Efficacy versus health risks: An in vitro evaluation of power-driven scalers.

PubMed

Graetz, Christian; Plaumann, Anna; Bielfeldt, Jule; Tillner, Anica; Sälzer, Sonja; Dörfer, Christof Edmund

2015-01-01

Power-driven instrumentation of root surfaces during supportive periodontal therapy is an alternative to hand instrumentation. The purpose of this pilot in vitro study was to investigate the efficacy of sub- and supragingival plaque removal with a sonic (AIR: Synea, W and H, Bürmoos, Austria) and two ultrasonic devices (TIG: Tigon+, W and H, Bürmoos, Austria; VEC: Vector, Dürr, Bietigheim-Bissingen, Germany) as well as the health-risk for dental professionals during treatment. The power-driven devices were utilized to remove plaque from model teeth in dummy heads. The percentage of residual artificial plaque after 2 min of supra- or subgingival instrumentation was calculated by means of image-processing techniques at four sites (n = 576) of each tooth. The Health-Risk-Index (HRI: spatter/residual plaque quotient) with the different power-driven devices was assessed during treatment. The smallest amounts of residual plaque were found for the sonic device AIR (8.89% ± 10.92%) and the ultrasonic scaler TIG (8.72% ± 12.02%) (P = 0.707). Significantly more plaque was remained after the use of the ultrasonic scaler VEC (18.76% ± 18.07%) (P < 0.001). Irrespectively of the scaler, efficacy was similar sub- (10.7% ± 11.6%) and supragingivally (13.5% ± 17.2%) (P = 0.901). AIR/TIG demonstrated equal residual amounts of plaque sub- (P = 0.831) as well as supragingivally (P = 0.510). However, AIR/VEC and TIG/VEC were significantly in favor of AIR and TIG (P < 0.001). In contrast, the lowest HRI was found after using VEC (0.0043) and differed considerably for AIR (0.2812) and TIG (0.0287). Sonic devices are as effective as ultrasonic devices in the removal of biofilm but bear a higher risk to the dental professional's health concerning the formation of spatter.

Prediction of enhancer-promoter interactions via natural language processing.

PubMed

Zeng, Wanwen; Wu, Mengmeng; Jiang, Rui

2018-05-09

Precise identification of three-dimensional genome organization, especially enhancer-promoter interactions (EPIs), is important to deciphering gene regulation, cell differentiation and disease mechanisms. Currently, it is a challenging task to distinguish true interactions from other nearby non-interacting ones since the power of traditional experimental methods is limited due to low resolution or low throughput. We propose a novel computational framework EP2vec to assay three-dimensional genomic interactions. We first extract sequence embedding features, defined as fixed-length vector representations learned from variable-length sequences using an unsupervised deep learning method in natural language processing. Then, we train a classifier to predict EPIs using the learned representations in supervised way. Experimental results demonstrate that EP2vec obtains F1 scores ranging from 0.841~ 0.933 on different datasets, which outperforms existing methods. We prove the robustness of sequence embedding features by carrying out sensitivity analysis. Besides, we identify motifs that represent cell line-specific information through analysis of the learned sequence embedding features by adopting attention mechanism. Last, we show that even superior performance with F1 scores 0.889~ 0.940 can be achieved by combining sequence embedding features and experimental features. EP2vec sheds light on feature extraction for DNA sequences of arbitrary lengths and provides a powerful approach for EPIs identification.

Physical contact between human vascular endothelial and smooth muscle cells modulates cytosolic and nuclear calcium homeostasis.

PubMed

Hassan, Ghada S; Jacques, Danielle; D'Orléans-Juste, Pedro; Magder, Sheldon; Bkaily, Ghassan

2018-05-14

The interaction between vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs) plays an important role in the modulation of vascular tone. There is, however, no information on whether direct physical communication regulates the intracellular calcium levels of human VECs (hVECs) and (or) human VSMCs (hVSMCs). Thus, the objective of the study is to verify whether co-culture of hVECs and hVSMCs modulates cytosolic ([Ca 2+ ] c ) and nuclear calcium ([Ca 2+ ] n ) levels via physical contact and (or) factors released by both cell types. Quantitative 3D confocal microscopy for [Ca 2+ ] c and [Ca 2+ ] n measurement was performed in cultured hVECs or hVSMCs or in co-culture of hVECs-hVSMCs. Our results show that: (1) physical contact between hVECs-hVECs or hVSMCs-hVSMCs does not affect [Ca 2+ ] c and [Ca 2+ ] n in these 2 cell types; (2) physical contact between hVECs and hVSMCs induces a significant increase only of [Ca 2+ ] n of hVECs without affecting the level of [Ca 2+ ] c and [Ca 2+ ] n of hVSMCs; and (3) preconditioned culture medium of hVECs or hVSMCs does not affect [Ca 2+ ] c and [Ca 2+ ] n of both types of cells. We concluded that physical contact between hVECs and hVSMCs only modulates [Ca 2+ ] n in hVECs. The increase of [Ca 2+ ] n in hVECs may modulate nuclear functions that are calcium dependent.

Cancer cells cause vascular endothelial cell (vEC) retraction via 12(S)HETE secretion; the possible role of cancer cell derived microparticle.

PubMed

Uchide, Keiji; Sakon, Masato; Ariyoshi, Hideo; Nakamori, Syouji; Tokunaga, Masaru; Monden, Morito

2007-02-01

Cancer cell mediated vascular endothelial cell (vEC) retraction plays a pivotal role in cancer metastasis. The aim of this study is to clarify the biochemical character of vEC retraction factor derived from human breast cancer cell line, MCF-7. In order to estimate vEC retracting activity, transwell chamber assay system was employed. We first tested the effects of trypsin digestion as well as lipid extraction of culture medium (CM). Trypsin digestion of CM resulted in approximately 40% loss of vEC retracting activity and lipid extraction of CM by Brigh and Dyer methods recovered approximately 60% of vEC retracting activity, suggesting that approximately 60% of vEC retracting activity in MCF-7 derived CM is due to lipid. Although Nordihydroguaiaretic acid (NDGA), the specific lipoxygenase inhibitor, suppressed vEC retracting activity in CM, Acetyl salicylic acid (ASA), a specific cyclooxygenase inhibitor, did not affect the activity, suggesting that lipid exerting vEC retracting activity in CM belongs to lipoxygenase mediated arachidonate metabolites. Thin layer chromatography clearly demonstrated that Rf value of lipid vEC retracting factor in CM is identical to 12HETE. Authentic 12(S)HETE, but not 12(R)HETE, showed vEC retracting activity. After the ultracentrifugation of CM, most lipid vEC retracting activity was recovered from the pellet fraction, and flow cytometric analysis using specific antibody against 12(S)HETE clearly showed the association of 12(S)HETE with small particle in CM. These findings suggested the principal involvement of 12(S)HETE in cancer cell derived microparticles in cancer cell mediated vEC retraction.

Profiling of kidney vascular endothelial cell plasma membrane proteins by liquid chromatography-tandem mass spectrometry.

