central nervous system holds promise for the treatment of neurodegenerative diseases and neurotrauma. Adeno-associated viral (AAV vectors encoding brain-derived neurotrophic factor (BDNF or ciliary derived neurotrophic factor (CNTF promote the viability and regeneration of injured adult rat retinal ganglion cells. However, these growth-inducing transgenes are driven by a constitutively active promoter, thus we examined whether long-term AAV-mediated secretion of BDNF or CNTF affected endogenous retinal gene expression. One year after the intravitreal injection of AAV-green fluorescent protein (GFP, bi-cistronic AAV-BDNF-GFP or AAV-CNTF-GFP, mRNA was extracted and analyzed using custom 96 well polymerase chain reaction arrays. Of 93 test genes, 56% showed significantly altered expression in AAV-BDNF-GFP and/or AAV-CNTF-GFP retinas compared with AAV-GFP controls. Of these genes, 73% showed differential expression in AAV-BDNF versus AAV-CNTF injected eyes. To focus on retinal ganglion cell changes, quantitative polymerase chain reaction was undertaken on mRNA (16 genes obtained from fixed retinal sections in which the ganglion cell layer was enriched. The sign and extent of fold changes in ganglion cell layer gene expression differed markedly from whole retinal samples. Sustained and global alteration in endogenous mRNA expression after gene therapy should be factored into any interpretation of experimental/clinical outcomes, particularly when introducing factors into the central nervous system that require secretion to evoke functionality.

  14. Comparative analysis of DNA nanoparticles and AAVs for ocular gene delivery.

    Directory of Open Access Journals (Sweden)

    Zongchao Han

    Full Text Available Gene therapy is a critical tool for the treatment of monogenic retinal diseases. However, the limited vector capacity of the current benchmark delivery strategy, adeno-associated virus (AAV, makes development of larger capacity alternatives, such as compacted DNA nanoparticles (NPs, critical. Here we conduct a side-by-side comparison of self-complementary AAV and CK30PEG NPs using matched ITR plasmids. We report that although AAVs are more efficient per vector genome (vg than NPs, NPs can drive gene expression on a comparable scale and longevity to AAV. We show that subretinally injected NPs do not leave the eye while some of the AAV-injected animals exhibited vector DNA and GFP expression in the visual pathways of the brain from PI-60 onward. As a result, these NPs have the potential to become a successful alternative for ocular gene therapy, especially for the multitude of genes too large for AAV vectors.

  15. Stochastic p-Bits for Invertible Logic

    Directory of Open Access Journals (Sweden)

    Kerem Yunus Camsari

    2017-07-01

    Full Text Available Conventional semiconductor-based logic and nanomagnet-based memory devices are built out of stable, deterministic units such as standard metal-oxide semiconductor transistors, or nanomagnets with energy barriers in excess of ≈40–60  kT. In this paper, we show that unstable, stochastic units, which we call “p-bits,” can be interconnected to create robust correlations that implement precise Boolean functions with impressive accuracy, comparable to standard digital circuits. At the same time, they are invertible, a unique property that is absent in standard digital circuits. When operated in the direct mode, the input is clamped, and the network provides the correct output. In the inverted mode, the output is clamped, and the network fluctuates among all possible inputs that are consistent with that output. First, we present a detailed implementation of an invertible gate to bring out the key role of a single three-terminal transistorlike building block to enable the construction of correlated p-bit networks. The results for this specific, CMOS-assisted nanomagnet-based hardware implementation agree well with those from a universal model for p-bits, showing that p-bits need not be magnet based: any three-terminal tunable random bit generator should be suitable. We present a general algorithm for designing a Boltzmann machine (BM with a symmetric connection matrix [J] (J_{ij}=J_{ji} that implements a given truth table with p-bits. The [J] matrices are relatively sparse with a few unique weights for convenient hardware implementation. We then show how BM full adders can be interconnected in a partially directed manner (J_{ij}≠J_{ji} to implement large logic operations such as 32-bit binary addition. Hundreds of stochastic p-bits get precisely correlated such that the correct answer out of 2^{33} (≈8×10^{9} possibilities can be extracted by looking at the statistical mode or majority vote of a number of time samples. With perfect

  16. Stochastic p -Bits for Invertible Logic

    Science.gov (United States)

    Camsari, Kerem Yunus; Faria, Rafatul; Sutton, Brian M.; Datta, Supriyo

    2017-07-01

    Conventional semiconductor-based logic and nanomagnet-based memory devices are built out of stable, deterministic units such as standard metal-oxide semiconductor transistors, or nanomagnets with energy barriers in excess of ≈40 - 60 kT . In this paper, we show that unstable, stochastic units, which we call "p -bits," can be interconnected to create robust correlations that implement precise Boolean functions with impressive accuracy, comparable to standard digital circuits. At the same time, they are invertible, a unique property that is absent in standard digital circuits. When operated in the direct mode, the input is clamped, and the network provides the correct output. In the inverted mode, the output is clamped, and the network fluctuates among all possible inputs that are consistent with that output. First, we present a detailed implementation of an invertible gate to bring out the key role of a single three-terminal transistorlike building block to enable the construction of correlated p -bit networks. The results for this specific, CMOS-assisted nanomagnet-based hardware implementation agree well with those from a universal model for p -bits, showing that p -bits need not be magnet based: any three-terminal tunable random bit generator should be suitable. We present a general algorithm for designing a Boltzmann machine (BM) with a symmetric connection matrix [J ] (Ji j=Jj i) that implements a given truth table with p -bits. The [J ] matrices are relatively sparse with a few unique weights for convenient hardware implementation. We then show how BM full adders can be interconnected in a partially directed manner (Ji j≠Jj i) to implement large logic operations such as 32-bit binary addition. Hundreds of stochastic p -bits get precisely correlated such that the correct answer out of 233 (≈8 ×1 09) possibilities can be extracted by looking at the statistical mode or majority vote of a number of time samples. With perfect directivity (Jj i=0 ) a small

  17. Lipidomic Evaluation of Feline Neurologic Disease after AAV Gene Therapy

    Directory of Open Access Journals (Sweden)

    Heather L. Gray-Edwards

    2017-09-01

    Full Text Available GM1 gangliosidosis is a fatal lysosomal disorder, for which there is no effective treatment. Adeno-associated virus (AAV gene therapy in GM1 cats has resulted in a greater than 6-fold increase in lifespan, with many cats remaining alive at >5.7 years of age, with minimal clinical signs. Glycolipids are the principal storage product in GM1 gangliosidosis whose pathogenic mechanism is not completely understood. Targeted lipidomics analysis was performed to better define disease mechanisms and identify markers of disease progression for upcoming clinical trials in humans. 36 sphingolipids and subspecies associated with ganglioside biosynthesis were tested in the cerebrospinal fluid of untreated GM1 cats at a humane endpoint (∼8 months, AAV-treated GM1 cats (∼5 years old, and normal adult controls. In untreated GM1 cats, significant alterations were noted in 16 sphingolipid species, including gangliosides (GM1 and GM3, lactosylceramides, ceramides, sphingomyelins, monohexosylceramides, and sulfatides. Variable degrees of correction in many lipid metabolites reflected the efficacy of AAV gene therapy. Sphingolipid levels were highly predictive of neurologic disease progression, with 11 metabolites having a coefficient of determination (R2 > 0.75. Also, a specific detergent additive significantly increased the recovery of certain lipid species in cerebrospinal fluid samples. This report demonstrates the methodology and utility of targeted lipidomics to examine the pathophysiology of lipid storage disorders.

  18. Stable producer cell lines for adeno-associated virus (AAV) assembly.

    Science.gov (United States)

    Chadeuf, Gilliane; Salvetti, Anna

    2010-10-01

    Stable producer cell lines containing both the rep and cap genes and recombinant adeno-associated virus (rAAV) vectors can be infected with a helper virus to provide reliable and efficient production of rAAV stocks. However, the development of these cell lines is time-consuming. The procedure described here is therefore recommended only for studies requiring the production of high amounts of rAAV, such as preclinical studies performed in large animals.

  19. Inverter ratio failure detector

    Science.gov (United States)

    Wagner, A. P.; Ebersole, T. J.; Andrews, R. E. (Inventor)

    1974-01-01

    A failure detector which detects the failure of a dc to ac inverter is disclosed. The inverter under failureless conditions is characterized by a known linear relationship of its input and output voltages and by a known linear relationship of its input and output currents. The detector includes circuitry which is responsive to the detector's input and output voltages and which provides a failure-indicating signal only when the monitored output voltage is less by a selected factor, than the expected output voltage for the monitored input voltage, based on the known voltages' relationship. Similarly, the detector includes circuitry which is responsive to the input and output currents and provides a failure-indicating signal only when the input current exceeds by a selected factor the expected input current for the monitored output current based on the known currents' relationship.

  20. Potent spinal parenchymal AAV9-mediated gene delivery by subpial injection in adult rats and pigs

    Directory of Open Access Journals (Sweden)

    Atsushi Miyanohara

    2016-01-01

    Full Text Available Effective in vivo use of adeno-associated virus (AAV-based vectors to achieve gene-specific silencing or upregulation in the central nervous system has been limited by the inability to provide more than limited deep parenchymal expression in adult animals using delivery routes with the most clinical relevance (intravenous or intrathecal. Here, we demonstrate that the spinal pia membrane represents the primary barrier limiting effective AAV9 penetration into the spinal parenchyma after intrathecal AAV9 delivery. We develop a novel subpial AAV9 delivery technique and AAV9-dextran formulation. We use these in adult rats and pigs to show (i potent spinal parenchymal transgene expression in white and gray matter including neurons, glial and endothelial cells after single bolus subpial AAV9 delivery; (ii delivery to almost all apparent descending motor axons throughout the length of the spinal cord after cervical or thoracic subpial AAV9 injection; (iii potent retrograde transgene expression in brain motor centers (motor cortex and brain stem; and (iv the relative safety of this approach by defining normal neurological function for up to 6 months after AAV9 delivery. Thus, subpial delivery of AAV9 enables gene-based therapies with a wide range of potential experimental and clinical utilizations in adult animals and human patients.

  1. Multiyear therapeutic benefit of AAV serotypes 2, 6, and 8 delivering factor VIII to hemophilia A mice and dogs.

    Science.gov (United States)

    Jiang, Haiyan; Lillicrap, David; Patarroyo-White, Susannah; Liu, Tongyao; Qian, Xiaobing; Scallan, Ciaran D; Powell, Sandra; Keller, Tracey; McMurray, Morag; Labelle, Andrea; Nagy, Dea; Vargas, Joseph A; Zhou, Shangzhen; Couto, Linda B; Pierce, Glenn F

    2006-07-01

    Hemophilia A, a deficiency of functional coagulation factor VIII (FVIII), is treated via protein replacement therapy. Restoring 1% to 5% of normal blood FVIII activity prevents spontaneous bleeding, making the disease an attractive gene therapy target. Previously, we have demonstrated short-term activity of a liver-specific AAV2 vector expressing canine B-domain-deleted FVIII (cFVIII) in a hemophilia canine model. Here, we report the long-term efficacy and safety of AAV-cFVIII vectors of serotypes 2, 5, 6, and 8 in both hemophilia A mice and dogs. AAV6-cFVIII and AAV8-cFVIII restored physiologic levels of plasma FVIII activity in hemophilia A mice. The improved efficacy is attributed to more efficient gene transfer in liver compared with AAV2 and AAV5. However, supraphysiologic cFVIII levels correlated with the formation of cFVIII-neutralizing antibodies in these mice. Of importance, hemophilia A dogs that received AAV2-cFVIII, AAV6-cFVIII, and AAV8-cFVIII have persistently expressed therapeutic levels of FVIII, without antibody formation or other toxicities, for more than 3 years. However, liver transduction efficiencies are similar between AAV2, AAV6, and AAV8 serotypes in hemophilia A dogs, in contrast to mice. In summary, this is the first report demonstrating multiyear therapeutic efficacy and safety of multiple AAV-cFVIII vectors in hemophilia A dogs and provides the basis for human clinical studies.

  2. Construction of adeno-associated virus packaging plasmids and cells that directly select for AAV helper functions.

    Science.gov (United States)

    Whiteway, Alistair; Deru, Wale; Prentice, H Grant; Anderson, Robert

    2003-12-01

    Recombinant adeno-associated virus type 2 (rAAV) has promise for use as a gene therapy vector. Potential problems in the production of rAAV stocks are both the limited amount of recombinant virus that is produced by traditional methods and the possibility of wild-type replication competent adeno-associated virus (wtAAV) contamination. The presence of these contaminants is largely dependent upon the helper plasmid used. Whilst wtAAV is not a pathogen, the presence of these contaminants is undesirable as they may affect experiments concerning the biology of rAAV. Additionally as protocols using rAAV with altered tropism are becoming more prevalent, it is important that no recombination be permitted that may cause the creation of a replication competent AAV with modified (targeting) capsids. Many experimental protocols require the generation of large amounts of high titre rAAV stocks. We describe the production of several AAV helper plasmids and cell lines designed to achieve this goal. These plasmids possess split AAV rep and cap genes to eliminate the production of wtAAV and they possess a selection mechanism which is operatively linked to expression from the AAV cap gene. This allows positive selection of those cells expressing the highest level of the structural capsid proteins and therefore those cells which yield the highest amount of rAAV.

  3. Evaluation of Dose and Safety of AAV7m8 and AAV8BP2 in the Non-Human Primate Retina.

    Science.gov (United States)

    Ramachandran, Pavitra S; Lee, Vivian; Wei, Zhangyong; Song, Ji Yun; Casal, Giulia; Cronin, Therese; Willett, Keirnan; Huckfeldt, Rachel; Morgan, Jessica I W; Aleman, Tomas S; Maguire, Albert M; Bennett, Jean

    2017-02-01

    Within the next decade, we will see many gene therapy clinical trials for eye diseases, which may lead to treatments for thousands of visually impaired people around the world. To target retinal diseases that affect specific cell types, several recombinant adeno-associated virus (AAV) serotypes have been generated and used successfully in preclinical mouse studies. Because there are numerous anatomic and physiologic differences between the eyes of mice and "men" and because surgical delivery approaches and immunologic responses also differ between these species, this study evaluated the transduction characteristics of two promising new serotypes, AAV7m8 and AAV8BP2, in the retinas of animals that are most similar to those of humans: non-human primates (NHPs). We report that while AAV7m8 efficiently targets a variety of cell types by subretinal injection in NHPs, transduction after intravitreal delivery was mostly restricted to the inner retina at lower doses that did not induce an immune response. AAV8BP2 targets the cone photoreceptors efficiently but bipolar cells inefficiently by subretinal injection. Additionally, transduction by both serotypes in the anterior chamber of the eye and the optic pathway of the brain was observed post-intravitreal delivery. Finally, we assessed immunogenicity, keeping in mind that these AAV capsids may be used in future clinical trials. We found that AAV8BP2 had a better safety profile compared with AAV7m8, even at the highest doses administered. These studies underscore the differences in AAV transduction between mice and primates, highlighting the importance of careful evaluation of therapeutic vectors in NHPs prior to moving to clinical trials.

  4. Advances in PV Inverters

    DEFF Research Database (Denmark)

    Anthon, Alexander

    and preferably low complexity leads to new research demands. This is especially true in the field of low cost residential PV inverters where efficiencies are used as major selling arguments. Traditional converter topologies equipped with conventional Silicon based semiconductors to date reach their limitations......, a replacement of only two switching devices per phase leg can greatly reduce the semiconductor losses. The Hybrid-NPC converter can be seen as an attractive and cost competitive alternative to the Silicon Carbide based converter, also allowing to overcome the major drawbacks with the conventional Silicon IGBT...

  5. Gas cooled traction drive inverter

    Science.gov (United States)

    Chinthavali, Madhu Sudhan

    2013-10-08

    The present invention provides a modular circuit card configuration for distributing heat among a plurality of circuit cards. Each circuit card includes a housing adapted to dissipate heat in response to gas flow over the housing. In one aspect, a gas-cooled inverter includes a plurality of inverter circuit cards, and a plurality of circuit card housings, each of which encloses one of the plurality of inverter cards.

  6. AAV-mediated gene therapy for liver diseases : the prime candidate for clinical application?

    NARCIS (Netherlands)

    van der Laan, Luc J. W.; Wang, Yigang; Tilanus, Hugo W.; Janssen, Harry L. A.; Pan, Qiuwei

    Areas covered: This review provides a summary of current literature on AAV-mediated gene therapies for both inherited and acquired liver diseases and outlines different strategies to overcome current clinical limitations. The unique properties of AAV over other viral vectors are highlighted as well

  7. Γ-Z-Source Inverters

    DEFF Research Database (Denmark)

    Loh, Poh Chiang; Li, Ding; Blaabjerg, Frede

    2013-01-01

    Voltage-type Γ-Z-source inverters are proposed in this letter. They use a unique Γ-shaped impedance network for boosting their output voltage in addition to their usual voltage-buck behavior. Comparing them with other topologies, the proposed inverters use lesser components and a coupled transfor......Voltage-type Γ-Z-source inverters are proposed in this letter. They use a unique Γ-shaped impedance network for boosting their output voltage in addition to their usual voltage-buck behavior. Comparing them with other topologies, the proposed inverters use lesser components and a coupled...

  8. 75 FR 55808 - Prospective Grant of Exclusive License: Development of AAV5 Based Therapeutics To Treat Human...

    Science.gov (United States)

    2010-09-14

    ... particles. The specific brain cells that are targeted by AAV5 belong to both non-neuronal/glial cells and... Thereof'' ; and U.S. Patent 6, 855, 314 entitled ``AAV5 Vector for Transducing Brain Cells and Lung Cells... of delivering nucleic acids to a cell by using the AAV5 vectors and particles. More specifically, the...

  9. Three-Level Z-Source Inverters Using a Single LC Impedance Network

    DEFF Research Database (Denmark)

    Loh, Poh Chiang; Lim, Sok Wei; Gao, Feng

    2007-01-01

    Three-level Z-source inverters are recent single-stage topological solutions proposed for buck-boost energy conversion with all favorable advantages of three-level switching retained. Despite their effectiveness in achieving voltage buck-boost conversion, existing three-level Z-source inverters use...... three-level Z-source inverters, whose output voltage can be stepped down or up using only a single LC impedance network connected between the dc input source and either a neutral-point-clamped (NPC) or dc-link cascaded inverter circuitry. Through careful design of their modulation scheme, both inverters...... can function with the minimum of six device commutations per half carrier cycle (similar to that needed by a traditional buck three-level NPC inverter), while producing the correct volt-sec average and inductive voltage boosting at their ac output terminals. Physically, the designed modulation scheme...

  10. Rod Outer Segment Development Influences AAV-Mediated Photoreceptor Transduction After Subretinal Injection.

    Science.gov (United States)

    Petit, Lolita; Ma, Shan; Cheng, Shun-Yun; Gao, Guangping; Punzo, Claudio

    2017-06-01

    Vectors based on the adeno-associated virus (AAV) are currently the preferred tools for delivering genes to photoreceptors (PR) in small and large animals. AAVs have been applied successfully in various models of PR dystrophies. However, unknown barriers still limit AAV's efficient application in several forms of severe PR degenerations due to insufficient transgene expression and/or treated cells at the time of injection. Optimizations of PR gene therapy strategies will likely benefit from the identification of the cellular factors that influence PR transduction. Interestingly, recent studies have shown that the AAV transduction profile of PRs differs significantly between neonatal and adult mouse retinas after subretinal injection. This phenomenon may provide clues to identify host factors that influence the efficiency of AAV-mediated PR transduction. This study demonstrates that rod outer segments are critical modulators of efficient AAV-mediated rod transduction. During retinal development, rod transduction correlated temporally and spatially with the differentiation order of PRs when vectors were introduced subretinally but not when introduced intravitreally. All subretinally injected vectors had an initial preference to transduce cones in the absence of formed rod outer segments and then displayed a preference for rods as the cells matured, independently of the expression cassette or AAV serotype. Consistent with this observation, altered development of rod outer segments was associated with a strong reduction of rod transduction and an increase in the percentage of transduced cones by 2- to 2.8-fold. A similar increase of cone transduction was observed in the adult retinal degeneration 1 (rd1) retina compared to wild-type mice. These results suggest that the loss of rod outer segments in diseased retinas could markedly affect gene transfer efficiency of AAV vectors by limiting the ability of AAVs to infect dying rods efficiently. This information could be

  11. AAV-CRISPR/Cas9-Mediated Depletion of VEGFR2 Blocks Angiogenesis In Vitro.

    Science.gov (United States)

    Wu, Wenyi; Duan, Yajian; Ma, Gaoen; Zhou, Guohong; Park-Windhol, Cindy; D'Amore, Patricia A; Lei, Hetian

    2017-12-01

    Pathologic angiogenesis is a component of many diseases, including neovascular age-related macular degeneration, proliferation diabetic retinopathy, as well as tumor growth and metastasis. The purpose of this project was to examine whether the system of adeno-associated viral (AAV)-mediated CRISPR (clustered regularly interspaced short palindromic repeats)-associated endonuclease (Cas)9 can be used to deplete expression of VEGF receptor 2 (VEGFR2) in human vascular endothelial cells in vitro and thus suppress its downstream signaling events. The dual AAV system of CRISPR/Cas9 from Streptococcus pyogenes (AAV-SpGuide and -SpCas9) was adapted to edit genomic VEGFR2 in primary human retinal microvascular endothelial cells (HRECs). In this system, the endothelial-specific promoter for intercellular adhesion molecule 2 (ICAM2) was cloned into the dual AAV vectors of SpGuide and SpCas9 for driving expression of green fluorescence protein (GFP) and SpCas9, respectively. These two AAV vectors were applied to production of recombinant AAV serotype 5 (rAAV5), which were used to infect HRECs for depletion of VEGFR2. Protein expression was determined by Western blot; and cell proliferation, migration, as well as tube formation were examined. AAV5 effectively infected vascular endothelial cells (ECs) and retinal pigment epithelial (RPE) cells; the ICAM2 promoter drove expression of GFP and SpCas9 in HRECs, but not in RPE cells. The results showed that the rAAV5-CRISPR/Cas9 depleted VEGFR2 by 80% and completely blocked VEGF-induced activation of Akt, and proliferation, migration as well as tube formation of HRECs. AAV-CRISRP/Cas9-mediated depletion of VEGFR2 is a potential therapeutic strategy for pathologic angiogenesis.

  12. Simplified High-Power Inverter

    Science.gov (United States)

    Edwards, D. B.; Rippel, W. E.

    1984-01-01

    Solid-state inverter simplified by use of single gate-turnoff device (GTO) to commutate multiple silicon controlled rectifiers (SCR's). By eliminating conventional commutation circuitry, GTO reduces cost, size and weight. GTO commutation applicable to inverters of greater than 1-kilowatt capacity. Applications include emergency power, load leveling, drives for traction and stationary polyphase motors, and photovoltaic-power conditioning.

  13. (SPWM) Voltage Source Inverter (VSI)

    African Journals Online (AJOL)

    The quest to achieve less-distorted dc-ac power conversion has resulted in the proliferation of many multilevel inverter configurations. This paper presents an experimental report of a simplified topology for single-phase, SPWM, three-level voltage source inverter wit R-L load. To keep the power circuit component count to a ...

  14. Analisis Harmonisa Inverter PWM Satu Fasa

    OpenAIRE

    Rejeki Simanjorang

    2008-01-01

    Pada tesis ini dianalisis harmonisa inverter PWM satu fasa. Inverter PWM satu fasa yang akan ditinjau adalah inverter satu fasa jembatan penuh (konvensional) dan inverter komposit. Analisis difokuskan pada penentuan pola penyaklaran yang optimum agar pembangkitan harmonisa dan switching losses inverter rendah. Untuk menentukan pola penyaklaran optimum maka dilakukan analisis yang berbasis pada rangkaian ekivalen harmonisa inverter satu fasa. Dengan menggunakan pola penyaklaran optimum, kedua ...

  15. AAV9 supports wide-scale transduction of the CNS and TDP-43 disease modeling in adult rats

    Directory of Open Access Journals (Sweden)

    Kasey L Jackson

    Full Text Available AAV9 has emerged as an efficient adeno-associated virus (AAV serotype for gene transfer to the central nervous system. We have used this technique to study aspects of amyotrophic lateral sclerosis (ALS by administering AAV encoding the ALS-related gene transactive response DNA binding protein of 43 kDa (TDP-43 to neonatal rats. However, inducing the expression in adult subjects would be preferable to mimic the adult onset of symptoms in ALS. We expressed either green fluorescent protein (GFP or TDP-43 in adult rats after an intravenous (i.v. route of administration to attempt wide-scale transduction of the spinal cord for disease modeling. In order to optimize the gene transfer, we made comparisons of efficiency by age, gender, and across several AAV serotypes (AAV1, AAV8, AAV9, and AAV10. The data indicate more efficient neuronal transduction in neonates, with little evidence of glial transduction at either age, no gender-related differences in transduction, and that AAV9 was efficient in adults relative to the other serotypes tested. Based on these data, AAV9 TDP-43 was expressed at three vector doses in adult female rats yielding highly consistent, dose-dependent motor deficits. AAV9 can be delivered i.v. to adult rats to achieve consistent pathophysiological changes and a relevant adult-onset system for disease modeling.

  16. Dual reporter comparative indexing of rAAV pseudotyped vectors in chimpanzee airway.

    Science.gov (United States)

    Flotte, Terence R; Fischer, Anne C; Goetzmann, Jason; Mueller, Christian; Cebotaru, Liudmila; Yan, Ziying; Wang, Lilli; Wilson, James M; Guggino, William B; Engelhardt, John F

    2010-03-01

    Selecting the most efficient recombinant adeno-associated virus (rAAV) serotype for airway gene therapy has been difficult due to cross-specific differences in tropism and immune response between humans and animal models. Chimpanzees--the closest surviving genetic relative of humans--provide a valuable opportunity to select the most effective serotypes for clinical trials in humans. However, designing informative experiments using this protected species is challenging due to limited availability and experimental regulations. We have developed a method using Renilla luciferase (RL) and firefly luciferase (FL) reporters to directly index the relative transduction and immune response of two promising rAAV serotypes following lung coinfection. Analysis of differential luciferase activity in chimpanzee airway brushings demonstrated a 20-fold higher efficiency for rAAV1 over rAAV5 at 90 days, a finding that was similar in polarized human airway epithelia. T-cell responses to AAV5 capsid were stronger than AAV1 capsid. This dual vector indexing approach may be useful in selecting lead vector serotypes for clinical gene therapy and suggests rAAV1 is preferred for cystic fibrosis.

  17. Systemic Correction of Murine Glycogen Storage Disease Type IV by an AAV-Mediated Gene Therapy.

    Science.gov (United States)

    Yi, Haiqing; Zhang, Quan; Brooks, Elizabeth D; Yang, Chunyu; Thurberg, Beth L; Kishnani, Priya S; Sun, Baodong

    2017-03-01

    Deficiency of glycogen branching enzyme (GBE) causes glycogen storage disease type IV (GSD IV), which is characterized by the accumulation of a less branched, poorly soluble form of glycogen called polyglucosan (PG) in multiple tissues. This study evaluates the efficacy of gene therapy with an adeno-associated viral (AAV) vector in a mouse model of adult form of GSD IV (Gbe1 ys/ys ). An AAV serotype 9 (AAV9) vector containing a human GBE expression cassette (AAV-GBE) was intravenously injected into 14-day-old Gbe1 ys/ys mice at a dose of 5 × 10 11 vector genomes per mouse. Mice were euthanized at 3 and 9 months of age. In the AAV-treated mice at 3 months of age, GBE enzyme activity was highly elevated in heart, which is consistent with the high copy number of the viral vector genome detected. GBE activity also increased significantly in skeletal muscles and the brain, but not in the liver. The glycogen content was reduced to wild-type levels in muscles and significantly reduced in the liver and brain. At 9 months of age, though GBE activity was only significantly elevated in the heart, glycogen levels were significantly reduced in the liver, brain, and skeletal muscles of the AAV-treated mice. In addition, the AAV treatment resulted in an overall decrease in plasma activities of alanine transaminase, aspartate transaminase, and creatine kinase, and a significant increase in fasting plasma glucose concentration at 9 months of age. This suggests an alleviation of damage and improvement of function in the liver and muscles by the AAV treatment. This study demonstrated a long-term benefit of a systemic injection of an AAV-GBE vector in Gbe1 ys/ys mice.

  18. Transformerless PV inverters. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Borup, U.

    2009-12-15

    Since the start of the project the market for grid connected PV inverters have developed further. When the project started three - phase inverter were only available in high power systems. The technology developed within this project will enable three phase technology also to be implemented in string inverters for system down to 10 kW. We expect this to be very attractive due to the increased demand for symmetrical feed-in to the grid. The project relevance is therefore high and the sector continues to develop very much driven by technology. Especially the inverter technology is getting a lot of focus. The inverter systems are expected to take a much larger role in supporting the electrical grid in the future. The technology platform developed within the project is prepared to be extended with these utility functionalities. The main results of the project were: 1) A new technology concept for transformer-less inverters has been demonstrated with a number of prototypes. 2) Efficiency above 97,7% has been proven. 3) Efficiency and Maximum power point tracking has been optimized to ensure that almost all energy produced of the panels is transferred to the grid. 4) The platform is developed with a very fast control board, which enables extended functionality as demanding grid supporting functions in the future. Details about cost price and details about the control loop implementation is excluded from the report due to the competitive situation for Danfoss Solar Inverters A/S. (LN)

  19. AAV5-Factor VIII Gene Transfer in Severe Hemophilia A.

    Science.gov (United States)

    Rangarajan, Savita; Walsh, Liron; Lester, Will; Perry, David; Madan, Bella; Laffan, Michael; Yu, Hua; Vettermann, Christian; Pierce, Glenn F; Wong, Wing Y; Pasi, K John

    2017-12-28

    Patients with hemophilia A rely on exogenous factor VIII to prevent bleeding in joints, soft tissue, and the central nervous system. Although successful gene transfer has been reported in patients with hemophilia B, the large size of the factor VIII coding region has precluded improved outcomes with gene therapy in patients with hemophilia A. We infused a single intravenous dose of a codon-optimized adeno-associated virus serotype 5 (AAV5) vector encoding a B-domain-deleted human factor VIII (AAV5-hFVIII-SQ) in nine men with severe hemophilia A. Participants were enrolled sequentially into one of three dose cohorts (low dose [one participant], intermediate dose [one participant], and high dose [seven participants]) and were followed through 52 weeks. Factor VIII activity levels remained at 3 IU or less per deciliter in the recipients of the low or intermediate dose. In the high-dose cohort, the factor VIII activity level was more than 5 IU per deciliter between weeks 2 and 9 after gene transfer in all seven participants, and the level in six participants increased to a normal value (>50 IU per deciliter) that was maintained at 1 year after receipt of the dose. In the high-dose cohort, the median annualized bleeding rate among participants who had previously received prophylactic therapy decreased from 16 events before the study to 1 event after gene transfer, and factor VIII use for participant-reported bleeding ceased in all the participants in this cohort by week 22. The primary adverse event was an elevation in the serum alanine aminotransferase level to 1.5 times the upper limit of the normal range or less. Progression of preexisting chronic arthropathy in one participant was the only serious adverse event. No neutralizing antibodies to factor VIII were detected. The infusion of AAV5-hFVIII-SQ was associated with the sustained normalization of factor VIII activity level over a period of 1 year in six of seven participants who received a high dose, with

  20. Immunological Monitoring to Rationally Guide AAV Gene Therapy

    Directory of Open Access Journals (Sweden)

    Cedrik Michael Britten

    2013-09-01

    Full Text Available Recent successes with adeno-associated virus (AAV-based gene therapies fuel the hope for new treatments for hereditary diseases. Pre-existing as well as therapy-induced immune responses against both AAV and the encoded transgenes have been described and may impact on safety and efficacy of gene-therapy approaches. Consequently, monitoring of vector- and transgene-specific immunity is mandated and may rationally guide clinical development. Next to the humoral immune response, the cellular response is central in our understanding of the host reaction in gene therapy. But in contrast to the monitoring of antibodies, which has matured over many decades, sensitive and robust monitoring of T cells is a relatively new development. To make cellular immune assessments fit for purpose, investigators need to know, control and report the critical assay variables that influence the results. In addition, the quality of immune assays needs to be continuously adjusted to allow for exploratory hypothesis generation in early stages and confirmatory hypothesis validation in later stages of clinical development. The concept of immune assay harmonization which includes use of field-wide benchmarks, harmonization guidelines, and external quality control can support the context-specific evolution of immune assays. Multi-center studies pose particular challenges to sample logistics and quality control of sample specimens. Cooperative groups need to define if immune assessments should be performed in one central facility, in peripheral labs or including a combination of both. Finally, engineered reference samples that contain a defined number of antigen-specific T cells may become broadly applicable tools to control assay performance over time or across institutions.

  1. Nanowire NMOS Logic Inverter Characterization.

    Science.gov (United States)

    Hashim, Yasir

    2016-06-01

    This study is the first to demonstrate characteristics optimization of nanowire N-Channel Metal Oxide Semiconductor (NW-MOS) logic inverter. Noise margins and inflection voltage of transfer characteristics are used as limiting factors in this optimization. A computer-based model used to produce static characteristics of NW-NMOS logic inverter. In this research two circuit configuration of NW-NMOS inverter was studied, in first NW-NMOS circuit, the noise margin for (low input-high output) condition was very low. For second NMOS circuit gives excellent noise margins, and results indicate that optimization depends on applied voltage to the inverter. Increasing gate to source voltage with (2/1) nanowires ratio results better noise margins. Increasing of applied DC load transistor voltage tends to increasing in decreasing noise margins; decreasing this voltage will improve noise margins significantly.

  2. Inverter Ground Fault Overvoltage Testing

    Energy Technology Data Exchange (ETDEWEB)

    Hoke, Andy [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Nelson, Austin [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Chakraborty, Sudipta [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Chebahtah, Justin [SolarCity Corporation, San Mateo, CA (United States); Wang, Trudie [SolarCity Corporation, San Mateo, CA (United States); McCarty, Michael [SolarCity Corporation, San Mateo, CA (United States)

    2015-08-12

    This report describes testing conducted at NREL to determine the duration and magnitude of transient overvoltages created by several commercial PV inverters during ground fault conditions. For this work, a test plan developed by the Forum on Inverter Grid Integration Issues (FIGII) has been implemented in a custom test setup at NREL. Load rejection overvoltage test results were reported previously in a separate technical report.

  3. Assessment of tropism and effectiveness of new primate-derived hybrid recombinant AAV serotypes in the mouse and primate retina.

    Directory of Open Access Journals (Sweden)

    Peter Charbel Issa

    Full Text Available Adeno-associated viral vectors (AAV have been shown to be safe in the treatment of retinal degenerations in clinical trials. Thus, improving the efficiency of viral gene delivery has become increasingly important to increase the success of clinical trials. In this study, structural domains of different rAAV serotypes isolated from primate brain were combined to create novel hybrid recombinant AAV serotypes, rAAV2/rec2 and rAAV2/rec3. The efficacy of these novel serotypes were assessed in wild type mice and in two models of retinal degeneration (the Abca4(-/- mouse which is a model for Stargardt disease and in the Pde6b(rd1/rd1 mouse in vivo, in primate tissue ex-vivo, and in the human-derived SH-SY5Y cell line, using an identical AAV2 expression cassette. We show that these novel hybrid serotypes can transduce retinal tissue in mice and primates efficiently, although no more than AAV2/2 and rAAV2/5 serotypes. Transduction efficiency appeared lower in the Abca4(-/- mouse compared to wild type with all vectors tested, suggesting an effect of specific retinal diseases on the efficiency of gene delivery. Shuffling of AAV capsid domains may have clinical applications for patients who develop T-cell immune responses following AAV gene therapy, as specific peptide antigen sequences could be substituted using this technique prior to vector re-treatments.

  4. The structure of adeno-associated virus serotype 3B (AAV-3B): insights into receptor binding and immune evasion.

    Science.gov (United States)

    Lerch, Thomas F; Xie, Qing; Chapman, Michael S

    2010-07-20

    Adeno-associated viruses (AAVs) are leading candidate vectors for human gene therapy. AAV serotypes have broad cellular tropism and use a variety of cellular receptors. AAV serotype 3 binds to heparan sulfate proteoglycan prior to cell entry and is serologically distinct from other serotypes. The capsid features that distinguish AAV-3B from other serotypes are poorly understood. The structure of AAV-3B has been determined to 2.6A resolution from twinned crystals of an infectious virus. The most distinctive structural features are located in regions implicated in receptor and antibody binding, providing insights into the cell entry mechanisms and antigenic nature of AAVs. We show that AAV-3B has a lower affinity for heparin than AAV-2, which can be rationalized by the distinct features of the AAV-3B capsid. The structure of AAV-3B provides an additional foundation for the future engineering of improved gene therapy vectors with modified receptor binding or antigenic characteristics. Copyright 2010 Elsevier Inc. All rights reserved.

  5. High-titer recombinant adeno-associated virus production utilizing a recombinant herpes simplex virus type I vector expressing AAV-2 Rep and Cap.

    Science.gov (United States)

    Conway, J E; Rhys, C M; Zolotukhin, I; Zolotukhin, S; Muzyczka, N; Hayward, G S; Byrne, B J

    1999-06-01

    Recombinant adeno-associated virus type 2 (rAAV) vectors have recently been used to achieve long-term, high level transduction in vivo. Further development of rAAV vectors for clinical use requires significant technological improvements in large-scale vector production. In order to facilitate the production of rAAV vectors, a recombinant herpes simplex virus type I vector (rHSV-1) which does not produce ICP27, has been engineered to express the AAV-2 rep and cap genes. The optimal dose of this vector, d27.1-rc, for AAV production has been determined and results in a yield of 380 expression units (EU) of AAV-GFP produced from 293 cells following transfection with AAV-GFP plasmid DNA. In addition, d27.1-rc was also efficient at producing rAAV from cell lines that have an integrated AAV-GFP provirus. Up to 480 EU/cell of AAV-GFP could be produced from the cell line GFP-92, a proviral, 293 derived cell line. Effective amplification of rAAV vectors introduced into 293 cells by infection was also demonstrated. Passage of rAAV with d27. 1-rc results in up to 200-fold amplification of AAV-GFP with each passage after coinfection of the vectors. Efficient, large-scale production (>109 cells) of AAV-GFP from a proviral cell line was also achieved and these stocks were free of replication-competent AAV. The described rHSV-1 vector provides a novel, simple and flexible way to introduce the AAV-2 rep and cap genes and helper virus functions required to produce high-titer rAAV preparations from any rAAV proviral construct. The efficiency and potential for scalable delivery of d27.1-rc to producer cell cultures should facilitate the production of sufficient quantities of rAAV vectors for clinical application.

  6. An efficient rHSV-based complementation system for the production of multiple rAAV vector serotypes.

    Science.gov (United States)

    Kang, W; Wang, L; Harrell, H; Liu, J; Thomas, D L; Mayfield, T L; Scotti, M M; Ye, G J; Veres, G; Knop, D R

    2009-02-01

    Recombinant herpes simplex virus type 1 (rHSV)-assisted recombinant adeno-associated virus (rAAV) vector production provides a highly efficient and scalable method for manufacture of clinical grade rAAV vectors. Here, we present an rHSV co-infection system for rAAV production, which uses two ICP27-deficient rHSV constructs, one bearing the rep2 and cap (1, 2 or 9) genes of rAAV, and the second bearing an AAV2 ITR-gene of interest (GOI) cassette. The optimum rAAV production parameters were defined by producing rAAV2/GFP in HEK293 cells, yielding greater than 9000 infectious particles per cell with a 14:1 DNase resistance particle to infectious particle (DRP/ip) ratio. The optimized co-infection parameters were then used to generate large-scale stocks of rAAV1/AAT, which encode the human alpha-1-antitrypsin (hAAT) protein, and purified by column chromatography. The purified vector was extensively characterized by rAAV- and rHSV-specific assays and compared to transfection-made vector for in vivo efficacy in mice through intramuscular injection. The co-infection method was also used to produce rAAV9/AAT for comparison to rAAV1/AAT in vivo. Intramuscular administration of 1 x 10(11) DRP per animal of rHSV-produced rAAV1/AAT and rAAV9/AAT resulted in hAAT protein expression of 5.4 x 10(4) and 9.4 x 10(5) ng ml(-1) serum respectively, the latter being clinically relevant.

  7. Recent developments in recombinant AAV-mediated gene therapy for lung diseases.

    Science.gov (United States)

    Flotte, Terence R

    2005-06-01

    Recent studies have shed light on a number of important obstacles to safe and effective gene transfer to the respiratory tract with recombinant AAV vectors. Among these are blocks at the level of receptor binding and internalizations, evasion of proteasomal degradation, inefficiency of nuclear entry, and nuclear factors that inhibit the conversion of rAAV genomes into active double-stranded DNA form. Other important issues have been the size constraints of the vector, the lack of retention of episomal forms of the vector genome, and immune responses which may limit the efficiency of repeated doses of rAAV. Each of these potential obstacles has been addressed with new vector designs. In addition, the availability of an abundance of novel rAAV serotypes, each with its own receptor tropism, has expanded the range of possibilities for long-term success of gene therapy in the respiratory tract.

  8. Invertibility in L-Topological Spaces

    Directory of Open Access Journals (Sweden)

    Anjaly Jose

    2014-03-01

    Full Text Available In this paper, we extend the concept of invertibility to L-topological spaces and delineate its properties. Then, we study further completely invertible L-topological spaces and introduce two types of invertible L-topologies based on the inverting maps, studying their sums, subspaces and simple extensions.

  9. Cell Cycle-Dependent Expression of Adeno-Associated Virus 2 (AAV2) Rep in Coinfections with Herpes Simplex Virus 1 (HSV-1) Gives Rise to a Mosaic of Cells Replicating either AAV2 or HSV-1.

    Science.gov (United States)

    Franzoso, Francesca D; Seyffert, Michael; Vogel, Rebecca; Yakimovich, Artur; de Andrade Pereira, Bruna; Meier, Anita F; Sutter, Sereina O; Tobler, Kurt; Vogt, Bernd; Greber, Urs F; Büning, Hildegard; Ackermann, Mathias; Fraefel, Cornel

    2017-08-01

    Adeno-associated virus 2 (AAV2) depends on the simultaneous presence of a helper virus such as herpes simplex virus 1 (HSV-1) for productive replication. At the same time, AAV2 efficiently blocks the replication of HSV-1, which would eventually limit its own replication by diminishing the helper virus reservoir. This discrepancy begs the question of how AAV2 and HSV-1 can coexist in a cell population. Here we show that in coinfected cultures, AAV2 DNA replication takes place almost exclusively in S/G 2 -phase cells, while HSV-1 DNA replication is restricted to G 1 phase. Live microscopy revealed that not only wild-type AAV2 (wtAAV2) replication but also reporter gene expression from both single-stranded and double-stranded (self-complementary) recombinant AAV2 vectors preferentially occurs in S/G 2 -phase cells, suggesting that the preference for S/G 2 phase is independent of the nature of the viral genome. Interestingly, however, a substantial proportion of S/G 2 -phase cells transduced by the double-stranded but not the single-stranded recombinant AAV2 vectors progressed through mitosis in the absence of the helper virus. We conclude that cell cycle-dependent AAV2 rep expression facilitates cell cycle-dependent AAV2 DNA replication and inhibits HSV-1 DNA replication. This may limit competition for cellular and viral helper factors and, hence, creates a biological niche for either virus to replicate. IMPORTANCE Adeno-associated virus 2 (AAV2) differs from most other viruses, as it requires not only a host cell for replication but also a helper virus such as an adenovirus or a herpesvirus. This situation inevitably leads to competition for cellular resources. AAV2 has been shown to efficiently inhibit the replication of helper viruses. Here we present a new facet of the interaction between AAV2 and one of its helper viruses, herpes simplex virus 1 (HSV-1). We observed that AAV2 rep gene expression is cell cycle dependent and gives rise to distinct time

  10. Recombinant AAV serotype and capsid mutant comparison for pulmonary gene transfer of alpha-1-antitrypsin using invasive and noninvasive delivery.

    Science.gov (United States)

    Liqun Wang, Rejean; McLaughlin, Thomas; Cossette, Travis; Tang, Qiushi; Foust, Kevin; Campbell-Thompson, Martha; Martino, Ashley; Cruz, Pedro; Loiler, Scott; Mueller, Christian; Flotte, Terence R

    2009-01-01

    Recombinant adeno-associated viral (rAAV) vectors have been widely used in pulmonary gene therapy research. In this study, we evaluated the transduction and expression efficiencies of several AAV serotypes and AAV2 capsid mutants with specific pulmonary targeting ligands in the mouse lung. The noninvasive intranasal delivery was compared with the traditional intratracheal lung delivery. The rAAV8 was the most efficient serotype at expressing alpha-1-antitrypsin (AAT) in the lung among all the tested serotypes and mutants. A dose of 1 x 10(10) vg of rAAV8-CB-AAT transduced a high percentage of cells in the lung when delivered intratrachealy. The serum and the broncho-alveolar lavage fluid (BALF) levels of human AAT (hAAT) were about 6- and 2.5-fold higher, respectively, than those of rAAV5 group. Among the rAAV2 capsid mutants, the rAAV2 capsid mutants that display a peptide sequence from hAAT ("long serpin") indicated a twofold increase in transgene expression. For most vectors, the serum hAAT levels achieved after intranasal delivery were 1/2 to 1/3 of those with the intratracheal method. Overall, rAAV8 was the most promising vector for the future application in gene therapy of pulmonary diseases such as AAT deficiency-related emphysema.

  11. Recombinant AAV Serotype and Capsid Mutant Comparison for Pulmonary Gene Transfer of α-1-Antitrypsin Using Invasive and Noninvasive Delivery

    Science.gov (United States)

    Liqun Wang, Rejean; McLaughlin, Thomas; Cossette, Travis; Tang, Qiushi; Foust, Kevin; Campbell-Thompson, Martha; Martino, Ashley; Cruz, Pedro; Loiler, Scott; Mueller, Christian; Flotte, Terence R

    2008-01-01

    Recombinant adeno-associated viral (rAAV) vectors have been widely used in pulmonary gene therapy research. In this study, we evaluated the transduction and expression efficiencies of several AAV serotypes and AAV2 capsid mutants with specific pulmonary targeting ligands in the mouse lung. The noninvasive intranasal delivery was compared with the traditional intratracheal lung delivery. The rAAV8 was the most efficient serotype at expressing α-1-antitrypsin (AAT) in the lung among all the tested serotypes and mutants. A dose of 1 × 1010 vg of rAAV8-CB-AAT transduced a high percentage of cells in the lung when delivered intratrachealy. The serum and the broncho-alveolar lavage fluid (BALF) levels of human AAT (hAAT) were about 6- and 2.5-fold higher, respectively, than those of rAAV5 group. Among the rAAV2 capsid mutants, the rAAV2 capsid mutants that display a peptide sequence from hAAT (“long serpin”) indicated a twofold increase in transgene expression. For most vectors, the serum hAAT levels achieved after intranasal delivery were 1/2 to 1/3 of those with the intratracheal method. Overall, rAAV8 was the most promising vector for the future application in gene therapy of pulmonary diseases such as AAT deficiency–related emphysema. PMID:18941444

  12. CNS-restricted Transduction and CRISPR/Cas9-mediated Gene Deletion with an Engineered AAV Vector

    Directory of Open Access Journals (Sweden)

    Giridhar Murlidharan

    2016-01-01

    Full Text Available Gene therapy using recombinant adeno-associated viral (AAV vectors is emerging as a promising approach to treat central nervous system disorders such as Spinal muscular atrophy, Batten, Parkinson and Alzheimer disease amongst others. A critical remaining challenge for central nervous system-targeted gene therapy, silencing or gene editing is to limit potential vector dose-related toxicity in off-target cells and organs. Here, we characterize a lab-derived AAV chimeric (AAV2g9, which displays favorable central nervous system attributes derived from both parental counterparts, AAV2 and AAV9. This synthetic AAV strain displays preferential, robust, and widespread neuronal transduction within the brain and decreased glial tropism. Importantly, we observed minimal systemic leakage, decreased sequestration and gene transfer in off-target organs with AAV2g9, when administered into the cerebrospinal fluid. A single intracranial injection of AAV2g9 vectors encoding guide RNAs targeting the schizophrenia risk gene MIR137 (encoding MIR137 in CRISPR/Cas9 knockin mice resulted in brain-specific gene deletion with no detectable events in the liver. This engineered AAV vector is a promising platform for treating neurological disorders through gene therapy, silencing or editing modalities.

  13. Accelerating development of advanced inverters :

    Energy Technology Data Exchange (ETDEWEB)

    Neely, Jason C.; Gonzalez, Sigifredo; Ropp, Michael; Schutz, Dustin

    2013-11-01

    The high penetration of utility interconnected photovoltaic (PV) systems is causing heightened concern over the effect that variable renewable generation will have on the electrical power system (EPS). These concerns have initiated the need to amend the utility interconnection standard to allow advanced inverter control functionalities that provide: (1) reactive power control for voltage support, (2) real power control for frequency support and (3) better tolerance of grid disturbances. These capabilities are aimed at minimizing the negative impact distributed PV systems may have on EPS voltage and frequency. Unfortunately, these advanced control functions may interfere with island detection schemes, and further development of advanced inverter functions requires a study of the effect of advanced functions on the efficacy of antiislanding schemes employed in industry. This report summarizes the analytical, simulation and experimental work to study interactions between advanced inverter functions and anti-islanding schemes being employed in distributed PV systems.

  14. Inverter design for high frequency power distribution

    Science.gov (United States)

    King, R. J.

    1985-01-01

    A class of simple resonantly commutated inverters are investigated for use in a high power (100 KW - 1000 KW) high frequency (10 KHz - 20 KHz) AC power distribution system. The Mapham inverter is found to provide a unique combination of large thyristor turn-off angle and good utilization factor, much better than an alternate 'current-fed' inverter. The effects of loading the Mapham inverter entirely with rectifier loads are investigated by simulation and with an experimental 3 KW 20 KHz inverter. This inverter is found to be well suited to a power system with heavy rectifier loading.

  15. Chromosomal position effects on AAV-mediated gene targeting.

    Science.gov (United States)

    Cornea, Anda M; Russell, David W

    2010-06-01

    The effects of chromosomal position and neighboring genomic elements on gene targeting in human cells remain largely unexplored. To study these, we used a shuttle vector system in which murine leukemia virus (MLV)-based proviral targets present at different chromosomal locations and containing mutations in the neomycin phosphotransferase (neo) gene were corrected by adeno-associated virus (AAV)-mediated gene targeting. Sixteen identical target loci present in HT-1080 human sarcoma cells were all successfully corrected by gene targeting. The gene targeting frequencies varied by as much as 10-fold, and there was a clear bias for correction of one of the targets in clones containing two target sites. The targeting frequency at each site was correlated to the proximity and density of various genomic elements, and we found a significant association of higher targeting frequencies at loci near a subset of dinucleotide microsatellite repeats (r = -0.55, P targeting frequencies at the target loci (r = 0.52, P targeting frequencies. Our results indicate that certain chromosomal positions are preferred sites for gene targeting in human cells.

  16. Advanced Modular Inverter Technology Development

    Energy Technology Data Exchange (ETDEWEB)

    Adam Szczepanek

    2006-02-04

    Electric and hybrid-electric vehicle systems require an inverter to convert the direct current (DC) output of the energy generation/storage system (engine, fuel cells, or batteries) to the alternating current (AC) that vehicle propulsion motors use. Vehicle support systems, such as lights and air conditioning, also use the inverter AC output. Distributed energy systems require an inverter to provide the high quality AC output that energy system customers demand. Today's inverters are expensive due to the cost of the power electronics components, and system designers must also tailor the inverter for individual applications. Thus, the benefits of mass production are not available, resulting in high initial procurement costs as well as high inverter maintenance and repair costs. Electricore, Inc. (www.electricore.org) a public good 501 (c) (3) not-for-profit advanced technology development consortium assembled a highly qualified team consisting of AeroVironment Inc. (www.aerovironment.com) and Delphi Automotive Systems LLC (Delphi), (www.delphi.com), as equal tiered technical leads, to develop an advanced, modular construction, inverter packaging technology that will offer a 30% cost reduction over conventional designs adding to the development of energy conversion technologies for crosscutting applications in the building, industry, transportation, and utility sectors. The proposed inverter allows for a reduction of weight and size of power electronics in the above-mentioned sectors and is scalable over the range of 15 to 500kW. The main objective of this program was to optimize existing AeroVironment inverter technology to improve power density, reliability and producibility as well as develop new topology to reduce line filter size. The newly developed inverter design will be used in automotive and distribution generation applications. In the first part of this program the high-density power stages were redesigned, optimized and fabricated. One of the main

  17. Invertible extensions and growth conditions

    Czech Academy of Sciences Publication Activity Database

    Badea, C.; Müller, Vladimír

    2004-01-01

    Roč. 339, - (2004), s. 21-26 ISSN 1631-073X R&D Projects: GA ČR GA201/03/0041; GA AV ČR KSK1019101 Institutional research plan: CEZ:AV0Z1019905 Keywords : invertible extensions * growth conditions Subject RIV: BA - General Mathematics Impact factor: 0.284, year: 2004

  18. Inverting an Introductory Statistics Classroom

    Science.gov (United States)

    Kraut, Gertrud L.

    2015-01-01

    The inverted classroom allows more in-class time for inquiry-based learning and for working through more advanced problem-solving activities than does the traditional lecture class. The skills acquired in this learning environment offer benefits far beyond the statistics classroom. This paper discusses four ways that can make the inverted…

  19. Intranasal Delivery of Recombinant NT4-NAP/AAV Exerts Potential Antidepressant Effect.

    Science.gov (United States)

    Ma, Xian-Cang; Chu, Zheng; Zhang, Xiao-Ling; Jiang, Wen-Hui; Jia, Min; Dang, Yong-Hui; Gao, Cheng-Ge

    2016-06-01

    The present study was designed to construct a recombinant adeno-associated virus (rAAV) which can express NAP in the brain and examine whether this virus can produce antidepressant effects on C57 BL/6 mice that had been subjected to open field test and forced swimming test, via nose-to-brain pathway. When the recombinant plasmid pGEM-T Easy/NT4-NAP was digested by EcoRI, 297 bp fragments can be obtained and NT4-NAP sequence was consistent with the designed sequence confirmed by DNA sequencing. When the recombinant plasmid pSSCMV/NT4-NAP was digested by EcoRI, 297 bp fragments is visible. Immunohistochemical staining of fibroblasts revealed that expression of NAP was detected in NT4-NAP/AAV group. Intranasal delivery of NT4-NAP/AAV significantly reduced immobility time when the FST was performed after 1 day from the last administration. The effects observed in the FST could not be attributed to non-specific increases in activity since intranasal delivery of NT4-NAP/AAV did not alter the behavior of the mice during the open field test. The results indicated that a recombinant AAV vector which could express NAP in cells was successfully constructed and NAP may be a potential target for therapeutic action of antidepressant treatment.

  20. Convection-enhanced delivery of AAV2-PrPshRNA in prion-infected mice.

    Directory of Open Access Journals (Sweden)

    Misol Ahn

    Full Text Available Prion disease is caused by a single pathogenic protein (PrPSc, an abnormal conformer of the normal cellular prion protein PrPC. Depletion of PrPC in prion knockout mice makes them resistant to prion disease. Thus, gene silencing of the Prnp gene is a promising effective therapeutic approach. Here, we examined adeno-associated virus vector type 2 encoding a short hairpin RNA targeting Prnp mRNA (AAV2-PrP-shRNA to suppress PrPC expression both in vitro and in vivo. AAV2-PrP-shRNA treatment suppressed PrP levels and prevented dendritic degeneration in RML-infected brain aggregate cultures. Infusion of AAV2-PrP-shRNA-eGFP into the thalamus of CD-1 mice showed that eGFP was transported to the cerebral cortex via anterograde transport and the overall PrPC levels were reduced by ∼ 70% within 4 weeks. For therapeutic purposes, we treated RML-infected CD-1 mice with AAV2-PrP-shRNA beginning at 50 days post inoculation. Although AAV2-PrP-shRNA focally suppressed PrPSc formation in the thalamic infusion site by ∼ 75%, it did not suppress PrPSc formation efficiently in other regions of the brain. Survival of mice was not extended compared to the untreated controls. Global suppression of PrPC in the brain is required for successful therapy of prion diseases.

  1. Effective Depletion of Pre-existing Anti-AAV Antibodies Requires Broad Immune Targeting

    Directory of Open Access Journals (Sweden)

    Victoria M. Velazquez

    2017-03-01

    Full Text Available Pre-existing antibodies (Abs to AAV pose a critical challenge for the translation of gene therapies. No effective approach is available to overcome pre-existing Abs. Given the complexity of Ab production, overcoming pre-existing Abs will require broad immune targeting. We generated a mouse model of pre-existing AAV9 Abs to test multiple immunosuppressants, including bortezomib, rapamycin, and prednisolone, individually or in combination. We identified an effective approach combining rapamycin and prednisolone, reducing serum AAV9 Abs by 70%–80% at 4 weeks and 85%–93% at 8 weeks of treatment. The rapamycin plus prednisolone treatment resulted in significant decreases in the frequency of B cells, plasma cells, and IgG-secreting and AAV9-specific Ab-producing plasma cells in bone marrow. The rapamycin plus prednisolone treatment also significantly reduced frequencies of IgD−IgG+ class-switched/FAS+CL7+ germinal center B cells, and of activated CD4+ T cells expressing PD1 and GL7, in spleen. These data suggest that rapamycin plus prednisolone has selective inhibitory effects on both T helper type 2 support of B cell activation in spleen and on bone marrow plasma cell survival, leading to effective AAV9 Abs depletion. This promising immunomodulation approach is highly translatable, and it poses minimal risk in the context of therapeutic benefits promised by gene therapy for severe monogenetic diseases, with a single or possibly a few treatments over a lifetime.

  2. Overload protection system for power inverter

    Science.gov (United States)

    Nagano, S. (Inventor)

    1977-01-01

    An overload protection system for a power inverter utilized a first circuit for monitoring current to the load from the power inverter to detect an overload and a control circuit to shut off the power inverter, when an overload condition was detected. At the same time, a monitoring current inverter was turned on to deliver current to the load at a very low power level. A second circuit monitored current to the load, from the monitoring current inverter, to hold the power inverter off through the control circuit, until the overload condition was cleared so that the control circuit may be deactivated in order for the power inverter to be restored after the monitoring current inverter is turned off completely.

  3. Inverter for Installations with Intermittent Electricity Production

    OpenAIRE

    Ermuraki Iu.; Berzan V.

    2016-01-01

    A new architecture of the inverter used in the convertion of electric energy generated by renewable energy sources is studied in this paper. The distinctive features of this inverter is the special block which compensates pulsing of the current with double frequency, characteristic for these inverters. The switching of electronic keys is realized using the method TCM In this block, like in the inverter, which assures the switching at the voltages near to zero (ZVC). The proposed algorithm of ...

  4. Improved Performance via the Inverted Classroom

    Science.gov (United States)

    Weinstein, Randy D.

    2015-01-01

    This study examined student performance in an inverted thermodynamics course (lectures provided by video outside of class) compared to a traditional lecture class. Students in the inverted class performed better on their exams. Students in the bottom third of the inverted course showed the greatest improvement. These bottom third students had a C…

  5. 21 CFR 184.1859 - Invert sugar.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Invert sugar. 184.1859 Section 184.1859 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1859 Invert sugar. (a) Invert sugar (CAS Reg. No. 8013-17-0) is an aqueous...

  6. Γ-source Neutral Point Clamped Inverter

    DEFF Research Database (Denmark)

    Mo, Wei; Loh, Poh Chiang; Blaabjerg, Frede

    Transformer based Z-source inverters are recently proposed to achieve promising buck-boost capability. They have improved higher buck-boost capability, smaller size and less components count over Z-source inverters. On the other hand, neutral point clamped inverters have less switching stress...

  7. Multilevel Inverter by Cascading Industrial VSI

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Blaabjerg, Frede; Pedersen, John Kim

    2002-01-01

    -source inverter that uses three IGBT triphase inverter modules along with an output transformer to obtain a 3 p.u. multilevel output voltage is introduced. The system yields in high-quality multistep voltage with up to 4 levels and low dv/dt, balanced operation of the inverter modules, each supplying a third...

  8. Better Targeting, Better Efficiency for Wide-scale Neuronal Transduction with the Synapsin Promoter and AAV-PHP.B

    Directory of Open Access Journals (Sweden)

    Kasey L Jackson

    2016-11-01

    Full Text Available Widespread genetic modification of cells in the central nervous system (CNS with a viral vector has become possible and increasingly more efficient. We previously applied an AAV9 vector with the cytomegalovirus/chicken beta-actin hybrid (CBA promoter and achieved wide-scale CNS transduction in neonatal and adult rats. However, this method transduces a variety of tissues in addition to the CNS. Thus we studied intravenous AAV9 gene transfer with a synapsin promoter to better target the neurons. We noted in systematic comparisons that the synapsin promoter drives lower level expression than does the CBA promoter. The engineered AAV-PHP.B serotype was compared with AAV9, and AAV-PHP.B did enhance the efficiency of expression. Combining the synapsin promoter with AAV-PHP.B could therefore be advantageous in terms of combining two refinements of targeting and efficiency. Wide-scale expression was used to model a disease with widespread pathology. Vectors encoding the amyotrophic lateral sclerosis (ALS-related protein TDP-43 with the synapsin promoter and AAV-PHP.B were used for efficient CNS-targeted TDP-43 expression. Intracerebroventricular injections were also explored to limit TDP-43 expression to the CNS. The neuron-selective promoter and the AAV-PHP.B enhanced gene transfer and ALS disease modeling in adult rats.

  9. Single Tyrosine Mutation in AAV8 Vector Capsid Enhances Gene Lung Delivery and Does Not Alter Lung Morphofunction in Mice

    Directory of Open Access Journals (Sweden)

    Sabrina V. Martini

    2014-08-01

    Full Text Available Background/Aims: Vectors derived from adeno-associated viruses (AAVs are important gene delivery tools for treating pulmonary diseases. Phosphorylation of surface-exposed tyrosine residues from AAV2 capsid targets the viral particles for ubiquitination and proteasome-mediated degradation, and mutations of these tyrosine residues lead to highly efficient vector transduction in vitro and in vivo in different organs. We evaluated the pulmonary transduction efficiency of AAV8 vectors containing point mutations in surface-exposed capsid tyrosine residues. Methods: Male C57BL/6 mice (20-25 g, n=24 were randomly assigned into three groups: control group animals received intratracheal (i.t. instillation of saline (50 μl, wild-type AAV8 group, and capsid mutant Y733F AAV8 group, which received (i.t. AAV8 vectors containing the DNA sequence of enhanced green fluorescence protein (eGFP. Four weeks after instillation, lung mechanics and morphometry, vector transduction (immunohistochemistry and mRNA expression of eGFP, and inflammatory cytokines and growth factor expression were analyzed. Results: Tyrosine-mutant AAV8 vectors displayed significantly increased transduction efficiency in the lung compared with their wild-type counterparts. No significant differences were observed in lung mechanics and morphometry between experimental groups. There was no evidence of inflammatory response in any group. Conclusion: AAV8 vectors may be useful for new therapeutic strategies for the treatment of pulmonary diseases.

  10. Hepatitis virus protein X-Phenylalanine Hydroxylase fusion proteins identified in PKU mice treated with AAV-WPRE vectors

    Science.gov (United States)

    Utilizing the Pahenu2 mouse model for phenylketonuria (PKU), we developed an improved expression vector containing the Woodchuck Hepatitis Virus post-transcriptional regulatory element inserted into a rAAV-mPAH construct (rAAV-mPAH-WPRE) for treatment of PKU. Following portal vein delivery of these ...

  11. Better Targeting, Better Efficiency for Wide-Scale Neuronal Transduction with the Synapsin Promoter and AAV-PHP.B.

    Science.gov (United States)

    Jackson, Kasey L; Dayton, Robert D; Deverman, Benjamin E; Klein, Ronald L

    2016-01-01

    Widespread genetic modification of cells in the central nervous system (CNS) with a viral vector has become possible and increasingly more efficient. We previously applied an AAV9 vector with the cytomegalovirus/chicken beta-actin (CBA) hybrid promoter and achieved wide-scale CNS transduction in neonatal and adult rats. However, this method transduces a variety of tissues in addition to the CNS. Thus we studied intravenous AAV9 gene transfer with a synapsin promoter to better target the neurons. We noted in systematic comparisons that the synapsin promoter drives lower level expression than does the CBA promoter. The engineered adeno-associated virus (AAV)-PHP.B serotype was compared with AAV9, and AAV-PHP.B did enhance the efficiency of expression. Combining the synapsin promoter with AAV-PHP.B could therefore be advantageous in terms of combining two refinements of targeting and efficiency. Wide-scale expression was used to model a disease with widespread pathology. Vectors encoding the amyotrophic lateral sclerosis (ALS)-related protein transactive response DNA-binding protein, 43 kDa (TDP-43) with the synapsin promoter and AAV-PHP.B were used for efficient CNS-targeted TDP-43 expression. Intracerebroventricular injections were also explored to limit TDP-43 expression to the CNS. The neuron-selective promoter and the AAV-PHP.B enhanced gene transfer and ALS disease modeling in adult rats.

  12. Recombinant adeno-associated viral (rAAV) vectors mediate efficient gene transduction in cultured neonatal and adult microglia

    Science.gov (United States)

    Su, Wei; Kang, John; Sopher, Bryce; Gillespie, James; Aloi, Macarena S.; Odom, Guy L.; Hopkins, Stephanie; Case, Amanda; Wang, David B.; Chamberlain, Jeffrey S.; Garden, Gwenn A.

    2015-01-01

    Microglia are a specialized population of myeloid cells that mediate CNS innate immune responses. Efforts to identify the cellular and molecular mechanisms that regulate microglia behaviors have been hampered by the lack of effective tools for manipulating gene expression. Cultured microglia are refractory to most chemical and electrical transfection methods, yielding little or no gene delivery and causing toxicity and/or inflammatory activation. Recombinant adeno-associated viral (rAAVs) vectors are non-enveloped, single-stranded DNA vectors commonly used to transduce many primary cell types and tissues. In this study, we evaluated the feasibility and efficiency of utilizing rAAV serotype 2 (rAAV2) to modulate gene expression in cultured microglia. rAAV2 yields high transduction and causes minimal toxicity or inflammatory response in both neonatal and adult microglia. To demonstrate that rAAV transduction can induce functional protein expression, we used rAAV2 expressing Cre-recombinase to successfully excise a LoxP-flanked miR155 gene in cultured microglia. We further evaluated rAAV serotypes 5, 6, 8, and 9, and observed that all efficiently transduced cultured microglia to varying degrees of success and caused little or no alteration in inflammatory gene expression. These results provide strong encouragement for the application of rAAV-mediated gene expression in microglia for mechanistic and therapeutic purposes. PMID:25708596

  13. S4 Grid-Connected Single-Phase Transformerless Inverter for PV Application

    DEFF Research Database (Denmark)

    Ardashir, Jaber Fallah; Siwakoti, Yam Prasad; Sabahi, Mehran

    2016-01-01

    This paper introduces a new single-phase transformerless inverter for grid-connected photovoltaic systems with low leakage current. It consists of four power switches, two diodes, two capacitors and a filter at the output stage. The neutral of the grid is directly connected to the negative terminal...... of the PV source. This results in a constant common-mode voltage and almost zero leakage current. A unipolar Sinusoidal Pulse-Width Modulation (SPWM) technique is used to modulate the inverter to reduce the output current ripple and the filter requirements. The main advantages of this inverter are compact...... clearly verify the performance of the proposed inverter and its practical application for grid-connected PV systems....

  14. Glial promoter selectivity following AAV-delivery to the immature brain.

    Directory of Open Access Journals (Sweden)

    Georg von Jonquieres

    Full Text Available Recombinant adeno-associated virus (AAV vectors are versatile tools for gene transfer to the central nervous system (CNS and proof-of-concept studies in adult rodents have shown that the use of cell type-specific promoters is sufficient to target AAV-mediated transgene expression to glia. However, neurological disorders caused by glial pathology usually have an early onset. Therefore, modelling and treatment of these conditions require expanding the concept of targeted glial transgene expression by promoter selectivity for gene delivery to the immature CNS. Here, we have investigated the AAV-mediated green fluorescent protein (GFP expression driven by the myelin basic protein (MBP or glial fibrillary acidic protein (GFAP promoters in the developing mouse brain. Generally, the extent of transgene expression after infusion at immature stages was widespread and higher than in adults. The GFAP promoter-driven GFP expression was found to be highly specific for astrocytes following vector infusion to the brain of neonates and adults. In contrast, the selectivity of the MBP promoter for oligodendrocytes was poor following neonatal AAV delivery, but excellent after vector injection at postnatal day 10. To extend these findings obtained in naïve mice to a disease model, we performed P10 infusions of AAV-MBP-GFP in aspartoacylase (ASPA-deficient mouse mutants presenting with early onset oligodendrocyte pathology. Spread of GFP expression and selectivity for oligodendrocytes in ASPA-mutants was comparable with our observations in normal animals. Our data suggest that direct AAV infusion to the developing postnatal brain, utilising cellular promoters, results in targeted and long-term transgene expression in glia. This approach will be relevant for disease modelling and gene therapy for the treatment of glial pathology.

  15. Sustained correction of FVII deficiency in dogs using AAV-mediated expression of zymogen FVII

    Science.gov (United States)

    Marcos-Contreras, Oscar A.; Smith, Shannon M.; Bellinger, Dwight A.; Raymer, Robin A.; Merricks, Elizabeth; Faella, Armida; Pavani, Giulia; Zhou, Shangzhen; Nichols, Timothy C.; High, Katherine A.

    2016-01-01

    Factor VII (FVII) deficiency is a rare autosomal recessive bleeding disorder treated by infusion of fresh-frozen plasma, plasma-derived FVII concentrates and low-dose recombinant activated FVII. Clinical data suggest that a mild elevation of plasma FVII levels (>10% normal) results in improved hemostasis. Research dogs with a G96E missense FVII mutation (FVII-G96E) have dogs, we determine the feasibility of a gene therapy approach using liver-directed, adeno-associated viral (AAV) serotype 8 vector delivery of a canine FVII (cFVII) zymogen transgene. FVII-G96E dogs received escalating AAV doses (2E11 to 4.95E13 vector genomes [vg] per kg). Clinically therapeutic expression (15% normal) was attained with as low as 6E11 vg/kg of AAV and has been stable for >1 year (ongoing) without antibody formation to the cFVII transgene. Sustained and supraphysiological expression of 770% normal was observed using 4.95E13 vg/kg of AAV (2.6 years, ongoing). No evidence of pathological activation of coagulation or detrimental animal physiology was observed as platelet counts, d-dimer, fibrinogen levels, and serum chemistries remained normal in all dogs (cumulative 6.4 years). We observed a transient and noninhibitory immunoglobulin G class 2 response against cFVII only in the dog receiving the highest AAV dose. In conclusion, in the only large-animal model representing the majority of FVII mutation types, our data are first to demonstrate the feasibility, safety, and long-term duration of AAV-mediated correction of FVII deficiency. PMID:26702064

  16. Homologous recombination mediates functional recovery of dysferlin deficiency following AAV5 gene transfer.

    Directory of Open Access Journals (Sweden)

    William E Grose

    Full Text Available The dysferlinopathies comprise a group of untreatable muscle disorders including limb girdle muscular dystrophy type 2B, Miyoshi myopathy, distal anterior compartment syndrome, and rigid spine syndrome. As with other forms of muscular dystrophy, adeno-associated virus (AAV gene transfer is a particularly auspicious treatment strategy, however the size of the DYSF cDNA (6.5 kb negates packaging into traditional AAV serotypes known to express well in muscle (i.e. rAAV1, 2, 6, 8, 9. Potential advantages of a full cDNA versus a mini-gene include: maintaining structural-functional protein domains, evading protein misfolding, and avoiding novel epitopes that could be immunogenic. AAV5 has demonstrated unique plasticity with regards to packaging capacity and recombination of virions containing homologous regions of cDNA inserts has been implicated in the generation of full-length transcripts. Herein we show for the first time in vivo that homologous recombination following AAV5.DYSF gene transfer leads to the production of full length transcript and protein. Moreover, gene transfer of full-length dysferlin protein in dysferlin deficient mice resulted in expression levels sufficient to correct functional deficits in the diaphragm and importantly in skeletal muscle membrane repair. Intravascular regional gene transfer through the femoral artery produced high levels of transduction and enabled targeting of specific muscle groups affected by the dysferlinopathies setting the stage for potential translation to clinical trials. We provide proof of principle that AAV5 mediated delivery of dysferlin is a highly promising strategy for treatment of dysferlinopathies and has far-reaching implications for the therapeutic delivery of other large genes.

  17. Identification of the heparin binding site on adeno-associated virus serotype 3B (AAV-3B)

    Energy Technology Data Exchange (ETDEWEB)

    Lerch, Thomas F.; Chapman, Michael S. (Oregon HSU)

    2012-05-24

    Adeno-associated virus is a promising vector for gene therapy. In the current study, the binding site on AAV serotype 3B for the heparan sulfate proteoglycan (HSPG) receptor has been characterized. X-ray diffraction identified a disaccharide binding site at the most positively charged region on the virus surface. The contributions of basic amino acids at this and other sites were characterized using site-directed mutagenesis. Both heparin and cell binding are correlated to positive charge at the disaccharide binding site, and transduction is significantly decreased in AAV-3B vectors mutated at this site to reduce heparin binding. While the receptor attachment sites of AAV-3B and AAV-2 are both in the general vicinity of the viral spikes, the exact amino acids that participate in electrostatic interactions are distinct. Diversity in the mechanisms of cell attachment by AAV serotypes will be an important consideration for the rational design of improved gene therapy vectors.

  18. Fault-tolerant three-level inverter

    Science.gov (United States)

    Edwards, John; Xu, Longya; Bhargava, Brij B.

    2006-12-05

    A method for driving a neutral point clamped three-level inverter is provided. In one exemplary embodiment, DC current is received at a neutral point-clamped three-level inverter. The inverter has a plurality of nodes including first, second and third output nodes. The inverter also has a plurality of switches. Faults are checked for in the inverter and predetermined switches are automatically activated responsive to a detected fault such that three-phase electrical power is provided at the output nodes.

  19. Neutral Point Clamped Npc Type Multilevel Inverter

    Directory of Open Access Journals (Sweden)

    Purohit Sadanand Chandrashekhar

    2015-08-01

    Full Text Available Concept of the multilevel inverter is same as the other inverter which is to converts Direct current DC to Alternating current AC .The inverted current can be at any vital voltage and frequency with the use of pertinent transformers switching and control circuits. From the source like batteries solar panel wind turbine or fuel cell the inverter will convert the DC electricity to AC electricity. In this modern technology Power electronics is very important where it used in a great variety of product. With the high potential in high power for industry multilevel inverter will become most popular for so many applications.

  20. Tailored transgene expression to specific cell types in the central nervous system after peripheral injection with AAV9

    Directory of Open Access Journals (Sweden)

    Jonathan Dashkoff

    2016-01-01

    Full Text Available The capacity of certain adeno-associated virus (AAV vectors to cross the blood–brain barrier after intravenous delivery offers a unique opportunity for noninvasive brain delivery. However, without a well-tailored system, the use of a peripheral route injection may lead to undesirable transgene expression in nontarget cells or organs. To refine this approach, the present study characterizes the transduction profiles of new self-complementary AAV9 (scAAV9 expressing the green fluorescent protein (GFP either under an astrocyte (glial fibrillary acidic (GFA protein or neuronal (Synapsin (Syn promoter, after intravenous injection of adult mice (2 × 1013 vg/kg. ScAAV9-GFA-GFP and scAAV9-Syn-GFP robustly transduce astrocytes (11% and neurons (17%, respectively, without aberrant expression leakage. Interestingly, while the percentages of GFP-positive astrocytes with scAAV9-GFA-GFP are similar to the performances observed with scAAV9-CBA-GFP (broadly active promoter, significant higher percentages of neurons express GFP with scAAV9-Syn-GFP. GFP-positive excitatory as well as inhibitory neurons are observed, as well as motor neurons in the spinal cord. Additionally, both activated (GFAP-positive and resting astrocytes (GFAP-negative express the reporter gene after scAAV9-GFA-GFP injection. These data thoroughly characterize the gene expression specificity of AAVs fitted with neuronal and astrocyte-selective promoters after intravenous delivery, which will prove useful for central nervous system (CNS gene therapy approaches in which peripheral expression of transgene is a concern.

  1. Integrated Inverter And Battery Charger

    Science.gov (United States)

    Rippel, Wally E.

    1988-01-01

    Circuit combines functions of dc-to-ac inversion (for driving ac motor in battery-powered vehicle) and ac-to-dc conversion (for charging battery from ac line when vehicle not in use). Automatically adapts to either mode. Design of integrated inverter/charger eliminates need for duplicate components, saves space, reduces weight and cost of vehicle. Advantages in other applications : load-leveling systems, standby ac power systems, and uninterruptible power supplies.

  2. Effective switching frequency multiplier inverter

    Science.gov (United States)

    Su, Gui-Jia; Peng, Fang Z.

    2007-08-07

    A switching frequency multiplier inverter for low inductance machines that uses parallel connection of switches and each switch is independently controlled according to a pulse width modulation scheme. The effective switching frequency is multiplied by the number of switches connected in parallel while each individual switch operates within its limit of switching frequency. This technique can also be used for other power converters such as DC/DC, AC/DC converters.

  3. A Novel Flying Capacitor Transformerless Inverter for Single-Phase Grid Connected Solar Photovoltaic System

    DEFF Research Database (Denmark)

    Siwakoti, Yam Prasad; Blaabjerg, Frede

    2016-01-01

    This paper proposes a new single-phase flying capacitor transformerless PV inverter for grid-connected photovoltaic (PV) systems. The neutral of the grid can be directly connected to the negative terminal of the source (PV). It consists of four power switches, one diode, one capacitor and a small...

  4. The X gene of adeno-associated virus 2 (AAV2) is involved in viral DNA replication.

    Science.gov (United States)

    Cao, Maohua; You, Hong; Hermonat, Paul L

    2014-01-01

    Adeno-associated virus (AAV) (type 2) is a popular human gene therapy vector with a long active transgene expression period and no reported vector-induced adverse reactions. Yet the basic molecular biology of this virus has not been fully addressed. One potential gene at the far 3' end of the AAV2 genome, previously referred to as X (nt 3929 to 4393), overlapping the 3' end of the cap gene, has never been characterized, although we did previously identify a promoter just up-stream (p81). Computer analysis suggested that X was involved in replication and transcription. The X protein was identified during active AAV2 replication using a polyclonal antibody against a peptide starting at amino acid 98. Reagents for the study of X included an AAV2 deletion mutant (dl78-91), a triple nucleotide substitution mutant that destroys all three 5' AUG-initiation products of X, with no effect on the cap coding sequence, and X-positive-293 cell lines. Here, we found that X up-regulated AAV2 DNA replication in differentiating keratinocytes (without helper virus, autonomous replication) and in various forms of 293 cell-based assays with help from wild type adenovirus type 5 (wt Ad5) or Ad5 helper plasmid (pHelper). The strongest contribution by X was seen in increasing wt AAV2 DNA replication in keratinocytes and dl78-91 in Ad5-infected X-positive-293 cell lines (both having multi-fold effects). Mutating the X gene in pAAV-RC (pAAV-RC-3Xneg) yielded approximately a ∼33% reduction in recombinant AAV vector DNA replication and virion production, but a larger effect was seen when using this same X-knockout AAV helper plasmid in X-positive-293 cell lines versus normal 293 cells (again, multi-fold). Taken together these data strongly suggest that AAV2 X encodes a protein involved in the AAV life cycle, particularly in increasing AAV2 DNA replication, and suggests that further studies are warranted.

  5. Synergistic antitumor effect of AAV-mediated TRAIL expression combined with cisplatin on head and neck squamous cell carcinoma

    International Nuclear Information System (INIS)

    Jiang, Minghong; Liu, Zheng; Xiang, Yang; Ma, Hong; Liu, Shilian; Liu, Yanxin; Zheng, Dexian

    2011-01-01

    Adeno-associated virus-2 (AAV-2)-mediated gene therapy is quite suitable for local or regional application in head and neck cancer squamous cell carcinoma (HNSCC). However, its low transduction efficiency has limited its further development as a therapeutic agent. DNA damaging agents have been shown to enhance AAV-mediated transgene expression. Cisplatin, one of the most effective chemotherapeutic agents, has been recognized to cause cancer cell death by apoptosis with a severe toxicity. This study aims to evaluate the role of cisplatin in AAV-mediated tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) expression and the effect on HNSCC both in vitro and in vivo. Five human HNSCC cell lines were treated with recombinant soluble TRAIL (rsTRAIL) and infected with AAV/TRAIL to estimate the sensitivity of the cancer cells to TRAIL-induced cytotoxicity. KB cells were infected with AAV/EGFP with or without cisplatin pretreatment to evaluate the effect of cisplatin on AAV-mediated gene expression. TRAIL expression was detected by ELISA and Western blot. Cytotoxicity was measured by MTT assay and Western blot analysis for caspase-3 and -8 activations. Following the in vitro experiments, TRAIL expression and its tumoricidal activity were analyzed in nude mice with subcutaneous xenografts of HNSCC. HNSCC cell lines showed different sensitivities to rsTRAIL, and KB cells possessed both highest transduction efficacy of AAV and sensitivity to TRAIL among five cell lines. Preincubation of KB cells with subtherapeutic dosage of cisplatin significantly augmented AAV-mediated transgene expression in a heparin sulfate proteoglycan (HSPG)-dependent manner. Furthermore, cisplatin enhanced the killing efficacy of AAV/TRAIL by 3-fold on KB cell line. The AAV mediated TRAIL expression was observed in the xenografted tumors and significantly enhanced by cisplatin. AAV/TRAIL suppressed the tumors growth and cisplatin augmented the tumoricidal activity by two-fold. Furthermore

  6. AAV-Nrf2 Promotes Protection and Recovery in Animal Models of Oxidative Stress.

    Science.gov (United States)

    Liang, Katharine J; Woodard, Kenton T; Weaver, Mark A; Gaylor, John Paul; Weiss, Ellen R; Samulski, R Jude

    2017-03-01

    NRF2 is a transcription factor that drives antioxidant gene expression in multiple organ systems. We hypothesized that Nrf2 overexpression could be therapeutically applied toward diseases in which redox homeostasis is disrupted. In this study, adeno-associated virus (AAV)-Nrf2 was tested in a mouse model of acute acetaminophen-induced liver toxicity and successfully conferred protection from hepatotoxicity, validating the vector design and early onset of NRF2-mediated protection. Furthermore, therapeutic potential of AAV-Nrf2 in chronic disease also was tested in a light-induced mouse model of age-related macular degeneration. Adult BALB/c mice were intravitreally injected with AAV-Nrf2 and subject to light damage following injection. Retinal thickness and function were monitored following light damage using optical coherence tomography and electroretinography, respectively. By 3 months post-damage, injected eyes had greater retinal thickness compared to uninjected controls. At 1 month post-damage, AAV-Nrf2 injection facilitated full functional recovery from light damage. Our results suggest a therapeutic potential for Nrf2 overexpression in acute and long-term capacities in multiple organ systems, opening up doors for combination gene therapy where replacement gene therapy requires additional therapeutic support to prevent further degeneration. Published by Elsevier Inc.