PubMed

Liu, Zan; Xu, Bo; Nameta, Masaaki; Zhang, Ying; Magdeldin, Sameh; Yoshida, Yutaka; Yamamoto, Keiko; Fujinaka, Hidehiko; Yaoita, Eishin; Tasaki, Masayuki; Nakagawa, Yuki; Saito, Kazuhide; Takahashi, Kota; Yamamoto, Tadashi

2013-06-01

Vascular endothelial cells (VECs) play crucial roles in physiological and pathologic conditions in tissues and organs. Most of these roles are related to VEC plasma membrane proteins. In the kidney, VECs are closely associated with structures and functions; however, plasma membrane proteins in kidney VECs remain to be fully elucidated. Rat kidneys were perfused with cationic colloidal silica nanoparticles (CCSN) to label the VEC plasma membrane. The CCSN-labeled plasma membrane fraction was collected by gradient ultracentrifugation. The VEC plasma membrane or whole-kidney lysate proteins were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and digested with trypsin in gels for liquid chromatography-tandem mass spectrometry. Enrichment analysis was then performed. The VEC plasma membrane proteins were purified by the CCSN method with high yield (approximately 20 μg from 1 g of rat kidney). By Mascot search, 582 proteins were identified in the VEC plasma membrane fraction, and 1,205 proteins were identified in the kidney lysate. In addition to 16 VEC marker proteins such as integrin beta-1 and intercellular adhesion molecule-2 (ICAM-2), 8 novel proteins such as Deltex 3-like protein and phosphatidylinositol binding clathrin assembly protein (PICALM) were identified. As expected, many key functions of plasma membranes in general and of endothelial cells in particular (i.e., leukocyte adhesion) were significantly overrepresented in the proteome of CCSN-labeled kidney VEC fraction. The CCSN method is a reliable technique for isolation of VEC plasma membrane from the kidney, and proteomic analysis followed by bioinformatics revealed the characteristics of in vivo VECs in the kidney.

Bcl-2 and caspase-3 are major regulators in Agaricus blazei-induced human leukemic U937 cell apoptosis through dephoshorylation of Akt.

PubMed

Jin, Cheng-Yun; Moon, Dong-Oh; Choi, Yung Hyun; Lee, Jae-Dong; Kim, Gi-Young

2007-08-01

Agaricus blazei is a medicinal mushroom that possesses antimetastatic, antitumor, antimutagenic, and immunostimulating effects. However, the molecular mechanisms involved in A. blazei-mediated apoptosis remain unclear. In the present study, to elucidate the role of the Bcl-2 in A. blazei-mediated apoptosis, U937 cells were transfected with either empty vector (U937/vec) or vector containing cDNA encoding full-length Bcl-2 (U937/Bcl-2). As compared with U937/vec, U937/Bcl-2 cells exhibited a 4-fold greater expression of Bcl-2. Treatment of U937/vec with 1.0-4.0 mg/ml of A. blazei extract (ABE) for 24 h resulted in a significant induction of morphologic features indicative of apoptosis. In contrast, U937/Bcl-2 exposed to the same ABE treatment only exhibited a slight induction of apoptotic features. ABE-induced apoptosis was accompanied by downregulation of antiapoptotic proteins such as X-linked inhibitor of apoptosis protein (XIAP), inhibitor of apoptosis protein (cIAP)-2 and Bcl-2, activation of caspase-3, and cleavage of poly(ADP-ribose)polymerase (PARP). Ectopic expression of Bcl-2 was associated with significantly induced expression of antiapoptotic proteins, such as cIAP-2 and Bcl-2, but not XIAP. Ectopic expression of Bcl-2 also reduced caspase-3 activation and PARP cleavage in ABE treated U937 cells. Furthermore, treatment with the caspase-3 inhibitor z-DEVD-fmk was sufficient to restore cell viability following ABE treatment. This increase in viability was ascribed to downregulation of caspase-3 and blockage of PARP and PLC-gamma cleavage. ABE also triggered the downregulation of Akt, and combined treatment with LY294002 (an inhibitor of Akt) significantly decreased cell viability. The results indicated that major regulators of ABE-induced apoptosis in human leukemic U937 cells are Bcl-2 and caspase-3, which are associated with dephosphorylation of the Akt signal pathway.

Tissue factor is an angiogenic-specific receptor for factor VII-targeted immunotherapy and photodynamic therapy.

PubMed

Hu, Zhiwei; Cheng, Jijun; Xu, Jie; Ruf, Wolfram; Lockwood, Charles J

2017-02-01

Identification of target molecules specific for angiogenic vascular endothelial cells (VEC), the inner layer of pathological neovasculature, is critical for discovery and development of neovascular-targeting therapy for angiogenesis-dependent human diseases, notably cancer, macular degeneration and endometriosis, in which vascular endothelial growth factor (VEGF) plays a central pathophysiological role. Using VEGF-stimulated vascular endothelial cells (VECs) isolated from microvessels, venous and arterial blood vessels as in vitro angiogenic models and unstimulated VECs as a quiescent VEC model, we examined the expression of tissue factor (TF), a membrane-bound receptor on the angiogenic VEC models compared with quiescent VEC controls. We found that TF is specifically expressed on angiogenic VECs in a time-dependent manner in microvessels, venous and arterial vessels. TF-targeted therapeutic agents, including factor VII (fVII)-IgG1 Fc and fVII-conjugated photosensitizer, can selectively bind angiogenic VECs, but not the quiescent VECs. Moreover, fVII-targeted photodynamic therapy can selectively and completely eradicate angiogenic VECs. We conclude that TF is an angiogenic-specific receptor and the target molecule for fVII-targeted therapeutics. This study supports clinical trials of TF-targeted therapeutics for the treatment of angiogenesis-dependent diseases such as cancer, macular degeneration and endometriosis.

Pancreatic adenocarcinoma upregulated factor (PAUF) confers resistance to pancreatic cancer cells against oncolytic parvovirus H-1 infection through IFNA receptor-mediated signaling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaowinn, Sirichat; Cho, Il-Rae; Moon, Jeong

2015-04-03

Pancreatic adenocarcinoma upregulated factor (PAUF), a novel oncogene, plays a crucial role in the development of pancreatic cancer, including its metastasis and proliferation. Therefore, PAUF-expressing pancreatic cancer cells could be important targets for oncolytic virus-mediated treatment. Panc-1 cells expressing PAUF (Panc-PAUF) showed relative resistance to parvovirus H-1 infection compared with Panc-1 cells expressing an empty vector (Panc-Vec). Of interest, expression of type I IFN-α receptor (IFNAR) was higher in Panc-PAUF cells than in Panc-Vec cells. Increased expression of IFNAR in turn increased the activation of Stat1 and Tyk2 in Panc-PAUF cells compared with that in Panc-Vec cells. Suppression of Tyk2more » and Stat1, which are important downstream molecules for IFN-α signaling, sensitized pancreatic cancer cells to parvovirus H-1-mediated apoptosis. Further, constitutive suppression of PAUF sensitized Bxpc3 pancreatic cancer cells to parvovirus H-1 infection. Taken together, these results suggested that PAUF conferred resistance to pancreatic cancer cells against oncolytic parvovirus H-1 infection through IFNAR-mediated signaling. - Highlights: • PAUF confers resistance against oncolytic parvovirus H-1 infection. • PAUF enhances the expression of IFNAR in Panc-1 cells. • Increased activation of Tyk2 or Stat1 by PAUF provides resistance to parvovirus H-1-mediated apoptosis. • Constitutive inhibition of PAUF enhances parvovirus H-1-mediated oncolysis of Bxpc3 pancreatic cancer cells.« less