  7. AAV-Mediated Anterograde Transsynaptic Tagging: Mapping Corticocollicular Input-Defined Neural Pathways for Defense Behaviors.

    Science.gov (United States)

    Zingg, Brian; Chou, Xiao-Lin; Zhang, Zheng-Gang; Mesik, Lukas; Liang, Feixue; Tao, Huizhong Whit; Zhang, Li I

    2017-01-04

    To decipher neural circuits underlying brain functions, viral tracers are widely applied to map input and output connectivity of neuronal populations. Despite the successful application of retrograde transsynaptic viruses for identifying presynaptic neurons of transduced neurons, analogous anterograde transsynaptic tools for tagging postsynaptically targeted neurons remain under development. Here, we discovered that adeno-associated viruses (AAV1 and AAV9) exhibit anterograde transsynaptic spread properties. AAV1-Cre from transduced presynaptic neurons effectively and specifically drives Cre-dependent transgene expression in selected postsynaptic neuronal targets, thus allowing axonal tracing and functional manipulations of the latter input-defined neuronal population. Its application in superior colliculus (SC) reveals that SC neuron subpopulations receiving corticocollicular projections from auditory and visual cortex specifically drive flight and freezing, two different types of defense behavior, respectively. Together with an intersectional approach, AAV-mediated anterograde transsynaptic tagging can categorize neurons by their inputs and molecular identity, and allow forward screening of distinct functional neural pathways embedded in complex brain circuits. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Antidepressant effect of recombinant NT4-NAP/AAV on social isolated mice through intranasal route.

    Science.gov (United States)

    Liu, Fei; Liu, You-Ping; Lei, Gang; Liu, Peng; Chu, Zheng; Gao, Cheng-Ge; Dang, Yong-Hui

    2017-02-07

    The purpose of the present study was to observe the depression-like behavior induced by social isolation; detect the antidepressant effect of a recombinant adeno-associated virus (AAV) expressing NAP on social isolation mice by intranasal delivery. After construction of NT4-NAP/AAV, expression of NAP was confirmed in vitro. 3-week-old C57/BL mice were bred individually in cages as social isolation-rearing. Six weeks later, the first subset of mice underwent behavioral tests and western blot; the second was for enzyme-linked immunosorbent assay. NT4-NAP/AAV was delivered quaque die by nasal administration for consecutive 10 days before behavioral test. Several depression-like behaviors were observed in social isolation mice, including decreased relative sucrose preference, longer immobility time in forced swimming test, lower plasma corticosterone and decreased brain-derived neurotrophic factor in hippocampus. Thus, social isolation procedure appears to be an animal model of depression with good face and construct validity. What's more, the antidepressant effect in social isolation-rearing mice was observed after intranasal administration of NT4-NAP/AAV, suggesting that this might be a promising therapeutic strategy for depressive disorder.

  9. Product-Related Impurities in Clinical-Grade Recombinant AAV Vectors: Characterization and Risk Assessment

    Directory of Open Access Journals (Sweden)

    J. Fraser Wright

    2014-03-01

    Full Text Available Adeno-associated virus (AAV-based vectors expressing therapeutic genes continue to demonstrate great promise for the treatment of a wide variety of diseases and together with other gene transfer vectors represent an emerging new therapeutic paradigm comparable in potential impact on human health to that achieved by recombinant proteins and vaccines. A challenge for the current pipeline of AAV-based investigational products as they advance through clinical development is the identification, characterization and lot-to-lot control of the process- and product-related impurities present in even highly purified preparations. Especially challenging are AAV vector product-related impurities that closely resemble the vector itself and are, in some cases, without clear precedent in established biotherapeutic products. The determination of acceptable levels of these impurities in vectors prepared for human clinical product development, with the goal of new product licensure, requires careful risk and feasibility assessment. This review focuses primarily on the AAV product-related impurities that have been described in vectors prepared for clinical development.

  10. Potent spinal parenchymal AAV9-mediated gene delivery by subpial injection in adult rats and pigs

    Czech Academy of Sciences Publication Activity Database

    Miyanohara, A.; Kamizato, K.; Juhás, Štefan; Juhásová, Jana; Navarro, M.; Maršala, S.; Lukáčová, N.; Hruška-Plocháň, M.; Curtis, E.; Gabel, B.; Ciacci, J. D.; Ahrens, E. T.; Kaspar, B. K.; Cleveland, D.; Maršala, M.

    2016-01-01

    Roč. 3, č. 1 (2016), č. článku 16046. ISSN 2329-0501 R&D Projects: GA MŠk(CZ) LO1609 Institutional support: RVO:67985904 Keywords : AAV9 * rat * pig Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.610, year: 2016

  11. Biological effects of rAAV-caAlk2 coating on structural allograft healing

    DEFF Research Database (Denmark)

    Koefoed, Mette; Ito, Hiromu; Gromov, Kirill

    2005-01-01

    Structural bone allografts often fracture due to their lack of osteogenic and remodeling potential. To overcome these limitations, we utilized allografts coated with recombinant adeno-associated virus (rAAV) that mediate in vivo gene transfer. Using beta-galactosidase as a reporter gene, we show...

  12. CRISPR-Mediated Integration of Large Gene Cassettes Using AAV Donor Vectors

    Directory of Open Access Journals (Sweden)

    Rasmus O. Bak

    2017-07-01

    Full Text Available The CRISPR/Cas9 system has recently been shown to facilitate high levels of precise genome editing using adeno-associated viral (AAV vectors to serve as donor template DNA during homologous recombination (HR. However, the maximum AAV packaging capacity of ∼4.5 kb limits the donor size. Here, we overcome this constraint by showing that two co-transduced AAV vectors can serve as donors during consecutive HR events for the integration of large transgenes. Importantly, the method involves a single-step procedure applicable to primary cells with relevance to therapeutic genome editing. We use the methodology in primary human T cells and CD34+ hematopoietic stem and progenitor cells to site-specifically integrate an expression cassette that, as a single donor vector, would otherwise amount to a total of 6.5 kb. This approach now provides an efficient way to integrate large transgene cassettes into the genomes of primary human cells using HR-mediated genome editing with AAV vectors.

  13. Comparative impact of AAV and enzyme replacement therapy on respiratory and cardiac function in adult Pompe mice

    Directory of Open Access Journals (Sweden)

    Darin J Falk

    Full Text Available Pompe disease is an autosomal recessive genetic disorder characterized by a deficiency of the enzyme responsible for degradation of lysosomal glycogen (acid α-glucosidase (GAA. Cardiac dysfunction and respiratory muscle weakness are primary features of this disorder. To attenuate the progressive and rapid accumulation of glycogen resulting in cardiorespiratory dysfunction, adult Gaa−/− mice were administered a single systemic injection of rAAV2/9-DES-hGAA (AAV9-DES or bimonthly injections of recombinant human GAA (enzyme replacement therapy (ERT. Assessment of cardiac function and morphology was measured 1 and 3 months after initiation of treatment while whole-body plethysmography and diaphragmatic contractile function was evaluated at 3 months post-treatment in all groups. Gaa−/− animals receiving either AAV9-DES or ERT demonstrated a significant improvement in cardiac function and diaphragmatic contractile function as compared to control animals. AAV9-DES treatment resulted in a significant reduction in cardiac dimension (end diastolic left ventricular mass/gram wet weight; EDMc at 3 months postinjection. Neither AAV nor ERT therapy altered minute ventilation during quiet breathing (eupnea. However, breathing frequency and expiratory time were significantly improved in AAV9-DES animals. These results indicate systemic delivery of either strategy improves cardiac function but AAV9-DES alone improves respiratory parameters at 3 months post-treatment in a murine model of Pompe disease.

  14. Dual AAV Gene Therapy for Duchenne Muscular Dystrophy with a 7-kb Mini-Dystrophin Gene in the Canine Model.

    Science.gov (United States)

    Kodippili, Kasun; Hakim, Chady H; Pan, Xiufang; Yang, Hsiao T; Yue, Yongping; Zhang, Yadong; Shin, Jin-Hong; Yang, N Nora; Duan, Dongsheng

    2018-03-01

    Dual adeno-associated virus (AAV) technology was developed in 2000 to double the packaging capacity of the AAV vector. The proof of principle has been demonstrated in various mouse models. Yet, pivotal evidence is lacking in large animal models of human diseases. Here we report expression of a 7-kb canine ΔH2-R15 mini-dystrophin gene using a pair of dual AAV vectors in the canine model of Duchenne muscular dystrophy (DMD). The ΔH2-R15 minigene is by far the most potent synthetic dystrophin gene engineered for DMD gene therapy. We packaged minigene dual vectors in Y731F tyrosine-modified AAV-9 and delivered to the extensor carpi ulnaris muscle of a 12-month-old affected dog at the dose of 2 × 10 13 viral genome particles/vector/muscle. Widespread mini-dystrophin expression was observed 2 months after gene transfer. The missing dystrophin-associated glycoprotein complex was restored. Treatment also reduced muscle degeneration and fibrosis and improved myofiber size distribution. Importantly, dual AAV therapy greatly protected the muscle from eccentric contraction-induced force loss. Our data provide the first clear evidence that dual AAV therapy can be translated to a diseased large mammal. Further development of dual AAV technology may lead to effective therapies for DMD and many other diseases in human patients.

  15. Systemically administered AAV9-sTRAIL combats invasive glioblastoma in a patient-derived orthotopic xenograft model

    Directory of Open Access Journals (Sweden)

    Matheus HW Crommentuijn

    2016-01-01

    Full Text Available Adeno-associated virus (AAV vectors expressing tumoricidal genes injected directly into brain tumors have shown some promise, however, invasive tumor cells are relatively unaffected. Systemic injection of AAV9 vectors provides widespread delivery to the brain and potentially the tumor/microenvironment. Here we assessed AAV9 for potential glioblastoma therapy using two different promoters driving the expression of the secreted anti-cancer agent sTRAIL as a transgene model; the ubiquitously active chicken β-actin (CBA promoter and the neuron-specific enolase (NSE promoter to restrict expression in brain. Intravenous injection of AAV9 vectors encoding a bioluminescent reporter showed similar distribution patterns, although the NSE promoter yielded 100-fold lower expression in the abdomen (liver, with the brain-to-liver expression ratio remaining the same. The main cell types targeted by the CBA promoter were astrocytes, neurons and endothelial cells, while expression by NSE promoter mostly occurred in neurons. Intravenous administration of either AAV9-CBA-sTRAIL or AAV9-NSE-sTRAIL vectors to mice bearing intracranial patient-derived glioblastoma xenografts led to a slower tumor growth and significantly increased survival, with the CBA promoter having higher efficacy. To our knowledge, this is the first report showing the potential of systemic injection of AAV9 vector encoding a therapeutic gene for the treatment of brain tumors.

  16. Recombinant AAV9-TLK1B Administration Ameliorates Fractionated Radiation-Induced Xerostomia

    Science.gov (United States)

    Shanmugam, Prakash Srinivasan Timiri; Dayton, Robert D.; Palaniyandi, Senthilnathan; Abreo, Fleurette; Caldito, Gloria; Klein, Ronald L.

    2013-01-01

    Abstract Salivary glands are highly susceptible to radiation, and patients with head and neck cancer treated with radiotherapy invariably suffer from its distressing side effect, salivary hypofunction. The reduction in saliva disrupts oral functions, and significantly impairs oral health. Previously, we demonstrated that adenoviral-mediated expression of Tousled-like kinase 1B (TLK1B) in rat submandibular glands preserves salivary function after single-dose ionizing radiation. To achieve long-term transgene expression for protection of salivary gland function against fractionated radiation, this study examines the usefulness of recombinant adeno-associated viral vector for TLK1B delivery. Lactated Ringers or AAV2/9 with either TLK1B or GFP expression cassette were retroductally delivered to rat submandibular salivary glands (1011 vg/gland), and animals were exposed, or not, to 20 Gy in eight fractions of 2.5 Gy/day. AAV2/9 transduced predominantly the ductal cells, including the convoluted granular tubules of the submandibular glands. Transgene expression after virus delivery could be detected within 5 weeks, and stable gene expression was observed till the end of study. Pilocarpine-stimulated saliva output measured at 8 weeks after completion of radiation demonstrated >10-fold reduction in salivary flow in saline- and AAV2/9-GFP-treated animals compared with the respective nonirradiated groups (90.8% and 92.5% reduction in salivary flow, respectively). Importantly, there was no decrease in stimulated salivary output after irradiation in animals that were pretreated with AAV2/9-TLK1B (121.5% increase in salivary flow; pgland histology was better preserved after irradiation in TLK1B-treated group, though not significantly, compared with control groups. Single preemptive delivery of AAV2/9-TLK1B averts salivary dysfunction resulting from fractionated radiation. Although AAV2/9 transduces mostly the ductal cells of the gland, their protection against radiation

  17. Recombinant adeno-associated viral (rAAV) vectors mediate efficient gene transduction in cultured neonatal and adult microglia.

    Science.gov (United States)

    Su, Wei; Kang, John; Sopher, Bryce; Gillespie, James; Aloi, Macarena S; Odom, Guy L; Hopkins, Stephanie; Case, Amanda; Wang, David B; Chamberlain, Jeffrey S; Garden, Gwenn A

    2016-01-01

    Microglia are a specialized population of myeloid cells that mediate CNS innate immune responses. Efforts to identify the cellular and molecular mechanisms that regulate microglia behaviors have been hampered by the lack of effective tools for manipulating gene expression. Cultured microglia are refractory to most chemical and electrical transfection methods, yielding little or no gene delivery and causing toxicity and/or inflammatory activation. Recombinant adeno-associated viral (rAAVs) vectors are non-enveloped, single-stranded DNA vectors commonly used to transduce many primary cell types and tissues. In this study, we evaluated the feasibility and efficiency of utilizing rAAV serotype 2 (rAAV2) to modulate gene expression in cultured microglia. rAAV2 yields high transduction and causes minimal toxicity or inflammatory response in both neonatal and adult microglia. To demonstrate that rAAV transduction can induce functional protein expression, we used rAAV2 expressing Cre recombinase to successfully excise a LoxP-flanked miR155 gene in cultured microglia. We further evaluated rAAV serotypes 5, 6, 8, and 9, and observed that all efficiently transduced cultured microglia to varying degrees of success and caused little or no alteration in inflammatory gene expression. These results provide strong encouragement for the application of rAAV-mediated gene expression in microglia for mechanistic and therapeutic purposes. Neonatal microglia are functionally distinct from adult microglia, although the majority of in vitro studies utilize rodent neonatal microglia cultures because of difficulties of culturing adult cells. In addition, cultured microglia are refractory to most methods for modifying gene expression. Here, we developed a novel protocol for culturing adult microglia and evaluated the feasibility and efficiency of utilizing Recombinant Adeno-Associated Virus (rAAV) to modulate gene expression in cultured microglia. © 2015 International Society for

  18. Cascaded Multicell Trans-Z-Source Inverters

    DEFF Research Database (Denmark)

    Li, Ding; Chiang Loh, Poh; Zhu, Miao

    2013-01-01

    Inverters with high-output voltage gain usually face the problem of high-input current flowing through their components. The problem might further be exaggerated if the inverters use high-frequency magnetic devices like transformers or coupled inductors. Leakage inductances of these devices must...... strictly be small to prevent overvoltages caused by switching of their winding currents. To avoid these related problems, cascaded trans-Z-source inverters are proposed. They use multiple magnetic cells in an alternately cascading pattern rather than a single magnetic cell with large turns ratio....... Simulation and experimental results have shown that the multicell inverters can produce the same high-voltage gain, while keeping currents and voltages of the components low. The inverters can also step down their output voltages like a traditional voltage-source inverter without compromising waveform...

  19. Inverter design for four-wire microgrids

    OpenAIRE

    Heredero Peris, Daniel; Pagès Giménez, Marc; Montesinos Miracle, Daniel

    2015-01-01

    This paper presents a PQ four quadrant four-wire three-phase inverter for microgrids integration. The inverter is based in two full-bridge IGBT modules connected in a three-phase configuration plus a threephase parallelized neutral branch. This topology is galvanically isolated through a single-phase transformer bank. The converter operates as a non-ideal voltage-controlled voltage source inverter under AC droop strategy with hot-swap capability based on a dynamic virtual impedance.

  20. Terminal myelocystocele.

    Science.gov (United States)

    Kumar, Raj; Chandra, Anil

    2002-12-01

    Terminal myelocystocele is an unusual form of occult spinal dysraphism. It consists of a cystic dilatation of a low-lying terminal cord herniated posteriorly through a skin covered lumbosacral spina bifida. This condition is often associated with OEIS complex i.e. opmphalocele, exstrophy of the bladder, imperforate anus and spinal abnormality. We studied 4 cases of terminal myelocystocele. They revealed no preoperative neurological deficit. None of these had associated OEIS complex. One of the cyst was unique due to presence of copious amount of pus in its cavity. All four cases underwent successful repair and surgery remained uneventful in all of them. No child showed neurological deterioration during the follow-up.

  1. Common voltage eliminating of SVM diode clamping three-level inverter connected to grid

    DEFF Research Database (Denmark)

    Guo, Yougui; Zeng, Ping; Zhu, Jieqiong

    2011-01-01

    three-level inverter is presented with PLECS. Finally, a series of simulations are carried out. The simulation results tell us PLECS is a very powerful tool to real power circuits modeling. They have also verified that proposed common mode voltage eliminating control strategy of SVM is feasible...... to control the diode clamping three-level inverter. But further research has to be done to get rid of the common mode voltage completely by controlling the voltages of two capacitors at the input terminal....

  2. Biochemical correction of short-chain acyl-coenzyme A dehydrogenase deficiency after portal vein injection of rAAV8-SCAD.

    Science.gov (United States)

    Beattie, Stuart G; Goetzman, Eric; Conlon, Thomas; Germain, Sean; Walter, Glenn; Campbell-Thompson, Martha; Matern, Dietrich; Vockley, Jerry; Flotte, Terence R

    2008-06-01

    Recombinant adeno-associated viral vectors pseudotyped with serotype 5 and 8 capsids (AAV5 and AAV8) have been shown to be efficient gene transfer reagents for the liver. We have produced AAV5 and AAV8 vectors that express mouse short-chain acyl-CoA dehydrogenase (mSCAD) cDNA under the transcriptional control of the cytomegalovirus-chicken beta-actin hybrid promoter. We hypothesized that these vectors would produce sufficient hepatocyte transduction (after administration via the portal vein) and thus sufficient SCAD enzyme to correct the phenotype observed in the SCAD-deficient (BALB/cByJ) mouse, which includes elevated blood butyrylcarnitine and hepatic steatosis. Ten weeks after portal vein injection into 8-week-old mice, AAV8-treated livers contained acyl-CoA dehydrogenase activity (14.3 mU/mg) toward butyryl-CoA, compared with 7.6 mU/mg in mice that received phosphate-buffered saline. Immunohistochemistry showed expression of mSCAD within rAAV8-mSCAD-transduced hepatocytes, as seen by light microscopy. A significant reduction of circulating butyrylcarnitine was seen in AAV5-mSCAD- and AAV8-mSCAD-injected mice. Magnetic resonance spectroscopy of fasted mice demonstrated a significant reduction in relative lipid content within the livers of AAV8-mSCAD-treated mice. These results demonstrate biochemical correction of SCAD deficiency after AAV8-mediated SCAD gene delivery.

  3. Widespread transduction of astrocytes and neurons in the mouse central nervous system after systemic delivery of a self-complementary AAV-PHP.B vector.

    Science.gov (United States)

    Rincon, Melvin Y; de Vin, Filip; Duqué, Sandra I; Fripont, Shelly; Castaldo, Stephanie A; Bouhuijzen-Wenger, Jessica; Holt, Matthew G

    2018-03-09

    Until recently, adeno-associated virus 9 (AAV9) was considered the AAV serotype most effective in crossing the blood-brain barrier (BBB) and transducing cells of the central nervous system (CNS), following systemic injection. However, a newly engineered capsid, AAV-PHP.B, is reported to cross the BBB at even higher efficiency. We investigated how much we could boost CNS transgene expression by using AAV-PHP.B carrying a self-complementary (sc) genome. To allow comparison, 6 weeks old C57BL/6 mice received intravenous injections of scAAV2/9-GFP or scAAV2/PHP.B-GFP at equivalent doses. Three weeks postinjection, transgene expression was assessed in brain and spinal cord. We consistently observed more widespread CNS transduction and higher levels of transgene expression when using the scAAV2/PHP.B-GFP vector. In particular, we observed an unprecedented level of astrocyte transduction in the cortex, when using a ubiquitous CBA promoter. In comparison, neuronal transduction was much lower than previously reported. However, strong neuronal expression (including spinal motor neurons) was observed when the human synapsin promoter was used. These findings constitute the first reported use of an AAV-PHP.B capsid, encapsulating a scAAV genome, for gene transfer in adult mice. Our results underscore the potential of this AAV construct as a platform for safer and more efficacious gene therapy vectors for the CNS.

  4. Transient and intensive pharmacological immunosuppression fails to improve AAV-based liver gene transfer in non-human primates

    Directory of Open Access Journals (Sweden)

    Unzu Carmen

    2012-06-01

    Full Text Available Abstract Background Adeno-associated vectors (rAAV have been used to attain long-term liver gene expression. In humans, the cellular immune response poses a serious obstacle for transgene persistence while neutralizing humoral immunity curtails re-administration. Porphobilinogen deaminase (PBGD haploinsufficiency (acute intermittent porphyria benefits from liver gene transfer in mouse models and clinical trials are about to begin. In this work, we sought to study in non-human primates the feasibility of repeated gene-transfer with intravenous administration of rAAV5 vectors under the effects of an intensive immunosuppressive regimen and to analyze its ability to circumvent T-cell immunity and thereby prolong transgene expression. Methods Three female Macaca fascicularis were intravenously injected with 1x1013 genome copies/kg of rAAV5 encoding the human PBGD. Mycophenolate mofetil (MMF, anti-thymocyte immunoglobulin, methylprednisolone, tacrolimus and rituximab were given in combination during 12 weeks to block T- and B-cell mediated adaptive immune responses in two macaques. Immunodeficient and immunocompetent mice were intravenously injected with 5x1012 genome copies/kg of rAAV5-encoding luciferase protein. Forty days later MMF, tacrolimus and rituximab were daily administrated to ascertain whether the immunosuppressants or their metabolites could interfere with transgene expression. Results Macaques given a rAAV5 vector encoding human PBGD developed cellular and humoral immunity against viral capsids but not towards the transgene. Anti-AAV humoral responses were attenuated during 12 weeks but intensely rebounded following cessation of the immunosuppressants. Accordingly, subsequent gene transfer with a rAAV5 vector encoding green fluorescent protein was impossible. One macaque showed enhanced PBGD expression 25 weeks after rAAV5-pbgd administration but overexpression had not been detected while the animal was under immunosuppression. As

  5. PTEN knockdown with the Y444F mutant AAV2 vector promotes axonal regeneration in the adult optic nerve

    Directory of Open Access Journals (Sweden)

    Zheng-ru Huang

    2018-01-01

    Full Text Available The lack of axonal regeneration is the major cause of vision loss after optic nerve injury in adult mammals. Activating the PI3K/AKT/mTOR signaling pathway has been shown to enhance the intrinsic growth capacity of neurons and to facilitate axonal regeneration in the central nervous system after injury. The deletion of the mTOR negative regulator phosphatase and tensin homolog (PTEN enhances regeneration of adult corticospinal neurons and ganglion cells. In the present study, we used a tyrosine-mutated (Y444F AAV2 vector to efficiently express a short hairpin RNA (shRNA for silencing PTEN expression in retinal ganglion cells. We evaluated cell survival and axonal regeneration in a rat model of optic nerve axotomy. The rats received an intravitreal injection of wildtype AAV2 or Y444F mutant AAV2 (both carrying shRNA to PTEN 4 weeks before optic nerve axotomy. Compared with the wildtype AAV2 vector, the Y444F mutant AAV2 vector enhanced retinal ganglia cell survival and stimulated axonal regeneration to a greater extent 6 weeks after axotomy. Moreover, post-axotomy injection of the Y444F AAV2 vector expressing the shRNA to PTEN rescued ~19% of retinal ganglion cells and induced axons to regenerate near to the optic chiasm. Taken together, our results demonstrate that PTEN knockdown with the Y444F AAV2 vector promotes retinal ganglion cell survival and stimulates long-distance axonal regeneration after optic nerve axotomy. Therefore, the Y444F AAV2 vector might be a promising gene therapy tool for treating optic nerve injury.

  6. Improvements in ANIS and inverted sputter sources

    NARCIS (Netherlands)

    Zwol, N.A. van; Vermeer, A.; Strasters, B.A.

    1984-01-01

    In this article two sputter sources, i.e. an ANIS and an inverted sputter source are described. The ANIS has been changed into a SNICS-like configuration and measurements of the output current for different sputter target geometries are presented. In the inverted sputter source an immersion lens was

  7. Leakage current measurement in transformerless PV inverters

    DEFF Research Database (Denmark)

    Kerekes, Tamas; Sera, Dezso; Mathe, Laszlo

    2012-01-01

    Photovoltaic (PV) installations have seen a huge increase during the last couple of years. Transformerless PV inverters are gaining more share of the total inverter market, due to their high conversion efficiency, small weight and size. Nevertheless safety should have an important role in case...... of these tranformerless systems, due to the missing galvanic isolation. Leakage and fault current measurement is a key issue for these inverter topologies to be able to comply with the required safety standards. This article presents the test results of two different current measurement sensors that were suggested...... to be used in commercial PV inverters for the measurement of leakage and fault ground currents. The German VDE0126–1–1 standard gives the limit for fault and leakage ground currents and all grid connected PV inverters have to comply with these limits and disconnect from the grid in case of a fault....

  8. Inverted base pavements: construction and performance

    KAUST Repository

    Papadopoulos, Efthymios

    2017-05-11

    Inverted base pavements involve a well-compacted granular aggregate base built between a thin asphalt concrete layer and a cement-treated base. Inverted base pavements can be constructed using conventional equipment and procedures but require proper quality control. This study reviews the extensive South African experience and case histories in the USA. Accumulating evidence suggests that inverted base pavements are a viable alternative and can outperform conventional pavements at a lower cost. Inverted base pavements rely on the complementary interaction between layers. The cement-treated base provides a stiff foundation for efficient compaction and constrains the deformation of the stress-sensitive granular aggregate base. The thin asphalt surface layer deforms as a membrane and develops low tensile stress. Additional large-scale field tests should be conducted to assess the performance of inverted base pavement designs in a wide range of conditions relevant to the USA.

  9. Intracisternal delivery of AAV9 results in oligodendrocyte and motor neuron transduction in the whole central nervous system of cats.

    Science.gov (United States)

    Bucher, T; Dubreil, L; Colle, M-A; Maquigneau, M; Deniaud, J; Ledevin, M; Moullier, P; Joussemet, B

    2014-05-01

    Systemic and intracerebrospinal fluid delivery of adeno-associated virus serotype 9 (AAV9) has been shown to achieve widespread gene delivery to the central nervous system (CNS). However, after systemic injection, the neurotropism of the vector has been reported to vary according to age at injection, with greater neuronal transduction in newborns and preferential glial cell tropism in adults. This difference has not yet been reported after cerebrospinal fluid (CSF) delivery. The present study analyzed both neuronal and glial cell transduction in the CNS of cats according to age of AAV9 CSF injection. In both newborns and young cats, administration of AAV9-GFP in the cisterna magna resulted in high levels of motor neurons (MNs) transduction from the cervical (84±5%) to the lumbar (99±1%) spinal cord, demonstrating that the remarkable tropism of AAV9 for MNs is not affected by age at CSF delivery. Surprisingly, numerous oligodendrocytes were also transduced in the brain and in the spinal cord white matter of young cats, but not of neonates, indicating that (i) age of CSF delivery influences the tropism of AAV9 for glial cells and (ii) AAV9 intracisternal delivery could be relevant for both the treatment of MN and demyelinating disorders.

  10. Inhalable delivery of AAV-based MRP4/ABCC4 silencing RNA prevents monocrotaline-induced pulmonary hypertension

    Directory of Open Access Journals (Sweden)

    Caroline Claude

    Full Text Available The ATP-binding cassette transporter MRP4 (encoded by ABCC4 regulates membrane cyclic nucleotides concentrations in arterial cells including smooth muscle cells. MRP4/ABCC4 deficient mice display a reduction in smooth muscle cells proliferation and a prevention of pulmonary hypertension in response to hypoxia. We aimed to study gene transfer of a MRP4/ABCC4 silencing RNA via intratracheal delivery of aerosolized adeno-associated virus 1 (AAV1.shMRP4 or AAV1.control in a monocrotaline-induced model of pulmonary hypertension in rats. Gene transfer was performed at the time of monocrotaline administration and the effect on the development of pulmonary vascular remodeling was assessed 35 days later. AAV1.shMRP4 dose-dependently reduced right ventricular systolic pressure and hypertrophy with a significant reduction with the higher doses (i.e., >1011 DRP/animal as compared to AAV1.control. The higher dose of AAV1.shMRP4 was also associated with a significant reduction in distal pulmonary arteries remodeling. AAV1.shMRP4 was finally associated with a reduction in the expression of ANF, a marker of cardiac hypertrophy. Collectively, these results support a therapeutic potential for downregulation of MRP4 for the treatment of pulmonary artery hypertension.

  11. AAV-mediated RLBP1 gene therapy improves the rate of dark adaptation in Rlbp1 knockout mice

    Directory of Open Access Journals (Sweden)

    Vivian W Choi

    Full Text Available Recessive mutations in RLBP1 cause a form of retinitis pigmentosa in which the retina, before its degeneration leads to blindness, abnormally slowly recovers sensitivity after exposure to light. To develop a potential gene therapy for this condition, we tested multiple recombinant adeno-associated vectors (rAAVs composed of different promoters, capsid serotypes, and genome conformations. We generated rAAVs in which sequences from the promoters of the human RLBP1, RPE65, or BEST1 genes drove the expression of a reporter gene (green fluorescent protein. A promoter derived from the RLBP1 gene mediated expression in the retinal pigment epithelium and Müller cells (the intended target cell types at qualitatively higher levels than in other retinal cell types in wild-type mice and monkeys. With this promoter upstream of the coding sequence of the human RLBP1 gene, we compared the potencies of vectors with an AAV2 versus an AAV8 capsid in transducing mouse retinas, and we compared vectors with a self-complementary versus a single-stranded genome. The optimal vector (scAAV8-pRLBP1-hRLBP1 had serotype 8 capsid and a self-complementary genome. Subretinal injection of scAAV8-pRLBP1-hRLBP1 in Rlbp1 nullizygous mice improved the rate of dark adaptation based on scotopic (rod-plus-cone and photopic (cone electroretinograms (ERGs. The effect was still present after 1 year.

  12. In vivo genome editing in animals using AAV-CRISPR system: applications to translational research of human disease

    Science.gov (United States)

    Lau, Cia-Hin; Suh, Yousin

    2017-01-01

    Adeno-associated virus (AAV) has shown promising therapeutic efficacy with a good safety profile in a wide range of animal models and human clinical trials. With the advent of clustered regulatory interspaced short palindromic repeat (CRISPR)-based genome-editing technologies, AAV provides one of the most suitable viral vectors to package, deliver, and express CRISPR components for targeted gene editing. Recent discoveries of smaller Cas9 orthologues have enabled the packaging of Cas9 nuclease and its chimeric guide RNA into a single AAV delivery vehicle for robust in vivo genome editing. Here, we discuss how the combined use of small Cas9 orthologues, tissue-specific minimal promoters, AAV serotypes, and different routes of administration has advanced the development of efficient and precise in vivo genome editing and comprehensively review the various AAV-CRISPR systems that have been effectively used in animals. We then discuss the clinical implications and potential strategies to overcome off-target effects, immunogenicity, and toxicity associated with CRISPR components and AAV delivery vehicles. Finally, we discuss ongoing non-viral-based ex vivo gene therapy clinical trials to underscore the current challenges and future prospects of CRISPR/Cas9 delivery for human therapeutics. PMID:29333255

  13. AAV-mediated delivery of the transcription factor XBP1s into the striatum reduces mutant Huntingtin aggregation in a mouse model of Huntington's disease

    Energy Technology Data Exchange (ETDEWEB)

    Zuleta, Amparo [Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago (Chile); Center for Molecular Studies of the Cell, Institute of Biomedical Sciences, University of Chile, Santiago (Chile); Vidal, Rene L. [Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago (Chile); Neurounion Biomedical Foundation, Santiago (Chile); Armentano, Donna; Parsons, Geoffrey [Department of Molecular Biology, Genzyme Corporation, 49 New York Avenue, Framingham, MA 01701 (United States); Hetz, Claudio, E-mail: chetz@med.uchile.cl [Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago (Chile); Center for Molecular Studies of the Cell, Institute of Biomedical Sciences, University of Chile, Santiago (Chile); Department of Immunology and Infectious Diseases, Harvard School of Public Health, 651 Huntington Av., Boston, MA 02446 (United States); Neurounion Biomedical Foundation, Santiago (Chile)

    2012-04-13

    Highlights: Black-Right-Pointing-Pointer The contribution of ER stress to HD has not been directly addressed. Black-Right-Pointing-Pointer Expression of XBP1s using AAVs decreases Huntingtin aggregation in vivo. Black-Right-Pointing-Pointer We describe a new in vivo model of HD based on the expression of a large fragment of mHtt-RFP. -- Abstract: Huntington's disease (HD) is caused by mutations that expand a polyglutamine region in the amino-terminal domain of Huntingtin (Htt), leading to the accumulation of intracellular inclusions and progressive neurodegeneration. Recent reports indicate the engagement of endoplasmic reticulum (ER) stress responses in human HD post mortem samples and animal models of the disease. Adaptation to ER stress is mediated by the activation of the unfolded protein response (UPR), an integrated signal transduction pathway that attenuates protein folding stress by controlling the expression of distinct transcription factors including X-Box binding protein 1 (XBP1). Here we targeted the expression of XBP1 on a novel viral-based model of HD. We delivered an active form of XBP1 locally into the striatum of adult mice using adeno-associated vectors (AAVs) and co-expressed this factor with a large fragment of mutant Htt as a fusion protein with RFP (Htt588{sup Q95}-mRFP) to directly visualize the accumulation of Htt inclusions in the brain. Using this approach, we observed a significant reduction in the accumulation of Htt588{sup Q95}-mRFP intracellular inclusion when XBP1 was co-expressed in the striatum. These results contrast with recent findings indicating a protective effect of XBP1 deficiency in neurodegeneration using knockout mice, and suggest a potential use of gene therapy strategies to manipulate the UPR in the context of HD.

  14. A Grid Connected Transformerless Inverter and its Model Predictive Control Strategy with Leakage Current Elimination Capability

    Directory of Open Access Journals (Sweden)

    J. Fallah Ardashir

    2017-06-01

    Full Text Available This paper proposes a new single phase transformerless Photovoltaic (PV inverter for grid connected systems. It consists of six power switches, two diodes, one capacitor and filter at the output stage. The neutral of the grid is directly connected to the negative terminal of the source. This results in constant common mode voltage and zero leakage current. Model Predictive Controller (MPC technique is used to modulate the converter to reduce the output current ripple and filter requirements. The main advantages of this inverter are compact size, low cost, flexible grounding configuration. Due to brevity, the operating principle and analysis of the proposed circuit are presented in brief. Simulation and experimental results of 200W prototype are shown at the end to validate the proposed topology and concept. The results obtained clearly verifies the performance of the proposed inverter and its practical application for grid connected PV systems.

  15. Subpial Adeno-associated Virus 9 (AAV9) Vector Delivery in Adult Mice

    Czech Academy of Sciences Publication Activity Database

    Tadokoro, T.; Miyanohara, A.; Navarro, M.; Kamizato, K.; Juhás, Štefan; Juhásová, Jana; Maršala, S.; Platoshyn, O.; Curtis, E.; Gabel, B.; Ciacci, J. D.; Lukáčová, N.; Bimbová, K.; Maršala, M.

    2017-01-01

    Roč. 125, č. 13 (2017), č. článku e55770. ISSN 1940-087X R&D Projects: GA MŠk(CZ) LO1609 Institutional support: RVO:67985904 Keywords : AAV9 * adult mouse Subject RIV: EI - Biotechnology ; Bionics OBOR OECD: Technologies involving the manipulation of cells, tissues, organs or the whole organism (assisted reproduction) Impact factor: 1.232, year: 2016

  16. Terminal Ballistics

    CERN Document Server

    Rosenberg, Zvi

    2012-01-01

    This book covers the important issues of terminal ballistics in a comprehensive way combining experimental data, numerical simulations and analytical modeling. The first chapter reviews the experimental equipment which are used for ballistic tests and the diagnostics for material characterization under impulsive loading conditions. The second chapter covers essential features of the codes which are used for terminal ballistics such as the Euler vs. Lagrange schemes and meshing techniques, as well as the most popular material models. The third chapter, devoted to the penetration mechanics of rigid penetrators, brings the update of modeling in this field. The fourth chapter deals with plate perforation and the fifth chapter deals with the penetration mechanics of shaped charge jets and eroding long rods. The last two chapters discuss several techniques for the disruption and defeating of the main threats in armor design. Throughout the book the authors demonstrate the advantages of numerical simulations in unde...

  17. A Novel Retinal Ganglion Cell Promoter for Utility in AAV Vectors

    Directory of Open Access Journals (Sweden)

    Killian S. Hanlon

    2017-09-01

    Full Text Available Significant advances in gene therapy have enabled exploration of therapies for inherited retinal disorders, many of which are in preclinical development or clinical evaluation. Gene therapy for retinal conditions has led the way in this growing field. The loss of retinal ganglion cells (RGCs is a hallmark of a number of retinal disorders. As the field matures innovations that aid in refining therapies and optimizing efficacy are in demand. Gene therapies under development for RGC-related disorders, when delivered with recombinant adeno associated vectors (AAV, have typically been expressed from ubiquitous promoter sequences. Here we describe how a novel promoter from the murine Nefh gene was selected to drive transgene expression in RGCs. The Nefh promoter, in an AAV2/2 vector, was shown to drive preferential EGFP expression in murine RGCs in vivo following intravitreal injection. In contrast, EGFP expression from a CMV promoter was observed not only in RGCs, but throughout the inner nuclear layer and in amacrine cells located within the ganglion cell layer (GCL. Of note, the Nefh promoter sequence is sufficiently compact to be readily accommodated in AAV vectors, where transgene size represents a significant constraint. Moreover, this promoter should in principle provide a more targeted and potentially safer alternative for RGC-directed gene therapies.

  18. Biomarkers for disease progression and AAV therapeutic efficacy in feline Sandhoff disease.

    Science.gov (United States)

    Bradbury, Allison M; Gray-Edwards, Heather L; Shirley, Jamie L; McCurdy, Victoria J; Colaco, Alexandria N; Randle, Ashley N; Christopherson, Pete W; Bird, Allison C; Johnson, Aime K; Wilson, Diane U; Hudson, Judith A; De Pompa, Nicholas L; Sorjonen, Donald C; Brunson, Brandon L; Jeyakumar, Mylvaganam; Platt, Frances M; Baker, Henry J; Cox, Nancy R; Sena-Esteves, Miguel; Martin, Douglas R

    2015-01-01

    The GM2 gangliosidoses, Tay-Sachs disease (TSD) and Sandhoff disease (SD), are progressive neurodegenerative disorders that are caused by a mutation in the enzyme β-N-acetylhexosaminidase (Hex). Due to the recent emergence of novel experimental treatments, biomarker development has become particularly relevant in GM2 gangliosidosis as an objective means to measure therapeutic efficacy. Here we describe blood, cerebrospinal fluid (CSF), magnetic resonance imaging (MRI), and electrodiagnostic methods for evaluating disease progression in the feline SD model and application of these approaches to assess AAV-mediated gene therapy. SD cats were treated by intracranial injections of the thalami combined with either the deep cerebellar nuclei or a single lateral ventricle using AAVrh8 vectors encoding feline Hex. Significantly altered in untreated SD cats, blood and CSF based biomarkers were largely normalized after AAV gene therapy. Also reduced after treatment were expansion of the lysosomal compartment in peripheral blood mononuclear cells and elevated activity of secondary lysosomal enzymes. MRI changes characteristic of the gangliosidoses were documented in SD cats and normalized after AAV gene therapy. The minimally invasive biomarkers reported herein should be useful to assess disease progression of untreated SD patients and those in future clinical trials. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Termination unit

    Energy Technology Data Exchange (ETDEWEB)

    Traeholt, Chresten; Willen, Dag; Roden, Mark; Tolbert, Jerry C.; Lindsay, David; Fisher, Paul W.; Nielsen, Carsten Thidemann

    2016-05-03

    Cable end section comprises end-parts of N electrical phases/neutral, and a thermally-insulation envelope comprising cooling fluid. The end-parts each comprises a conductor and are arranged with phase 1 innermost, N outermost surrounded by the neutral, electrical insulation being between phases and N and neutral. The end-parts comprise contacting surfaces located sequentially along the longitudinal extension of the end-section. A termination unit has an insulating envelope connected to a cryostat, special parts at both ends comprising an adapter piece at the cable interface and a closing end-piece terminating the envelope in the end-section. The special parts houses an inlet and/or outlet for cooling fluid. The space between an inner wall of the envelope and a central opening of the cable is filled with cooling fluid. The special part at the end connecting to the cryostat houses an inlet or outlet, splitting cooling flow into cable annular flow and termination annular flow.

  20. Elimination of contaminating cap genes in AAV vector virions reduces immune responses and improves transgene expression in a canine gene therapy model.

    Science.gov (United States)

    Wang, Z; Halbert, C L; Lee, D; Butts, T; Tapscott, S J; Storb, R; Miller, A D

    2014-04-01

    Animal and human gene therapy studies utilizing AAV vectors have shown that immune responses to AAV capsid proteins can severely limit transgene expression. The main source of capsid antigen is that associated with the AAV vectors, which can be reduced by stringent vector purification. A second source of AAV capsid proteins is that expressed from cap genes aberrantly packaged into AAV virions during vector production. This antigen source can be eliminated by the use of a cap gene that is too large to be incorporated into an AAV capsid, such as a cap gene containing a large intron (captron gene). Here, we investigated the effects of elimination of cap gene transfer and of vector purification by CsCl gradient centrifugation on AAV vector immunogenicity and expression following intramuscular injection in dogs. We found that both approaches reduced vector immunogenicity and that combining the two produced the lowest immune responses and highest transgene expression. This combined approach enabled the use of a relatively mild immunosuppressive regimen to promote robust micro-dystrophin gene expression in Duchenne muscular dystrophy-affected dogs. Our study shows the importance of minimizing AAV cap gene impurities and indicates that this improvement in AAV vector production may benefit human applications.

  1. Empty virions in AAV8 vector preparations reduce transduction efficiency and may cause total viral particle dose-limiting side effects

    Directory of Open Access Journals (Sweden)

    Kai Gao

    2014-01-01

    Full Text Available Empty virions are inadvertent by-products of recombinant adeno-associated virus (rAAV packaging process, resulting in vector lots with mixtures of full and empty virions at variable ratios. Impact of empty virions on the efficiency and side effects of rAAV transduction has not been well characterized. Here, we generated partially and completely empty AAV8 virions, fully packaged rAAV8 lots, and mixtures of empty and fully packaged virions with variable ratios of empty virions. The aforementioned dosing formulations of rAAV8 expressing either cellular (EGFP (enhanced green fluorescent protein or nuclear-targeted (n LacZ or secreted (human α1-antitrypsin (hA1AT reporter genes were intravenously injected into two different mouse strains, followed by analyses of transgene expressions and serum alanine aminotransferase (ALT levels at different time points. We found that addition of empty particles to the fixed doses of rAAV8 preparations repressed liver transduction up to 64% (serum hA1AT and 44% (nLacZ in C57BL/6 mice, respectively. The similar trend in inhibiting EGFP expression together with concurrent elevations of serum ALT levels were observed in the BALB/c mice, indicating that empty particles may also exacerbate side effects of rAAV8 EGFP transduction. Our results suggest that removal of empty particles from rAAV preparations may improve efficacy and safety of AAV in clinical applications.

  2. Static Characteristics of the Ferroelectric Transistor Inverter

    Science.gov (United States)

    Mitchell, Cody; Laws, crystal; MacLeond, Todd C.; Ho, Fat D.

    2010-01-01

    The inverter is one of the most fundamental building blocks of digital logic, and it can be used as the foundation for understanding more complex logic gates and circuits. This paper presents the characteristics of an inverter circuit using a ferroelectric field-effect transistor. The voltage transfer characteristics are analyzed with respect to varying parameters such as supply voltage, input voltage, and load resistance. The effects of the ferroelectric layer between the gate and semiconductor are examined, and comparisons are made between the inverters using ferroelectric transistors and those using traditional MOSFETs.

  3. Switching Characteristics of Ferroelectric Transistor Inverters

    Science.gov (United States)

    Laws, Crystal; Mitchell, Coey; MacLeod, Todd C.; Ho, Fat D.

    2010-01-01

    This paper presents the switching characteristics of an inverter circuit using a ferroelectric field effect transistor, FeFET. The propagation delay time characteristics, phl and plh are presented along with the output voltage rise and fall times, rise and fall. The propagation delay is the time-delay between the V50% transitions of the input and output voltages. The rise and fall times are the times required for the output voltages to transition between the voltage levels V10% and V90%. Comparisons are made between the MOSFET inverter and the ferroelectric transistor inverter.

  4. AAV2-mediated in vivo immune gene therapy of solid tumours

    LENUS (Irish Health Repository)

    Collins, Sara A

    2010-12-20

    Abstract Background Many strategies have been adopted to unleash the potential of gene therapy for cancer, involving a wide range of therapeutic genes delivered by various methods. Immune therapy has become one of the major strategies adopted for cancer gene therapy and seeks to stimulate the immune system to target tumour antigens. In this study, the feasibility of AAV2 mediated immunotherapy of growing tumours was examined, in isolation and combined with anti-angiogenic therapy. Methods Immune-competent Balb\\/C or C57 mice bearing subcutaneous JBS fibrosarcoma or Lewis Lung Carcinoma (LLC) tumour xenografts respectively were treated by intra-tumoural administration of AAV2 vector encoding the immune up-regulating cytokine granulocyte macrophage-colony stimulating factor (GM-CSF) and the co-stimulatory molecule B7-1 to subcutaneous tumours, either alone or in combination with intra-muscular (IM) delivery of AAV2 vector encoding Nk4 14 days prior to tumour induction. Tumour growth and survival was monitored for all animals. Cured animals were re-challenged with tumourigenic doses of the original tumour type. In vivo cytotoxicity assays were used to investigate establishment of cell-mediated responses in treated animals. Results AAV2-mediated GM-CSF, B7-1 treatment resulted in a significant reduction in tumour growth and an increase in survival in both tumour models. Cured animals were resistant to re-challenge, and induction of T cell mediated anti-tumour responses were demonstrated. Adoptive transfer of splenocytes to naïve animals prevented tumour establishment. Systemic production of Nk4 induced by intra-muscular (IM) delivery of Nk4 significantly reduced subcutaneous tumour growth. However, combination of Nk4 treatment with GM-CSF, B7-1 therapy reduced the efficacy of the immune therapy. Conclusions Overall, this study demonstrates the potential for in vivo AAV2 mediated immune gene therapy, and provides data on the inter-relationship between tumour

  5. Reactive power and voltage control strategy based on dynamic and adaptive segment for DG inverter

    Science.gov (United States)

    Zhai, Jianwei; Lin, Xiaoming; Zhang, Yongjun

    2018-03-01

    The inverter of distributed generation (DG) can support reactive power to help solve the problem of out-of-limit voltage in active distribution network (ADN). Therefore, a reactive voltage control strategy based on dynamic and adaptive segment for DG inverter is put forward to actively control voltage in this paper. The proposed strategy adjusts the segmented voltage threshold of Q(U) droop curve dynamically and adaptively according to the voltage of grid-connected point and the power direction of adjacent downstream line. And then the reactive power reference of DG inverter can be got through modified Q(U) control strategy. The reactive power of inverter is controlled to trace the reference value. The proposed control strategy can not only control the local voltage of grid-connected point but also help to maintain voltage within qualified range considering the terminal voltage of distribution feeder and the reactive support for adjacent downstream DG. The scheme using the proposed strategy is compared with the scheme without the reactive support of DG inverter and the scheme using the Q(U) control strategy with constant segmented voltage threshold. The simulation results suggest that the proposed method has a significant improvement on solving the problem of out-of-limit voltage, restraining voltage variation and improving voltage quality.

  6. Inverter Output Filter Effect on PWM Motor Drives of a Flywheel Energy Storage System

    Science.gov (United States)

    Santiago, Walter

    2004-01-01

    NASA Glenn Research Center (GRC) has been involved in the research and development of high speed flywheel systems for small satellite energy storage and attitude control applications. One research and development area has been the minimization of the switching noise produced by the pulsed width modulated (PWM) inverter that drives the flywheel permanent magnet motor/generator (PM M/G). This noise can interfere with the flywheel M/G hardware and the system avionics hampering the full speed performance of the flywheel system. One way to attenuate the inverter switching noise is by placing an AC filter at the three phase output terminals of the inverter with the filter neutral point connected to the DC link (DC bus) midpoint capacitors. The main benefit of using an AC filter in this fashion is the significant reduction of the inverter s high dv/dt switching and its harmonics components. Additionally, common mode (CM) and differential mode (DM) voltages caused by the inverter s high dv/dt switching are also reduced. Several topologies of AC filters have been implemented and compared. One AC filter topology consists of a two-stage R-L-C low pass filter. The other topology consists of the same two-stage R-L-C low pass filter with a series connected trap filter (an inductor and capacitor connected in parallel). This paper presents the analysis, design and experimental results of these AC filter topologies and the comparison between the no filter case and conventional AC filter.

  7. AAV Vector-Mediated Gene Delivery to Substantia Nigra Dopamine Neurons: Implications for Gene Therapy and Disease Models

    Directory of Open Access Journals (Sweden)

    Katrina Albert

    2017-02-01

    Full Text Available Gene delivery using adeno-associated virus (AAV vectors is a widely used method to transduce neurons in the brain, especially due to its safety, efficacy, and long-lasting expression. In addition, by varying AAV serotype, promotor, and titer, it is possible to affect the cell specificity of expression or the expression levels of the protein of interest. Dopamine neurons in the substantia nigra projecting to the striatum, comprising the nigrostriatal pathway, are involved in movement control and degenerate in Parkinson′s disease. AAV-based gene targeting to the projection area of these neurons in the striatum has been studied extensively to induce the production of neurotrophic factors for disease-modifying therapies for Parkinson′s disease. Much less emphasis has been put on AAV-based gene therapy targeting dopamine neurons in substantia nigra. We will review the literature related to targeting striatum and/or substantia nigra dopamine neurons using AAVs in order to express neuroprotective and neurorestorative molecules, as well as produce animal disease models of Parkinson′s disease. We discuss difficulties in targeting substantia nigra dopamine neurons and their vulnerability to stress in general. Therefore, choosing a proper control for experimental work is not trivial. Since the axons along the nigrostriatal tract are the first to degenerate in Parkinson′s disease, the location to deliver the therapy must be carefully considered. We also review studies using AAV-a-synuclein (a-syn to target substantia nigra dopamine neurons to produce an α-syn overexpression disease model in rats. Though these studies are able to produce mild dopamine system degeneration in the striatum and substantia nigra and some behavioural effects, there are studies pointing to the toxicity of AAV-carrying green fluorescent protein (GFP, which is often used as a control. Therefore, we discuss the potential difficulties in overexpressing proteins in general in

  8. An AAV9 coding for frataxin clearly improved the symptoms and prolonged the life of Friedreich ataxia mouse models

    Directory of Open Access Journals (Sweden)

    Catherine Gérard

    2014-01-01

    Full Text Available Friedreich ataxia (FRDA is a genetic disease due to increased repeats of the GAA trinucleotide in intron 1 of the frataxin gene. This mutation leads to a reduced expression of frataxin. We have produced an adeno-associated virus (AAV9 coding for human frataxin (AAV9-hFXN. This AAV was delivered by intraperitoneal (IP injection to young conditionally knockout mice in which the frataxin gene had been knocked-out in some tissues during embryogenesis by breeding them with mice expressing the Cre recombinase gene under the muscle creatine kinase (MCK or the neuron-specific enolase (NSE promoter. In the first part of the study, different doses of virus were tested from 6 × 1011 v.p. to 6 × 109 v.p. in NSE-cre mice and all leading to an increase in life spent of the mice. The higher and the lower dose were also tested in MCK-cre mice. A single administration of the AAV9-hFXN at 6 × 1011 v.p. more than doubled the life of these mice. In fact the MCK-cre mice treated with the AAV9-hFXN were sacrificed for further molecular investigations at the age of 29 weeks without apparent symptoms. Echography analysis of the heart function clearly indicated that the cardiac systolic function was better preserved in the mice that received 6 × 1011 v.p. of AAV9-hFXN. The human frataxin protein was detected by ELISA in the heart, brain, muscles, kidney, and liver with the higher dose of virus in both mouse models. Thus, gene therapy with an AAV9-hFXN is a potential treatment of FRDA.

  9. Inverted CERN School of Computing

    CERN Document Server

    IT Department

    2011-01-01

      The 5th edition of the Inverted CERN School of Computing (iCSC, “Where students turn into teachers”) will take place next Thursday and Friday (3 and 4 of March) at CERN, Building 31 - IT Amphitheatre - Third Floor. Attendance is free and open to everyone. The programme is designed so that you can attend the lectures that interest you. This year highlights: Cloud Computing, Software Engineering, Cryptography Registration is not mandatory, but will allow you to obtain a copy of the full booklet (first registered, first served). Programme overview: Thursday 3 March 2011 10:00 - 10:15 Introduction School opening 10:15 - 11:10 Lecture 1 Virtualization: what it is, how it works – Luigi Gallerani 11:20 - 12:15 Lecture 2 Server Virtualization at work – Carlos Garcia Fernandez 14:00 - 14:55 Lecture 3 Unweaving Clouds: Principles and Practice – Belmiro Moreira 15:30 - 16:25 Lecture 4 Understanding Cryptography: From Caesar to Public-Key – Nicola...

  10. Cascaded impedance networks for NPC inverter

    DEFF Research Database (Denmark)

    Li, Ding; Gao, Feng; Loh, Poh Chiang

    2010-01-01

    Multilevel inverters are getting more and more attracted because they have better output waveform quality and lower semiconductor voltage stress. The Z-source NPC is a kind of single stage multilevel inverter which has the ability of voltage boost. But the boost capability is relatively low when...... they are subject to the renewable sources. To date, three distinct types of impedance networks can be summarized for implementing a hybrid source impedance network, which can in principle be combined and cascaded before connected to a NPC inverter by proposed two ways. The resulting cascaded impedance network NPC...... would have a higher output voltage gain. It is anticipated that it would help the formed inverters find applications in photovoltaic and other renewable systems, where a high voltage gain is usually requested. Experimental testing has already been conducted and verifies the theory....

  11. Integrated Inverter For Driving Multiple Electric Machines

    Science.gov (United States)

    Su, Gui-Jia [Knoxville, TN; Hsu, John S [Oak Ridge, TN

    2006-04-04

    An electric machine drive (50) has a plurality of inverters (50a, 50b) for controlling respective electric machines (57, 62), which may include a three-phase main traction machine (57) and two-phase accessory machines (62) in a hybrid or electric vehicle. The drive (50) has a common control section (53, 54) for controlling the plurality of inverters (50a, 50b) with only one microelectronic processor (54) for controlling the plurality of inverters (50a, 50b), only one gate driver circuit (53) for controlling conduction of semiconductor switches (S1-S10) in the plurality of inverters (50a, 50b), and also includes a common dc bus (70), a common dc bus filtering capacitor (C1) and a common dc bus voltage sensor (67). The electric machines (57, 62) may be synchronous machines, induction machines, or PM machines and may be operated in a motoring mode or a generating mode.

  12. Performance analysis of new type grid-tied inverter-Aalborg Inverter

    DEFF Research Database (Denmark)

    Wu, Weimin; Wang, Zhen; Ji, Junhao

    2014-01-01

    Aalborg Inverter is a grid-tied DC/AC inverter. In order to optimize the design, its power losses are analyzed in detail, combined with a description of the single-phase operating principle and the modulation strategy. A 2 kW / 220 V experimental prototype is constructed to verify the theoretical...... analysis. It is concluded that a minimize inductance in the power loop does help the inverter to achieve the high efficiency with the good dynamic performance....

  13. Improvements in ANIS and inverted sputter sources

    Science.gov (United States)

    Strasters, B. A.; Vermeer, A.; van Zwol, N. A.

    1984-02-01

    In this article two sputter sources, i.e. an ANIS and an inverted sputter source are described. The ANIS has been changed into a SNICS-like configuration and measurements of the output current for different sputter target geometries are presented. In the inverted sputter source an immersion lens was placed between the ionizer and the sputter target. This source is provided with a modified revolving target head with eight targets.

  14. Inverted mesiodens--a case report.

    Science.gov (United States)

    Nikhil, S; Vineeta; Gupta, P

    1999-09-01

    A nine and a half years old female school child was examined in a during routine dental examination. The patient had swelling over maxillary midline area just near the labial frenum. Both the central incisors were in position. Radiographic examination revealed presence of an inverted supernumerary tooth between the roots of the central incisors. Surgical extraction of the supernumerary was planned. A unique case of inverted (upside down) mesiodens is presented.

  15. Automatic load sharing in inverter modules

    Science.gov (United States)

    Nagano, S.

    1979-01-01

    Active feedback loads transistor equally with little power loss. Circuit is suitable for balancing modular inverters in spacecraft, computer power supplies, solar-electric power generators, and electric vehicles. Current-balancing circuit senses differences between collector current for power transistor and average value of load currents for all power transistors. Principle is effective not only in fixed duty-cycle inverters but also in converters operating at variable duty cycles.

  16. Base drive for paralleled inverter systems

    Science.gov (United States)

    Nagano, S. (Inventor)

    1980-01-01

    In a paralleled inverter system, a positive feedback current derived from the total current from all of the modules of the inverter system is applied to the base drive of each of the power transistors of all modules, thereby to provide all modules protection against open or short circuit faults occurring in any of the modules, and force equal current sharing among the modules during turn on of the power transistors.

  17. High-performance organic complementary inverters using monolayer graphene electrodes.

    Science.gov (United States)

    Jeong, Yong Jin; Jang, Jaeyoung; Nam, Sooji; Kim, Kyunghun; Kim, Lae Ho; Park, Seonuk; An, Tae Kyu; Park, Chan Eon

    2014-05-14

    Chemical vapor deposition-grown graphene has been an attractive electrode material for organic electronic devices, such as organic field-effect transistors (OFETs), because it is highly conductive and provides good oxidation and thermal stability properties. However, it still remains a challenge to demonstrate organic complementary circuits using graphene electrodes because of the relatively poor performance of n-type OFETs. Here, we report the development of high-performance organic complementary inverters using graphene as source/drain electrodes and N, N'-ditridecyl-3,4,9,10-perylenetetracarboxylic diimide (PTCDI-C13) and pentacene as n- and p-type organic semiconductors, respectively. Graphene electrodes were n-doped via the formation of NH2-terminated self-assembled monolayers that lowered the work function and the electron injection barrier between the graphene and PTCDI-C13. Thermal annealing improved the molecular packing among PTCDI-C13 groups on the graphene surface, thereby increasing the crystallinity and grain size. The thermally annealed PTCDI-C13 OFETs prepared using n-doped graphene electrodes exhibited a good field-effect mobility of up to 0.43 cm2/(V s), which was comparable to the values obtained from other p-type pentacene OFETs. By integrating p- and n-type OFETs, we successfully fabricated organic complementary inverters that exhibited highly symmetric operation with an excellent voltage gain of up to 124 and good noise margin.

  18. Sustained transgene expression despite T lymphocyte responses in a clinical trial of rAAV1-AAT gene therapy.

    Science.gov (United States)

    Brantly, Mark L; Chulay, Jeffrey D; Wang, Lili; Mueller, Christian; Humphries, Margaret; Spencer, L Terry; Rouhani, Farshid; Conlon, Thomas J; Calcedo, Roberto; Betts, Michael R; Spencer, Carolyn; Byrne, Barry J; Wilson, James M; Flotte, Terence R

    2009-09-22

    Alpha-1 antitrypsin (AAT) deficiency is well-suited as a target for human gene transfer. We performed a phase 1, open-label, dose-escalation clinical trial of a recombinant adeno-associated virus (rAAV) vector expressing normal (M) AAT packaged into serotype 1 AAV capsids delivered by i.m. injection. Nine AAT-deficient subjects were enrolled sequentially in cohorts of 3 each at doses of 6.9 x 10(12), 2.2 x 10(13), and 6.0 x 10(13) vector genome particles per patient. Four subjects receiving AAT protein augmentation discontinued therapy 28 or 56 days before vector administration. Vector administration was well tolerated, with only mild local reactions and 1 unrelated serious adverse event (bacterial epididymitis). There were no changes in hematology or clinical chemistry parameters. M-specific AAT was expressed above background in all subjects in cohorts 2 and 3 and was sustained at levels 0.1% of normal for at least 1 year in the highest dosage level cohort, despite development of neutralizing antibody and IFN-gamma enzyme-linked immunospot responses to AAV1 capsid at day 14 in all subjects. These findings suggest that immune responses to AAV capsid that develop after i.m. injection of a serotype 1 rAAV vector expressing AAT do not completely eliminate transduced cells in this context.

  19. AAV-Mediated Gene Targeting Is Significantly Enhanced by Transient Inhibition of Nonhomologous End Joining or the Proteasome In Vivo

    Science.gov (United States)

    Paulk, Nicole K.; Loza, Laura Marquez; Finegold, Milton J.

    2012-01-01

    Abstract Recombinant adeno-associated virus (rAAV) vectors have clear potential for use in gene targeting but low correction efficiencies remain the primary drawback. One approach to enhancing efficiency is a block of undesired repair pathways like nonhomologous end joining (NHEJ) to promote the use of homologous recombination. The natural product vanillin acts as a potent inhibitor of NHEJ by inhibiting DNA-dependent protein kinase (DNA-PK). Using a homology containing rAAV vector, we previously demonstrated in vivo gene repair frequencies of up to 0.1% in a model of liver disease hereditary tyrosinemia type I. To increase targeting frequencies, we administered vanillin in combination with rAAV. Gene targeting frequencies increased up to 10-fold over AAV alone, approaching 1%. Fah−/−Ku70−/− double knockout mice also had increased gene repair frequencies, genetically confirming the beneficial effects of blocking NHEJ. A second strategy, transient proteasomal inhibition, also increased gene-targeting frequencies but was not additive to NHEJ inhibition. This study establishes the benefit of transient NHEJ inhibition with vanillin, or proteasome blockage with bortezomib, for increasing hepatic gene targeting with rAAV. Functional metabolic correction of a clinically relevant disease model was demonstrated and provided evidence for the feasibility of gene targeting as a therapeutic strategy. PMID:22486314

  20. Pharmacological modulation of humoral immunity in a nonhuman primate model of AAV gene transfer for hemophilia B.

    Science.gov (United States)

    Mingozzi, Federico; Chen, Yifeng; Murphy, Samuel L; Edmonson, Shyrie C; Tai, Alex; Price, Sandra D; Metzger, Mark E; Zhou, Shangzhen; Wright, J Fraser; Donahue, Robert E; Dunbar, Cynthia E; High, Katherine A

    2012-07-01

    Liver gene transfer for hemophilia B has shown very promising results in recent clinical studies. A potential complication of gene-based treatments for hemophilia and other inherited disorders, however, is the development of neutralizing antibodies (NAb) against the therapeutic transgene. The risk of developing NAb to the coagulation factor IX (F.IX) transgene product following adeno-associated virus (AAV)-mediated hepatic gene transfer for hemophilia is small but not absent, as formation of inhibitory antibodies to F.IX is observed in experimental animals following liver gene transfer. Thus, strategies to modulate antitransgene NAb responses are needed. Here, we used the anti-B cell monoclonal antibody rituximab (rtx) in combination with cyclosporine A (CsA) to eradicate anti-human F.IX NAb in rhesus macaques previously injected intravenously with AAV8 vectors expressing human F.IX. A short course of immunosuppression (IS) resulted in eradication of anti-F.IX NAb with restoration of plasma F.IX transgene product detection. In one animal, following IS anti-AAV6 antibodies also dropped below detection, allowing for successful AAV vector readministration and resulting in high levels (60% or normal) of F.IX transgene product in plasma. Though the number of animals is small, this study supports for the safety and efficacy of B cell-targeting therapies to eradicate NAb developed following AAV-mediated gene transfer.

  1. CRISPR/Cas9-AAV Mediated Knock-in at NRL Locus in Human Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Xianglian Ge

    2016-01-01

    Full Text Available Clustered interspaced short palindromic repeats (CRISPR/CRISPR-associated protein 9 (Cas9-mediated genome engineering technologies are sparking a new revolution in biological research. This technology efficiently induces DNA double strand breaks at the targeted genomic sequence and results in indel mutations by the error-prone process of nonhomologous end joining DNA repair or homologous recombination with a DNA repair template. The efficiency of genome editing with CRISPR/Cas9 alone in human embryonic stem cells is still low. Gene targeting with adeno-associated virus (AAV vectors has been demonstrated in multiple human cell types with maximal targeting frequencies without engineered nucleases. However, whether CRISPR/Cas9-mediated double strand breaks and AAV based donor DNA mediated homologous recombination approaches could be combined to create a novel CRISPR/Cas9-AAV genetic tool for highly specific gene editing is not clear. Here we demonstrate that using CRISPR/Cas9-AAV, we could successfully knock-in a DsRed reporter gene at the basic motifleucine zipper transcription factor (NRL locus in human embryonic stem cells. For the first time, this study provides the proof of principle that these two technologies can be used together. CRISPR/Cas9-AAV, a new genome editing tool, offers a platform for the manipulation of human genome.

  2. Terminal ballistics

    CERN Document Server

    Rosenberg, Zvi

    2016-01-01

    This book comprehensively discusses essential aspects of terminal ballistics, combining experimental data, numerical simulations and analytical modeling. Employing a unique approach to numerical simulations as a measure of sensitivity for the major physical parameters, the new edition also includes the following features: new figures to better illustrate the problems discussed; improved explanations for the equation of state of a solid and for the cavity expansion process; new data concerning the Kolsky bar test; and a discussion of analytical modeling for the hole diameter in a thin metallic plate impacted by a shaped charge jet. The section on thick concrete targets penetrated by rigid projectiles has now been expanded to include the latest findings, and two new sections have been added: one on a novel approach to the perforation of thin concrete slabs, and one on testing the failure of thin metallic plates using a hydrodynamic ram.

  3. The Neurotropic Properties of AAV-PHP.B Are Limited to C57BL/6J Mice.

    Science.gov (United States)

    Hordeaux, Juliette; Wang, Qiang; Katz, Nathan; Buza, Elizabeth L; Bell, Peter; Wilson, James M

    2018-03-07

    Improved delivery of adeno-associated virus (AAV) vectors to the CNS will greatly enhance their clinical utility. Selection of AAV9 variants in a mouse model led to the isolation of a capsid called PHP.B, which resulted in remarkable transduction of the CNS following intravenous infusion. However, we now show here that this enhanced CNS tropism is restricted to the model in which it was selected, i.e., a Cre transgenic mouse in a C57BL/6J background, and was not found in nonhuman primates or the other commonly used mouse strain BALB/cJ. We also report the potential for serious acute toxicity in NHP after systemic administration of high dose of AAV. Copyright © 2018 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

  4. Differential transgene expression in brain cells in vivo and in vitro from AAV-2 vectors with small transcriptional control units

    International Nuclear Information System (INIS)

    Kuegler, S.; Lingor, P.; Schoell, U.; Zolotukhin, S.; Baehr, M.

    2003-01-01

    Adeno-associated- (AAV) based vectors are promising tools for gene therapy applications in several organs, including the brain, but are limited by their small genome size. Two short promoters, the human synapsin 1 gene promoter (hSYN) and the murine cytomegalovirus immediate early promoter (mCMV), were evaluated in bicistronic AAV-2 vectors for their expression profiles in cultured primary brain cells and in the rat brain. Whereas transgene expression from the hSYN promoter was exclusively neuronal, the murine CMV promoter targeted expression mainly to astrocytes in vitro and showed weak transgene expression in vivo in retinal and cortical neurons, but strong expression in thalamic neurons. We propose that neuron specific transgene expression in combination with enhanced transgene capacity will further substantially improve AAV based vector technology

  5. DNA structure modulates the oligomerization properties of the AAV initiator protein Rep68.

    Directory of Open Access Journals (Sweden)

    Jorge Mansilla-Soto

    2009-07-01

    Full Text Available Rep68 is a multifunctional protein of the adeno-associated virus (AAV, a parvovirus that is mostly known for its promise as a gene therapy vector. In addition to its role as initiator in viral DNA replication, Rep68 is essential for site-specific integration of the AAV genome into human chromosome 19. Rep68 is a member of the superfamily 3 (SF3 helicases, along with the well-studied initiator proteins simian virus 40 large T antigen (SV40-LTag and bovine papillomavirus (BPV E1. Structurally, SF3 helicases share two domains, a DNA origin interaction domain (OID and an AAA(+ motor domain. The AAA(+ motor domain is also a structural feature of cellular initiators and it functions as a platform for initiator oligomerization. Here, we studied Rep68 oligomerization in vitro in the presence of different DNA substrates using a variety of biophysical techniques and cryo-EM. We found that a dsDNA region of the AAV origin promotes the formation of a complex containing five Rep68 subunits. Interestingly, non-specific ssDNA promotes the formation of a double-ring Rep68, a known structure formed by the LTag and E1 initiator proteins. The Rep68 ring symmetry is 8-fold, thus differing from the hexameric rings formed by the other SF3 helicases. However, similiar to LTag and E1, Rep68 rings are oriented head-to-head, suggesting that DNA unwinding by the complex proceeds bidirectionally. This novel Rep68 quaternary structure requires both the DNA binding and AAA(+ domains, indicating cooperativity between these regions during oligomerization in vitro. Our study clearly demonstrates that Rep68 can oligomerize through two distinct oligomerization pathways, which depend on both the DNA structure and cooperativity of Rep68 domains. These findings provide insight into the dynamics and oligomeric adaptability of Rep68 and serve as a step towards understanding the role of this multifunctional protein during AAV DNA replication and site-specific integration.

  6. Supramolecular polypseudorotaxane gels for controlled delivery of rAAV vectors in human mesenchymal stem cells for regenerative medicine.

    Science.gov (United States)

    Rey-Rico, Ana; Babicz, Heiko; Madry, Henning; Concheiro, Angel; Alvarez-Lorenzo, Carmen; Cucchiarini, Magali

    2017-10-15

    The aim of this work was to investigate, for the first time, the possibility of using supramolecular polypseudorotaxane gels as scaffolds that can durably deliver rAAV vectors for applications in cartilage regeneration. Dispersions of Pluronic ® F68 (PF68) or Tetronic ® 908 (T908) containing either hyaluronic acid (HA) or chondroitin sulfate (CS) were prepared in PBS. Then, alpha-cyclodextrin (αCD) was added to some dispersions to form polypseudorotaxane gels. Polysaccharides and αCD reinforced the viscoelasticity of the gels, which could withstand autoclaving without changes. In vitro release of rAAV vectors and subsequent transduction of human mesenchymal stem cells (hMSCs) by rAAV vectors from the release medium and from gels in direct contact with the cells were investigated. Compared with free vectors, the gels provided higher levels of transgene expression. CS (or HA)/PF68/αCD gels rapidly released rAAV vectors while CS (or HA)/T908/αCD gels provided sustained release probably due to different interactions with the viral vectors. Incorporation of αCD into CS (or HA)/PF68 gels resulted on higher rAAV concentrations and sustained levels of transgene expression over time. HA increased the bioactivity and cytocompatibility of the gels, especially those based on T908. Overall, combining rAAV gene transfer with polypseudorotaxane gels may provide new, promising tools for human tissue engineering and regenerative medicine strategies. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Targeted genetic manipulations of neuronal subtypes using promoter-specific combinatorial AAVs in wild-type animals

    Science.gov (United States)

    Gompf, Heinrich S.; Budygin, Evgeny A.; Fuller, Patrick M.; Bass, Caroline E.

    2015-01-01

    Techniques to genetically manipulate the activity of defined neuronal subpopulations have been useful in elucidating function, however applicability to translational research beyond transgenic mice is limited. Subtype targeted transgene expression can be achieved using specific promoters, but often currently available promoters are either too large to package into many vectors, in particular adeno-associated virus (AAV), or do not drive expression at levels sufficient to alter behavior. To permit neuron subtype specific gene expression in wildtype animals, we developed a combinatorial AAV targeting system that drives, in combination, subtype specific Cre-recombinase expression with a strong but non-specific Cre-conditional transgene. Using this system we demonstrate that the tyrosine hydroxylase promoter (TH-Cre-AAV) restricted expression of channelrhodopsin-2 (EF1α-DIO-ChR2-EYFP-AAV) to the rat ventral tegmental area (VTA), or an activating DREADD (hSyn-DIO-hM3Dq-mCherry-AAV) to  the  rat  locus  coeruleus  (LC). High expression levels were achieved in both regions. Immunohistochemistry (IHC) showed the majority of ChR2+ neurons (>93%) colocalized with TH in the VTA, and optical stimulation evoked striatal dopamine release. Activation of TH neurons in the LC produced sustained EEG and behavioral arousal. TH-specific hM3Dq expression in the LC was further compared with: (1) a Cre construct driven by a strong but non-specific promoter (non-targeting); and (2) a retrogradely-transported WGA-Cre delivery mechanism (targeting a specific projection). IHC revealed that the area of c-fos activation after CNO treatment in the LC and peri-LC neurons appeared proportional to the resulting increase in wakefulness (non-targeted > targeted > ACC to LC projection restricted). Our dual AAV targeting system effectively overcomes the large size and weak activity barrier prevalent with many subtype specific promoters by functionally separating subtype specificity from

  8. Effect Of DNA-dependent protein kinase on the molecular fate of the rAAV2 genome in skeletal muscle

    Science.gov (United States)

    Song, Sihong; Laipis, Philip J.; Berns, Kenneth I.; Flotte, Terence R.

    2001-01-01

    We report here that the DNA-dependent protein kinase (DNA-PK) affects the molecular fate of the recombinant adeno-associated virus (rAAV) genome in skeletal muscle. rAAV-human α1-antitrypsin (rAAV-hAAT) vectors were delivered by intramuscular injection to either C57BL/6 (DNA-PKcs+) or C57BL/6-SCID [severe combined immunodeficient (SCID), DNA-PKcs−] mice. In both strains, high levels of transgene expression were sustained for up to 1 year after a single injection. Southern blot analysis showed that rAAV genomes persisted as linear episomes for more than 1 year in SCID mice, whereas only circular episomal forms were observed in the C57BL/6 strain. These results indicate that DNA-PK is involved in the formation of circular rAAV episomes. PMID:11274433

  9. Termination unit

    Science.gov (United States)

    Traeholt, Chresten [Frederiksberg, DK; Willen, Dag [Klagshamn, SE; Roden, Mark [Newnan, GA; Tolbert, Jerry C [Carrollton, GA; Lindsay, David [Carrollton, GA; Fisher, Paul W [Heiskell, TN; Nielsen, Carsten Thidemann [Jaegerspris, DK

    2014-01-07

    This invention relates to a termination unit comprising an end-section of a cable. The end section of the cable defines a central longitudinal axis and comprising end-parts of N electrical phases, an end-part of a neutral conductor and a surrounding thermally insulation envelope adapted to comprising a cooling fluid. The end-parts of the N electrical phases and the end-part of the neutral conductor each comprising at least one electrical conductor and being arranged in the cable concentrically around a core former with a phase 1 located relatively innermost, and phase N relatively outermost in the cable, phase N being surrounded by the neutral conductor, electrical insulation being arrange between neighboring electrical phases and between phase N and the neutral conductor, and wherein the end-parts of the neutral conductor and the electrical phases each comprise a contacting surface electrically connected to at least one branch current lead to provide an electrical connection: The contacting surfaces each having a longitudinal extension, and being located sequentially along the longitudinal extension of the end-section of the cable. The branch current leads being individually insulated from said thermally insulation envelope by individual electrical insulators.

  10. Inverter for Installations with Intermittent Electricity Production

    Directory of Open Access Journals (Sweden)

    Ermuraki Iu.

    2016-04-01

    Full Text Available A new architecture of the inverter used in the convertion of electric energy generated by renewable energy sources is studied in this paper. The distinctive features of this inverter is the special block which compensates pulsing of the current with double frequency, characteristic for these inverters. The switching of electronic keys is realized using the method TCM In this block, like in the inverter, which assures the switching at the voltages near to zero (ZVC. The proposed algorithm of controlling the electronic keys permits to increase the work frequency up to hundreds of kHz. Electronic keys operate at variable frequency, which changes during the work cycle both slowly and by jump. The assurance of admissible heat regime is performed using forced cooling air flux and by convection. The increase of releasing process of the heat is assured by original construction of radiators which forms the turbulent mode of cooling air flux. These changes of the architecture of the inverter have allowed the minimization of mass, sizes and price indicators. It has been manufactured a functional laboratory sample with output power of 2kW the voltage of direct current of 450V or 48 V and output alternating voltage of 230V, with sizes 175mmX35mmX30mm.

  11. Addressable inverter matrix for process and device characterization

    Science.gov (United States)

    Buehler, M. G.; Sayah, H. R.

    1985-01-01

    The addressable inverter matrix consists of 222 inverters each accessible with the aid of a shift register. The structure has proven useful in characterizing the variability of inverter transfer curves and in diagnosing processing faults. For good 3-micron CMOS bulk inverters investigated, the percent standard deviation of the inverter threshold voltage was less than one percent and the inverter gain (the slope of the inverter transfer curve at the inverter threshold vltage) was less than 3 percent. The average noise margin for the inverters was near 2 volts for a power supply voltage of 5 volts. The specific faults studied included undersize pull-down transistor widths and various open contacts in the matrix.

  12. Power inverter implementing phase skipping control

    Science.gov (United States)

    Somani, Utsav; Amirahmadi, Ahmadreza; Jourdan, Charles; Batarseh, Issa

    2016-10-18

    A power inverter includes a DC/AC inverter having first, second and third phase circuitry coupled to receive power from a power source. A controller is coupled to a driver for each of the first, second and third phase circuitry (control input drivers). The controller includes an associated memory storing a phase skipping control algorithm, wherein the controller is coupled to receive updating information including a power level generated by the power source. The drivers are coupled to control inputs of the first, second and third phase circuitry, where the drivers are configured for receiving phase skipping control signals from the controller and outputting mode selection signals configured to dynamically select an operating mode for the DC/AC inverter from a Normal Control operation and a Phase Skipping Control operation which have different power injection patterns through the first, second and third phase circuitry depending upon the power level.

  13. Radiological follow-up of inverted papilloma

    Energy Technology Data Exchange (ETDEWEB)

    Petit, P.; Vivarrat-Perrin, L.; Champsaur, P.; Juhan, V.; Chagnaud, C.; Vidal, V.; Gaubert, J.Y.; Bartoli, J.M.; Moulin, G. [Department of Radiology, Groupe Hospitalier de la Timone, Centre Hospitalier et Universitaire de Marseille, F-13385 Marseille Cedex 5 (France); Dessi, P.; Zanaret, M. [Department of Head and Neck Surgery, Groupe Hospitalier de la Timone, Centre Hospitalier et Universitaire de Marseille, F-13385 Marseille Cedex 5 (France)

    2000-07-01

    The aim of this study was to describe cross-sectional imaging features of recurrent papilloma of the nasal fossa and paranasal sinuses and to evaluate the role of MR and CT in the postoperative follow-up of this lesion. Magnetic resonance imaging and CT of ten patients who presented recurrence of inverted papilloma were reviewed and correlated to initial imaging, endoscopy, and surgical reports. Imaging patterns of recurrent inverted papilloma are identical to those of initial tumors and recurrence location is closely related to the site of the former lesion. Magnetic resonance is more efficient than CT for the diagnosis and evaluation of extensions. Magnetic resonance supplies the deficiencies of endoscopy in case of extensions to the frontal sinus or the lateral recess of the antrum, especially if mucosal hyperplasia or sinusitis is associated. Magnetic resonance imaging is the first imaging modality to perform in the follow-up after removal of inverted papilloma. (orig.)

  14. An SCR inverter for electric vehicles

    Science.gov (United States)

    Latos, T.; Bosack, D.; Ehrlich, R.; Jahns, T.; Mezera, J.; Thimmesch, D.

    1980-01-01

    An inverter for an electric vehicle propulsion application has been designed and constructed to excite a polyphase induction motor from a fixed propulsion battery source. The inverter, rated at 35kW peak power, is fully regenerative and permits vehicle operation in both the forward and reverse directions. Thyristors are employed as the power switching devices arranged in a dc bus commutated topology. This paper describes the major role the controller plays in generating the motor excitation voltage and frequency to deliver performance similar to dc systems. Motoring efficiency test data for the controller are presented. It is concluded that an SCR inverter in conjunction with an ac induction motor is a viable alternative to present dc vehicle propulsion systems on the basis of performance and size criteria.