Efficient Direct Reprogramming of Mature Amniotic Cells into Endothelial Cells by ETS Factors and TGFβ Suppression

PubMed Central

Ginsberg, Michael; James, Daylon; Ding, Bi-Sen; Nolan, Daniel; Geng, Fuqiang; Butler, Jason M; Schachterle, William; Pulijaal, Venkat R; Mathew, Susan; Chasen, Stephen T; Xiang, Jenny; Rosenwaks, Zev; Shido, Koji; Elemento, Olivier; Rabbany, Sina Y; Rafii, Shahin

2012-01-01

ETS transcription factors ETV2, FLI1 and ERG1 specify pluripotent stem cells into endothelial cells (ECs). However, these ECs are unstable and drift towards non-vascular cell fates. We show that human mid-gestation c-Kit− lineage-committed amniotic cells (ACs) can be readily reprogrammed into induced vascular endothelial cells (iVECs). Transient ETV2 expression in ACs generated proliferative but immature iVECs, while co-expression with FLI1/ERG1 endowed iVECs with a vascular repertoire and morphology matching mature stable ECs. Brief TGFβ-inhibition functionalized VEGFR2 signaling, augmenting specification of ACs to iVECs. Genome-wide transcriptional analyses showed that iVECs are similar to adult ECs in which vascular-specific genes are turned on and non-vascular genes are silenced. Functionally, iVECs form long-lasting patent vasculature in Matrigel plugs and regenerating livers. Thus, short-term ETV2 expression and TGFβ-inhibition along with constitutive ERG1/FLI1 co-expression reprogram mature ACs into durable and functional iVECs with clinical-scale expansion potential. Public banking of HLA-typed iVECs would establish a vascular inventory for treatment of genetically diverse disorders. PMID:23084400

Adhesive protein interactions with chitosan: consequences for valve endothelial cell growth on tissue-engineering materials.

PubMed

Cuy, Janet L; Beckstead, Benjamin L; Brown, Chad D; Hoffman, Allan S; Giachelli, Cecilia M

2003-11-01

Stable endothelialization of a tissue-engineered heart valve is essential for proper valve function, although adhesive characteristics of the native valve endothelial cell (VEC) have rarely been explored. This research evaluated VEC adhesive qualities and attempted to enhance VEC growth on the biopolymer chitosan, a novel tissue-engineering scaffold material with promising biological and chemical properties. Aortic VEC cultures were isolated and found to preferentially adhere to fibronectin, collagen types IV and I over laminin and osteopontin in a dose-dependent manner. Seeding of VEC onto comparison substrates revealed VEC growth and morphology to be preferential in the order: tissue culture polystyrene > gelatin, poly(DL-lactide-co-glycolide), chitosan > poly(hydroxy alkanoate). Adhesive protein precoating of chitosan did not significantly enhance VEC growth, despite equivalent protein adsorption as to polystyrene. Initial cell adhesion to protein-precoated chitosan, however, was higher than for polystyrene. Composite chitosan/collagen type IV films were investigated as an alternative to simple protein precoatings, and were shown to improve VEC growth and morphology over chitosan alone. These findings suggest potential manipulation of chitosan properties to improve amenability to valve tissue-engineering applications. Copyright 2003 Wiley Periodicals, Inc.

VE-Cadherin–Mediated Epigenetic Regulation of Endothelial Gene Expression

PubMed Central

Morini, Marco F.; Giampietro, Costanza; Corada, Monica; Pisati, Federica; Lavarone, Elisa; Cunha, Sara I.; Conze, Lei L.; O’Reilly, Nicola; Joshi, Dhira; Kjaer, Svend; George, Roger; Nye, Emma; Ma, Anqi; Jin, Jian; Mitter, Richard; Lupia, Michela; Cavallaro, Ugo; Pasini, Diego; Calado, Dinis P.

2018-01-01

Rationale: The mechanistic foundation of vascular maturation is still largely unknown. Several human pathologies are characterized by deregulated angiogenesis and unstable blood vessels. Solid tumors, for instance, get their nourishment from newly formed structurally abnormal vessels which present wide and irregular interendothelial junctions. Expression and clustering of the main endothelial-specific adherens junction protein, VEC (vascular endothelial cadherin), upregulate genes with key roles in endothelial differentiation and stability. Objective: We aim at understanding the molecular mechanisms through which VEC triggers the expression of a set of genes involved in endothelial differentiation and vascular stabilization. Methods and Results: We compared a VEC-null cell line with the same line reconstituted with VEC wild-type cDNA. VEC expression and clustering upregulated endothelial-specific genes with key roles in vascular stabilization including claudin-5, vascular endothelial-protein tyrosine phosphatase (VE-PTP), and von Willebrand factor (vWf). Mechanistically, VEC exerts this effect by inhibiting polycomb protein activity on the specific gene promoters. This is achieved by preventing nuclear translocation of FoxO1 (Forkhead box protein O1) and β-catenin, which contribute to PRC2 (polycomb repressive complex-2) binding to promoter regions of claudin-5, VE-PTP, and vWf. VEC/β-catenin complex also sequesters a core subunit of PRC2 (Ezh2 [enhancer of zeste homolog 2]) at the cell membrane, preventing its nuclear translocation. Inhibition of Ezh2/VEC association increases Ezh2 recruitment to claudin-5, VE-PTP, and vWf promoters, causing gene downregulation. RNA sequencing comparison of VEC-null and VEC-positive cells suggested a more general role of VEC in activating endothelial genes and triggering a vascular stability-related gene expression program. In pathological angiogenesis of human ovarian carcinomas, reduced VEC expression paralleled decreased levels of claudin-5 and VE-PTP. Conclusions: These data extend the knowledge of polycomb-mediated regulation of gene expression to endothelial cell differentiation and vessel maturation. The identified mechanism opens novel therapeutic opportunities to modulate endothelial gene expression and induce vascular normalization through pharmacological inhibition of the polycomb-mediated repression system. PMID:29233846

VE-Cadherin-Mediated Epigenetic Regulation of Endothelial Gene Expression.