  15. Prediction of Transcriptional Terminators in Bacillus subtilis and Related Species.

    Directory of Open Access Journals (Sweden)

    2005-08-01

    Full Text Available In prokaryotes, genes belonging to the same operon are transcribed in a single mRNA molecule. Transcription starts as the RNA polymerase binds to the promoter and continues until it reaches a transcriptional terminator. Some terminators rely on the presence of the Rho protein, whereas others function independently of Rho. Such Rho-independent terminators consist of an inverted repeat followed by a stretch of thymine residues, allowing us to predict their presence directly from the DNA sequence. Unlike in Escherichia coli, the Rho protein is dispensable in Bacillus subtilis, suggesting a limited role for Rho-dependent termination in this organism and possibly in other Firmicutes. We analyzed 463 experimentally known terminating sequences in B. subtilis and found a decision rule to distinguish Rho-independent transcriptional terminators from non-terminating sequences. The decision rule allowed us to find the boundaries of operons in B. subtilis with a sensitivity and specificity of about 94%. Using the same decision rule, we found an average sensitivity of 94% for 57 bacteria belonging to the Firmicutes phylum, and a considerably lower sensitivity for other bacteria. Our analysis shows that Rho-independent termination is dominant for Firmicutes in general, and that the properties of the transcriptional terminators are conserved. Terminator prediction can be used to reliably predict the operon structure in these organisms, even in the absence of experimentally known operons. Genome-wide predictions of Rho-independent terminators for the 57 Firmicutes are available in the Supporting Information section.

  16. Smart Inverters for Utility and Industry Applications

    DEFF Research Database (Denmark)

    Xue, Yaosuo; Guerrero, Josep M.

    2015-01-01

    Smart inverters are emerging with increasing renewable energy and smart grid development. While the recent work reviewed mostly focuses on defining standardized control functionalities and smart grid communication protocols, we take a holistic approach in this paper and propose a holon-type smart...... inverter concept, which features autonomous, adaptive, cooperative and plug-and-play functions. Self-awareness is also continually driven by power electronics inherently. These features can be favorable in a complex environment with more and more small-scale power electronics-based devices, and can reduce...

  17. Asymmetrical transformer-based embedded Z-source inverters

    DEFF Research Database (Denmark)

    Wei, Mo; Loh, Poh Chiang; Blaabjerg, Frede

    2013-01-01

    Z-source inverters are inverters with buck-boost capability that traditional inverters cannot match. Despite this ability, present Z-source topologies are burdened by some limitations such as chopping input current, high-voltage stress and poor spectral performance at high gain. To improve...... their performances, a number of asymmetrical transformer-based embedded Z-source inverters are proposed. Through theoretical derivation and experiments, the proposed inverters have been shown to draw a smooth input current and produce a high gain by varying the transformer turns ratio n. The range of variation for n...... depends on the inverter topology chosen, which in turn depends on the application under consideration....

  18. Characteristics Comparison of High-Frequency Multi-Level Inverter Connected with Filter Inverters

    Science.gov (United States)

    Iwaya, Kazuki; Noguchi, Toshihiko

    This paper presents characteristics comparison of a high-frequency multi-level inverter connected with small capacity filter inverters. In general, PWM inverters require a low-pass filter in order to reduce switching harmonics. However, in the high-frequency systems such as class D power amplifiers, the cut-off frequency of the low-pass filter must set at high frequency. Thus, harmonic distortion of the output voltage harmfully enlarges. Increasing the number of output voltage levels is effective to reduce the harmonic distortion of the output voltage and the low-pass filter size. The proposed systems consist of a 5-level inverter and several cascade-connected low-voltage full bridge inverters without any external DC power sources for filtering the output voltage. The 5-level inverter generates a stepwise waveform with 5-level voltage, and the low voltage filter inverter superimposes harmonic components to compensate for the voltage waveform distortion. Therefore, the proposed system can reduce its total switching loss and can increase the number of the output voltage levels. In this paper, effectiveness of the proposed systems is verified through several experiments.

  19. Design of Solar PV Cell Based Inverter for Unbalanced and Distorted Industrial Loads

    Directory of Open Access Journals (Sweden)

    Naga Ananth D

    2015-04-01

    Full Text Available PV cell is getting importance in low and medium power generation due to easy installation, low maintenance and subsidies in price from respective nation. Most of the loads in distribution system are unbalanced and distorted, due to which there will be unbalanced voltage and current occur at load and may disturb its overall performance. Due to these loads voltage unbalance, distorted voltage and current and variable power factors in each phase can be observed. An efficient algorithm to mitigate unbalanced and distorted load and source voltage and current in solar photo voltaic (PV inverter for isolated load system was considered. This solar PV system can be applicable to remote located industrial loads like heating, welding and small arc furnace type distorted loads and also for unbalanced loads. The PV inverter is designed such that it will maintain nearly constant voltage magnitude and can mitigate harmonics in voltage and current near the load terminals. A MATLAB/ SIMULINK based solar PV inverter was simulated and results are compared with standard AC three phase grid connected system. The proposed shows that the inverter is having very less voltage and current harmonic content and can maintain nearly constant voltage profile for highly unbalanced system.

  20. Safety and Biodistribution Evaluation in Cynomolgus Macaques of rAAV2tYF-PR1.7-hCNGB3, a Recombinant AAV Vector for Treatment of Achromatopsia.

    Science.gov (United States)

    Ye, Guo-jie; Budzynski, Ewa; Sonnentag, Peter; Nork, T Michael; Miller, Paul E; Sharma, Alok K; Ver Hoeve, James N; Smith, Leia M; Arndt, Tara; Calcedo, Roberto; Gaskin, Chantelle; Robinson, Paulette M; Knop, David R; Hauswirth, William W; Chulay, Jeffrey D

    2016-03-01

    Applied Genetic Technologies Corporation (AGTC) is developing rAAV2tYF-PR1.7-hCNGB3, a recombinant adeno-associated viral (rAAV) vector expressing the human CNGB3 gene, for treatment of achromatopsia, an inherited retinal disorder characterized by markedly reduced visual acuity, extreme light sensitivity, and absence of color discrimination. We report here results of a study evaluating the safety and biodistribution of rAAV2tYF-PR1.7-hCNGB3 in cynomolgus macaques. Three groups of animals (n = 2 males and 2 females per group) received a subretinal injection in one eye of 300 μl containing either vehicle or rAAV2tYF-PR1.7-hCNGB3 at one of two concentrations (4 × 10(11) or 4 × 10(12) vector genomes/ml) and were evaluated over a 3-month period before being euthanized. Administration of rAAV2tYF-PR1.7-hCNGB3 was associated with a dose-related anterior and posterior segment inflammatory response that was greater than that observed in eyes injected with the vehicle control. Most manifestations of inflammation improved over time except that vitreous cells persisted in vector-treated eyes until the end of the study. One animal in the lower vector dose group was euthanized on study day 5, based on a clinical diagnosis of endophthalmitis. There were no test article-related effects on intraocular pressure, visual evoked potential responses, hematology or clinical chemistry parameters, or gross necropsy observations. Histopathological examination demonstrated minimal mononuclear infiltrates in all vector-injected eyes. Serum anti-AAV antibodies developed in all vector-injected animals. No animals developed antibodies to CNGB3. Biodistribution studies demonstrated high levels of vector DNA in the injected eye but minimal or no vector DNA in any other tissue. These results support the use of rAAV2tYF-PR1.7-hCNGB3 in clinical studies in patients with achromatopsia caused by CNGB3 mutations.

  1. Live Imaging of Shoot Meristems on an Inverted Confocal Microscope Using an Objective Lens Inverter Attachment.

    Science.gov (United States)

    Nimchuk, Zachary L; Perdue, Tony D

    2017-01-01

    Live imaging of above ground meristems can lead to new insights in plant development not possible from static imaging of fixed tissue. The use of an upright confocal microscope offers several technical and biological advantages for live imaging floral or shoot meristems. However, many departments and core facilities possess only inverted confocal microscopes and lack the funding for an additional upright confocal microscope. Here we show that imaging of living apical meristems can be performed on existing inverted confocal microscopes with the use of an affordable and detachable InverterScope accessory.

  2. High voltage series resonant inverter ion engine screen supply. [SCR series resonant inverter for space applications

    Science.gov (United States)

    Biess, J. J.; Inouye, L. Y.; Shank, J. H.

    1974-01-01

    A high-voltage, high-power LC series resonant inverter using SCRs has been developed for an Ion Engine Power Processor. The inverter operates within 200-400Vdc with a maximum output power of 2.5kW. The inverter control logic, the screen supply electrical and mechanical characteristics, the efficiency and losses in power components, regulation on the dual feedback principle, the SCR waveforms and the component weight are analyzed. Efficiency of 90.5% and weight density of 4.1kg/kW are obtained.

  3. AAV-mediated expression of CNTF promotes long-term survival and regeneration of adult rat retinal ganglion cells

    NARCIS (Netherlands)

    Leaver, Simone G; Cui, Qi; Plant, Giles W; Arulpragasam, A.; Hisheh, S; Verhaagen, J; Harvey, Alan R

    We compared the effects of intravitreal injection of bi-cistronic adeno-associated viral (AAV-2) vectors encoding enhanced green fluorescent protein (GFP) and either ciliary neurotrophic factor (CNTF), brain-derived neurotrophic factor (BDNF) or growth-associated protein-43 (GAP43) on adult retinal

  4. Long-term, efficient inhibition of microRNA function in mice using rAAV vectors.

    Science.gov (United States)

    Xie, Jun; Ameres, Stefan L; Friedline, Randall; Hung, Jui-Hung; Zhang, Yu; Xie, Qing; Zhong, Li; Su, Qin; He, Ran; Li, Mengxin; Li, Huapeng; Mu, Xin; Zhang, Hongwei; Broderick, Jennifer A; Kim, Jason K; Weng, Zhiping; Flotte, Terence R; Zamore, Phillip D; Gao, Guangping

    2012-03-04

    Understanding the function of individual microRNA (miRNA) species in mice would require the production of hundreds of loss-of-function strains. To accelerate analysis of miRNA biology in mammals, we combined recombinant adeno-associated virus (rAAV) vectors with miRNA 'tough decoys' (TuDs) to inhibit specific miRNAs. Intravenous injection of rAAV9 expressing anti-miR-122 or anti-let-7 TuDs depleted the corresponding miRNA and increased its mRNA targets. rAAV producing anti-miR-122 TuD but not anti-let-7 TuD reduced serum cholesterol by >30% for 25 weeks in wild-type mice. High-throughput sequencing of liver miRNAs from the treated mice confirmed that the targeted miRNAs were depleted and revealed that TuDs induced miRNA tailing and trimming in vivo. rAAV-mediated miRNA inhibition thus provides a simple way to study miRNA function in adult mammals and a potential therapy for dyslipidemia and other diseases caused by miRNA deregulation.

  5. Progressive neurodegenerative and behavioural changes induced by AAV-mediated overexpression of α-synuclein in midbrain dopamine neurons

    DEFF Research Database (Denmark)

    Decressac, M; Mattsson, Bente; Lundblad, M

    2012-01-01

    have failed to show a consistent behavioural phenotype and pronounced dopamine neurodegeneration. Using a more efficient adeno-associated viral (AAV) vector construct, which includes a WPRE enhancer element and uses the neuron-specific synapsin-1 promoter to drive the expression of human wild-type α...

  6. An AAV promoter-driven neuropeptide Y gene delivery system using Sendai virosomes for neurons and rat brain.

    Science.gov (United States)

    Wu, P; de Fiebre, C M; Millard, W J; King, M A; Wang, S; Bryant, S O; Gao, Y P; Martin, E J; Meyer, E M

    1996-03-01

    An adeno-associated virus (AAV)-derived construct (pJDT95npy) containing rat neuropeptide Y (NPY) cDNA inserted downstream of endogenous AAV promoters was used to investigate AAV-driven NPY expression in postmitotic neurons in vitro and in the brain. NPY mRNA was expressed in NT2/N and rat brain primary neuronal cultures after transfection. There was a corresponding increase in the number of neurons staining for NPY-like immunoreactivity and an increase in NPY release during depolarization in the primary cultures. Injections of Sendai-virosome encapsulated pJDT95npy into neocortex increased NPY-like immunoreactivity in neurons but not glia indicating that the latter cell type did not have the translational, post-translational or storage capacity to accumulate the peptide. Injections into the rat hypothalamic para-ventricular nucleus increased body weight and food intake for 21 days, though NPY-like immunoreactivity remained elevated for at least 50 days. These studies demonstrate that AAV-derived constructs may be useful for delivering genes into post-mitotic neurons, and that Sendai virosomes are effective for delivering these constructs in vivo.

  7. Inverted Pedagogy in Second Semester Calculus

    Science.gov (United States)

    Kennedy, Ellie; Beaudrie, Brian; Ernst, Dana C.; St. Laurent, Roy

    2015-01-01

    This study investigates the effects of applying an inverted classroom model in a second-semester calculus course at a large regional university in the southwest during the Spring of 2013. The sample consisted of four class sections with the same instructor, with a total of 173 students; two class sections were in the experimental group, whereas…

  8. Inverting the Transition-to-Proof Classroom

    Science.gov (United States)

    Talbert, Robert

    2015-01-01

    In this paper, we examine the benefits of employing an inverted or "flipped" class design in a Transition-to-Proof course for second-year mathematics majors. The issues concomitant with such courses, particularly student acquisition of "sociomathematical norms" and self-regulated learning strategies, are discussed along with…

  9. MPPT algorithm for voltage controlled PV inverters

    DEFF Research Database (Denmark)

    Kerekes, Tamas; Teodorescu, Remus; Liserre, Marco

    2008-01-01

    This paper presents a novel concept for an MPPT that can be used in case of a voltage controlled grid connected PV inverters. In case of single-phase systems, the 100 Hz ripple in the AC power is also present on the DC side. Depending on the DC link capacitor, this power fluctuation can be used...

  10. The Internet and the Inverted Classroom.

    Science.gov (United States)

    Lage, Maureen J.; Platt, Glenn

    2000-01-01

    Describes a Web site that is for an undergraduate principles of microeconomics course and a main component of "The Inverted Classroom" in which lectures take place outside of class. Explains that the Web site is divided into four sections: (1) the classroom; (2) the desk; (3) the coffee shop; and (4) the library. (CMK)

  11. Solar Power Station Output Inverter Control Design

    Directory of Open Access Journals (Sweden)

    J. Bauer

    2011-04-01

    Full Text Available The photovoltaic applications spreads in these days fast, therefore they also undergo great development. Because the amount of the energy obtained from the panel depends on the surrounding conditions, as intensity of the sun exposure or the temperature of the solar array, the converter must be connected to the panel output. The Solar system equipped with inverter can supply small loads like notebooks, mobile chargers etc. in the places where the supplying network is not present. Or the system can be used as a generator and it shall deliver energy to the supply network. Each type of the application has different requirements on the converter and its control algorithm. But for all of them the one thing is common – the maximal efficiency. The paper focuses on design and simulation of the low power inverter that acts as output part of the whole converter. In the paper the design of the control algorithm of the inverter for both types of inverter application – for islanding mode and for operation on the supply grid – is discussed. Attention is also paid to the design of the output filter that should reduce negative side effects of the converter on the supply network.

  12. Subintegrality, invertible modules and Laurent polynomial extensions

    Indian Academy of Sciences (India)

    Indian Acad. Sci. (Math. Sci.) Vol. 125, No. 2, May 2015, pp. 149–160. c Indian Academy of Sciences. Subintegrality, invertible modules and Laurent polynomial extensions. VIVEK SADHU. Department of Mathematics ...... comments which have improved the exposition. Further, he would like to thank CSIR,. India for financial ...

  13. Two-Stage Series-Resonant Inverter

    Science.gov (United States)

    Stuart, Thomas A.

    1994-01-01

    Two-stage inverter includes variable-frequency, voltage-regulating first stage and fixed-frequency second stage. Lightweight circuit provides regulated power and is invulnerable to output short circuits. Does not require large capacitor across ac bus, like parallel resonant designs. Particularly suitable for use in ac-power-distribution system of aircraft.

  14. Inverter Matrix for the Clementine Mission

    Science.gov (United States)

    Buehler, M. G.; Blaes, B. R.; Tardio, G.; Soli, G. A.

    1994-01-01

    An inverter matrix test circuit was designed for the Clementine space mission and is built into the RRELAX (Radiation and Reliability Assurance Experiment). The objective is to develop a circuit that will allow the evaluation of the CMOS FETs using a lean data set in the noisy spacecraft environment.

  15. Pulse width modulation inverter with battery charger

    Science.gov (United States)

    Slicker, James M. (Inventor)

    1985-01-01

    An inverter is connected between a source of DC power and a three-phase AC induction motor, and a microprocessor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .theta., where .theta. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands for electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a flyback DC-DC converter circuit for recharging the battery.

  16. The invertible double of elliptic operators

    DEFF Research Database (Denmark)

    Booss-Bavnbek, Bernhelm; Lesch, Matthias; Zhu, Chaofeng

    We construct a canonical invertible double for general first order elliptic differential operators over smooth compact manifolds with boundary and derive a natural formula for the Calderon projector which yields a generalization of the famous Cobordism Theorem. Assuming symmetric principal symbol...

  17. rAAV9 combined with renal vein injection is optimal for kidney-targeted gene delivery: conclusion of a comparative study.

    Science.gov (United States)

    Rocca, C J; Ur, S N; Harrison, F; Cherqui, S

    2014-06-01

    Effective gene therapy strategies for the treatment of kidney disorders remain elusive. We report an optimized kidney-targeted gene delivery strategy using recombinant adeno-associated virus (rAAV) administered via retrograde renal vein injection in mice. Renal vein injection of rAAV consistently resulted in superior kidney transduction compared with tail vein injection using as little as half the tail vein dose. We compared rAAV5, 6, 8 and 9, containing either green fluorescent protein (GFP) or luciferase reporter genes driven by the Cytomegalovirus promoter. We demonstrated that although rAAV6 and 8 injected via renal vein transduced the kidney, transgene expression was mainly restricted to the medulla. Transgene expression was systematically low after rAAV5 injection, attributed to T-cell immune response, which could be overcome by transient immunosuppression. However, rAAV9 was the only serotype that permitted high-transduction efficiency of both the cortex and medulla. Moreover, both the glomeruli and tubules were targeted, with a higher efficiency within the glomeruli. To improve the specificity of kidney-targeted gene delivery with rAAV9, we used the parathyroid hormone receptor 'kidney-specific' promoter. We obtained a more efficient transgene expression within the kidney, and a significant reduction in other tissues. Our work represents the first comprehensive and clinically relevant study for kidney gene delivery.

  18. Synergistic inhibition of PARP-1 and NF-κB signaling downregulates immune response against recombinant AAV2 vectors during hepatic gene therapy.

    Science.gov (United States)

    Hareendran, Sangeetha; Ramakrishna, Banumathi; Jayandharan, Giridhara R

    2016-01-01

    Host immune response remains a key obstacle to widespread application of adeno-associated virus (AAV) based gene therapy. Thus, targeted inhibition of the signaling pathways that trigger such immune responses will be beneficial. Previous studies have reported that DNA damage response proteins such as poly(ADP-ribose) polymerase-1 (PARP-1) negatively affect the integration of AAV in the host genome. However, the role of PARP-1 in regulating AAV transduction and the immune response against these vectors has not been elucidated. In this study, we demonstrate that repression of PARP-1 improves the transduction of single-stranded AAV vectors both in vitro (∼174%) and in vivo (two- to 3.4-fold). Inhibition of PARP-1, also significantly downregulated the expression of several proinflammatory and cytokine markers such as TLRs, ILs, NF-κB subunit proteins associated with the host innate response against self-complementary AAV2 vectors. The suppression of the inflammatory response targeted against these vectors was more effective upon combined inhibition of PARP-1 and NF-κB signaling. This strategy also effectively attenuated the AAV capsid-specific cytotoxic T-cell response, with minimal effect on vector transduction, as demonstrated in normal C57BL/6 and hemophilia B mice. These data suggest that targeting specific host cellular proteins could be useful to attenuate the immune barriers to AAV-mediated gene therapy. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. LIGHT induces distinct signals to clear an AAV-expressed persistent antigen in the mouse liver and to induce liver inflammation.

    Directory of Open Access Journals (Sweden)

    Michael L Washburn

    2010-05-01

    Full Text Available Infection with adeno-associated virus (AAV vector with liver tropism leads to persistent expression of foreign antigens in the mouse liver, with no significant liver inflammation or pathology. This provides a model to investigate antigen persistence in the liver and strategies to modulate host immunity to reduce or clear the foreign antigen expressed from AAV vector in the liver.We showed that expressing LIGHT with an adenovirus vector (Ad in mice with established AAV in the liver led to clearance of the AAV. Ad-LIGHT enhanced CD8 effector T cells in the liver, correlated with liver inflammation. LTbetaR-Ig proteins blocked Ad-LIGHT in clearing AAV. Interestingly, in LTbetaR-null mice, Ad-LIGHT still cleared AAV but caused no significant liver inflammation.Our data suggest that LIGHT interaction with the LTbetaR plays a critical role in liver inflammation but is not required for LIGHT-mediated AAV clearance. These findings will shed light on developing novel immuno-therapeutics in treating people chronically infected with hepato-tropic viruses.

  20. Site-specific integration of CAR gene into Jurkat T cells with a linear close-ended AAV-based DNA vector for CAR-T engineering.

    Science.gov (United States)

    Zhang, Yun; Liu, Xiaomei; Zhang, Jinju; Zhang, Chun

    2016-09-01

    To develop a site-specific integration strategy for CAR-T engineering by using a non-viral vector dependent on adeno-associated viral (AAV) genome, which tends to be integrated into AAVS1 site with the help of its Rep proteins. AAV-dependent vectors were produced in Sf9 cells. Structural analyses revealed the vector as covalently close-ended, linear duplex molecules, which was termed "CELiD" DNA. A plasmid CMV-Rep was constructed to express the integrases Rep78 and Rep68. Jurkat cells were co-electroporated with "CELiD" DNA and plasmid CMV-Rep in order to specifically integrate CAR gene into AAVS1 site. We examined 71 stably transfected Jurkat clones by nested PCR, sequencing and southern blotting, of which 30 clones bore CAR gene within AAVS1 site. The site-specific integration efficiency was nearly 42.2 %. The AAV-dependent vector preferentially integrated CAR into AAVS1 site, which could be further used in human T cell modification and enhance the security of CAR-T therapy.

  1. Coal terminal developments

    Energy Technology Data Exchange (ETDEWEB)

    Venter, J.

    2008-02-15

    The article reports developments at many coal terminals worldwide. These include Bulgaria's Port of Bourgas Temrinal 2A, Spain's Tarragona Port Services (TPS) terminal, New Zealand's Lyttleton Port of Christchurch (LPC), Kinder Morgan's terminals in the USA (the International Marine terminal, Cora terminal, Grand Rivers terminal and Fairless Hills terminal) and Croatia's Port of Ploce. Developments at coal terminals in France and Belgium are also summarized. Global transportation services offered by Rhenus are described. 12 photos.

  2. Novel rat Alzheimer's disease models based on AAV-mediated gene transfer to selectively increase hippocampal Aβ levels

    Directory of Open Access Journals (Sweden)

    Dicker Bridget L

    2007-06-01

    Full Text Available Abstract Background Alzheimer's disease (AD is characterized by a decline in cognitive function and accumulation of amyloid-β peptide (Aβ in extracellular plaques. Mutations in amyloid precursor protein (APP and presenilins alter APP metabolism resulting in accumulation of Aβ42, a peptide essential for the formation of amyloid deposits and proposed to initiate the cascade leading to AD. However, the role of Aβ40, the more prevalent Aβ peptide secreted by cells and a major component of cerebral Aβ deposits, is less clear. In this study, virally-mediated gene transfer was used to selectively increase hippocampal levels of human Aβ42 and Aβ40 in adult Wistar rats, allowing examination of the contribution of each to the cognitive deficits and pathology seen in AD. Results Adeno-associated viral (AAV vectors encoding BRI-Aβ cDNAs were generated resulting in high-level hippocampal expression and secretion of the specific encoded Aβ peptide. As a comparison the effect of AAV-mediated overexpression of APPsw was also examined. Animals were tested for development of learning and memory deficits (open field, Morris water maze, passive avoidance, novel object recognition three months after infusion of AAV. A range of impairments was found, with the most pronounced deficits observed in animals co-injected with both AAV-BRI-Aβ40 and AAV-BRI-Aβ42. Brain tissue was analyzed by ELISA and immunohistochemistry to quantify levels of detergent soluble and insoluble Aβ peptides. BRI-Aβ42 and the combination of BRI-Aβ40+42 overexpression resulted in elevated levels of detergent-insoluble Aβ. No significant increase in detergent-insoluble Aβ was seen in the rats expressing APPsw or BRI-Aβ40. No pathological features were noted in any rats, except the AAV-BRI-Aβ42 rats which showed focal, amorphous, Thioflavin-negative Aβ42 deposits. Conclusion The results show that AAV-mediated gene transfer is a valuable tool to model aspects of AD pathology in

  3. FPGA Based Compensation Method for Correcting Distortion in Voltage Inverters

    National Research Council Canada - National Science Library

    Williamson, Kenya D

    2007-01-01

    ...) voltage source inverters. Blanking time distortion is caused by the delay inserted to prevent the short circuit that would occur if the two transistors in the same inverter leg are both on at the same time...

  4. Inverter Anti-Islanding with Advanced Grid Support in Single- and Multi-Inverter Islands

    Energy Technology Data Exchange (ETDEWEB)

    Hoke, Andy

    2016-08-16

    As PV and other DER systems are connected to the grid at increased penetration levels, island detection may become more challenging for two reasons: 1. In islands containing many DERs, active inverter-based anti-islanding methods may have more difficulty detecting islands because each individual inverter's efforts to detect the island may be interfered with by the other inverters in the island. 2. The increasing numbers of DERs are leading to new requirements that DERs ride through grid disturbances and even actively try to regulate grid voltage and frequency back towards nominal operating conditions. These new grid support requirements may directly or indirectly interfere with anti-islanding controls. This report describes a series of tests designed to examine the impacts of both grid support functions and multi-inverter islands on anti-islanding effectiveness.

  5. Dual AAV therapy ameliorates exercise-induced muscle injury and functional ischemia in murine models of Duchenne muscular dystrophy.

    Science.gov (United States)

    Zhang, Yadong; Yue, Yongping; Li, Liang; Hakim, Chady H; Zhang, Keqing; Thomas, Gail D; Duan, Dongsheng

    2013-09-15

    Neuronal nitric oxide synthase (nNOS) membrane delocalization contributes to the pathogenesis of Duchenne muscular dystrophy (DMD) by promoting functional muscle ischemia and exacerbating muscle injury during exercise. We have previously shown that supra-physiological expression of nNOS-binding mini-dystrophin restores normal blood flow regulation and prevents functional ischemia in transgenic mdx mice, a DMD model. A critical next issue is whether systemic dual adeno-associated virus (AAV) gene therapy can restore nNOS-binding mini-dystrophin expression and mitigate muscle activity-related functional ischemia and injury. Here, we performed systemic gene transfer in mdx and mdx4cv mice using a pair of dual AAV vectors that expressed a 6 kb nNOS-binding mini-dystrophin gene. Vectors were packaged in tyrosine mutant AAV-9 and co-injected (5 × 10(12) viral genome particles/vector/mouse) via the tail vein to 1-month-old dystrophin-null mice. Four months later, we observed 30-50% mini-dystrophin positive myofibers in limb muscles. Treatment ameliorated histopathology, increased muscle force and protected against eccentric contraction-induced injury. Importantly, dual AAV therapy successfully prevented chronic exercise-induced muscle force drop. Doppler hemodynamic assay further showed that therapy attenuated adrenergic vasoconstriction in contracting muscle. Our results suggest that partial transduction can still ameliorate nNOS delocalization-associated functional deficiency. Further evaluation of nNOS binding mini-dystrophin dual AAV vectors is warranted in dystrophic dogs and eventually in human patients.

  6. Tolerance induction to cytoplasmic beta-galactosidase by hepatic AAV gene transfer: implications for antigen presentation and immunotoxicity.

    Directory of Open Access Journals (Sweden)

    Ashley T Martino

    2009-08-01

    Full Text Available Hepatic gene transfer, in particular using adeno-associated viral (AAV vectors, has been shown to induce immune tolerance to several protein antigens. This approach has been exploited in animal models of inherited protein deficiency for systemic delivery of therapeutic proteins. Adequate levels of transgene expression in hepatocytes induce a suppressive T cell response, thereby promoting immune tolerance. This study addresses the question of whether AAV gene transfer can induce tolerance to a cytoplasmic protein.AAV-2 vector-mediated hepatic gene transfer for expression of cytoplasmic beta-galactosidase (beta-gal was performed in immune competent mice, followed by a secondary beta-gal gene transfer with E1/E3-deleted adenoviral Ad-LacZ vector to provoke a severe immunotoxic response. Transgene expression from the AAV-2 vector in approximately 2% of hepatocytes almost completely protected from inflammatory T cell responses against beta-gal, eliminated antibody formation, and significantly reduced adenovirus-induced hepatotoxicity. Consequently, approximately 10% of hepatocytes continued to express beta-gal 45 days after secondary Ad-LacZ gene transfer, a time point when control mice had lost all Ad-LacZ derived expression. Suppression of inflammatory T cell infiltration in the liver and liver damage was linked to specific transgene expression and was not seen for secondary gene transfer with Ad-GFP. A combination of adoptive transfer studies and flow cytometric analyses demonstrated induction of Treg that actively suppressed CD8(+ T cell responses to beta-gal and that was amplified in liver and spleen upon secondary Ad-LacZ gene transfer.These data demonstrate that tolerance induction by hepatic AAV gene transfer does not require systemic delivery of the transgene product and that expression of a cytoplasmic neo-antigen in few hepatocytes can induce Treg and provide long-term suppression of inflammatory responses and immunotoxicity.

  7. Low operating bias and matched input-output characteristics in graphene logic inverters.

    Science.gov (United States)

    Li, Song-Lin; Miyazaki, Hisao; Kumatani, Akichika; Kanda, Akinobu; Tsukagoshi, Kazuhito

    2010-07-14

    We developed a simple and novel method to fabricate complementary-like logic inverters based on ambipolar graphene field-effect transistors (FETs). We found that the top gate stacks (with both the metal and oxide layers) can be simply prepared with only one-step deposition process and show high capacitive efficiency. By employing such a top gate as the operating terminal, the operating bias can be lowered within 2 V. In addition, the complementary p- and n-type FET pairs can be also simply fulfilled through potential superposition effect from the drain bias. The inverters can be operated, with up to 4-7 voltage gains, in both the first and third quadrants due to the ambipolarity of graphene FETs. For the first time, a match between the input and output voltages is achieved in graphene logic devices, indicating the potential in direct cascading of multiple devices for future nanoelectronic applications.

  8. Efficient/reliable dc-to-dc inverter circuit

    Science.gov (United States)

    Pasciutti, E. R.

    1970-01-01

    Feedback loop, which contains an inductor in series with a saturable reactor, is added to a standard inverter circuit to permit the inverter power transistors to be switched in a controlled and efficient manner. This inverter is applicable where the power source has either high or low impedance properties.

  9. Do pregnant women know how to correct inverted nipples ...

    African Journals Online (AJOL)

    Inverted nipples occur in an estimated 9 to 10 percent of women globally, contributing to the number of women who are not exclusively breastfeeding their infants. Women with inverted nipples may want to breastfeed, but infants may be unable to latch to the breast. Inverted nipples can be corrected, but it is unclear if women ...

  10. Pulsewidth-modulated 2-source neutral-point-clamped inverter

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Loh, Poh Chang; Gao, Feng

    2007-01-01

    This paper presents the careful integration of a newly proposed Z-source topological concept to the basic neutral-point-clamped (NPC) inverter topology for designing a three-level inverter with both voltage-buck and voltage-boost capabilities. The designed Z-source NPC inverter uses two unique X-...

  11. Mobile Inverted Constructivism: Education of Interaction Technology in Social Media

    Science.gov (United States)

    Chai, Jia-Xiang; Fan, Kuo-Kuang

    2016-01-01

    The combination of social media and invert teaching is a new path to inverting interation technology education and reconstructing the curriculum of context. In this paper, based on the theory of constructivism learning, a model named Mobile Inverted Constructivism (MIC) is provided. Moreover, in view of the functional quality of social media in…

  12. Power Inverter Topologies for Photovoltaic Modules - A Review

    DEFF Research Database (Denmark)

    Kjær, Søren Bækhøj; Pedersen, John Kim; Blaabjerg, Frede

    2002-01-01

    This review-paper focuses on the latest development of inverters for photovoltaic AC-Modules. The power range for these inverters is usually within 90 Watt to 500 Watt, which covers the most commercial photovoltaic-modules. Self-commutated inverters have replaced the grid-commutated ones. The same...

  13. Diode-Assisted Buck-Boost Current Source Inverters

    DEFF Research Database (Denmark)

    Gao, F.; Cai, Liang; Loh, P.C.

    2007-01-01

    This paper presents a couple of novel current source inverters (CSIs) with the enhanced current buckboost capability. With the unique diode-inductor network added between current source inverter circuitry and current boost elements, the proposed buck-boost current source inverters demonstrate...

  14. A single phase photovoltaic inverter control for grid connected system

    Indian Academy of Sciences (India)

    during light load condition the excess energy generated from the PV inverter is fed to the grid and; during an overload condition or in case of unfavorable atmospheric conditions the load demand is met by both PV inverter and the grid. In order to synchronize the PV inverter with the grid a dual transport delay based phase ...

  15. Online Variable Topology-Type Photovoltaic Grid-Connected Inverter

    DEFF Research Database (Denmark)

    Wu, Fengjiang; Sun, Bo; Duan, Jiandong

    2015-01-01

    and H-bridge inverter under the conditions of variable output voltage and power of the PV array. It is proved that, compared with the H-bridge inverter, the operation range of the cascaded inverter is wider, whereas the total loss is larger. Furthermore, a novel online variable topology-type grid...

  16. DC-to-AC inverter ratio failure detector

    Science.gov (United States)

    Ebersole, T. J.; Andrews, R. E.

    1975-01-01

    Failure detection technique is based upon input-output ratios, which is independent of inverter loading. Since inverter has fixed relationship between V-in/V-out and I-in/I-out, failure detection criteria are based on this ratio, which is simply inverter transformer turns ratio, K, equal to primary turns divided by secondary turns.

  17. Complexity of immune responses to AAV transgene products - Example of factor IX.

    Science.gov (United States)

    Herzog, Roland W

    2017-05-29

    After two decades of research, in vivo gene transfer with adeno-associated viral (AAV) vectors has now resulted in successful treatments and even cures for several human diseases. However, the potential for immune responses against the therapeutic gene products remains one of the concerns as this approach is broadened to more patients, diverse diseases, and target organs. Immune responses following gene transfer of coagulation factor IX (FIX) for the treatment of the bleeding disorder hemophilia B has been extensively investigated in multiple animal models. Findings from these studies have not only influenced clinical trial design but have broader implications for other diseases. The impact of vector design and dose, as well as target organ/route of administration on humoral and cellular immune responses are reviewed. Furthermore, the potential for tolerance induction by hepatic gene transfer or combination with immune modulation is discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Transistor Clamped Five-Level Inverter using Non-Inverting Double Reference Single Carrier PWM Technique for photovoltaic applications

    DEFF Research Database (Denmark)

    Bhaskar, Mahajan Sagar; Padmanaban, Sanjeevikumar; Fedák, Viliam

    2017-01-01

    supplies or capacitor banks. To design the proposed five level inverter five numbers of power control switches and eight diodes are required. The proposed inverter circuitry is investigated by using Non-Inverting Double Reference Single Carrier PWM (NIDRSC PWM) Technique in terms of harmonics content...

  19. Synaptic pathology and therapeutic repair in adult retinoschisis mouse by AAV-RS1 transfer

    Science.gov (United States)

    Ou, Jingxing; Vijayasarathy, Camasamudram; Ziccardi, Lucia; Chen, Shan; Zeng, Yong; Marangoni, Dario; Pope, Jodie G.; Bush, Ronald A.; Wu, Zhijian; Li, Wei; Sieving, Paul A.

    2015-01-01

    Strategies aimed at invoking synaptic plasticity have therapeutic potential for several neurological conditions. The human retinal synaptic disease X-linked retinoschisis (XLRS) is characterized by impaired visual signal transmission through the retina and progressive visual acuity loss, and mice lacking retinoschisin (RS1) recapitulate human disease. Here, we demonstrate that restoration of RS1 via retina-specific delivery of adeno-associated virus type 8-RS1 (AAV8-RS1) vector rescues molecular pathology at the photoreceptor–depolarizing bipolar cell (photoreceptor-DBC) synapse and restores function in adult Rs1-KO animals. Initial development of the photoreceptor-DBC synapse was normal in the Rs1-KO retina; however, the metabotropic glutamate receptor 6/transient receptor potential melastatin subfamily M member 1–signaling (mGluR6/TRPM1-signaling) cascade was not properly maintained. Specifically, the TRPM1 channel and G proteins Gαo, Gβ5, and RGS11 were progressively lost from postsynaptic DBC dendritic tips, whereas the mGluR6 receptor and RGS7 maintained proper synaptic position. This postsynaptic disruption differed from other murine night-blindness models with an electronegative electroretinogram response, which is also characteristic of murine and human XLRS disease. Upon AAV8-RS1 gene transfer to the retina of adult XLRS mice, TRPM1 and the signaling molecules returned to their proper dendritic tip location, and the DBC resting membrane potential was restored. These findings provide insight into the molecular plasticity of a critical synapse in the visual system and demonstrate potential therapeutic avenues for some diseases involving synaptic pathology. PMID:26098217

  20. Synaptic pathology and therapeutic repair in adult retinoschisis mouse by AAV-RS1 transfer.

    Science.gov (United States)

    Ou, Jingxing; Vijayasarathy, Camasamudram; Ziccardi, Lucia; Chen, Shan; Zeng, Yong; Marangoni, Dario; Pope, Jodie G; Bush, Ronald A; Wu, Zhijian; Li, Wei; Sieving, Paul A

    2015-07-01

    Strategies aimed at invoking synaptic plasticity have therapeutic potential for several neurological conditions. The human retinal synaptic disease X-linked retinoschisis (XLRS) is characterized by impaired visual signal transmission through the retina and progressive visual acuity loss, and mice lacking retinoschisin (RS1) recapitulate human disease. Here, we demonstrate that restoration of RS1 via retina-specific delivery of adeno-associated virus type 8-RS1 (AAV8-RS1) vector rescues molecular pathology at the photoreceptor-depolarizing bipolar cell (photoreceptor-DBC) synapse and restores function in adult Rs1-KO animals. Initial development of the photoreceptor-DBC synapse was normal in the Rs1-KO retina; however, the metabotropic glutamate receptor 6/transient receptor potential melastatin subfamily M member 1-signaling (mGluR6/TRPM1-signaling) cascade was not properly maintained. Specifically, the TRPM1 channel and G proteins Gαo, Gβ5, and RGS11 were progressively lost from postsynaptic DBC dendritic tips, whereas the mGluR6 receptor and RGS7 maintained proper synaptic position. This postsynaptic disruption differed from other murine night-blindness models with an electronegative electroretinogram response, which is also characteristic of murine and human XLRS disease. Upon AAV8-RS1 gene transfer to the retina of adult XLRS mice, TRPM1 and the signaling molecules returned to their proper dendritic tip location, and the DBC resting membrane potential was restored. These findings provide insight into the molecular plasticity of a critical synapse in the visual system and demonstrate potential therapeutic avenues for some diseases involving synaptic pathology.

  1. rAAV-compatible MiniPromoters for restricted expression in the brain and eye.

    Science.gov (United States)

    de Leeuw, Charles N; Korecki, Andrea J; Berry, Garrett E; Hickmott, Jack W; Lam, Siu Ling; Lengyell, Tess C; Bonaguro, Russell J; Borretta, Lisa J; Chopra, Vikramjit; Chou, Alice Y; D'Souza, Cletus A; Kaspieva, Olga; Laprise, Stéphanie; McInerny, Simone C; Portales-Casamar, Elodie; Swanson-Newman, Magdalena I; Wong, Kaelan; Yang, George S; Zhou, Michelle; Jones, Steven J M; Holt, Robert A; Asokan, Aravind; Goldowitz, Daniel; Wasserman, Wyeth W; Simpson, Elizabeth M

    2016-05-10

    Small promoters that recapitulate endogenous gene expression patterns are important for basic, preclinical, and now clinical research. Recently, there has been a promising revival of gene therapy for diseases with unmet therapeutic needs. To date, most gene therapies have used viral-based ubiquitous promoters-however, promoters that restrict expression to target cells will minimize off-target side effects, broaden the palette of deliverable therapeutics, and thereby improve safety and efficacy. Here, we take steps towards filling the need for such promoters by developing a high-throughput pipeline that goes from genome-based bioinformatic design to rapid testing in vivo. For much of this work, therapeutically interesting Pleiades MiniPromoters (MiniPs; ~4 kb human DNA regulatory elements), previously tested in knock-in mice, were "cut down" to ~2.5 kb and tested in recombinant adeno-associated virus (rAAV), the virus of choice for gene therapy of the central nervous system. To evaluate our methods, we generated 29 experimental rAAV2/9 viruses carrying 19 different MiniPs, which were injected intravenously into neonatal mice to allow broad unbiased distribution, and characterized in neural tissues by X-gal immunohistochemistry for icre, or immunofluorescent detection of GFP. The data showed that 16 of the 19 (84 %) MiniPs recapitulated the expression pattern of their design source. This included expression of: Ple67 in brain raphe nuclei; Ple155 in Purkinje cells of the cerebellum, and retinal bipolar ON cells; Ple261 in endothelial cells of brain blood vessels; and Ple264 in retinal Müller glia. Overall, the methodology and MiniPs presented here represent important advances for basic and preclinical research, and may enable a paradigm shift in gene therapy.

  2. A PWM Controller of a Full Bridge Single-Phase Synchronous Inverter for Micro-Grid System

    Science.gov (United States)

    Rahman, Tawfikur; Motakabber, S. M. A.; Ibrahimy, M. I.; Raghib, Aliza ‘Aini Binti Md Ralib@ Md

    2017-12-01

    Nowadays, microgrid system technology is becoming popular for small area power management systems. It is essential to be less harmonic-distortion and high efficiency of the inverter for microgrid applications. Pulse width modulation (PWM) controller is a conventional switching control technique which is suitable to use in the microgrid connected power inverter system. The control method and algorithm of this technique are challenging, and different approaches are required to avoid the complexity for a customized solution of the microgrid application. This paper proposes a comparative analysis of different controller and their operational methods. A PWM controller is used to reduce the ripple voltage noise while a continuous current mode provides a small output ripple which gives steady-state error as zero on fundamental and cutoff frequency. To reduce the ripple current, higher frequency harmonic distortion, switching loss and phase noise, LC low pass filter is used on either side of input and output terminals. The proposed inverter is designed by MATLAB 2016a simulation software. A balanced load resistance (RL = 20.5 Ω) of star configuration and a dual input DC voltage of ± 35V are considered. In this design, the circuit parameters, the fundamental frequency of 50 Hz, the PWM duty cycle of 95%, the cutoff frequency of the switching controller of 33 kHz are considered. The inverter in this paper exhibits THD of 0.44% and overall efficiency approximately of 98%. The proposed inverter is expected to be suitable for microgrid applications.

  3. Advanced Control of Wheeled Inverted Pendulum Systems

    CERN Document Server

    Li, Zhijun; Fan, Liping

    2013-01-01

    Advanced Control of Wheeled Inverted Pendulum Systems is an orderly presentation of recent ideas for overcoming the complications inherent in the control of wheeled inverted pendulum (WIP) systems, in the presence of uncertain dynamics, nonholonomic kinematic constraints as well as underactuated configurations. The text leads the reader in a theoretical exploration of problems in kinematics,dynamics modeling, advanced control design techniques,and trajectory generation for WIPs. An important concern is how to deal with various uncertainties associated with the nominal model, WIPs being characterized by unstable balance and unmodelled dynamics and being subject to time-varying external disturbances for which accurate models are hard to come by.   The book is self-contained, supplying the reader with everything from mathematical preliminaries and the basic Lagrange-Euler-based derivation of dynamics equations to various advanced motion control and force control approaches as well as trajectory generation met...

  4. Micro-inverter solar panel mounting

    Science.gov (United States)

    Morris, John; Gilchrist, Phillip Charles

    2016-02-02

    Processes, systems, devices, and articles of manufacture are provided. Each may include adapting micro-inverters initially configured for frame-mounting to mounting on a frameless solar panel. This securement may include using an adaptive clamp or several adaptive clamps secured to a micro-inverter or its components, and using compressive forces applied directly to the solar panel to secure the adaptive clamp and the components to the solar panel. The clamps can also include compressive spacers and safeties for managing the compressive forces exerted on the solar panels. Friction zones may also be used for managing slipping between the clamp and the solar panel during or after installation. Adjustments to the clamps may be carried out through various means and by changing the physical size of the clamps themselves.

  5. Design of High Efficient MPPT Solar Inverter

    Directory of Open Access Journals (Sweden)

    Sunitha K. A.

    2017-01-01

    Full Text Available This work aims to design a High Efficient Maximum Power Point Tracking (MPPT Solar Inverter. A boost converter is designed in the system to boost the power from the photovoltaic panel. By this experimental setup a room consisting of 500 Watts load (eight fluorescent tubes is completely controlled. It is aimed to decrease the maintenance cost. A microcontroller is introduced for tracking the P&O (Perturb and Observe algorithm used for tracking the maximum power point. The duty cycle for the operation of the boost convertor is optimally adjusted by using MPPT controller. There is a MPPT charge controller to charge the battery as well as fed to inverter which runs the load. Both the P&O scheme with the fixed variation for the reference current and the intelligent MPPT algorithm were able to identify the global Maximum power point, however the performance of the MPPT algorithm was better.

  6. Design And Implementation Of Cost Effective Inverter

    Directory of Open Access Journals (Sweden)

    Niaz Morshedul Haque

    2017-10-01

    Full Text Available This paper deals with the design and construct of a 100 Watt 220 Volt and 50 Hz Inverter. The system is designed without any microcontroller and it has a cost-effective design architecture. The elementary purpose of this device is to transmute 12 V DC to 220 V AC. Snubber technology is used to diminish the reverse potential transients and excessive heat of transformer winding and transistor switches. Switching pulse generated by NE 555 timer circuit and comparator circuit was used to take signal strength input from its rear as well as from both sides for triggering the MOSFET switches. Another switch is used to invert pulse between two switching circuitries. A 5 volts regulator IC 7805 was used to supply fixed 5V for biasing the switching and amplifying circuitry.

  7. Electronic Document Management Using Inverted Files System

    Directory of Open Access Journals (Sweden)

    Suhartono Derwin

    2014-03-01

    Full Text Available The amount of documents increases so fast. Those documents exist not only in a paper based but also in an electronic based. It can be seen from the data sample taken by the SpringerLink publisher in 2010, which showed an increase in the number of digital document collections from 2003 to mid of 2010. Then, how to manage them well becomes an important need. This paper describes a new method in managing documents called as inverted files system. Related with the electronic based document, the inverted files system will closely used in term of its usage to document so that it can be searched over the Internet using the Search Engine. It can improve document search mechanism and document save mechanism.

  8. Electron Cloud with Inverted Beam Screens

    CERN Document Server

    Maury Cuna, H

    2011-01-01

    We report the results of computer simulations studying the effect of wrongly oriented LHC beam screens on the local electron-cloud heat load and density. At 3.5 or 7-TeV energy and for maximum secondary emission-yield values below 1.5, with the inverted sawtooth orientation about ten times higher heat load is expected than for the standard orientation, and the wrongly oriented sawtooth chambers could lead to a local heat-load bottleneck during the process of surface conditioning at 25-ns bunch spacing. The available cooling margin can be significantly increased by correcting the sawtooth orientations at least for two dipole magnets in LHC arc cells 26 and 32 R3, in order that there be no half-cell cooling loop containing more than one inverted screen.

  9. Electron Cloud with Inverted Beam Screens

    CERN Document Server

    Maury Cuna, H; CERN. Geneva. ATS Department

    2011-01-01

    We report the results of computer simulations studying the effect of wrongly oriented LHC beam screens on the local electron-cloud heat load and density. At 3.5 or 7-TeV energy and for maximum secondary emission-yield values below 1.5, with the inverted sawtooth orientation about ten times higher heat load is expected than for the standard orientation, and the wrongly oriented sawtooth chambers could lead to a local heatload bottleneck during the process of surface conditioning at 25-ns bunch spacing. The available cooling margin can be significantly increased by correcting the sawtooth orientations at least for two dipole magnets in LHC arc cells 26 and 32 R3, in order that there be no half-cell cooling loop containing more than one inverted screen.

  10. Stability Analysis Method of Parallel Inverter

    OpenAIRE

    Li, Jun; Chen, Jie; Xue, Yaru; Qiu, Ruichang; Liu, Zhigang

    2017-01-01

    In order to further provide theoretical support for the stability of an auxiliary inverter parallel system, a new model which covers most of control parameters needs to be established. However, the ability of the small-signal model established by the traditional method is extremely limited, so this paper proposes a new small-signal modeling method for the parallel system. The new small-signal model not only can analyze the influence of the droop parameters on the system performance, but also ...

  11. FET commutated current-FED inverter

    Science.gov (United States)

    Rippel, Wally E. (Inventor); Edwards, Dean B. (Inventor)

    1983-01-01

    A shunt switch comprised of a field-effect transistor (Q.sub.1) is employed to commutate a current-fed inverter (10) using thyristors (SCR1, SCR2) or bijunction transistors (Q.sub.2, Q.sub.3) in a full bridge (1, 2, 3, 4) or half bridge (5, 6) and transformer (T.sub.1) configuration. In the case of thyristors, a tapped inverter (12) is employed to couple the inverter to a dc source to back bias the thyristors during commutation. Alternatively, a commutation power supply (20) may be employed for that purpse. Diodes (D.sub.1, D.sub.2) in series with some voltage dropping element (resistor R.sub.12 or resistors R.sub.1, R.sub.2 or Zener diodes D.sub.4, D.sub.5) are connected in parallel with the thyristors in the half bridge and transformer configuration to assure sharing the back bias voltage. A clamp circuit comprised of a winding (18) negatively coupled to the inductor and a diode (D.sub.3) return stored energy from the inductor to the power supply for efficient operation with buck or boost mode.

  12. Stability Analysis Method of Parallel Inverter

    Directory of Open Access Journals (Sweden)

    Jun Li

    2017-01-01

    Full Text Available In order to further provide theoretical support for the stability of an auxiliary inverter parallel system, a new model which covers most of control parameters needs to be established. However, the ability of the small-signal model established by the traditional method is extremely limited, so this paper proposes a new small-signal modeling method for the parallel system. The new small-signal model not only can analyze the influence of the droop parameters on the system performance, but also can analyze the influence of the output impedance of the inverter, the unbalanced and nonlinear loads, and the power calculation method and cut-off frequency of the low-pass filter on the system performance and stability. Based on this method, this paper carries out a comprehensive analysis on the performance of a parallel inverter system. And the correctness of the modeling method and analysis process of the system performance and stability are verified by the consistency of the simulation and experimental results.

  13. In vivo expression of human ATP:cob(I)alamin adenosyltransferase (ATR) using recombinant adeno-associated virus (rAAV) serotypes 2 and 8.

    Science.gov (United States)

    Erger, Kirsten E; Conlon, Thomas J; Leal, Nicole A; Zori, Robert; Bobik, Thomas A; Flotte, Terence R

    2007-06-01

    Methylmalonic aciduria (MMA) is an autosomal recessive disease with symptoms that include ketoacidosis, lethargy, recurrent vomiting, dehydration, respiratory distress, muscular hypotonia and death due to methylmalonic acid levels that are up to 1000-fold greater than normal. CblB MMA, a subset of the mutations leading to MMA, is caused by a deficiency in the enzyme cob(I)alamin adenosyltransferase (ATR). No animal model currently exists for this disease. ATR functions within the mitochondria matrix in the final conversion of cobalamin into coenzyme B(12), adenosylcobalamin (AdoCbl). AdoCbl is a required coenzyme for the mitochondrial enzyme methylmalonyl-CoA mutase (MCM). The human ATR cDNA was cloned into a recombinant adeno-associated virus (rAAV) vector and packaged into AAV 2 or 8 capsids and delivered by portal vein injection to C57/Bl6 mice at a dose of 1 x 10(10) and 1 x 10(11) particles. Eight weeks post-injection RNA, genomic DNA and protein were then extracted and analyzed. Using primer pairs specific to the cytomegalovirus (CMV) enhancer/chicken beta-actin (CBAT) promoter within the rAAV vectors, genome copy numbers were found to be 0.03, 2.03 and 0.10 per cell in liver for the rAAV8 low dose, rAAV8 high dose and rAAV2 high dose, respectively. Western blotting performed on mitochondrial protein extracts demonstrated protein levels were comparable to control levels in the rAAV8 low dose and rAAV2 high dose animals and 3- to 5-fold higher than control levels were observed in high dose animals. Immunostaining demonstrated enhanced transduction efficiency of hepatocytes to over 40% in the rAAV8 high dose animals, compared to 9% and 5% transduction in rAAV2 high dose and rAAV8 low dose animals, respectively. These data demonstrate the feasibility of efficient ATR gene transfer to the liver as a prelude to future gene therapy experiments.

  14. Angiotensin 1-7 Overexpression Mediated by a Capsid-optimized AAV8 Vector Leads to Significant Growth Inhibition of Hepatocellular Carcinoma In vivo.

    Science.gov (United States)

    Mao, Yingying; Pei, Nana; Chen, Xinglu; Chen, Huiying; Yan, Renhe; Bai, Na; Li, Andrew; Li, Jinlong; Zhang, Yanling; Du, Hongyan; Chen, Baihong; Sumners, Colin; Wang, Xuejun; Wang, Shengqi; Li, Hongwei

    2018-01-01

    Background: Angiotensin-(1-7) [Ang-(1-7)] has been identified to inhibit the growth of many types of tumor cells both in vitro and in vivo . However, the rapid degradation of Ang-(1-7) in vivo limits its clinical application. Adeno-associated virus (AAV) serotype-8 is a remarkable vector for long-term in vivo gene delivery. Method: This study was designed to investigate the effects of AAV-mediated Ang-(1-7) overexpression on hepatocellular carcinoma. We first generated three different tyrosine (Y) to phenylalanine (F) mutants of AAV8 (Y447F, Y703F, Y708F) and evaluated their in vivo transduction efficiencies. Results: The data indicated that the Y703F mutant elicited a significant enhancement of liver gene delivery when compared with wild-type AAV8 (wtAAV8). The anti-tumor effect of Ang-(1-7) mediated by this optimized vector was evaluated in H22 hepatoma-bearing mice. Our results demonstrated that AAV-Ang-(1-7) persistently inhibited the growth of hepatocellular carcinoma by significantly downregulating angiogenesis. This was confirmed by observed decreases in the levels of the proangiogenic factors VEGF and PIGF. Conclusion: Collectively, these data suggest that Ang-(1-7) overexpression mediated by the optimized vector may be an effective alternative for hepatocellular carcinoma therapy due to its long-term and significant anti-tumor activity.

  15. In vivo genome editing in animals using AAV-CRISPR system: applications to translational research of human disease [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Cia-Hin Lau

    2017-12-01

    Full Text Available Adeno-associated virus (AAV has shown promising therapeutic efficacy with a good safety profile in a wide range of animal models and human clinical trials. With the advent of clustered regulatory interspaced short palindromic repeat (CRISPR-based genome-editing technologies, AAV provides one of the most suitable viral vectors to package, deliver, and express CRISPR components for targeted gene editing. Recent discoveries of smaller Cas9 orthologues have enabled the packaging of Cas9 nuclease and its chimeric guide RNA into a single AAV delivery vehicle for robust in vivo genome editing. Here, we discuss how the combined use of small Cas9 orthologues, tissue-specific minimal promoters, AAV serotypes, and different routes of administration has advanced the development of efficient and precise in vivo genome editing and comprehensively review the various AAV-CRISPR systems that have been effectively used in animals. We then discuss the clinical implications and potential strategies to overcome off-target effects, immunogenicity, and toxicity associated with CRISPR components and AAV delivery vehicles. Finally, we discuss ongoing non-viral-based ex vivo gene therapy clinical trials to underscore the current challenges and future prospects of CRISPR/Cas9 delivery for human therapeutics.

  16. Biochemical and physiological improvement in a mouse model of Smith–Lemli–Opitz syndrome (SLOS following gene transfer with AAV vectors

    Directory of Open Access Journals (Sweden)

    Lee Ying

    2014-01-01

    Full Text Available Smith–Lemli–Opitz syndrome (SLOS is an inborn error of cholesterol synthesis resulting from a defect in 7-dehydrocholesterol reductase (DHCR7, the enzyme that produces cholesterol from its immediate precursor 7-dehydrocholesterol. Current therapy employing dietary cholesterol is inadequate. As SLOS is caused by a defect in a single gene, restoring enzyme functionality through gene therapy may be a direct approach for treating this debilitating disorder. In the present study, we first packaged a human DHCR7 construct into adeno-associated virus (AAV vectors having either type-2 (AAV2 or type-8 (AAV2/8 capsid, and administered treatment to juvenile mice. While a positive response (assessed by increases in serum and liver cholesterol was seen in both groups, the improvement was greater in the AAV2/8–DHCR7 treated mice. Newborn mice were then treated with AAV2/8–DHCR7 and these mice, compared to mice treated as juveniles, showed higher DHCR7 mRNA expression in liver and a greater improvement in serum and liver cholesterol levels. Systemic treatment did not affect brain cholesterol in any of the experimental groups. Both juvenile and newborn treatments with AAV2/8–DHCR7 resulted in increased rates of weight gain indicating that gene transfer had a positive physiological effect.

  17. Comparing the aerodynamic forces produced by dragonfly forewings during inverted and non-inverted flight

    Science.gov (United States)

    Shumway, Nathan; Gabryszuk, Mateusz; Laurence, Stuart

    2017-11-01

    Experiments were conducted with live dragonflies to determine their wing kinematics during free flight. The motion of one forewing in two different tests, one where the dragonfly is inverted, is described using piecewise functions and simulated using the OVERTURNS Reynolds-averaged Navier-Stokes solver that has been used in previous work to determine trim conditions for a fruit fly model. For the inverted dragonfly the upstrokes were significantly longer than the downstrokes, pitching amplitude is lower than that for the right-side up flight and the flap amplitude is larger. Simulations of dragonfly kinematics of a single forewing are presented to determine how the forces differ for a dragonfly flying inverted and a dragonfly flying right-side up. This work was supported by the United States Army Research Laboratory's Micro Autonomous Systems and Technology Collaborative Technology Alliance Project MCE-16-17 1.2.

  18. B-cell depletion is protective against anti-AAV capsid immune response: a human subject case study

    Directory of Open Access Journals (Sweden)

    M Corti

    2014-01-01

    Full Text Available Gene therapy strategies for congenital myopathies may require repeat administration of adeno-associated viral (AAV vectors due to aspects of the clinical application, such as: (i administration of doses below therapeutic efficacy in patients enrolled in early phase clinical trials; (ii progressive reduction of the therapeutic gene expression over time as a result of increasing muscle mass in patients treated at a young age; and (iii a possibly faster depletion of pathogenic myofibers in this patient population. Immune response triggered by the first vector administration, and to subsequent doses, represents a major obstacle for successful gene transfer in young patients. Anti-capsid and anti-transgene product related humoral and cell-mediated responses have been previously observed in all preclinical models and human subjects who received gene therapy or enzyme replacement therapy (ERT for congenital myopathies. Immune responses may result in reduced efficacy of the gene transfer over time and/or may preclude for the possibility of re-administration of the same vector. In this study, we evaluated the immune response of a Pompe patient dosed with an AAV1-GAA vector after receiving Rituximab and Sirolimus to modulate reactions against ERT. A key finding of this single subject case report is the observation that B-cell ablation with rituximab prior to AAV vector exposure results in non-responsiveness to both capsid and transgene, therefore allowing the possibility of repeat administration in the future. This observation is significant for future gene therapy studies and establishes a clinically relevant approach to blocking immune responses to AAV vectors.

  19. Depressive-like phenotype induced by AAV-mediated overexpression of human α-synuclein in midbrain dopaminergic neurons.

    Science.gov (United States)

    Caudal, D; Alvarsson, A; Björklund, A; Svenningsson, P

    2015-11-01

    Parkinson's disease (PD) is a neurodegenerative disorder characterized by a progressive loss of nigral dopaminergic neurons and by the presence of aggregates containing α-synuclein called Lewy bodies. Viral vector-induced overexpression of α-synuclein in dopaminergic neurons represents a model of PD which recapitulates disease progression better than commonly used neurotoxin models. Previous studies using this model have reported motor and cognitive impairments, whereas depression, mood and anxiety phenotypes are less described. To investigate these psychiatric phenotypes, Sprague-Dawley rats received bilateral injections of a recombinant adeno-associated virus (AAV) vector expressing human α-synuclein or GFP into the substantia nigra pars compacta. Behavior was assessed at two timepoints: 3 and 8 weeks post-injection. We report that nigral α-synuclein overexpression led to a pronounced nigral dopaminergic cell loss accompanied by a smaller cell loss in the ventral tegmental area, and to a decreased striatal density of dopaminergic fibers. The AAV-α-synuclein group exhibited modest, but significant motor impairments 8 weeks after vector administration. The AAV-α-synuclein group displayed depressive-like behavior in the forced swim test after 3 weeks, and reduced sucrose preference at week 8. At both timepoints, overexpression of α-synuclein was linked to a hyperactive hypothalamic-pituitary-adrenal (HPA) axis regulation of corticosterone. The depressive-like phenotype was also correlated with decreased nigral brain-derived neurotrophic factor and spinophilin levels, and with decreased striatal levels of the activity-regulated cytoskeleton-associated protein. This study demonstrates that AAV-mediated α-synuclein overexpression in dopamine neurons is not only useful to model motor impairments of PD, but also depression. This study also provides evidence that depression in experimental Parkinsonism is correlated to dysregulation of the HPA axis and to

  20. AAV-mediated targeting of gene expression to the peri-infarct region in rat cortical stroke model.

    Science.gov (United States)

    Mätlik, Kert; Abo-Ramadan, Usama; Harvey, Brandon K; Arumäe, Urmas; Airavaara, Mikko

    2014-10-30

    For stroke patients the recovery of cognitive and behavioral functions is often incomplete. Functional recovery is thought to be mediated largely by connectivity rearrangements in the peri-infarct region. A method for manipulating gene expression in this region would be useful for identifying new recovery-enhancing treatments. We have characterized a way of targeting adeno-associated virus (AAV) vectors to the peri-infarct region of cortical ischemic lesion in rats 2days after middle cerebral artery occlusion (MCAo). We used magnetic resonance imaging (MRI) to show that the altered properties of post-ischemic brain tissue facilitate the spreading of intrastriatally injected nanoparticles toward the infarct. We show that subcortical injection of green fluorescent protein-encoding dsAAV7-GFP resulted in transduction of cells in and around the white matter tract underlying the lesion, and in the cortex proximal to the lesion. A similar result was achieved with dsAAV7 vector encoding the cerebral dopamine neurotrophic factor (CDNF), a protein with therapeutic potential. Viral vector-mediated intracerebral gene delivery has been used before in rodent models of ischemic injury. However, the method of targeting gene expression to the peri-infarct region, after the initial phase of ischemic cell death, has not been described before. We demonstrate a straightforward and robust way to target AAV vector-mediated over-expression of genes to the peri-infarct region in a rat stroke model. This method will be useful for studying the action of specific proteins in peri-infarct region during the recovery process. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Pre-clinical evaluation of AAV5-miHTT gene therapy of Huntington´s disease

    Czech Academy of Sciences Publication Activity Database

    Konstantinová, P.; Miniarikova, J.; Blits, B.; Zimmer, V.; Spoerl, A.; Southwell, A.; Hayden, M.; van Deventer, S.; Deglon, N.; Motlík, Jan; Juhás, Štefan; Juhásová, Jana; Richard, Ch.; Petry, H.

    2015-01-01

    Roč. 78, Supl 2 (2015), s. 8-8 ISSN 1210-7859. [Conference on Animal Models for neurodegenerative Diseases /3./. 08.11.2015-10.11.2015, Liblice] R&D Projects: GA MŠk ED2.1.00/03.0124 Institutional support: RVO:67985904 Keywords : Huntington´s disease * gene therapy * AAV5-miHTT Subject RIV: EB - Gene tics ; Molecular Biology

  2. AAV-based shRNA silencing of NF-κB ameliorates muscle pathologies in mdx mice.

    Science.gov (United States)

    Yang, Q; Tang, Y; Imbrogno, K; Lu, A; Proto, J D; Chen, A; Guo, F; Fu, F H; Huard, J; Wang, B

    2012-12-01

    Chronic inflammation, promoted by an upregulated NF-kappa B (NF-κB) pathway, has a key role in Duchenne muscular dystrophy (DMD) patients' pathogenesis. Blocking the NF-κB pathway has been shown to be a viable approach to diminish chronic inflammation and necrosis in the dystrophin-defective mdx mouse, a murine DMD model. In this study, we used the recombinant adeno-associated virus serotype 9 (AAV9) carrying an short hairpin RNA (shRNA) specifically targeting the messenger RNA of NF-κB/p65 (p65-shRNA), the major subunit of NF-κB associated with chronic inflammation in mdx mice. We examined whether i.m. AAV9-mediated delivery of p65-shRNA could decrease NF-κB activation, allowing for amelioration of muscle pathologies in 1- and 4-month-old mdx mice. At 1 month after treatment, NF-κB/p65 levels were significantly decreased by AAV gene transfer of p65-shRNA in the two ages of treatment groups, with necrosis significantly decreased compared with controls. Quantitative analysis revealed that central nucleation (CN) of the myofibers of p65-shRNA-treated 1-month-old mdx muscles was reduced from 67 to 34%, but the level of CN was not significantly decreased in treated 4-month-old mdx mice. Moreover, delivery of the p65-shRNA enhanced the capacity of myofiber regeneration in old mdx mice treated at 4 months of age when the dystrophic myofibers were most exhausted; however, such p65 silencing diminished the myofiber regeneration in young mdx mice treated at 1 month of age. Taken together, these findings demonstrate that the AAV-mediated delivery of p65-shRNA has the capacity to ameliorate muscle pathologies in mdx mice by selectively reducing NF-κB/p65 activity.

  3. A Translational Pathway Toward a Clinical Trial Using the Second-Generation AAV Micro-Dystrophin Vector

    Science.gov (United States)

    2016-09-01

    commonly used animal models for DMD.[18–22] Over the years, a number of different strategies have been developed to achieve effective AAV gene transfer in...and sarcoglycan gene therapies have signifi- cantly improved the cardiac outcome in animal models of DMD and LGMD, respectively. ● Targeting ...mediated local exon-skipping. [91,92] Compared to RNA editing with exon-skipping, targeted editing of themutated dystrophin gene has just entered an

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    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  18. kjfk Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  19. kbna Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  20. kbvi Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  1. kiah Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  2. kbzn Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  3. kfnt Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  4. kbpt Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  5. koun Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  7. kspi Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  8. kclm Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  9. kipl Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  10. kpbi Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  18. kbpk Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  1. kgfl Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  2. pgwt Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  6. kipt Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  7. kpeq Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  8. kdug Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  9. klbt Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  10. kcys Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  11. khio Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  12. kflo Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  13. klaf Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  14. kmlu Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  15. kact Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  16. khob Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  17. ktcs Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  18. kdnl Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  19. kmgw Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  20. kryy Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  1. kgtf Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  2. kjax Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  3. ktvf Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  4. kfat Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  5. kink Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  6. kshv Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  7. pajn Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  8. kpna Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  9. ktph Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  10. ksux Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  11. kcon Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  12. kpnc Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  13. kgsp Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  14. kgpt Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  15. kgcn Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  16. kart Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  17. pagk Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  1. krsw Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

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    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  9. kagc Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  10. kbmi Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  11. kapn Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  12. kgon Terminal Aerodrome Forecast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TAF (terminal aerodrome forecast or terminal area forecast) is a format for reporting weather forecast information, particularly as it relates to aviation. TAFs are...

  13. Intracranial injection of AAV expressing NEP but not IDE reduces amyloid pathology in APP+PS1 transgenic mice.

    Directory of Open Access Journals (Sweden)

    Nikisha Carty

    Full Text Available The accumulation of β-amyloid peptides in the brain has been recognized as an essential factor in Alzheimer's disease pathology. Several proteases, including Neprilysin (NEP, endothelin converting enzyme (ECE, and insulin degrading enzyme (IDE, have been shown to cleave β-amyloid peptides (Aβ. We have previously reported reductions in amyloid in APP+PS1 mice with increased expression of ECE. In this study we compared the vector-induced increased expression of NEP and IDE. We used recombinant adeno-associated viral vectors expressing either native forms of NEP (NEP-n or IDE (IDE-n, or engineered secreted forms of NEP (NEP-s or IDE (IDE-s. In a six-week study, immunohistochemistry staining for total Aβ was significantly decreased in animals receiving the NEP-n and NEP-s but not for IDE-n or IDE-s in either the hippocampus or cortex. Congo red staining followed a similar trend revealing significant decreases in the hippocampus and the cortex for NEP-n and NEP-s treatment groups. Our results indicate that while rAAV-IDE does not have the same therapeutic potential as rAAV-NEP, rAAV-NEP-s and NEP-n are effective at reducing amyloid loads, and both of these vectors continue to have significant effects nine months post-injection. As such, they may be considered reasonable candidates for gene therapy trials in AD.

  14. Healthy and diseased corticospinal motor neurons are selectively transduced upon direct AAV2-2 injection into the motor cortex.

    Science.gov (United States)

    Jara, J H; Stanford, M J; Zhu, Y; Tu, M; Hauswirth, W W; Bohn, M C; DeVries, S H; Özdinler, P H

    2016-03-01

    Direct gene delivery to the neurons of interest, without affecting other neuron populations in the cerebral cortex, represent a challenge owing to the heterogeneity and cellular complexity of the brain. Genetic modulation of corticospinal motor neurons (CSMN) is required for developing effective and long-term treatment strategies for motor neuron diseases, in which voluntary movement is impaired. Adeno-associated viruses (AAV) have been widely used for neuronal transduction studies owing to long-term and stable gene expression as well as low immunoreactivity in humans. Here we report that AAV2-2 transduces CSMN with high efficiency upon direct cortex injection and that transduction efficiencies are similar during presymptomatic and symptomatic stages in hSOD1(G93A) transgenic amyotrophic lateral sclerosis (ALS) mice. Our findings reveal that choice of promoter improves selectivity as AAV2-2 chicken β-actin promoter injection results in about 70% CSMN transduction, the highest percentage reported to date. CSMN transduction in both wild-type and transgenic ALS mice allows detailed analysis of single axon fibers within the corticospinal tract in both cervical and lumbar spinal cord and reveals circuitry defects, which mainly occur between CSMN and spinal motor neurons in hSOD1(G93A) transgenic ALS mice. Our findings set the stage for CSMN gene therapy in ALS and related motor neuron diseases.

  15. Widespread gene transfer in the central nervous system of cynomolgus macaques following delivery of AAV9 into the cisterna magna

    Directory of Open Access Journals (Sweden)

    Christian Hinderer

    2014-01-01

    Full Text Available Adeno-associated virus serotype 9 (AAV9 vectors have recently been shown to transduce cells throughout the central nervous system of nonhuman primates when injected into the cerebrospinal fluid (CSF, a finding which could lead to a minimally invasive approach to treat genetic and acquired diseases affecting the entire CNS. We characterized the transduction efficiency of two routes of vector administration into the CSF of cynomolgus macaques—lumbar puncture, which is typically used in clinical practice, and suboccipital puncture, which is more commonly used in veterinary medicine. We found that delivery of vector into the cisterna magna via suboccipital puncture is up to 100-fold more efficient for achieving gene transfer to the brain. In addition, we evaluated the inflammatory response to AAV9-mediated GFP expression in the nonhuman primate CNS. We found that while CSF lymphocyte counts increased following gene transfer, there were no clinical or histological signs of immune toxicity. Together these data indicate that delivery of AAV9 into the cisterna magna is an effective method for achieving gene transfer in the CNS, and suggest that adapting this uncommon injection method for human trials could vastly increase the efficiency of gene delivery.

  16. AAV-mediated Sirt1 overexpression in skeletal muscle activates oxidative capacity but does not prevent insulin resistance

    Directory of Open Access Journals (Sweden)

    Laia Vil

    2016-01-01

    Full Text Available Type 2 diabetes is characterized by triglyceride accumulation and reduced lipid oxidation capacity in skeletal muscle. SIRT1 is a key protein in the regulation of lipid oxidation and its expression is reduced in the skeletal muscle of insulin resistant mice. In this tissue, Sirt1 up-regulates the expression of genes involved in oxidative metabolism and improves mitochondrial function mainly through PPARGC1 deacetylation. Here we examined whether Sirt1 overexpression mediated by adeno-associated viral vectors of serotype 1 (AAV1 specifically in skeletal muscle can counteract the development of insulin resistance induced by a high fat diet in mice. AAV1-Sirt1-treated mice showed up-regulated expression of key genes related to β-oxidation together with increased levels of phosphorylated AMP protein kinase. Moreover, SIRT1 overexpression in skeletal muscle also increased basal phosphorylated levels of AKT. However, AAV1-Sirt1 treatment was not enough to prevent high fat diet-induced obesity and insulin resistance. Although Sirt1 gene transfer to skeletal muscle induced changes at the muscular level related with lipid and glucose homeostasis, our data indicate that overexpression of SIRT1 in skeletal muscle is not enough to improve whole-body insulin resistance and that suggests that SIRT1 has to be increased in other metabolic tissues to prevent insulin resistance.

  17. Sexually dimorphic patterns of episomal rAAV genome persistence in the adult mouse liver and correlation with hepatocellular proliferation.

    Science.gov (United States)

    Dane, Allison P; Cunningham, Sharon C; Graf, Nicole S; Alexander, Ian E

    2009-09-01

    Recombinant adeno-associated virus vectors (rAAVs) show exceptional promise for liver-targeted gene therapy, with phenotype correction in small and large animal disease models being reported with increasing frequency. Success in humans, however, remains a considerable challenge that demands greater understanding of host-vector interactions, notably those governing the efficiency of initial gene transfer and subsequent long-term persistence of gene expression. In this study, we examined long-term enhanced green fluorescent protein (eGFP) expression and vector genome persistence in the mouse liver after rAAV2/8-mediated gene transfer in early adulthood. Two intriguing findings emerged of considerable scientific and clinical interest. First, adult female and male mice showed distinctly different patterns of persistence of eGFP expression across the hepatic lobule after exhibiting similar patterns initially. Female mice retained a predominantly perivenous pattern of expression, whereas male mice underwent inversion of this pattern with preferential loss of perivenous expression and relative retention of periportal expression. Second, these changing patterns of expression correlated with sexually dimorphic patterns of genome persistence that appear linked both spatially and temporally to underlying hepatocellular proliferation. Observation of the equivalent phenomenon in man could have significant implications for the long-term therapeutic efficacy of rAAV-mediated gene transfer, particularly in the context of correction of liver functions showing metabolic zonation.

  18. Impact of intravenous infusion time on AAV8 vector pharmacokinetics, safety, and liver transduction in cynomolgus macaques

    Directory of Open Access Journals (Sweden)

    Jenny A Greig

    2016-01-01

    Full Text Available Systemically delivered adeno-associated viral (AAV vectors are now in early-phase clinical trials for a variety of diseases. While there is a general consensus on inclusion and exclusion criteria for each of these trials, the conditions under which vectors are infused vary significantly. In this study, we evaluated the impact of intravenous infusion rate of AAV8 vector in cynomolgus macaques on transgene expression, vector clearance from the circulation, and potential activation of the innate immune system. The dose of AAV8 vector in terms of genome copies per kilogram body weight and its concentration were fixed, while the rate of infusion varied to deliver the entire dose over different time periods, including 1, 10, or 90 minutes. Analyses during the in-life phase of the experiment included sequential evaluation of whole blood for vector genomes and appearance of proinflammatory cytokines. Liver tissues were analyzed at the time of necropsy for enhanced green fluorescent protein (eGFP expression and vector genomes. The data were remarkable with a relative absence of any statistically significant effect of infusion time on vector transduction, safety, and clearance. However, some interesting and unexpected trends did emerge.

  19. Peripheral blood aspirates overexpressing IGF-I via rAAV gene transfer undergo enhanced chondrogenic differentiation processes.

    Science.gov (United States)

    Frisch, Janina; Orth, Patrick; Rey-Rico, Ana; Venkatesan, Jagadeesh Kumar; Schmitt, Gertrud; Madry, Henning; Kohn, Dieter; Cucchiarini, Magali

    2017-11-01

    Implantation of peripheral blood aspirates induced towards chondrogenic differentiation upon genetic modification in sites of articular cartilage injury may represent a powerful strategy to enhance cartilage repair. Such a single-step approach may be less invasive than procedures based on the use of isolated or concentrated MSCs, simplifying translational protocols in patients. In this study, we provide evidence showing the feasibility of overexpressing the mitogenic and pro-anabolic insulin-like growth factor I (IGF-I) in human peripheral blood aspirates via rAAV-mediated gene transfer, leading to enhanced proliferative and chondrogenic differentiation (proteoglycans, type-II collagen, SOX9) activities in the samples relative to control (reporter rAAV-lacZ) treatment over extended periods of time (at least 21 days, the longest time-point evaluated). Interestingly, IGF-I gene transfer also triggered hypertrophic, osteo- and adipogenic differentiation processes in the aspirates, suggesting that careful regulation of IGF-I expression may be necessary to contain these events in vivo. Still, the current results demonstrate the potential of targeting human peripheral blood aspirates via therapeutic rAAV transduction as a novel, convenient tool to treat articular cartilage injuries. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  20. Ab-externo AAV-mediated gene delivery to the suprachoroidal space using a 250 micron flexible microcatheter.

    Directory of Open Access Journals (Sweden)

    Marc C Peden

    2011-02-01

    Full Text Available The current method of delivering gene replacement to the posterior segment of the eye involves a three-port pars plana vitrectomy followed by injection of the agent through a 37-gauge cannula, which is potentially wrought with retinal complications. In this paper we investigate the safety and efficacy of delivering adeno-associated viral (AAV vector to the suprachoroidal space using an ab externo approach that utilizes an illuminated microcatheter.6 New Zealand White rabbits and 2 Dutch Belted rabbits were used to evaluate the ab externo delivery method. sc-AAV5-smCBA-hGFP vector was delivered into the suprachoroidal space using an illuminated iTrackTM 250A microcatheter. Six weeks after surgery, the rabbits were sacrificed and their eyes evaluated for AAV transfection using immunofluorescent antibody staining of GFP.Immunostaining of sectioned and whole-mounted eyes demonstrated robust transfection in all treated eyes, with no fluorescence in untreated control eyes. Transfection occurred diffusely and involved both the choroid and the retina. No apparent adverse effects caused by either the viral vector or the procedure itself could be seen either clinically or histologically.The ab externo method of delivery using a microcatheter was successful in safely and effectively delivering a gene therapy agent to the suprachoroidal space. This method presents a less invasive alternative to the current method of virally vectored gene delivery.

  1. Targeting Visceral Fat by Intraperitoneal Delivery of Novel AAV Serotype Vector Restricting Off-Target Transduction in Liver

    Directory of Open Access Journals (Sweden)

    Wei Huang

    2017-09-01

    Full Text Available It is challenging to genetically manipulate fat in adults. We demonstrate that intraperitoneal (i.p. injection of an engineered adeno-associated virus (AAV serotype Rec2 leads to high transduction of multiple visceral fat depots at a dose of 1 to 2 orders lower than commonly used doses for systemic gene delivery. To target adipose tissue, we develop a single AAV vector harboring two expression cassettes: one using the CBA promoter to drive transgene expression and one using the liver-specific albumin promoter to drive a microRNA-targeting WPRE sequence that only exists in this AAV vector. This dual-cassette vector achieves highly selective transduction of visceral fat while severely restricting off-target transduction of liver. As proof of efficacy, i.p. administration of an adipose-targeting Rec2 vector harboring the leptin gene corrects leptin deficiency, obesity, and metabolic syndromes of ob/ob mice. This study provides a powerful tool to genetically manipulate fat for basic research and gene therapies of genetic and acquired diseases.

  2. E Pluribus Unum: 50 Years of Research, Millions of Viruses, and One Goal--Tailored Acceleration of AAV Evolution.

    Science.gov (United States)

    Grimm, Dirk; Zolotukhin, Sergei

    2015-12-01

    Fifty years ago, a Science paper by Atchison et al. reported a newly discovered virus that would soon become known as adeno-associated virus (AAV) and that would subsequently emerge as one of the most versatile and most auspicious vectors for human gene therapy. A large part of its attraction stems from the ease with which the viral capsid can be engineered for particle retargeting to cell types of choice, evasion from neutralizing antibodies or other desirable properties. Particularly powerful and in the focus of the current review are high-throughput methods aimed at expanding the repertoire of AAV vectors by means of directed molecular evolution, such as random mutagenesis, DNA family shuffling, in silico reconstruction of ancestral capsids, or peptide display. Here, unlike the wealth of prior reviews on this topic, we especially emphasize and critically discuss the practical aspects of the different procedures that affect the ultimate outcome, including diversification protocols, combinatorial library complexity, and selection strategies. Our overall aim is to provide general guidance that should help users at any level, from novice to expert, to safely navigate through the rugged space of directed AAV evolution while avoiding the pitfalls that are associated with these challenging but promising technologies.

  3. Evaluasi Kinerja Angkutan Umum Trayek Terminal Oebobo - Terminal Kupang Pp Dan Terminal Kupang - Terminal Noelbaki Pp

    OpenAIRE

    Safe, Yohanes T; Udiana, I Made; Bella, Rosmiyati A

    2015-01-01

    Beberapa ruas jalan pada Trayek Terminal Oebobo-Terminal Kupang PP dan trayek Terminal Kupang-Terminal Noelbaki PP, pada jam-jam puncak angkutan umum yang ada cenderung digunakan melebihi kapasitas maksimumnya. Keadaan sebaliknya terjadi pada jam non-puncak, kendaraan umum setengah kosong dan harus melakukan kompetisi dengan angkutan umum lainnya untuk mendapatkan penumpang. Tujuan dari penelitian adalah mengetahui kinerja pelayanan angkutan umum, kebutuhan angkutan umum dan membuat rekomenda...