PubMed

Morini, Marco F; Giampietro, Costanza; Corada, Monica; Pisati, Federica; Lavarone, Elisa; Cunha, Sara I; Conze, Lei L; O'Reilly, Nicola; Joshi, Dhira; Kjaer, Svend; George, Roger; Nye, Emma; Ma, Anqi; Jin, Jian; Mitter, Richard; Lupia, Michela; Cavallaro, Ugo; Pasini, Diego; Calado, Dinis P; Dejana, Elisabetta; Taddei, Andrea

2018-01-19

The mechanistic foundation of vascular maturation is still largely unknown. Several human pathologies are characterized by deregulated angiogenesis and unstable blood vessels. Solid tumors, for instance, get their nourishment from newly formed structurally abnormal vessels which present wide and irregular interendothelial junctions. Expression and clustering of the main endothelial-specific adherens junction protein, VEC (vascular endothelial cadherin), upregulate genes with key roles in endothelial differentiation and stability. We aim at understanding the molecular mechanisms through which VEC triggers the expression of a set of genes involved in endothelial differentiation and vascular stabilization. We compared a VEC-null cell line with the same line reconstituted with VEC wild-type cDNA. VEC expression and clustering upregulated endothelial-specific genes with key roles in vascular stabilization including claudin-5 , vascular endothelial-protein tyrosine phosphatase ( VE-PTP ), and von Willebrand factor ( vWf ). Mechanistically, VEC exerts this effect by inhibiting polycomb protein activity on the specific gene promoters. This is achieved by preventing nuclear translocation of FoxO1 (Forkhead box protein O1) and β-catenin, which contribute to PRC2 (polycomb repressive complex-2) binding to promoter regions of claudin-5 , VE-PTP , and vWf . VEC/β-catenin complex also sequesters a core subunit of PRC2 (Ezh2 [enhancer of zeste homolog 2]) at the cell membrane, preventing its nuclear translocation. Inhibition of Ezh2/VEC association increases Ezh2 recruitment to claudin-5 , VE-PTP , and vWf promoters, causing gene downregulation. RNA sequencing comparison of VEC-null and VEC-positive cells suggested a more general role of VEC in activating endothelial genes and triggering a vascular stability-related gene expression program. In pathological angiogenesis of human ovarian carcinomas, reduced VEC expression paralleled decreased levels of claudin-5 and VE-PTP. These data extend the knowledge of polycomb-mediated regulation of gene expression to endothelial cell differentiation and vessel maturation. The identified mechanism opens novel therapeutic opportunities to modulate endothelial gene expression and induce vascular normalization through pharmacological inhibition of the polycomb-mediated repression system. © 2017 The Authors.

Talimogene Laherparepvec for Treating Metastatic Melanoma: An Evidence Review Group Perspective of a NICE Single Technology Appraisal.

PubMed

Fleeman, Nigel; Bagust, Adrian; Boland, Angela; Beale, Sophie; Richardson, Marty; Krishan, Ashma; Stainthorpe, Angela; Abdulla, Ahmed; Kotas, Eleanor; Banks, Lindsay; Payne, Miranda

2017-10-01

The National Institute for Health and Care Excellence (NICE) invited the manufacturer (Amgen) of talimogene laherparepvec (T-VEC) to submit clinical and cost-effectiveness evidence for previously untreated advanced (unresectable or metastatic) melanoma as part of the Institute's Single Technology Appraisal process. The Liverpool Reviews and Implementation Group (LRiG) at the University of Liverpool was commissioned to act as the Evidence Review Group (ERG). This article presents a summary of the company's submission of T-VEC, the ERG review and the resulting NICE guidance (TA410), issued in September 2016. T-VEC is an oncolytic virus therapy granted a marketing authorisation by the European Commission for the treatment of adults with unresectable melanoma that is regionally or distantly metastatic (stage IIIB, IIIC and IVM1a) with no bone, brain, lung or other visceral disease. Clinical evidence for T-VEC versus granulocyte-macrophage colony-stimulating factor (GM-CSF) was derived from the multinational, open-label randomised controlled OPTiM trial [Oncovex (GM-CSF) Pivotal Trial in Melanoma]. In accordance with T-VEC's marketing authorisation, the company's submission focused primarily on 249 patients with stage IIIB to stage IV/M1a disease who constituted 57% of the overall trial population (T-VEC, n = 163 and GM-CSF, n = 86). Results from analyses of durable response rate, objective response rate, time to treatment failure and overall survival all showed marked and statistically significant improvements for patients treated with T-VEC compared with those treated with GM-CSF. However, GM-CSF is not used to treat melanoma in clinical practice. It was not possible to compare treatment with T-VEC with an appropriate comparator using conventionally accepted methods due to the absence of comparative head-to-head data or trials with sufficient common comparators. Therefore, the company compared T-VEC with ipilimumab using what it described as modified Korn and two-step Korn methods. Results from these analyses suggested that treatment with T-VEC was at least as effective as treatment with ipilimumab. Using the discounted patient access scheme (PAS) price for T-VEC and list price for ipilimumab, the company reported incremental cost-effectiveness ratios (ICERs) per quality-adjusted life-year (QALY) gained. For the comparison of treatment with T-VEC versus ipilimumab, the ICER per QALY gained was -£16,367 using the modified Korn method and -£60,271 using the two-step Korn method. The NICE Appraisal Committee (AC) agreed with the ERG that the company's methods for estimating clinical effectiveness of T-VEC versus ipilimumab were flawed and therefore produced unreliable results for modelling progression in stage IIIB to stage IVM1a melanoma. The AC concluded that the clinical and cost effectiveness of treatment with T-VEC compared with ipilimumab is unknown in patients with stage IIIB to stage IV/M1a disease. However, the AC considered that T-VEC may be a reasonable option for treating patients who are unsuitable for treatment with systemically administered immunotherapies (such as ipilimumab). T-VEC was therefore recommended by NICE as a treatment option for adults with unresectable, regionally or distantly metastatic (stage IIIB to stage IVM1a) melanoma that has not spread to bone, brain, lung or other internal organs, only if treatment with systemically administered immunotherapies is not suitable and the company provides T-VEC at the agreed discounted PAS price.

Pharmacokinetic drug evaluation of talimogene laherparepvec for the treatment of advanced melanoma.

PubMed

Burke, Erin E; Zager, Jonathan S

2018-04-01

Current treatment of advanced melanoma is rapidly changing with the introduction of new and effective therapies including systemic as well as locoregional therapies. An example of one such locoregional therapy is intralesional injection with talimogene laherparepvec (T-VEC). Areas covered: T-VEC has been shown in a number of studies to be an effective treatment for patients with stage IIIB, IIIC and IVM1a melanoma. In this article the effectiveness, pharmacokinetics and safety profile of T-VEC is reviewed. Additionally, new research looking at combinations of T-VEC and systemic immunotherapies is reviewed. Expert opinion: Overall, T-VEC is an easily administered, safe, well tolerated and effective oncolytic viral therapy for the treatment of stage IIIB, IIIC, IVM1a unresectable and injectable metastatic melanoma. Recently published studies are showing promising results when T-VEC is combined with systemic therapy and this may be the way of the not too distant future in how we treat metastatic melanoma. Continued work regarding the use of T-VEC with other systemic agents will provide new and more effective treatment strategies for advanced melanoma.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Santini, Danilo J.; Poyer, David A.