  4. Carbidopa-based modulation of the functional effect of the AAV2-hAADC gene therapy in 6-OHDA lesioned rats.

    Directory of Open Access Journals (Sweden)

    Agnieszka Ciesielska

    Full Text Available Progressively blunted response to L-DOPA in Parkinson's disease (PD is a critical factor that complicates long-term pharmacotherapy in view of the central importance of this drug in management of the PD-related motor disturbance. This phenomenon is likely due to progressive loss of one of the key enzymes involved in the biosynthetic pathway for dopamine in the basal ganglia: aromatic L-amino acid decarboxylase (AADC. We have developed a gene therapy based on an adeno-associated virus encoding human AADC (AAV2-hAADC infused into the Parkinsonian striatum. Although no adverse clinical effects of the AAV2-hAADC gene therapy have been observed so far, the ability to more precisely regulate transgene expression or transgene product activity could be an important long-term safety feature. The present study was designed to define pharmacological regulation of the functional activity of AAV2-hAADC transgene product by manipulating L-DOPA and carbidopa (AADC inhibitor administration in hemi-parkinsonian rats. Thirty days after unilateral striatal infusion of AAV2-hAADC, animals displayed circling behavior and acceleration of dopamine metabolism in the lesioned striatum after administration of a low dose of L-DOPA (5 mg/kg co-administered with 1.25 mg/kg of carbidopa. This phenomenon was not observed in control AAV2-GFP-treated rats. Withdrawal of carbidopa from a daily L-DOPA regimen decreased the peripheral L-DOPA pool, resulting in almost total loss of L-DOPA-induced behavioral response in AAV2-hAADC rats and a significant decline in striatal dopamine turnover. The serum L-DOPA level correlated with the magnitude of circling behavior in AAV2-hAADC rats. Additionally, AADC activity in homogenates of lesioned striata transduced by AAV2-AADC was 10-fold higher when compared with AAV2-GFP-treated control striata, confirming functional transduction. Our data suggests that the pharmacological regulation of circulating L-DOPA might be effective in the

  5. Design of inverters for the PHOTONERGY project

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-08-01

    The PHOTONERGY project (the former SolcelleInverter project) was initiated on the 1st of September 2001, with a state-of-the-art analysis, which concluded into specifications. Based on this 23 topologies were analyzed in for efficiencies. The results from this analysis was five candidates which all showed a somewhat good efficiency. These five topologies were in further investigated by means of an initial design-iteration and simulations. Two different solutions were picked up in due to their high efficiency and low cost. 1. The standard full-bridge phase shifted DC/DC converter together with a standard DC/AC inverter, 2. A modified version of the novel Shimizu topology. A patent is pending on this modified version. These two inverters are in this document developed and made ready for prototyping. This includes design and selection of reactive- and switching-components, e.g. filter- and bulk-capacitors, low- and high-frequency inductors, high frequency transformers, MOSFETs and diodes. The design of auxiliary circuits is also included, e.g. gate drivers for the MOSFETs, measuring circuits for the grid-current and -voltage, PV-module-current and voltage, protection circuits, hardware near controllers and finally a switch mode power supply. However, the design of the various controllers, except the hardware near PV-current controller for the full bridge phase shifted converter, is not documented in this report but will come later on. This includes all controllers, e.g. maximum power point tracking for the PV-module, utility grid current controller, DC-link voltage controller, phase locked loops, and detection of islanding operation. All of these control loops are to be implemented in a micro-controller. (au)

  6. Multilayer control for inverters in parallel operation without signal interconnection

    DEFF Research Database (Denmark)

    Hua, Ming; Hu, Haibing; Xing, Yan

    2011-01-01

    A multilayer control is proposed for inverters with wireless parallel operation in this paper. The control is embedded in every inverter respectively and consists of three layers. The first layer is based on an improved droop method, which shares the active and reactive power in each module...... by adjusting the phase and amplitude of the output voltage respectively. The second layer is to compensate the droop voltage caused by the droop control and thus improve the load regulation performance of the inverter. The third layer limits the phase deviation between the inverter and the shared ac bus...... in order to ensure all the paralleled inverters keeping in phase. The operational principle and implementation are analyzed in details. A prototype, configured by two paralleled inverters, is set up. Experimental results verify the validity of the proposed control....

  7. The influence of rAAV2-mediated SOX2 delivery into neonatal and adult human RPE cells; a comparative study.

    Science.gov (United States)

    Ezati, Razie; Etemadzadeh, Azadeh; Soheili, Zahra-Soheila; Samiei, Shahram; Ranaei Pirmardan, Ehsan; Davari, Malihe; Najafabadi, Hoda Shams

    2018-02-01

    Cell replacement is a promising therapy for degenerative diseases like age-related macular degeneration (AMD). Since the human retina lacks regeneration capacity, much attention has been directed toward persuading for cells that can differentiate into retinal neurons. In this report, we have investigated reprogramming of the human RPE cells and concerned the effect of donor age on the cellular fate as a critical determinant in reprogramming competence. We evaluated the effect of SOX2 over-expression in human neonatal and adult RPE cells in cultures. The coding region of human SOX2 gene was cloned into adeno-associated virus (AAV2) and primary culture of human neonatal/adult RPE cells were infected by recombinant virus. De-differentiation of RPE to neural/retinal progenitor cells was investigated by quantitative real-time PCR and ICC for neural/retinal progenitor cells' markers. Gene expression analysis showed 80-fold and 12-fold over-expression for SOX2 gene in infected neonatal and adult hRPE cells, respectively. The fold of increase for Nestin in neonatal and adult hRPE cells was 3.8-fold and 2.5-fold, respectively. PAX6 expression was increased threefold and 2.5-fold in neonatal/adult treated cultures. Howbeit, we could not detect rhodopsin, and CHX10 expression in neonatal hRPE cultures and expression of rhodopsin in adult hRPE cells. Results showed SOX2 induced human neonatal/adult RPE cells to de-differentiate toward retinal progenitor cells. However, the increased number of PAX6, CHX10, Thy1, and rhodopsin positive cells in adult hRPE treated cultures clearly indicated the considerable generation of neuro-retinal terminally differentiated cells. © 2017 Wiley Periodicals, Inc.

  8. The mirror map for invertible LG models

    OpenAIRE

    Kreuzer, M

    1994-01-01

    Calculating the (a,c) ring of the maximal phase orbifold for `invertible' Landau--Ginzburg models, we show that the Berglund--H"ubsch construction works for all potentials of the relevant type. The map that sends a monomial in the original model to a twisted state in the orbifold representation of the mirror is constructed explicitly. Via this map, the OP selection rules of the chiral ring exactly correspond to the twist selection rules for the orbifold. This shows that we indeed arrive at th...

  9. On the invertibility of elementary operators

    OpenAIRE

    Boudi, Nadia; Bračič, Janko

    2013-01-01

    Let $\\mathscr{X}$ be a complex Banach space and $\\mathcal{L}(\\mathscr{X})$ be the algebra of all bounded linear operators on $\\mathscr{X}$. For a given elementary operator $\\Phi$ of length $2$ on $\\mathcal{L}(\\mathscr{X})$, we determine necessary and sufficient conditions for the existence of a solution of the equation ${\\rm X} \\Phi=0$ in the algebra of all elementary operators on $\\mathcal{L}(\\mathscr{X})$. Our approach allows us to characterize some invertible elementary operators of length...

  10. Magnetically Coupled Impedance-Source Inverters

    DEFF Research Database (Denmark)

    Loh, Poh Chiang; Blaabjerg, Frede

    2013-01-01

    input-to-output gain and the presence of an impedance network. The former means a high dc-link voltage, which can stress the semiconductor switches unnecessarily. The latter leads to increases in cost and size, which similarly are undesirable. To lessen these concerns, an interesting approach is to use...... magnetically coupled transformers or inductors to raise the gain and modulation ratio simultaneously, while reducing the number of passive components needed. A study of the approach is now presented to show how various existing magnetically coupled inverters can be derived by applying a generic methodology...

  11. Using Inverted Indices for Accelerating LINGO Calculations

    DEFF Research Database (Denmark)

    Kristensen, Thomas Greve; Nielsen, Jesper; Pedersen, Christian Nørgaard Storm

    2011-01-01

    queries. The previous best method for rapidly calculating the LINGOsim similarity matrix required specialised hardware to yield a significant speedup over existing methods. By representing LINGO multisets in the verbose representation and using inverted indices it is possible to calculate LINGOsim......The ever growing size of chemical data bases calls for the development of novel methods for representing and comparing molecules. One such method called LINGO is based on fragmenting the SMILES string representation of molecules. Comparison of molecules can then be performed by calculating...

  12. Nonlinear Feedback Control of the Rotary Inverted Pendulum

    Science.gov (United States)

    2017-06-01

    pendulum include wheeled mobile robots, which can be useful for personal mobility . C. PRIOR WORK There are nonlinear control techniques that have...results. Among the applications of the inverted pendulum is a two wheeled robot. One mobile inverted pendulum robot was created by Grasser, D’Arrigo... pendulum which could shift the weight of the load to keep the pendulum straight up when on a slope [10]. The work in mobile inverted pendulums can

  13. Hawaiian Electric Advanced Inverter Test Plan - Result Summary

    Energy Technology Data Exchange (ETDEWEB)

    Hoke, Anderson; Nelson, Austin; Prabakar, Kumaraguru; Nagarajan, Adarsh

    2016-10-14

    This presentation is intended to share the results of lab testing of five PV inverters with the Hawaiian Electric Companies and other stakeholders and interested parties. The tests included baseline testing of advanced inverter grid support functions, as well as distribution circuit-level tests to examine the impact of the PV inverters on simulated distribution feeders using power hardware-in-the-loop (PHIL) techniques. hardware-in-the-loop (PHIL) techniques.

  14. Preclinical safety evaluation of a recombinant AAV8 vector for X-linked retinoschisis after intravitreal administration in rabbits.

    Science.gov (United States)

    Marangoni, Dario; Wu, Zhijian; Wiley, Henry E; Zeiss, Caroline J; Vijayasarathy, Camasamudram; Zeng, Yong; Hiriyanna, Suja; Bush, Ronald A; Wei, Lisa L; Colosi, Peter; Sieving, Paul A

    2014-12-01

    X-linked retinoschisis (XLRS) is a retinal disease caused by mutations in the gene encoding the protein retinoschisin (RS1) and one of the most common causes of macular degeneration in young men. Currently, no FDA-approved treatments are available for XLRS and a replacement gene therapy could provide a promising strategy. We have developed a novel gene therapy approach for XLRS, based on the administration of AAV8-scRS/IRBPhRS, an adeno-associated viral vector coding the human RS1 protein, via the intravitreal route. On the basis of our prior study in an Rs1-KO mouse, this construct transduces efficiently all the retinal layers, resulting in an RS1 expression similar to that observed in the wild-type and improving retinal structure and function. In support of a clinical trial, we carried out a study to evaluate the ocular safety of intravitreal administration of AAV8-scRS/IRBPhRS into 39 New Zealand White rabbits. Two dose levels of vector, 2e(10) and 2e(11) vector genomes per eye (vg/eye), were tested and ocular inflammation was monitored over a 12-week period by serial ophthalmological and histopathological analysis. A mild ocular inflammatory reaction, consisting mainly of vitreous infiltrates, was observed within 4 weeks from injection, in both 2e(10) and 2e(11) vg/eye groups and was likely driven by the AAV8 capsid. At 12-week follow-up, ophthalmological examination revealed no clinical signs of vitreitis in either of the dose groups. However, while vitreous inflammatory infiltrate was significantly reduced in the 2e(10) vg/eye group at 12 weeks, some rabbits in the higher dose group still showed persistence of inflammatory cells, histologically. In conclusion, intravitreal administration of AAV8-scRS/IRBPhRS into the rabbit eye produces a mild and transient intraocular inflammation that resolves, at a 2e(10) vg/eye dose, within 3 months, and does not cause irreversible tissue damages. These data support the initiation of a clinical trial of intravitreal

  15. Integral inverter/battery charger for use in electric vehicles

    Science.gov (United States)

    Thimmesch, D.

    1983-01-01

    The design and test results of a thyristor based inverter/charger are discussed. A battery charger is included integral to the inverter by using a subset of the inverter power circuit components. The resulting charger provides electrical isolation between the vehicle propulsion battery and ac line and is capable of charging a 25 kWh propulsion battery in 8 hours from a 220 volt ac line. The integral charger employs the inverter commutation components at a resonant ac/dc isolated converter rated at 3.6 kW. Charger efficiency and power factor at an output power of 3.6 kW are 86% and 95% respectively. The inverter, when operated with a matching polyphase ac induction motor and nominal 132 volt propulsion battery, can provide a peak shaft power of 34 kW (45 ph) during motoring operation and 45 kW (60 hp) during regeneration. Thyristors are employed for the inverter power switching devices and are arranged in an input-commutated topology. This configuration requires only two thyristors to commutate the six main inverter thyristors. Inverter efficiency during motoring operation at motor shaft speeds above 450 rad/sec (4300 rpm) is 92-94% for output power levels above 11 KW (15 hp). The combined ac inverter/charger package weighs 47 kg (103 lbs).

  16. A new Zero Voltage Switching three-level NPC inverter

    DEFF Research Database (Denmark)

    He, Ning; Chen, Yenan; Xu, Dehong

    2015-01-01

    A novel Zero Voltage Switching (ZVS) three-level NPC inverter topology using a new ZVS Space Vector Modulation (SVM) scheme is proposed. A detailed operation analysis of ZVS three-level NPC inverter is given. The ZVS condition of the proposed ZVS inverter is derived and it can be achieved of all...... switches in the proposed inverter, which include both the main switches and the auxiliary switches. The design of resonant circuits parameters is also provided. Finally the proposed circuit and ZVS SVM scheme are verified by experimental results and demonstrate a superior performance....

  17. Advanced DC/AC inverters applications in renewable energy

    CERN Document Server

    Luo, Fang Lin

    2013-01-01

    DC/AC inversion technology is of vital importance for industrial applications, including electrical vehicles and renewable energy systems, which require a large number of inverters. In recent years, inversion technology has developed rapidly, with new topologies improving the power factor and increasing power efficiency. Proposing many novel approaches, Advanced DC/AC Inverters: Applications in Renewable Energy describes advanced DC/AC inverters that can be used for renewable energy systems. The book introduces more than 100 topologies of advanced inverters originally developed by the authors,

  18. Optimized Pulse Width Modulation for transformerless active-NPC inverters

    DEFF Research Database (Denmark)

    Achilladelis, Nikolaos; Koutroulis, Eftichios; Blaabjerg, Frede

    2014-01-01

    The transformerless DC/AC inverter topologies are employed in Photovoltaic systems in order to improve the power conversion efficiency, power density and cost. The Active-Neutral Point Clamped (Active-NPC) transformerless inverters have the advantage of achieving better thermal balance among...... their power semiconductors. In this paper, a new modulation technique is proposed for optimally controlling the power switches employed in transformerless Active-NPC inverters. The design results demonstrate that compared to the existing PWM strategies, using the proposed method results in lower total power...... losses and significantly better distribution of the power losses among the semiconductors of the Active-NPC inverter....

  19. Organizational Relationship Termination Competence

    DEFF Research Database (Denmark)

    Ritter, Thomas; Geersbro, Jens

    2011-01-01

    Most firms are involved in a number of customer relationships that drain the firm's resources. However, many firms are hesitant to address this problem. This paper investigates customer relationship termination at the organizational level. We develop and analyze the organizational dimensions...... that a firm's percentage of unwanted customers decreases significantly as acceptance of termination increases, if the firm's definition of unwanted customers is well understood, and if a firm has clear termination routines. In addition, general focus on profitability and external constraints on relationship...... termination are found to significantly affect a firm's relationship termination competence. The findings suggest that managers should regard termination as a legitimate option in customer relationship management. In order to decrease the number of unwanted customers, managers must accept termination...

  20. Inverted face processing in body dysmorphic disorder.

    Science.gov (United States)

    Feusner, Jamie D; Moller, Hayley; Altstein, Lily; Sugar, Catherine; Bookheimer, Susan; Yoon, Joanne; Hembacher, Emily

    2010-11-01

    Individuals with body dysmorphic disorder (BDD) are preoccupied with perceived defects in appearance. Preliminary evidence suggests abnormalities in global and local visual information processing. The objective of this study was to compare global and local processing in BDD subjects and healthy controls by testing the face inversion effect, in which inverted (upside-down) faces are recognized more slowly and less accurately relative to upright faces. Eighteen medication-free subjects with BDD and 17 matched, healthy controls performed a recognition task with sets of upright and inverted faces on a computer screen that were either presented for short duration (500 ms) or long duration (5000 ms). Response time and accuracy rates were analyzed using linear and logistic mixed effects models, respectively. Results indicated that the inversion effect for response time was smaller in BDD subjects than controls during the long duration stimuli, but was not significantly different during the short duration stimuli. Inversion effect on accuracy rates did not differ significantly between groups during either of the two durations. Lesser inversion effect in BDD subjects may be due to greater detail-oriented and piecemeal processing for long duration stimuli. Similar results between groups for short duration stimuli suggest that they may be normally engaging configural and holistic processing for brief presentations. Abnormal visual information processing in BDD may contribute to distorted perception of appearance; this may not be limited to their own faces, but to others' faces as well. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. INVERTING ORTHOTOPIC ILEOCYSTOPLASTY FOR SHORT MESENTERY

    Directory of Open Access Journals (Sweden)

    V. A. Perepechay

    2010-01-01

    Full Text Available During orthotopic ileocystoplasty, the short mesentery causes an increase in the risk of incompetence of anastomosis of the reservoir with the urethra. Inverting orthotopic ileocystoplasty ensures a free reservoir pull-through into the small pelvis and eliminates tissue tension in the anastomosis. The proposed procedure differs from the Studer operation in that the reservoir is sutured lengthwise, after which it is inverted between the mesenteric leaves. The posterior reservoir wall is anteverted and freely brought out into the small pelvis. This reduces the distance to the urethral stump by 3-4 cm. This procedure was used in 19 patients to be operated on. There were no cases of reservoir or reservoir-urethral anastomotic incompetence. The mean neocystic capacity was 110, 350, and 490 ml 0, 3, and 12 months, respectively, after urethral catheter removal. The maximum reservoir pressure does not exceed 40 (mean 30 cm H2O. Daytime urinary retention was 94.7%; nocturnal urinary retention during forced nocturnal miction was 79%. The obtained functional results compare well with those achieved during the similar procedures.

  2. INVERTING ORTHOTOPIC ILEOCYSTOPLASTY FOR SHORT MESENTERY

    Directory of Open Access Journals (Sweden)

    V. A. Perepechay

    2014-07-01

    Full Text Available During orthotopic ileocystoplasty, the short mesentery causes an increase in the risk of incompetence of anastomosis of the reservoir with the urethra. Inverting orthotopic ileocystoplasty ensures a free reservoir pull-through into the small pelvis and eliminates tissue tension in the anastomosis. The proposed procedure differs from the Studer operation in that the reservoir is sutured lengthwise, after which it is inverted between the mesenteric leaves. The posterior reservoir wall is anteverted and freely brought out into the small pelvis. This reduces the distance to the urethral stump by 3-4 cm. This procedure was used in 19 patients to be operated on. There were no cases of reservoir or reservoir-urethral anastomotic incompetence. The mean neocystic capacity was 110, 350, and 490 ml 0, 3, and 12 months, respectively, after urethral catheter removal. The maximum reservoir pressure does not exceed 40 (mean 30 cm H2O. Daytime urinary retention was 94.7%; nocturnal urinary retention during forced nocturnal miction was 79%. The obtained functional results compare well with those achieved during the similar procedures.

  3. Inverting dedevelopment: geometric singularity theory in embryology

    Science.gov (United States)

    Bookstein, Fred L.; Smith, Bradley R.

    2000-10-01

    The diffeomorphism model so useful in the biomathematics of normal morphological variability and disease is inappropriate for applications in embryogenesis, where whole coordinate patches are created out of single points. For this application we need a suitable algebra for the creation of something from nothing in a carefully organized geometry: a formalism for parameterizing discrete nondifferentiabilities of invertible functions on Rk, k $GTR 1. One easy way to begin is via the inverse of the development map - call it the dedevelopment map, the deformation backwards in time. Extrapolated, this map will inevitably have singularities at which its derivative is zero. When the dedevelopment map is inverted to face forward in time, the singularities become appropriately isolated infinities of derivative. We have recently introduced growth visualizations via extrapolations to the isolated singularities at which only one directional derivative is zero. Maps inverse to these create new coordinate patches directionally rather than radically. The most generic singularity that suits this purpose is the crease f(x,y) equals (x,x2y+y3), which has already been applied in morphometrics for the description of focal morphogenetic phenomena. We apply it to embryogenesis in the form of its analytic inverse, and demonstrate its power using a priceless new data set of mouse embryos imaged in 3D by micro-MR with voxels smaller than 100micrometers 3.

  4. Aalborg Inverter - A New Type of “Buck in Buck, Boost in Boost” Grid-Tied Inverter

    DEFF Research Database (Denmark)

    Wu, Weimin; Ji, Junhao; Blaabjerg, Frede

    2015-01-01

    This paper presents a new family of high efficiency dc/ac grid-tied inverter with a wide variation of input dc voltage. It is a “boost in boost, buck in buck” inverter, meaning that only one power stage works at high frequency in order to achieve minimum switching loss. The minimum voltage drop...... is larger than the magnitude of the ac voltage, it is a voltage-source inverter, and on the contrary it is current-source inverter in the other mode. A 220 V/50 Hz/ 2000 W prototype has been constructed. Simulations and experiments show that it has a good control and system performance....

  5. Systemic Errors in Quantitative Polymerase Chain Reaction Titration of Self-Complementary Adeno-Associated Viral Vectors and Improved Alternative Methods

    Science.gov (United States)

    Fagone, Paolo; Wright, J. Fraser; Nathwani, Amit C.; Nienhuis, Arthur W.; Davidoff, Andrew M.

    2012-01-01

    Abstract Self-complementary AAV (scAAV) vector genomes contain a covalently closed hairpin derived from a mutated inverted terminal repeat that connects the two monomer single-stranded genomes into a head-to-head or tail-to-tail dimer. We found that during quantitative PCR (qPCR) this structure inhibits the amplification of proximal amplicons and causes the systemic underreporting of copy number by as much as 10-fold. We show that cleavage of scAAV vector genomes with restriction endonuclease to liberate amplicons from the covalently closed terminal hairpin restores quantitative amplification, and we implement this procedure in a simple, modified qPCR titration method for scAAV vectors. In addition, we developed and present an AAV genome titration procedure based on gel electrophoresis that requires minimal sample processing and has low interassay variability, and as such is well suited for the rigorous quality control demands of clinical vector production facilities. PMID:22428975

  6. Sine-wave three phase resonance inverter for operation of ...

    African Journals Online (AJOL)

    naeema

    conventional and simple solution to this requirement are in the following [8]. Using conventional H-bridge inverter beside of a step-up transformer. Using a renewable energy source with sufficiently large output voltage, which may be realized by a string of series connected modules followed by an H-bridge inverter [12], [13].

  7. Human Mobile Inverted Pendulum Transporter - a Mechatronic System Case Study

    DEFF Research Database (Denmark)

    Bech, Michael Møller; Hansen, Anders Hedegaard; Pedersen, Henrik C.

    2011-01-01

    , which nevertheless illustrates the potentials of unifying classical engineering technologies (mechanics, electronics, control systems) with modern high-efficient inverter-fed permanent magnet AC motors and the latest MEMS sensor technology. A full-scale fully operational prototype of a two-wheel mobile...... inverted pendulum has been built based on the presented design....

  8. Modified impedance source inverter for power conditioning system

    Indian Academy of Sciences (India)

    ... generalized discussion and design of impedance network elements are presented. Comparison with the classical impedance source inverter is presented. Using simulation, analytical results are presented that ensure stability. The proposed voltage type inverter has reduced inrush current at startup, less capacitor voltage ...

  9. Multiple-load series resonant inverter for induction cooking ...

    Indian Academy of Sciences (India)

    P Sharath Kumar

    In addition, it can achieve efficient and stable zero voltage switching operation in the whole load range. The proposed control scheme is simulated and experimentally verified with two-load inverter configuration. Keywords. Induction cooking; multiple load; series resonant inverter; ZVS; pulse density modulation control. 1.

  10. Requirements of inverted roofs with a drainage layer

    DEFF Research Database (Denmark)

    Leimer, Hans-Peter; Rode, Carsten; Künzel, Hartwig

    2005-01-01

    This contribution illustrates the application of the standard EN ISO 6946 regarding the heat loss of an inverted roof for different regions of Europe. An addendum to the standard (EN ISO 6946:1996/A1, 2003) introduces a correction to the thermal transmittance of inverted roofs due to rain water f...

  11. Power system services provided by inverter connected distributed energy resources

    DEFF Research Database (Denmark)

    For the last few years there has been a significant increase of DER units in Denmark, of those units more and more are connected to the power system using inverters. These inverter connected units have the potential to support the electrical power system with various power system services. One...

  12. Three-phase inverter for small high speed motors

    Science.gov (United States)

    Mccormick, John A.; Valenzuela, Javier A.

    1991-01-01

    A high-frequency three-phase inverter is being developed to drive a miniature centrifugal compressor which is a key component in a long-life space-borne cryocooler. The inverter is a unique transformer-coupled design, tailored to the low-voltage high-current characteristic of the compressor's induction motor. The design and performance demonstration of a breadboard model of the inverter are described. The cryocooler uses a reverse-Brayton cycle with turbomachines to provide 5 watt of cooling at 70 K. The design target for input power to the compressor motor is 175 watts. Line-to-neutral phase voltage waveforms to be supplied by the inverter have an amplitude of 15 volt-rms at a frequency of 8 kHz. DC power at 28 volt is supplied to the inverter. The breadboard inverter was tested with a preliminary development model of the compressor. It drove the compressor over a range of operating conditions encompassing frequencies of 5 to 9 kHz at powers of 56 to 437 watt. Inverter efficiencies, calculated from experimentally verified loss models, ranged from 89 to 95 percent over the tests. The design target on efficiency is 90 percent. The inverter was demonstrated to supply starting current adequate to overcome the starting friction of the compressor's self-acting gas bearings by a safe margin.

  13. Three Phase Soft Commutation Auxilary Resonant Pole Inverter

    OpenAIRE

    Vaclav Sladecek

    2006-01-01

    This paper covers the circuit modification of the power part of the inverter with auxiliary resonant poles utilising configuration of switches realised with routinely produced IGBT modules. Covered is also the control optimisation which goal is the minimisation of switching of the auxiliary resonant pole. Presented results were gained on a prototype of an inverter laboratory sample.

  14. Trans-Z-source Neutral Point Clamped inverter

    DEFF Research Database (Denmark)

    Mo, W.; Loh, P. C.; Li, D.

    2012-01-01

    for buck-boost energy conversion with all the favourable advantages of multi-level switching retained. This paper presents three-level trans-Z-source Neutral Point Clamped (NPC) inverter topology, which achieves both the advantages of trans-Z-source and three-level NPC inverter configuration. With proper...

  15. Five-level Z-source diode-clamped inverter

    DEFF Research Database (Denmark)

    Gao, F.; Loh, Poh Chiang; Blaabjerg, Frede

    2010-01-01

    This study proposes a five-level Z-source diode-clamped inverter designed with two intermediate Z-source networks connected between the dc input sources and rear-end inverter circuitry. By partially shorting the Z-source networks, new operating states not previously reported for two-level Z...

  16. Improving generalized inverted index lock wait times

    Science.gov (United States)

    Borodin, A.; Mirvoda, S.; Porshnev, S.; Ponomareva, O.

    2018-01-01

    Concurrent operations on tree like data structures is a cornerstone of any database system. Concurrent operations intended for improving read\\write performance and usually implemented via some way of locking. Deadlock-free methods of concurrency control are known as tree locking protocols. These protocols provide basic operations(verbs) and algorithm (ways of operation invocations) for applying it to any tree-like data structure. These algorithms operate on data, managed by storage engine which are very different among RDBMS implementations. In this paper, we discuss tree locking protocol implementation for General inverted index (Gin) applied to multiversion concurrency control (MVCC) storage engine inside PostgreSQL RDBMS. After that we introduce improvements to locking protocol and provide usage statistics about evaluation of our improvement in very high load environment in one of the world’s largest IT company.

  17. Modifications to Battery chargers and inverters Units

    International Nuclear Information System (INIS)

    Raison, Florent

    2015-01-01

    Over-exceeding the seismic specifications of the nuclear industry has always been the top priority of AEG Power Solutions. Since the Forsmark event, and especially since the Fukushima Daichi accident, utilities have reviewed their specifications. As a consequence, safety related battery chargers and inverters have to withstand higher acceleration levels. Simulation, design and test procedures are key drivers of the battery charger and inverter industry. Forces analysis through simulation is the first step of the product design process. The CAD drawings of our equipment, including the mechanical frame of the cabinet and the internal components, are used for the simulation of vibration. In the frame of 10 Hz, most new specifications show higher values, with higher constraints on our equipment. Our nuclear product range has been adapted to these new requirements. PCBs (Printed Circuit Boards), as key components in charge of the regulation and monitoring of the load, are first separately tested during the design phase, as a specific component. They are subjected to the following tests: Critical load analysis, Thermal imaging, Climatic test, Vibration and shock test. Then the complete equipment will follow a complete test program, including: Type test, EMC test, Seismic test, Aging test. Technology is key in achieving goals in terms of robustness and reliability of battery chargers and inverters. AEG Power Solutions renewed its entire range of products in 2011-2013 and made relevant choices. By updating its complete range of nuclear products, AEG Power Solutions is now offering a new range of solutions to the nuclear industry which minimize the risk of component obsolescence, in case of product replacement on existing nuclear power plants, or of new construction. In order to increase the product reliability and to facilitate the qualification programs of the products, the decision was made to offer 100% analogue technology (Software free). The different regulation and

  18. Motion Analysis Based on Invertible Rapid Transform

    Directory of Open Access Journals (Sweden)

    J. Turan

    1999-06-01

    Full Text Available This paper presents the results of a study on the use of invertible rapid transform (IRT for the motion estimation in a sequence of images. Motion estimation algorithms based on the analysis of the matrix of states (produced in the IRT calculation are described. The new method was used experimentally to estimate crowd and traffic motion from the image data sequences captured at railway stations and at high ways in large cities. The motion vectors may be used to devise a polar plot (showing velocity magnitude and direction for moving objects where the dominant motion tendency can be seen. The experimental results of comparison of the new motion estimation methods with other well known block matching methods (full search, 2D-log, method based on conventional (cross correlation (CC function or phase correlation (PC function for application of crowd motion estimation are also presented.

  19. On Invertible Sampling and Adaptive Security

    DEFF Research Database (Denmark)

    Ishai, Yuval; Kumarasubramanian, Abishek; Orlandi, Claudio

    2011-01-01

    Secure multiparty computation (MPC) is one of the most general and well studied problems in cryptography. We focus on MPC protocols that are required to be secure even when the adversary can adaptively corrupt parties during the protocol, and under the assumption that honest parties cannot reliably...... erase their secrets prior to corruption. Previous feasibility results for adaptively secure MPC in this setting applied either to deterministic functionalities or to randomized functionalities which satisfy a certain technical requirement. The question whether adaptive security is possible for all...... functionalities was left open. We provide the first convincing evidence that the answer to this question is negative, namely that some (randomized) functionalities cannot be realized with adaptive security. We obtain this result by studying the following related invertible sampling problem: given an efficient...

  20. Scalar field cosmologies with inverted potentials

    International Nuclear Information System (INIS)

    Boisseau, B.; Giacomini, H.; Polarski, D.

    2015-01-01

    Regular bouncing solutions in the framework of a scalar-tensor gravity model were found in a recent work. We reconsider the problem in the Einstein frame (EF) in the present work. Singularities arising at the limit of physical viability of the model in the Jordan frame (JF) are either of the Big Bang or of the Big Crunch type in the EF. As a result we obtain integrable scalar field cosmological models in general relativity (GR) with inverted double-well potentials unbounded from below which possess solutions regular in the future, tending to a de Sitter space, and starting with a Big Bang. The existence of the two fixed points for the field dynamics at late times found earlier in the JF becomes transparent in the EF

  1. Scalar field cosmologies with inverted potentials

    Energy Technology Data Exchange (ETDEWEB)

    Boisseau, B.; Giacomini, H. [Université de Tours, Laboratoire de Mathématiques et Physique Théorique, CNRS/UMR 7350, 37200 Tours (France); Polarski, D., E-mail: bruno.boisseau@lmpt.univ-tours.fr, E-mail: hector.giacomini@lmpt.univ-tours.fr, E-mail: david.polarski@umontpellier.fr [Université Montpellier and CNRS, Laboratoire Charles Coulomb, UMR 5221, F-34095 Montpellier (France)

    2015-10-01

    Regular bouncing solutions in the framework of a scalar-tensor gravity model were found in a recent work. We reconsider the problem in the Einstein frame (EF) in the present work. Singularities arising at the limit of physical viability of the model in the Jordan frame (JF) are either of the Big Bang or of the Big Crunch type in the EF. As a result we obtain integrable scalar field cosmological models in general relativity (GR) with inverted double-well potentials unbounded from below which possess solutions regular in the future, tending to a de Sitter space, and starting with a Big Bang. The existence of the two fixed points for the field dynamics at late times found earlier in the JF becomes transparent in the EF.

  2. Analytical modeling of inverted annular film boiling

    International Nuclear Information System (INIS)

    Analytis, G.T.; Yadigaroglu, G.

    1987-01-01

    By employing a two-fluid formulation similar to the one used in the most recent LWR accident analysis codes, a model for the Inverted Annular Film Boiling region is developed. The conservation equations, together with appropriate closure relations are solved numerically. Successful comparisons are made between model predictions and heat transfer coefficient distributions measured in a series of single-tube reflooding experiments. Generally, the model predicts correctly the dependence of the heat transfer coefficient on liquid subcooling and flow rate; for some cases, however, heat transfer is still under-predicted, and an enhancement of the heat exchange from the liquid-vapour interface to the bulk of the liquid is required. The importance of the initial conditions at the quench front is also discussed. (orig.)

  3. Analytical modeling of inverted annular film boiling

    International Nuclear Information System (INIS)

    Analytis, G.T.; Yadigaroglu, G.

    1985-01-01

    By employing a two-fluid formulation similar to the one used in the most recent LWR accident analysis codes, a model for the Inverted Annular Film Boiling region is developed. The conservation equations, together with appropriate constitutive relations are solved numerically and successful comparisons are made between model predictions and heat transfer coefficient distributions measured in a series of single-tube reflooding experiments. The model predicts generally correctly the dependence of the heat transfer coefficient on liquid subcooling and flow rate, through, for some cases, heat transfer is still under-predicted, and an enhancement of the heat exchange from the liquid-vapour interface to the bulk of the liquid is required

  4. CONTAINER TERMINALS IN EUROPE

    Directory of Open Access Journals (Sweden)

    Bart W. WIEGMANS

    2001-01-01

    Full Text Available This paper aims to address the linkage between logistics (in particular, the management of marketing channel flows and transport markets, while also the interaction between these two markets and intermodal container terminals is analysed. The marketing channel theory is used to describe all relevant actors and flows that run through marketing channels, starting with customer needs and ending with customer satisfaction. Porter's theory of competitive advantages is used to review competitive forces in both markets. Finally, a competitor analysis is performed for the logistics and transport market. These theories are applied so as to be able to determine the competitive position of intermodal container terminals with a view to the management of marketing channel flows and the physical transport of freight flows. Hence, the central question of this paper is: Which markets are served by intermodal container terminals and with whom are they competing? At present, neither the maritime container terminals nor the continental container terminals appear to have a significant influence in the logistics service market; they concentrate mainly on the physical movement of containers (transshipment. Furthermore, maritime container terminals and continental container terminals are not dominant players in the transport service market. Our conclusion is that continental terminals are predominantly competing with unimodal road transport, with neighbouring continental terminals and with barge transport companies.

  5. Transistorized PWM inverter-induction motor drive system

    Science.gov (United States)

    Peak, S. C.; Plunkett, A. B.

    1982-01-01

    This paper describes the development of a transistorized PWM inverter-induction motor traction drive system. A vehicle performance analysis was performed to establish the vehicle tractive effort-speed requirements. These requirements were then converted into a set of inverter and motor specifications. The inverter was a transistorized three-phase bridge using General Electric power Darlington transistors. The description of the design and development of this inverter is the principal object of this paper. The high-speed induction motor is a design which is optimized for use with an inverter power source. The primary feedback control is a torque angle control with voltage and torque outer loop controls. A current-controlled PWM technique is used to control the motor voltage. The drive has a constant torque output with PWM operation to base motor speed and a constant horsepower output with square wave operation to maximum speed. The drive system was dynamometer tested and the results are presented.

  6. Evaluation of a high power inverter for potential space applications

    Science.gov (United States)

    Guynes, B. V.; Lanier, J. R., Jr.

    1976-01-01

    The ADM-006 inverter discussed utilizes a unique method of using power switching circuits to produce three-phase low harmonic content voltages without any significant filtering. This method is referred to as the power center approach to inverter design and is explained briefly. The results are presented of tests performed by MSFC to evaluate inverter performance, especially when required to provide power to nonlinear loads such as half or full wave rectified loads with capacitive filtering. Test preocedures and results are described. These tests show that the power center inverter essentially met or exceeded all of claims excluding voltage regulation (3.9 percent versus specified 3.3 percent) and would be a good candidate for high power inverter applications such as may be found on Space Station, Spacelab, etc.

  7. Optimal Design of Modern Transformerless PV Inverter Topologies

    DEFF Research Database (Denmark)

    Saridakis, Stefanos; Koutroulis, Eftichios; Blaabjerg, Frede

    2013-01-01

    The design optimization of H5, H6, neutral point clamped, active-neutral point clamped, and conergy-NPC transformerless photovoltaic (PV) inverters is presented in this paper. The components reliability in terms of the corresponding malfunctions, affecting the PV inverter maintenance cost during...... the operational lifetime period of the PV installation, is also considered in the optimization process. According to the results of the proposed design method, different optimal values of the PV inverter design variables are derived for each PV inverter topology and installation site. The H5, H6, neutral point...... clamped, active-neutral point clamped and conergy-NPC PV inverters designed using the proposed optimization process feature lower levelized cost of generated electricity and lifetime cost, longer mean time between failures and inject more PV-generated energy into the electric grid than their nonoptimized...

  8. Adderall induced inverted-Takotsubo cardiomyopathy.

    Science.gov (United States)

    Alsidawi, Said; Muth, James; Wilkin, James

    2011-11-15

    Takotsubo Cardiomyopathy (TTC), also known as stress-induced cardiomyopathy, was initially described in Japan in 1990. Both illicit and prescription drugs have added to the growing list of insulting stressors. We describe an interesting case of atypical TTC triggered by adderall overdose. A 19-year-old female was brought to the Emergency Department after ingesting 30 Adderall tablets. She was complaining of pressure like chest pain and shortness of breath. Her cardiac enzymes were elevated but the electrocardiogram was unremarkable. Echocardiography identified an ejection fraction (EF) of 25-30% with severe hypokinesis of the base and a preserved apex. Cardiac angiography demonstrated normal coronary arteries with an EF of 35%, hyperkinetic apex and akinetic base consistent with the diagnosis of inverted-TTC. Her symptoms resolved in 24 hrs. Repeat echocardiogram performed 3 days later showed an EF of 60% with no regional wall motion abnormalities. TTC can be identified as a rapid development of severe and reversible left ventricular dysfunction extending beyond the territory of a single epicardial coronary artery in the absence of coronary artery disease or pheochromocytoma. Clinical presentation can be challenging and very hard to distinguish from acute myocardial infarction. Medication induced-TTC has been reported. In our case, the patient overdosed on Adderall which is a sympathomimetic medication. Cardiac imaging identified wall motion abnormalities consistent with inverted type TTC. Restoration of left ventricular function within days confirms the diagnosis of TTC. In conclusion, this case offers an interesting insight into the pathophysiology of TTC. Copyright © 2011 Wiley Periodicals, Inc.

  9. Transformerless Photovoltaic Inverters Connected to the Grid

    DEFF Research Database (Denmark)

    Kerekes, Tamas; Teodorescu, Remus; Borup, Uffe

    2007-01-01

    -phase with respect to the leakage current generation. The best results, both for single-phase and three-phase systems, are obtained when the middle point of the input capacitors is connected to the neutral point, thereby minimizing the voltage fluctuations present at the terminals of the PV panel....

  10. An Optimal Current Controller Design for a Grid Connected Inverter to Improve Power Quality and Test Commercial PV Inverters

    Directory of Open Access Journals (Sweden)

    Ali Algaddafi

    2017-01-01

    Full Text Available Grid connected inverters play a crucial role in generating energy to be fed to the grid. A filter is commonly used to suppress the switching frequency harmonics produced by the inverter, this being passive, and either an L- or LCL-filter. The latter is smaller in size compared to the L-filter. But choosing the optimal values of the LCL-filter is challenging due to resonance, which can affect stability. This paper presents a simple inverter controller design with an L-filter. The control topology is simple and applied easily using traditional control theory. Fast Fourier Transform analysis is used to compare different grid connected inverter control topologies. The modelled grid connected inverter with the proposed controller complies with the IEEE-1547 standard, and total harmonic distortion of the output current of the modelled inverter has been just 0.25% with an improved output waveform. Experimental work on a commercial PV inverter is then presented, including the effect of strong and weak grid connection. Inverter effects on the resistive load connected at the point of common coupling are presented. Results show that the voltage and current of resistive load, when the grid is interrupted, are increased, which may cause failure or damage for connecting appliances.

  11. An Optimal Current Controller Design for a Grid Connected Inverter to Improve Power Quality and Test Commercial PV Inverters.

    Science.gov (United States)

    Algaddafi, Ali; Altuwayjiri, Saud A; Ahmed, Oday A; Daho, Ibrahim

    2017-01-01

    Grid connected inverters play a crucial role in generating energy to be fed to the grid. A filter is commonly used to suppress the switching frequency harmonics produced by the inverter, this being passive, and either an L- or LCL-filter. The latter is smaller in size compared to the L-filter. But choosing the optimal values of the LCL-filter is challenging due to resonance, which can affect stability. This paper presents a simple inverter controller design with an L-filter. The control topology is simple and applied easily using traditional control theory. Fast Fourier Transform analysis is used to compare different grid connected inverter control topologies. The modelled grid connected inverter with the proposed controller complies with the IEEE-1547 standard, and total harmonic distortion of the output current of the modelled inverter has been just 0.25% with an improved output waveform. Experimental work on a commercial PV inverter is then presented, including the effect of strong and weak grid connection. Inverter effects on the resistive load connected at the point of common coupling are presented. Results show that the voltage and current of resistive load, when the grid is interrupted, are increased, which may cause failure or damage for connecting appliances.

  12. An Optimal Current Controller Design for a Grid Connected Inverter to Improve Power Quality and Test Commercial PV Inverters

    Science.gov (United States)

    Altuwayjiri, Saud A.; Ahmed, Oday A.; Daho, Ibrahim

    2017-01-01

    Grid connected inverters play a crucial role in generating energy to be fed to the grid. A filter is commonly used to suppress the switching frequency harmonics produced by the inverter, this being passive, and either an L- or LCL-filter. The latter is smaller in size compared to the L-filter. But choosing the optimal values of the LCL-filter is challenging due to resonance, which can affect stability. This paper presents a simple inverter controller design with an L-filter. The control topology is simple and applied easily using traditional control theory. Fast Fourier Transform analysis is used to compare different grid connected inverter control topologies. The modelled grid connected inverter with the proposed controller complies with the IEEE-1547 standard, and total harmonic distortion of the output current of the modelled inverter has been just 0.25% with an improved output waveform. Experimental work on a commercial PV inverter is then presented, including the effect of strong and weak grid connection. Inverter effects on the resistive load connected at the point of common coupling are presented. Results show that the voltage and current of resistive load, when the grid is interrupted, are increased, which may cause failure or damage for connecting appliances. PMID:28540362

  13. The AAV-mediated and RNA-guided CRISPR/Cas9 system for gene therapy of DMD and BMD.

    Science.gov (United States)

    Wang, Jing-Zhang; Wu, Peng; Shi, Zhi-Min; Xu, Yan-Li; Liu, Zhi-Jun

    2017-08-01

    Mutations in the dystrophin gene (Dmd) result in Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD), which afflict many newborn boys. In 2016, Brain and Development published several interesting articles on DMD treatment with antisense oligonucleotide, kinase inhibitor, and prednisolone. Even more strikingly, three articles in the issue 6271 of Science in 2016 provide new insights into gene therapy of DMD and BMD via the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9). In brief, adeno-associated virus (AAV) vectors transport guided RNAs (gRNAs) and Cas9 into mdx mouse model, gRNAs recognize the mutated Dmd exon 23 (having a stop codon), and Cas9 cut the mutated exon 23 off the Dmd gene. These manipulations restored expression of truncated but partially functional dystrophin, improved skeletal and cardiac muscle function, and increased survival of mdx mice significantly. This review concisely summarized the related advancements and discussed their primary implications in the future gene therapy of DMD, including AAV-vector selection, gRNA designing, Cas9 optimization, dystrophin-restoration efficiency, administration routes, and systemic and long-term therapeutic efficacy. Future orientations, including off-target effects, safety concerns, immune responses, precision medicine, and Dmd-editing in the brain (potentially blocked by the blood-brain barrier) were also elucidated briefly. Collectively, the AAV-mediated and RNA-guided CRISPR/Cas9 system has major superiorities compared with traditional gene therapy, and might contribute to the treatment of DMD and BMD substantially in the near future. Copyright © 2017 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  14. Experimental Evaluation of PV Inverter Anti-Islanding with Grid Support Functions in Multi-Inverter Island Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Hoke, Anderson [National Renewable Energy Lab. (NREL), Golden, CO (United States); Nelson, Austin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Miller, Brian [National Renewable Energy Lab. (NREL), Golden, CO (United States); Chakraborty, Sudipta [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bell, Frances [SolarCity, San Mateo, CA (United States); McCarty, Michael [SolarCity, San Mateo, CA (United States)

    2016-07-01

    As PV and other DER systems are connected to the grid at increased penetration levels, island detection may become more challenging for two reasons: 1.) In islands containing many DERs, active inverter-based anti-islanding methods may have more difficulty detecting islands because each individual inverter's efforts to detect the island may be interfered with by the other inverters in the island. 2.) The increasing numbers of DERs are leading to new requirements that DERs ride through grid disturbances and even actively try to regulate grid voltage and frequency back towards nominal operating conditions. These new grid support requirements may directly or indirectly interfere with anti-islanding controls. This report describes a series of tests designed to examine the impacts of both grid support functions and multi-inverter islands on anti-islanding effectiveness. Crucially, the multi-inverter anti-islanding tests described in this report examine scenarios with multiple inverters connected to multiple different points on the grid. While this so-called 'solar subdivision' scenario has been examined to some extent through simulation, this is the first known work to test it using hardware inverters. This was accomplished through the use of power hardware-in-the-loop (PHIL) simulation, which allows the hardware inverters to be connected to a real-time transient simulation of an electric power system that can be easily reconfigured to test various distribution circuit scenarios. The anti-islanding test design was a modified version of the unintentional islanding test in IEEE Standard 1547.1, which creates a balanced, resonant island with the intent of creating a highly challenging condition for island detection. Three common, commercially available single-phase PV inverters from three different manufacturers were tested. The first part of this work examined each inverter individually using a series of pure hardware resistive-inductive-capacitive (RLC

  15. A gene therapy of experimental parkinsonism monkeys with intra-striatums implantation of AAV-TH with CT guiding

    International Nuclear Information System (INIS)

    Wang Wei; Mao Jun; Yu Xiaoping; Liu Sheng; Hu Weixin; Zeng Zhaojun; Cai Weijun; Wu Xiaobing

    2003-01-01

    Objective: To observe the transfection ability to neuron and the therapy effect of adeno-associated virus vector (AAV) mediated intracerebral expressing of human tyrosine hydroxylase (TH) in the Rhesus monkey of Parkinson disease with CT guiding. Methods: Six Rhesus monkeys were induced into hemi-parkinsonism models by infusion of MPTP into right internal carotid artery. Under the guidance of CT and stereotactic apparatus, the recombinant adeno-associated virus vectors-human tyrosine hydroxylase were injected into the right caudate nucleus of 5 PD monkeys. The motor ability of the PD model was evaluated for 6 months after implantation. The content of DA, DOPAC, and HVA in the caudate nucleus was assayed with HPLC, and the expression of the tyrosine hydroxylase gene was detected with immunohistochemistry and RT-PCR. Results: The method of stereotactic puncture guided with CT had the features of real-time operating, fine location, and mini-trauma. The motor ability of all five models was all ameliorated after stereotactical injection of AAV-hTH vectors from two weeks up to six months. One PD monkey did not show any twist in response to apomorphine test. The frequency of twirl in the other 4 PD monkeys in response to apomorphine test was decreased by 42%-70% compared with that preoperatively. The contents of DA and DA metabolites in the lesion caudate nucleus were increased. Many TH positive cells in the implantation sites of caudate nucleus were shown by immunohistochemistry, which was different from the contralateral caudate nucleus. TH-mRNA was found in the treated side of caudate nucleus with RT-PCR, but no positive detection in the untreated side of caudate nucleus or in other sites in the brain. The negative results of RT-PCR were also shown in samples of the heart, liver, kidney tissue, or right side caudate nucleus of the uninjected monkey. Conclusion: Under the guidance of CT and stereotactic apparatus, the AAV-hTH vector can be injected accurately into the

  16. Mappings of terminal continua

    Directory of Open Access Journals (Sweden)

    Janusz J. Charatonik

    2002-01-01

    Full Text Available The concept of a terminal continuum introduced in 1973 by G. R. Gordh Jr., for hereditarily unicoherent continua is extended to arbitrary continua. Mapping properties of these two concepts are investigated. Especially the invariance of terminality under mappings satisfying some special conditions is studied. In particular, we conclude that the invariance holds for atomic mappings.

  17. Managing terminal restlessness

    African Journals Online (AJOL)

    Repro

    compounded by the memory of unre- lieved suffering. ... progressive impairment of memory, judge- ment and thinking. ... of palliative sedation for refractory symp- toms in dying patients. Managing terminal restlessness. Terminal restlessness presents many challenges, not least recognition of the problem and its. c a u s e s .

  18. Electric machine and current source inverter drive system

    Science.gov (United States)

    Hsu, John S

    2014-06-24

    A drive system includes an electric machine and a current source inverter (CSI). This integration of an electric machine and an inverter uses the machine's field excitation coil for not only flux generation in the machine but also for the CSI inductor. This integration of the two technologies, namely the U machine motor and the CSI, opens a new chapter for the component function integration instead of the traditional integration by simply placing separate machine and inverter components in the same housing. Elimination of the CSI inductor adds to the CSI volumetric reduction of the capacitors and the elimination of PMs for the motor further improve the drive system cost, weight, and volume.

  19. Intelligence Controller for STATCOM Using Cascaded Multilevel Inverter

    Directory of Open Access Journals (Sweden)

    C. C. Asir Rajan

    2010-01-01

    Full Text Available This paper presents a special gating pattern swapping technique for cascaded multilevel inverter, which is used for STATCOM.By using this technique besides minimizing the harmonic level, the inverter unit fundamental output voltages areequalized. Therefore, all the inverter units in each phase leg can equally share the exchanged active and reactive powerwith the utility grid. This greatly helps the dc-link voltages balancing control. PI Control is employed for improving performance.Fuzzy control is employed to the system for enhancing transient stability. The performance is analyzed usingdigital simulation.

  20. Asymmetrical and symmetrical embedded Z-source inverters

    DEFF Research Database (Denmark)

    Gao, F.; Loh, P.C.; Li, D.

    2011-01-01

    This study presents two types of embedded Z-source inverters with each type further divided into asymmetrical and symmetrical realisations. Being different from their traditional counterparts, the presented inverters have their dc sources inserted within their X-shaped impedance networks so...... ends, which indirectly translates to a lowering of overall system cost. These noted advantages are indeed appropriate for applications like photovoltaic and fuel cell energy harnessing, and have already been confirmed in simulation and experimentally using a laboratory-implemented inverter prototype....

  1. Flash Welding Control by Use of PWM Inverter Power Supply

    Science.gov (United States)

    Nagura, Kouki; Sato, Yukihiko; Yamamura, Naoki; Ishida, Muneaki

    The flash welding is characterized by the high quality, the high production efficiency and the large sectional area welding, and is used to weld rails and hot coils in shop welding mainly. In order to realize high accuracy and high response control of flash welding, the inverter technology has been applied to flash welding in this study. In this paper, a method of process control combined with inverter flash control and mechanical control is proposed. Experiment results of the proposed process control combined with inverter flash control and mechanical control are presented.

  2. Component-Minimized Buck-Boost Voltage Source Inverters

    DEFF Research Database (Denmark)

    Gao, F.; Loh, P.C.; Blaabjerg, Frede

    2007-01-01

    . In order to form a distinct neutral potential in the corresponding voltage boost circuitry for correct B4 inverter operation, necessary modifications are derived step by step. The resulted dc networks with symmetrical placement of passive components allow complete charging and equal energy distribution...... semiconductors. Besides the advantage of reduced active components, buck-boost B4 inverters use a little more passive components when compared with buck-boost B6 inverters, which would allow a selectable tradeoff in practice. Moreover, analysis for discontinuous conduction mode of inductor current reveals...

  3. Power Inverter Topologies for Photovoltaic Modules - A Review

    DEFF Research Database (Denmark)

    Kjær, Søren Bækhøj; Pedersen, John Kim; Blaabjerg, Frede

    2002-01-01

    This review-paper focuses on the latest development of inverters for photovoltaic AC-Modules. The power range for these inverters is usually within 90 Watt to 500 Watt, which covers the most commercial photovoltaic-modules. Self-commutated inverters have replaced the grid-commutated ones. The same...... is true for the bulky low-frequency transformers versus the high-frequency transformers, which are used to adapt the voltage level. The AC-Module provides a modular design and a flexible behaviour in various grid conditions. It hereby opens the market for photovoltaic-power for everyone at a low cost due...

  4. Discontinuous interleaving of parallel inverters for efficiency improvement

    DEFF Research Database (Denmark)

    Rannestad, Bjørn; Munk-Nielsen, Stig; Gadgaard, Kristian

    2017-01-01

    Interleaved switching of parallel inverters has previously been proposed for efficiency/size improvements of grid connected three-phase inverters. This paper proposes a novel interleaving method which practically eliminates insulated gate bipolar transistor (IGBT) turn-on losses and drastically...... reduces diode reverse recovery losses. The reduction in switching losses are obtained by interleaving two parallel inverter branches so that only one branch conducts the load current at a time. By placing saturable inductors between the parallel branches, soft switching may be obtained, and thereby...

  5. Closed-loop waveform control of boost inverter

    DEFF Research Database (Denmark)

    Zhu, Guo Rong; Xiao, Cheng Yuan; Wang, Haoran

    2016-01-01

    The input current of single-phase inverter typically has an AC ripple component at twice the output frequency, which causes a reduction in both the operating lifetime of its DC source and the efficiency of the system. In this paper, the closed-loop performance of a proposed waveform control method...... to eliminate such a ripple current in boost inverter is investigated. The small-signal stability and the dynamic characteristic of the inverter system for input voltage or wide range load variations under the closed-loop waveform control method are studied. It is validated that with the closedloop waveform...

  6. Ground Fault Overvoltage With Inverter-Interfaced Distributed Energy Resources

    Energy Technology Data Exchange (ETDEWEB)

    Ropp, Michael; Hoke, Anderson; Chakraborty, Sudipta; Schutz, Dustin; Mouw, Chris; Nelson, Austin; McCarty, Michael; Wang, Trudie; Sorenson, Adam

    2017-04-01

    Ground Fault Overvoltage can occur in situations in which a four-wire distribution circuit is energized by an ungrounded voltage source during a single phase to ground fault. The phenomenon is well-documented with ungrounded synchronous machines, but there is considerable discussion about whether inverters cause this phenomenon, and consequently whether inverters require effective grounding. This paper examines the overvoltages that can be supported by inverters during single phase to ground faults via theory, simulation and experiment, identifies the relevant physical mechanisms, quantifies expected levels of overvoltage, and makes recommendations for optimal mitigation.

  7. A PWM transistor inverter for an ac electric vehicle drive

    Science.gov (United States)

    Slicker, J. M.

    1981-01-01

    A prototype system consisting of closely integrated motor, inverter, and transaxle has been built in order to demonstrate the feasibility of a three-phase ac transistorized inverter for electric vehicle applications. The microprocessor-controlled inverter employs monolithic power transistors to drive an oil-cooled, three-phase induction traction motor at a peak output power of 30 kW from a 144 V battery pack. Transistor safe switching requirements are discussed, and a circuit is presented for recovering trapped snubber inductor energy at transistor turn-off.

  8. LCCT-derived three-level three-phase inverters

    DEFF Research Database (Denmark)

    Shults, Tatiana; Husev, Oleksandr; Blaabjerg, Frede

    2017-01-01

    Solutions for a family of the novel three-level neutral-point-clamped (NPC) inductor-capacitor-capacitor-transformer (LCCT)-derived three-phase inverters are described and compared. Component design guidelines and steady state analysis, current and voltage waveforms are given. The authors......' simulation results confirm the theoretical predictions. It was found that an asymmetrical three-level NPC LCCT-derived inverter with a single diode in the impedance source network is the most promising solution. Experimental results for an asymmetrical three-level NPC LCCT-derived inverter with a single...

  9. An iterative method to invert the LTSn matrix

    Energy Technology Data Exchange (ETDEWEB)

    Cardona, A.V.; Vilhena, M.T. de [UFRGS, Porto Alegre (Brazil)

    1996-12-31

    Recently Vilhena and Barichello proposed the LTSn method to solve, analytically, the Discrete Ordinates Problem (Sn problem) in transport theory. The main feature of this method consist in the application of the Laplace transform to the set of Sn equations and solve the resulting algebraic system for the transport flux. Barichello solve the linear system containing the parameter s applying the definition of matrix invertion exploiting the structure of the LTSn matrix. In this work, it is proposed a new scheme to invert the LTSn matrix, decomposing it in blocks and recursively inverting this blocks.

  10. Self-splicing of a group IIC intron: 5? exon recognition and alternative 5? splicing events implicate the stem?loop motif of a transcriptional terminator

    OpenAIRE

    Toor, Navtej; Robart, Aaron R.; Christianson, Joshua; Zimmerly, Steven

    2006-01-01

    Bacterial IIC introns are a newly recognized subclass of group II introns whose ribozyme properties have not been characterized in detail. IIC introns are typically located downstream of transcriptional terminator motifs (inverted repeat followed by T's) or other inverted repeats in bacterial genomes. Here we have characterized the self-splicing activity of a IIC intron, B.h.I1, from Bacillus halodurans. B.h.I1 self-splices in vitro through hydrolysis to produce linear intron, but interesting...

  11. CNS-directed AAV2-mediated gene therapy ameliorates functional deficits in a murine model of infantile neuronal ceroid lipofuscinosis.

    Science.gov (United States)

    Griffey, Megan A; Wozniak, David; Wong, Michael; Bible, Ellen; Johnson, Kendra; Rothman, Steven M; Wentz, Annie E; Cooper, Jonathan D; Sands, Mark S

    2006-03-01

    The neuronal ceroid lipofuscinoses (Batten disease) are a group of inherited neurodegenerative diseases characterized by the progressive intralysosomal accumulation of autofluorescent material in many cells, visual defects, seizures, cognitive deficits, and premature death. Infantile neuronal ceroid lipofuscinosis (INCL) has the earliest onset ( approximately 1.5 years of age) and is caused by a deficiency in the lysosomal enzyme palmitoyl protein thioesterase-1 (PPT1). Currently there is no effective treatment for children with INCL. In this study, newborn PPT1-deficient mice received two (cortex), four (cortex and hippocampus), or six (cortex, hippocampus, and cerebellum) bilateral intracranial injections of AAV2-PPT1. The AAV-treated animals had localized increases in PPT1 activity, decreased autofluorescent material, improved histologic parameters, and increased brain mass. In addition, the treated animals had dose-dependent improvements in a battery of behavioral tests and improved interictal electroencephalographic tracings. However, there was neither a significant decrease in seizure frequency nor an increase in longevity even in INCL animals receiving six injections. These data suggest that early treatment of INCL using gene transfer techniques can be efficacious. However, higher levels or a broader distribution of PPT1 expression, or both, will be required for more complete correction of this neurodegenerative disease.

  12. Cell-type specific oxytocin gene expression from AAV delivered promoter deletion constructs into the rat supraoptic nucleus in vivo.

    Directory of Open Access Journals (Sweden)

    Raymond L Fields

    Full Text Available The magnocellular neurons (MCNs in the hypothalamus selectively express either oxytocin (OXT or vasopressin (AVP neuropeptide genes, a property that defines their phenotypes. Here we examine the molecular basis of this selectivity in the OXT MCNs by stereotaxic microinjections of adeno-associated virus (AAV vectors that contain various OXT gene promoter deletion constructs using EGFP as the reporter into the rat supraoptic nucleus (SON. Two weeks following injection of the AAVs, immunohistochemical assays of EGFP expression from these constructs were done to determine whether the EGFP reporter co-localizes with either the OXT- or AVP-immunoreactivity in the MCNs. The results show that the key elements in the OT gene promoter that regulate the cell-type specific expression the SON are located -216 to -100 bp upstream of the transcription start site. We hypothesize that within this 116 bp domain a repressor exists that inhibits expression specifically in AVP MCNs, thereby leading to the cell-type specific expression of the OXT gene only in the OXT MCNs.

  13. Protective Role of rAAV-NDI1, Serotype 5, in an Acute MPTP Mouse Parkinson's Model

    Directory of Open Access Journals (Sweden)

    Jennifer Barber-Singh

    2011-01-01

    Full Text Available Defects in mitochondrial proton-translocating NADH-quinone oxidoreductase (complex I have been implicated in a number of acquired and hereditary diseases including Leigh's syndrome and more recently Parkinson's disease. A limited number of strategies have been attempted to repair the damaged complex I with little or no success. We have recently shown that the non-proton-pumping, internal NADH-ubiquinone oxidoreductase (Ndi1 from Saccharomyces cerevisiae (baker's yeast can be successfully inserted into the mitochondria of mice and rats, and the enzyme was found to be fully active. Using recombinant adenoassociated virus vectors (serotype 5 carrying our NDI1 gene, we were able to express the Ndi1 protein in the substantia nigra (SN of C57BL/6 mice with an expression period of two months. The results show that the AAV serotype 5 was highly efficient in expressing Ndi1 in the SN, when compared to a previous model using serotype 2, which led to nearly 100% protection when using an acute MPTP model. It is conceivable that the AAV-serotype5 carrying the NDI1 gene is a powerful tool for proof-of-concept study to demonstrate complex I defects as the causable factor in diseases of the brain.

  14. High efficiency of BRCA1 knockout using rAAV-mediated gene targeting: developing a pig model for breast cancer.

    Science.gov (United States)

    Luo, Yonglun; Li, Juan; Liu, Ying; Lin, Lin; Du, Yutao; Li, Shengting; Yang, Huanming; Vajta, Gábor; Callesen, Henrik; Bolund, Lars; Sørensen, Charlotte Brandt

    2011-10-01

    Germline inactivating mutations of the breast cancer associated gene 1 (BRCA1) predispose to breast cancer and account for most cases of familiar breast and/or ovarian cancer. The pig is an excellent model for medical research as well as testing of new methods and drugs for disease prevention and treatment. We have generated cloned BRCA1 knockout (KO) Yucatan miniature piglets by targeting exon 11 using recombinant adeno-associated virus (rAAV)-mediated gene targeting and somatic cell nuclear transfer by Handmade Cloning (HMC). We found a very high targeting rate of rAAV-mediated BRCA1 KO. Approximately 35% of the selected cells were BRCA1 targeted. One BRCA1 KO cell clone (5D1), identified by PCR and Southern blot, was used as nuclear donor for HMC. Reconstructed embryos were transferred to three recipient sows which gave birth to 8 piglets in total. Genotyping identified seven piglets as BRCA1 heterozygotes (BRCA1(+/∆11)), and one as wild type. The BRCA1 expression was decreased at the mRNA level in BRCA1(+/∆11) fibroblasts. However, all BRCA1(+/∆11) piglets died within 18 days after birth. The causes of perinatal mortality remain unclear. Possible explanations may include a combination of the BRCA1 haploinsufficiency, problems of epigenetic reprogramming, presence of the marker gene, single cell clone effects, and/or the special genetic background of the minipigs.

  15. Nonleaking battery terminals.

    Science.gov (United States)

    Snider, W. E.; Nagle, W. J.

    1972-01-01

    Three different terminals were designed for usage in a 40 ampere/hour silver zinc battery which has a 45% KOH by weight electrolyte in a plastic battery case. Life tests, including thermal cycling, electrical charge and discharge for up to three years duration, were conducted on these three different terminal designs. Tests for creep rate and tensile strength were conducted on the polyphenylene oxide plastic battery cases. Some cases were unused and others containing KOH electrolyte were placed on life tests. The design and testing of nonleaking battery terminals for use with a KOH electrolyte in a plastic case are considered.

  16. Comsat's TDMA traffic terminal

    Science.gov (United States)

    Benjamin, M. C.; Bogaert, W. M.

    1985-06-01

    Comsat has installed two traffic terminals in the Etam earth-station and is currently installing a third in the new Roaring Creek earth-station to access the Intelsat TDMA network. This paper describes the Comsat TDMA traffic terminal equipment from the supergroup interface to the antenna. Comsat's 1: N redundancy approach for terrestrial interface equipment and DSI unit back-up is described as well as electrical path length, amplitude and group delay equalization techniques, special on-line RF monitoring and failure reporting facilities and the operation and maintenance center which can operate and perform diagnostic testing on up to four traffic terminals from a central location.

  17. Pathologic Collision of Inverted Papilloma with Esthesioneuroblastoma

    Directory of Open Access Journals (Sweden)

    Sana D Karam

    2014-03-01

    Full Text Available Background: Inverted papilloma (IP of the nasal cavity is a benign tumor that 0.5-4% of all nasal tumors and have been known to rarely undergo malignant transformation to squamous carcinoma an even more rarely adenocarcinoma. Synchronous association with low grade esthesioneuroblastoma (ENB has been reported in only one case report where a small sized lesion was treated with surgery alone. Here we report the first case of invasion of IP by high grade ENB with nodal metastasis that was treated with combined modality therapy.Case Presentation: A case of a 64 year-old African American gentleman presented to the otolaryngology with a three-month history of recurrent epistaxis. Imaging revealed a large right nasal cavity mass extending into the right sphenoid sinus but without intracranial extension. Surgical pathology revealed high grade ENB invading IP. An orbitofrontal craniotomy approach was used to achieve complete resection of the mass but with positive margins. Postoperative PET/CT showed nodal metastasis. The patient was then treated with adjuvant chemoradiation and remains without evidence of disease at 42 months post-treatment. We discuss the disease presentation, histopathologic features, and disease management with literature support.Conclusion: In this very rare disease presentation where two extremely rare malignancies collide, we show that aggressive management with trimodality therapy of surgery, adjuvant radiation with stereotactic radiosurgical boost, and adjuvant chemotherapy gives excellent results. Given the natural history of the disease, however, long follow up is needed to declare complete freedom from the disease.

  18. Inverted Leidenfrost-like Effect during Condensation.

    Science.gov (United States)

    Narhe, Ramchandra; Anand, Sushant; Rykaczewski, Konrad; Medici, Marie-Gabrielle; González-Viñas, Wenceslao; Varanasi, Kripa K; Beysens, Daniel

    2015-05-19

    Water droplets condensing on solidified phase change materials such as benzene and cyclohexane near their melting point show in-plane jumping and continuous "crawling" motion. The jumping drop motion has been tentatively explained as an outcome of melting and refreezing of the materials surface beneath the droplets and can be thus considered as an inverted Leidenfrost-like effect (in the classical case vapor is generated from a droplet on a hot substrate). We present here a detailed investigation of jumping movements using high-speed imaging and static cross-sectional cryogenic focused ion beam scanning electron microscope imaging. Our results show that drop motion is induced by a thermocapillary (Marangoni) effect. The in-plane jumping motion can be delineated to occur in two stages. The first stage occurs on a millisecond time scale and comprises melting the substrate due to drop condensation. This results in droplet depinning, partial spreading, and thermocapillary movement until freezing of the cyclohexane film. The second stage occurs on a second time scale and comprises relaxation motion of the drop contact line (change in drop contact radius and contact angle) after substrate freezing. When the cyclohexane film cannot freeze, the droplet continuously glides on the surface, resulting in the crawling motion.

  19. Inverted Lymphoglandular Polyp in Descending Colon

    Directory of Open Access Journals (Sweden)

    Shengmei Zhou

    2015-01-01

    Full Text Available A 47-year-old male with a history of left colon cancer, status post left colon resection for 12 years, presented with rectal bleeding. Colonoscopic examination revealed an 8 mm sessile polyp in the proximal descending colon. Microscopic examination showed that the surface of this polyp was covered with a layer of normal colonic mucosa with focal surface erosion. In the submucosal layer, an intimate admixture of multiple cystically dilated glands and prominent lymphoid aggregates with germinal centers was seen. The glands were lined by columnar epithelium. Immunohistochemical staining showed the glands were positive for CK20 and CDX2 and negative for CK7, with a low proliferative index, mostly consistent with reactive colonic glands. The patient remained asymptomatic after one-year follow-up. A review of the literature shows very rare descriptions of similar lesions, but none fits exactly this pattern. We would designate this inverted lymphoglandular polyp and present this case to raise the awareness of recognizing this unusual histological entity.

  20. Inverted Metamorphic Multijunction (IMM) Cell Processing Instructions

    Energy Technology Data Exchange (ETDEWEB)

    Duda, A.; Ward, S.; Young, M.

    2012-02-01

    This technical report details the processing schedule used to fabricate Inverted Metamorphic Multijunction (IMM) concentrator solar cells at The National Renewable Energy Laboratory (NREL). These devices are used as experimental test structures to support the research at NREL that is focused on increasing the efficiency of photovoltaic power conversion. They are not intended to be devices suitable for deployment in working concentrator systems primarily because of heat sinking issues. The process schedule was developed to be compatible with small sample sizes and to afford relatively rapid turn-around times, in support of research efforts. The report describes the use of electro deposition of gold for both the back and front contacts. Electro-deposition is used because of its rapid turn around time and because it is a benign metallization technique that is seldom responsible for damage to the semiconductors. The layer transfer technique is detailed including the use of a commercially available adhesive and the etching away of the parent gallium arsenide substrate. Photolithography is used to define front contact grids as well as the mesa area of the cell. Finally, the selective wet chemical etchant system is introduced and its use to reveal the back contact is described.

  1. An Optimal Current Controller Design for a Grid Connected Inverter to Improve Power Quality and Test Commercial PV Inverters

    OpenAIRE

    Algaddafi, Ali; Altuwayjiri, Saud A.; Ahmed, Oday A.; Daho, Ibrahim

    2017-01-01

    Grid connected inverters play a crucial role in generating energy to be fed to the grid. A filter is commonly used to suppress the switching frequency harmonics produced by the inverter, this being passive, and either an L- or LCL-filter. The latter is smaller in size compared to the L-filter. But choosing the optimal values of the LCL-filter is challenging due to resonance, which can affect stability. This paper presents a simple inverter controller design with an L-filter. The control topol...

  2. High Radiation Resistance Inverted Metamorphic Solar Cell, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation in this SBIR Phase II project is the development of a unique triple junction inverted metamorphic technology (IMM), which will enable the...

  3. Multilayer Control for Inverters in Parallel Operation without Intercommunications

    DEFF Research Database (Denmark)

    Hua, Ming; Hu, Haibing; Xing, Yan

    2012-01-01

    In this paper, a multilayer control is proposed for inverters able to operate in parallel without intercommunications. The first control layer is an improved droop method that introduces power proportional terms into the conventional droop scheme, letting both active and reactive power to be shared...... among the inverters. The second layer is designed to compensate the voltage deviations caused by the mentioned droop control, thus improving the load-voltage regulation of the system. The third layer is a quasi-synchronization control aiming to roughly adjust the angle of the inverter to be close...... to the common ac bus. This layer ensures that the phase difference of each inverter inside a limited margin with the help of the phase signal sensed from the common ac bus. The principle of operation of the control scheme has been analyzed in detail. A small-signal model has been developed in order to study...

  4. Robustness analysis of the efficiency in PV inverters

    DEFF Research Database (Denmark)

    Pigazo, Alberto; Liserre, Marco; Blaabjerg, Frede

    2013-01-01

    During last years an increasing attention has been paid to the efficiency of grid-connected PV inverters. They are manufactured from a number of discrete components and by using a certain topology and control strategy. Hence, the performance of a certain PV inverter not only depends on the selected...... topology and control strategy but also on the characteristics of the employed components. The aim of this paper is evaluate the effect of physical variations associated to the main components on the overall efficiency of PV inverters. It is concluded that a statistical evaluation of the power converter...... provides a better understanding of the PV inverter performance and, in this sense, the definition of the European Efficiency must be reviewed in order to show the quality of the manufactured product....

  5. Study of Inverted Pendulum Robot Using Fuzzy Servo Control Method

    Directory of Open Access Journals (Sweden)

    Dazhong Wang

    2012-09-01

    Full Text Available The inverted pendulum robot is a classical problem in controls. The inherit instabilities in the setup make it a natural target for a control system. Inverted pendulum robot is suitable to use for investigation and verification of various control methods for dynamic systems. Maintaining an equilibrium position of the pendulum pointing up is a challenge as this equilibrium position is unstable. As the inverted pendulum robot system is nonlinear it is well-suited to be controlled by fuzzy logic. In this paper, Lagrange method has been applied to develop the mathematical model of the system. The objective of the simulation to be shown using the fuzzy control method can stabilize the nonlinear system of inverted pendulum robot.

  6. Improving Advanced Inverter Control Convergence in Distribution Power Flow

    Energy Technology Data Exchange (ETDEWEB)

    Nagarajan, Adarsh; Palmintier, Bryan; Ding, Fei; Mather, Barry; Baggu, Murali

    2016-11-21

    Simulation of modern distribution system powerflow increasingly requires capturing the impact of advanced PV inverter voltage regulation on powerflow. With Volt/var control, the inverter adjusts its reactive power flow as a function of the point of common coupling (PCC) voltage. Similarly, Volt/watt control curtails active power production as a function of PCC voltage. However, with larger systems and higher penetrations of PV, this active/reactive power flow itself can cause significant changes to the PCC voltage potentially introducing oscillations that slow the convergence of system simulations. Improper treatment of these advanced inverter functions could potentially lead to incorrect results. This paper explores a simple approach to speed such convergence by blending in the previous iteration's reactive power estimate to dampen these oscillations. Results with a single large (5MW) PV system and with multiple 500kW advanced inverters show dramatic improvements using this approach.

  7. Triple inverter pierce oscillator circuit suitable for CMOS

    Science.gov (United States)

    Wessendorf,; Kurt, O [Albuquerque, NM

    2007-02-27

    An oscillator circuit is disclosed which can be formed using discrete field-effect transistors (FETs), or as a complementary metal-oxide-semiconductor (CMOS) integrated circuit. The oscillator circuit utilizes a Pierce oscillator design with three inverter stages connected in series. A feedback resistor provided in a feedback loop about a second inverter stage provides an almost ideal inverting transconductance thereby allowing high-Q operation at the resonator-controlled frequency while suppressing a parasitic oscillation frequency that is inherent in a Pierce configuration using a "standard" triple inverter for the sustaining amplifier. The oscillator circuit, which operates in a range of 10 50 MHz, has applications for use as a clock in a microprocessor and can also be used for sensor applications.

  8. Multilevel inverter switching controller using a field programmable ...

    African Journals Online (AJOL)

    Conducted simulation and measurement results verified and validated the switching controller design functionality and requirement. Keywords: multilevel inverter, switching controller; FPGA, general purpose processor (GPP);digital signal processing (DSP); IGBT; Verilog, power consumption; harmonic elimination (SHE).

  9. Development, Fabrication, and Testing of Inverter Power System for Metroliner

    Science.gov (United States)

    1979-11-01

    This report documents the development and subsequent fabrication of a solid state auxiliary power conditioning unit (APCU) for the upgraded Metroliner. The APCU is an inverter of the pulse width modulated type having multiple parallel transistors in ...

  10. Diode-Assisted Buck-Boost Voltage-Source Inverters

    DEFF Research Database (Denmark)

    Gao, Feng; Loh, Poh Chiang; Teodorescu, Remus

    2009-01-01

    , a number of diode-assisted inverter variants can be designed with each having its own operational principle and voltage gain expression. For controlling them, a generic modulation scheme that can be used for controlling all diode-assisted variants with minimized harmonic distortion and component stress......This paper proposes a number of diode-assisted buck-boost voltage-source inverters with a unique X-shaped diode-capacitor network inserted between the inverter circuitry and dc source for producing a voltage gain that is comparatively higher than those of other buck-boost conversion techniques....... Using the diode-assisted network, the proposed inverters can naturally configure themselves to perform capacitive charging in parallel and discharging in series to give a higher voltage multiplication factor without compromising waveform quality. In addition, by adopting different front-end circuitries...

  11. Tri-State Current Source Inverter With Improved Dynamic Performance

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Loh, Poh Chiang; Wong, Chow Pang

    2008-01-01

    Traditional dc-ac current source inverter (CSI) has a right-half-plane (RHP) zero in its control-to-output transfer function. This RHP zero causes the inverter output to fall before rising when a step increase in command reference is required (commonly known as non-minimum-phase effect). To achieve...... sequence, the inductive boosting and discharging intervals can be decoupled, allowing the RHP zero to be eliminated with only minor circuit modifications (high level control schemes like predictive and multiloop voltage/current control remain unchanged). The designed inverter can be controlled using...... a better dynamic response, this paper proposes the design of a tri-state CSI using only an additional semiconductor switch for introducing unique freewheeling states to the traditional six active and three null states of a CSI. With the freewheeling states inserted appropriately within the inverter state...

  12. Sideband-Harmonic Instability of Paralleled Inverters with Asynchronous Carriers

    DEFF Research Database (Denmark)

    Yang, Dongsheng; Wang, Xiongfei; Blaabjerg, Frede

    2017-01-01

    Paralleled inverters with asynchronous carriers are increasingly emerging into renewable power plants and other power-electronic-based power systems. The sideband harmonics resulting from the pulse width modulation tend to be different from one inverter to another, which may trigger sideband-harmonic...... resonances among the paralleled inverters. To address the sideband-harmonic instability, the nonlinearity of the digital pulse width modulator is analyzed first in this paper based on the harmonic balance principle. It is revealed that the dynamic sideband components corresponding to a given small......-signal perturbation can be far below the Nyquist frequency, and they may not be effectively attenuated by anti-aliasing filters. A multi-frequency impedance model is then developed for the inverter, which characterizes the dynamic coupling between the perturbed frequency component and the sideband frequency component...

  13. Six transformer based asymmetrical embedded Z-source inverters

    DEFF Research Database (Denmark)

    Wei, Mo; Poh Chiang, Loh; Chi, Jin

    2013-01-01

    Embedded/Asymmetrical embedded Z-source inverters were proposed to maintain smooth input current/voltage across the dc source and within the impedance network, remain the shoot-through feature used to boost up the dc-link voltage without adding bulky filter at input side. This paper introduces a ...... a class of transformer based asymmetrical embedded Z-source inverters which keep the smooth input current and voltage while achieving enhanced voltage boost capability. The presented inverters are verified by laboratory prototypes experimentally.......Embedded/Asymmetrical embedded Z-source inverters were proposed to maintain smooth input current/voltage across the dc source and within the impedance network, remain the shoot-through feature used to boost up the dc-link voltage without adding bulky filter at input side. This paper introduces...

  14. Design optimization of grid-connected PV inverters

    DEFF Research Database (Denmark)

    Koutroulis, Eftichios; Blaabjerg, Frede

    2011-01-01

    The DC/AC inverters are the key elements in grid-connected PV energy production systems. In this paper, new design optimization techniques focused on transformerless (very high efficiency) PV inverters are proposed. They have been developed based on an analysis of the deficiencies of the current......, state-of-the-art PV inverters design technology, which limits the amount of PV energy supplied into the electric grid. The influences of the electric grid regulations and standards and the PV array operational characteristics on the design of grid-connected PV inverters have also been considered....... The simulation results verify that the proposed optimization techniques enable the maximization of the PV energy injected into the electric grid by the optimized PV installation....

  15. High Radiation Resistance Inverted Metamorphic Solar Cell Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation in the proposed SBIR Phase I project is the development of a unique triple unction inverted metamorphic technology (IMM), which will enable the...

  16. An inverter/controller subsystem optimized for photovoltaic applications

    Science.gov (United States)

    Pickrell, R. L.; Merrill, W. C.; Osullivan, G.

    1978-01-01

    Conversion of solar array dc power to ac power stimulated the specification, design, and simulation testing of an inverter/controller subsystem tailored to the photovoltaic power source characteristics. This paper discusses the optimization of the inverter/controller design as part of an overall Photovoltaic Power System (PPS) designed for maximum energy extraction from the solar array. The special design requirements for the inverter/controller include: (1) a power system controller (PSC) to control continuously the solar array operating point at the maximum power level based on variable solar insolation and cell temperatures; and (2) an inverter designed for high efficiency at rated load and low losses at light loadings to conserve energy. It must be capable of operating connected to the utility line at a level set by an external controller (PSC).

  17. Inverted base pavements : new field test and design catalogue.

    Science.gov (United States)

    2014-01-01

    The current economic situation has severely affected the US road infrastructure and funding has become : inadequate for either maintenance or future growth. : The inverted base pavement structure is a promising alternative to achieve high quality roa...

  18. Terminated Multifamily Mortgages Database

    Data.gov (United States)

    Department of Housing and Urban Development — This dataset includes all terminated HUD Multifamily mortgages except those from the Hospital Mortgage Insurance Program. It includes the Holder and Servicer at the...

  19. Resistance Spot Welding with Middelfrequency-Inverter Weling Gun

    DEFF Research Database (Denmark)

    Rasmussen, Mogens H.

    The paper presents the results of investigations concerning the process stability and weldability lobes for uncoated sheets of 1.0 mm thickness when performing resistance spot welding with a middlefrequency-inverter welding gun......The paper presents the results of investigations concerning the process stability and weldability lobes for uncoated sheets of 1.0 mm thickness when performing resistance spot welding with a middlefrequency-inverter welding gun...

  20. Inverter-based circuit design techniques for low supply voltages

    CERN Document Server

    Palani, Rakesh Kumar

    2017-01-01

    This book describes intuitive analog design approaches using digital inverters, providing filter architectures and circuit techniques enabling high performance analog circuit design. The authors provide process, supply voltage and temperature (PVT) variation-tolerant design techniques for inverter based circuits. They also discuss various analog design techniques for lower technology nodes and lower power supply, which can be used for designing high performance systems-on-chip.    .