Vector error correction (VEC) was used to test the importance of a theoretical causal chain from transportation fuel cost to vehicle sales to macroeconomic activity. Real transportation fuel cost was broken into two cost components: real gasoline price (rpgas) and real personal consumption of gasoline and other goods (gas). Real personal consumption expenditure on vehicles (RMVE) represented vehicle sales. Real gross domestic product (rGDP) was used as the measure of macroeconomic activity. The VEC estimates used quarterly data from the third quarter of 1952 to the first quarter of 2014. Controlling for the financial causes of the recent Great Recession,more » real homeowners’ equity (equity) and real credit market instruments liability (real consumer debt, rcmdebt) were included. Results supported the primary hypothesis of the research, but also introduced evidence that another financial path through equity is important, and that use of the existing fleet of vehicles (not just sales of vehicles) is an important transport-related contributor to macroeconomic activity. Consumer debt reduction is estimated to be a powerful short-run force reducing vehicle sales. Findings are interpreted in the context of the recent Greene, Lee, and Hopson (2012) (hereafter GLH) estimation of the magnitude of three distinct macroeconomic damage effects that result from dependence on imported oil, the price of which is manipulated by the Organization of Petroleum Exporting Countries (OPEC). The three negative macroeconomic impacts are due to (1) dislocation (positive oil price shock), (2) high oil price levels, and (3) a high value of the quantity of oil imports times an oil price delta (cartel price less competitive price). The third of these is the wealth effect. The VEC model addresses the first two, but the software output from the model (impulse response plots) does not isolate them. Nearly all prior statistical tests in the literature have used vector autoregression (VAR) and autoregressive distributed lag models that considered effects of oil price changes, but did not account for effects of oil price levels. Gasoline prices were rarely examined. The tests conducted in this report evaluate gasoline instead of oil.« less

Learning atoms for materials discovery.

PubMed

Zhou, Quan; Tang, Peizhe; Liu, Shenxiu; Pan, Jinbo; Yan, Qimin; Zhang, Shou-Cheng

2018-06-26

Exciting advances have been made in artificial intelligence (AI) during recent decades. Among them, applications of machine learning (ML) and deep learning techniques brought human-competitive performances in various tasks of fields, including image recognition, speech recognition, and natural language understanding. Even in Go, the ancient game of profound complexity, the AI player has already beat human world champions convincingly with and without learning from the human. In this work, we show that our unsupervised machines (Atom2Vec) can learn the basic properties of atoms by themselves from the extensive database of known compounds and materials. These learned properties are represented in terms of high-dimensional vectors, and clustering of atoms in vector space classifies them into meaningful groups consistent with human knowledge. We use the atom vectors as basic input units for neural networks and other ML models designed and trained to predict materials properties, which demonstrate significant accuracy. Copyright © 2018 the Author(s). Published by PNAS.

Comparisons and Selections of Features and Classifiers for Short Text Classification

NASA Astrophysics Data System (ADS)

Wang, Ye; Zhou, Zhi; Jin, Shan; Liu, Debin; Lu, Mi

2017-10-01

Short text is considerably different from traditional long text documents due to its shortness and conciseness, which somehow hinders the applications of conventional machine learning and data mining algorithms in short text classification. According to traditional artificial intelligence methods, we divide short text classification into three steps, namely preprocessing, feature selection and classifier comparison. In this paper, we have illustrated step-by-step how we approach our goals. Specifically, in feature selection, we compared the performance and robustness of the four methods of one-hot encoding, tf-idf weighting, word2vec and paragraph2vec, and in the classification part, we deliberately chose and compared Naive Bayes, Logistic Regression, Support Vector Machine, K-nearest Neighbor and Decision Tree as our classifiers. Then, we compared and analysed the classifiers horizontally with each other and vertically with feature selections. Regarding the datasets, we crawled more than 400,000 short text files from Shanghai and Shenzhen Stock Exchanges and manually labeled them into two classes, the big and the small. There are eight labels in the big class, and 59 labels in the small class.

Dynamics relationship between stock prices and economic variables in Malaysia

NASA Astrophysics Data System (ADS)

Chun, Ooi Po; Arsad, Zainudin; Huen, Tan Bee

2014-07-01

Knowledge on linkages between stock prices and macroeconomic variables are essential in the formulation of effective monetary policy. This study investigates the relationship between stock prices in Malaysia (KLCI) with four selected macroeconomic variables, namely industrial production index (IPI), quasi money supply (MS2), real exchange rate (REXR) and 3-month Treasury bill (TRB). The variables used in this study are monthly data from 1996 to 2012. Vector error correction (VEC) model and Kalman filter (KF) technique are utilized to assess the impact of macroeconomic variables on the stock prices. The results from the cointegration test revealed that the stock prices and macroeconomic variables are cointegrated. Different from the constant estimate from the static VEC model, the KF estimates noticeably exhibit time-varying attributes over the entire sample period. The varying estimates of the impact coefficients should be better reflect the changing economic environment. Surprisingly, IPI is negatively related to the KLCI with the estimates of the impact slowly increase and become positive in recent years. TRB is found to be generally negatively related to the KLCI with the impact fluctuating along the constant estimate of the VEC model. The KF estimates for REXR and MS2 show a mixture of positive and negative impact on the KLCI. The coefficients of error correction term (ECT) are negative in majority of the sample period, signifying the stock prices responded to stabilize any short term deviation in the economic system. The findings from the KF model indicate that any implication that is based on the usual static model may lead to authorities implementing less appropriate policies.

Alloying and Properties of C14–NbCr2 and A15–Nb3X (X = Al, Ge, Si, Sn) in Nb–Silicide-Based Alloys

PubMed Central

Tsakiropoulos, Panos

2018-01-01

The oxidation of Nb–silicide-based alloys is improved with Al, Cr, Ge or Sn addition(s). Depending on addition(s) and its(their) concentration(s), alloyed C14-AB2 Laves and A15-A3X phases can be stable in the microstructures of the alloys. In both phases, A is the transition metal(s), and B and X respectively can be Cr, Al, Ge, Si or Sn, and Al, Ge, Si or Sn. The alloying, creep and hardness of these phases were studied using the composition weighted differences in electronegativity (∆χ), average valence electron concentrations (VEC) and atomic sizes. For the Laves phase (i) the VEC and ∆χ were in the ranges 4.976 < VEC < 5.358 and −0.503 < ∆χ < −0.107; (ii) the concentration of B (=Al + Cr + Ge + Si + Sn) varied from 50.9 to 64.5 at %; and (iii) the Cr concentration was in the range of 35.8 < Cr < 51.6 at %. Maps of ∆χ versus Cr, ∆χ versus VEC, and VEC versus atomic size separated the alloying behaviours of the elements. Compared with unalloyed NbCr2, the VEC decreased and ∆χ increased in Nb(Cr,Si)2, and the changes in both parameters increased when Nb was substituted by Ti, and Cr by Si and Al, or Si and Ge, or Si and Sn. For the A15 phase (i) the VEC and ∆χ were in the ranges 4.38 < VEC < 4.89 and 0.857 < ∆χ < 1.04, with no VEC values between 4.63 and 4.72 and (ii) the concentration of X (=Al + Ge + Si + Sn) varied from 16.3 to 22.7 at %. The VEC versus ∆χ map separated the alloying behaviours of elements. The hardness of A15-Nb3X was correlated with the parameters ∆χ and VEC. The hardness increased with increases in ∆χ and VEC. Compared with Nb3Sn, the ∆χ and hardness of Nb3(Si,Sn) increased. The substitution of Nb by Cr had the same effect on ∆χ and hardness as Hf or Ti. The ∆χ and hardness increased with Ti concentration. The addition of Al in Nb3(Si,Sn,Al) decreased the ∆χ and increased the hardness. When Ti and Hf, or Ti, Hf and Cr, were simultaneously present with Al, the ∆χ was decreased and the hardness was unchanged. The better creep of Nb(Cr,Si)2 compared with the unalloyed Laves phase was related to the decrease in the VEC and ∆χ parameters. PMID:29518920

Alloying and Properties of C14-NbCr₂ and A15-Nb₃X (X = Al, Ge, Si, Sn) in Nb-Silicide-Based Alloys.

PubMed

Tsakiropoulos, Panos

2018-03-07

The oxidation of Nb-silicide-based alloys is improved with Al, Cr, Ge or Sn addition(s). Depending on addition(s) and its(their) concentration(s), alloyed C14-AB₂ Laves and A15-A₃X phases can be stable in the microstructures of the alloys. In both phases, A is the transition metal(s), and B and X respectively can be Cr, Al, Ge, Si or Sn, and Al, Ge, Si or Sn. The alloying, creep and hardness of these phases were studied using the composition weighted differences in electronegativity (∆χ), average valence electron concentrations (VEC) and atomic sizes. For the Laves phase (i) the VEC and ∆χ were in the ranges 4.976 < VEC < 5.358 and -0.503 < ∆χ < -0.107; (ii) the concentration of B (=Al + Cr + Ge + Si + Sn) varied from 50.9 to 64.5 at %; and (iii) the Cr concentration was in the range of 35.8 < Cr < 51.6 at %. Maps of ∆χ versus Cr, ∆χ versus VEC, and VEC versus atomic size separated the alloying behaviours of the elements. Compared with unalloyed NbCr₂, the VEC decreased and ∆χ increased in Nb(Cr,Si)₂, and the changes in both parameters increased when Nb was substituted by Ti, and Cr by Si and Al, or Si and Ge, or Si and Sn. For the A15 phase (i) the VEC and ∆χ were in the ranges 4.38 < VEC < 4.89 and 0.857 < ∆χ < 1.04, with no VEC values between 4.63 and 4.72 and (ii) the concentration of X (=Al + Ge + Si + Sn) varied from 16.3 to 22.7 at %. The VEC versus ∆χ map separated the alloying behaviours of elements. The hardness of A15-Nb₃X was correlated with the parameters ∆χ and VEC. The hardness increased with increases in ∆χ and VEC. Compared with Nb₃Sn, the ∆χ and hardness of Nb₃(Si,Sn) increased. The substitution of Nb by Cr had the same effect on ∆χ and hardness as Hf or Ti. The ∆χ and hardness increased with Ti concentration. The addition of Al in Nb₃(Si,Sn,Al) decreased the ∆χ and increased the hardness. When Ti and Hf, or Ti, Hf and Cr, were simultaneously present with Al, the ∆χ was decreased and the hardness was unchanged. The better creep of Nb(Cr,Si)₂ compared with the unalloyed Laves phase was related to the decrease in the VEC and ∆χ parameters.

The large-scale gravitational bias from the quasi-linear regime.

NASA Astrophysics Data System (ADS)

Bernardeau, F.

1996-08-01

It is known that in gravitational instability scenarios the nonlinear dynamics induces non-Gaussian features in cosmological density fields that can be investigated with perturbation theory. Here, I derive the expression of the joint moments of cosmological density fields taken at two different locations. The results are valid when the density fields are filtered with a top-hat filter window function, and when the distance between the two cells is large compared to the smoothing length. In particular I show that it is possible to get the generating function of the coefficients C_p,q_ defined by <δ^p^({vec}(x)_1_)δ^q^({vec}(x)_2_)>_c_=C_p,q_ <δ^2^({vec}(x))>^p+q-2^ <δ({vec}(x)_1_)δ({vec}(x)_2_)> where δ({vec}(x)) is the local smoothed density field. It is then possible to reconstruct the joint density probability distribution function (PDF), generalizing for two points what has been obtained previously for the one-point density PDF. I discuss the validity of the large separation approximation in an explicit numerical Monte Carlo integration of the C_2,1_ parameter as a function of |{vec}(x)_1_-{vec}(x)_2_|. A straightforward application is the calculation of the large-scale ``bias'' properties of the over-dense (or under-dense) regions. The properties and the shape of the bias function are presented in details and successfully compared with numerical results obtained in an N-body simulation with CDM initial conditions.

Identification of Sources with Unknown Wavefronts.

DTIC Science & Technology

1988-03-31

as p p [zi~ -it (1.28)ti Thle scalar (l-) is precisel thle " projection " of V oil tilie iiiit vec(tor of lie pt h axis. So (.1.28) simiply means thle t...Arbitrarily forget about t,’ and 0 by deciding I:’ 0 anud assiuuule I ie two So urce vectoIrs are oithog iial (very large arra s) a rather cruile...be thle mlodel. Reiterating a remark already Iii a de a 1 i t lie colit inlis p~ lanle waves andL large parametric dlescri ptimons, Lii’ phsca meaning

Paeonol protects rat vascular endothelial cells from ox-LDL-induced injury in vitro via downregulating microRNA-21 expression and TNF-α release

PubMed Central

Liu, Ya-rong; Chen, Jun-jun; Dai, Min

2014-01-01

Aim: Paeonol (2′-hydroxy-4′-methoxyacetophenone) from Cortex moutan root is a potential therapeutic agent for atherosclerosis. This study sought to investigate the mechanisms underlying anti-inflammatory effects of paeonol in rat vascular endothelial cells (VECs) in vitro. Methods: VECs were isolated from rat thoracic aortas. The cells were pretreated with paeonol for 24 h, and then stimulated with ox-LDL for another 24 h. The expression of microRNA-21 (miR-21) and PTEN in VECs was analyzed using qRT-PCR. The expression of PTEN protein was detected by Western blotting. TNF-α release by VECs was measured by ELISA. Results: Ox-LDL treatment inhibited VEC growth in dose- and time-dependent manners (the value of IC50 was about 20 mg/L at 24 h). Furthermore, ox-LDL (20 mg/L) significantly increased miR-21 expression and inhibited the expression of PTEN, one of downstream target genes of miR-21 in VECs. In addition, ox-LDL (20 mg/L) significantly increased the release of TNF-α from VECs. Pretreatment with paeonol increased the survival rate of ox-LDL-treated VECs in dose- and time-dependent manners. Moreover, paeonol (120 μmol/L) prevented ox-LDL-induced increases in miR-21 expression and TNF-α release, and ox-LDL-induced inhibition in PTEN expression. A dual-luciferase reporter assay showed that miR-21 bound directly to PTEN's 3′-UTR, thus inhibiting PTEN expression. In ox-LDL treated VECs, transfection with a miR-21 mimic significantly increased miR-21 expression and inhibited PTEN expression, and attenuated the protective effects of paeonol pretreatment, whereas transfection with an miR-21 inhibitor significantly decreased miR-21 expression and increased PTEN expression, thus enhanced the protective effects of paeonol pretreatment. Conclusion: miR-21 is an important target of paeonol for its protective effects against ox-LDL-induced VEC injury, which may play critical roles in development of atherosclerosis. PMID:24562307

Neuronal Effects of Sugammadex in combination with Rocuronium or Vecuronium

PubMed Central

Aldasoro, Martin; Jorda, Adrian; Aldasoro, Constanza; Marchio, Patricia; Guerra-Ojeda, Sol; Gimeno-Raga, Marc; Mauricio, Mª Dolores; Iradi, Antonio; Obrador, Elena; Vila, Jose Mª; Valles, Soraya L.

2017-01-01

Rocuronium (ROC) and Vecuronium (VEC) are the most currently used steroidal non-depolarizing neuromuscular blocking (MNB) agents. Sugammadex (SUG) rapidly reverses steroidal NMB agents after anaesthesia. The present study was conducted in order to evaluate neuronal effects of SUG alone and in combination with both ROC and VEC. Using MTT, CASP-3 activity and Western-blot we determined the toxicity of SUG, ROC or VEC in neurons in primary culture. SUG induces apoptosis/necrosis in neurons in primary culture and increases cytochrome C (CytC), apoptosis-inducing factor (AIF), Smac/Diablo and Caspase 3 (CASP-3) protein expression. Our results also demonstrated that both ROC and VEC prevent these SUG effects. The protective role of both ROC and VEC could be explained by the fact that SUG encapsulates NMB drugs. In BBB impaired conditions it would be desirable to control SUG doses to prevent the excess of free SUG in plasma that may induce neuronal damage. A balance between SUG, ROC or VEC would be necessary to prevent the risk of cell damage. PMID:28367082

Nonuniform continuum model for solvatochromism based on frozen-density embedding theory.

PubMed

Shedge, Sapana Vitthal; Wesolowski, Tomasz A

2014-10-20

Frozen-density embedding theory (FDET) provides the formal framework for multilevel numerical simulations, such that a selected subsystem is described at the quantum mechanical level, whereas its environment is described by means of the electron density (frozen density; ${\\rho _{\\rm{B}} (\\vec r)}$). The frozen density ${\\rho _{\\rm{B}} (\\vec r)}$ is usually obtained from some lower-level quantum mechanical methods applied to the environment, but FDET is not limited to such choices for ${\\rho _{\\rm{B}} (\\vec r)}$. The present work concerns the application of FDET, in which ${\\rho _{\\rm{B}} (\\vec r)}$ is the statistically averaged electron density of the solvent ${\\left\\langle {\\rho _{\\rm{B}} (\\vec r)} \\right\\rangle }$. The specific solute-solvent interactions are represented in a statistical manner in ${\\left\\langle {\\rho _{\\rm{B}} (\\vec r)} \\right\\rangle }$. A full self-consistent treatment of solvated chromophore, thus involves a single geometry of the chromophore in a given state and the corresponding ${\\left\\langle {\\rho _{\\rm{B}} (\\vec r)} \\right\\rangle }$. We show that the coupling between the two descriptors might be made in an approximate manner that is applicable for both absorption and emission. The proposed protocol leads to accurate (error in the range of 0.05 eV) descriptions of the solvatochromic shifts in both absorption and emission. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Relation extraction for biological pathway construction using node2vec.

PubMed

Kim, Munui; Baek, Seung Han; Song, Min

2018-06-13

Systems biology is an important field for understanding whole biological mechanisms composed of interactions between biological components. One approach for understanding complex and diverse mechanisms is to analyze biological pathways. However, because these pathways consist of important interactions and information on these interactions is disseminated in a large number of biomedical reports, text-mining techniques are essential for extracting these relationships automatically. In this study, we applied node2vec, an algorithmic framework for feature learning in networks, for relationship extraction. To this end, we extracted genes from paper abstracts using pkde4j, a text-mining tool for detecting entities and relationships. Using the extracted genes, a co-occurrence network was constructed and node2vec was used with the network to generate a latent representation. To demonstrate the efficacy of node2vec in extracting relationships between genes, performance was evaluated for gene-gene interactions involved in a type 2 diabetes pathway. Moreover, we compared the results of node2vec to those of baseline methods such as co-occurrence and DeepWalk. Node2vec outperformed existing methods in detecting relationships in the type 2 diabetes pathway, demonstrating that this method is appropriate for capturing the relatedness between pairs of biological entities involved in biological pathways. The results demonstrated that node2vec is useful for automatic pathway construction.

New structure of high-pressure body-centered orthorhombic Fe 2SiO 4

DOE PAGES

Yamanaka, Takamitsu; Kyono, Atsushi; Nakamoto, Yuki; ...

2015-08-01

Here, a structural change in Fe 2SiO 4 spinel and the structure of a new high pressure phase are determined by Rietveld 26 profile fitting of x-ray diffraction data up to 64 GPa at ambient temperature. The compression curve of the spinel is discontinuous at approximately 20 GPa. Fe Kβ x-ray emission measurements at high pressure show that the transition from a high spin (HS) to an intermediate spin (IS) state begins at 17 GPa in the spinel phase. The IS electronic state is gradually enhanced with pressure, which results in an isostructural phase transition. A transition from the cubic spinel structure to a body centered orthorhombic phase (I-Fe 2SiO 4) with space group Imma and Z=4 was observed at approximately 34 GPa. The structure of I-Fe 2SiO 4 has two crystallographically distinct FeO 6 octahedra, which are arranged in layers parallel to (101) and (011) and are very similar to the layers of FeO 6 octahedra that constitute the spinel structure. Silicon also exists in six-fold coordination in I-Fe 2SiO 4. The transformation to the new high-pressure phase is reversible under decompression at ambient temperature. A Martensitic transformation of each slab of the spinel structure with translation vector [more » $$\\vec{1/8}$$ $$\\vec{1/8}$$ $$\\vec{1/8}$$] generates the I-Fe 2SiO 4 structure. Laser heating of I-Fe 2SiO 4 at 1500 K results in a decomposition of the material to rhombohedral FeO and SiO 2 stishovite.« less

Safe and effective administration of T-VEC in a patient with heart transplantation and recurrent locally advanced melanoma.

PubMed

Schvartsman, Gustavo; Perez, Kristen; Flynn, Jill E; Myers, Jeffrey N; Tawbi, Hussein

2017-01-01

Immunotherapy plays a key role in the treatment of metastatic melanoma. Patients with autoimmune conditions and/or on immunosuppressive therapy due to orthotropic transplants, however, are systematically excluded from clinical trials. Talimogene laherparepvec (T-VEC) is the first oncolytic virus to be approved by the FDA for cancer therapy. To our knowledge, this is the first report of T-VEC being administered in the setting of an organ transplant recipient. Here we present the case of a patient with recurrent locally advanced cutaneous melanoma receiving salvage T-VEC therapy in the setting of orthotropic heart transplantation. After 5 cycles of therapy, no evidence of graft rejection has been observed to date, and the patient achieved a complete remission, and is currently off therapy. This case advocates for further investigation on the safety and efficacy of immunotherapeutic approaches, such as T-VEC, in solid organ transplant recipients.

Mapping higher-order relations between brain structure and function with embedded vector representations of connectomes.

PubMed

Rosenthal, Gideon; Váša, František; Griffa, Alessandra; Hagmann, Patric; Amico, Enrico; Goñi, Joaquín; Avidan, Galia; Sporns, Olaf

2018-06-05

Connectomics generates comprehensive maps of brain networks, represented as nodes and their pairwise connections. The functional roles of nodes are defined by their direct and indirect connectivity with the rest of the network. However, the network context is not directly accessible at the level of individual nodes. Similar problems in language processing have been addressed with algorithms such as word2vec that create embeddings of words and their relations in a meaningful low-dimensional vector space. Here we apply this approach to create embedded vector representations of brain networks or connectome embeddings (CE). CE can characterize correspondence relations among brain regions, and can be used to infer links that are lacking from the original structural diffusion imaging, e.g., inter-hemispheric homotopic connections. Moreover, we construct predictive deep models of functional and structural connectivity, and simulate network-wide lesion effects using the face processing system as our application domain. We suggest that CE offers a novel approach to revealing relations between connectome structure and function.

BioVEC: a program for biomolecule visualization with ellipsoidal coarse-graining.

PubMed

Abrahamsson, Erik; Plotkin, Steven S

2009-09-01

Biomolecule Visualization with Ellipsoidal Coarse-graining (BioVEC) is a tool for visualizing molecular dynamics simulation data while allowing coarse-grained residues to be rendered as ellipsoids. BioVEC reads in configuration files, which may be output from molecular dynamics simulations that include orientation output in either quaternion or ANISOU format, and can render frames of the trajectory in several common image formats for subsequent concatenation into a movie file. The BioVEC program is written in C++, uses the OpenGL API for rendering, and is open source. It is lightweight, allows for user-defined settings for and texture, and runs on either Windows or Linux platforms.

Circulating fibrocytes stabilize blood vessels during angiogenesis in a paracrine manner.

PubMed

Li, Jinqing; Tan, Hong; Wang, Xiaolin; Li, Yuejun; Samuelson, Lisa; Li, Xueyong; Cui, Caibin; Gerber, David A

2014-02-01

Accumulating evidence supports that circulating fibrocytes play important roles in angiogenesis. However, the specific role of fibrocytes in angiogenesis and the underlying mechanisms remain unclear. In this study, we found that fibrocytes stabilized newly formed blood vessels in a mouse wound-healing model by inhibiting angiogenesis during the proliferative phase and inhibiting blood vessel regression during the remodeling phase. Fibrocytes also inhibited angiogenesis in a Matrigel mouse model. In vitro study showed that fibrocytes inhibited both the apoptosis and proliferation of vascular endothelial cells (VECs) in a permeable support (Transwell) co-culture system. In a three-dimensional collagen gel, fibrocytes stabilized the VEC tubes by decreasing VEC tube density on stimulation with growth factors and preventing VEC tube regression on withdrawal of growth factors. Further mechanistic investigation revealed that fibrocytes expressed many prosurvival factors that are responsible for the prosurvival effect of fibrocytes on VECs and blood vessels. Fibrocytes also expressed angiogenesis inhibitors, including thrombospondin-1 (THBS1). THBS1 knockdown partially blocked the fibrocyte-induced inhibition of VEC proliferation in the Transwell co-culture system and recovered the fibrocyte-induced decrease of VEC tube density in collagen gel. Purified fibrocytes transfected with THBS1 siRNA partially recovered the fibrocyte-induced inhibition of angiogenesis in both the wound-healing and Matrigel models. In conclusion, our findings reveal that fibrocytes stabilize blood vessels via prosurvival factors and anti-angiogenic factors, including THBS1. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Vanadium-Enriched Cordyceps sinensis, a Contemporary Treatment Approach to Both Diabetes and Depression in Rats

PubMed Central

Guo, Jianyou; Li, ChangYu; Wang, Jie; Liu, Yongmei; Zhang, Jiahui

2011-01-01

This article studies a contemporary treatment approach toward both diabetes and depression management by vanadium-enriched Cordyceps sinensis (VECS). Streptozotocin-induced hyperglycemic rats were used in the study. After the rats were administered with VECS, a significant reduction in blood glucose levels was seen (P < .05) and the levels of serum insulin increased significantly (P < .05). At the same time, the study revealed a significant decrease in immobility with a corresponding increase in the swimming and climbing behavior in hyperglycemic rats following VECS treatment. The results described herein demonstrate that VECS is a contemporary treatment approach that advocates an aggressive stance toward both diabetes and depression management. PMID:21799679

An inventory on rotational kinematics of a particle: unravelling misconceptions and pitfalls in reasoning

NASA Astrophysics Data System (ADS)

Mashood, K. K.; Singh, Vijay A.

2012-09-01

Student difficulties regarding the angular velocity (\\vec{\\omega }) and angular acceleration (\\vec{\\alpha }) of a particle have remained relatively unexplored in contrast to their linear counterparts. We present an inventory comprising multiple choice questions aimed at probing misconceptions and eliciting ill-suited reasoning patterns. The development of the inventory was based on interactions with students, teachers and experts. We report misconceptions, some of which are parallel to those found earlier in linear kinematics. Fixations with inappropriate prototypes were uncovered. Many students and even teachers mistakenly assume that all rotational motion is necessarily circular. A persistent notion that the direction of \\vec{\\omega } and \\vec{\\alpha } should be ‘along’ the motion exists. Instances of indiscriminate usage of equations were identified.

Bone marrow mesenchymal stem cells could acquire the phenotypes of epithelial cells and accelerate vaginal reconstruction combined with small intestinal submucosa.

PubMed

Li, Yanan; Liu, Fangfang; Zhang, Zhiqiang; Zhang, Mingle; Cao, Shanjin; Li, Yachai; Zhang, Lin; Huang, Xianghua; Xu, Yanfang

2015-11-01

Grafting material for vaginal reconstruction commonly includes the bowel, peritoneum, skin, and amniotic membrane. Bone marrow mesenchymal stem cells (MSCs) have the potential of multilineage differentiation into a variety of cells and have been widely explored in tissue engineering. In the current study, we examined whether MSCs could be differentiated to vaginal epithelial cells (VECs) upon co-culturing with VECs. We also examined whether Wnt/β-catenin signaling pathway is implicated in such differentiation. Co-culture of MSCs with VECs using a transwell insert system (with no direct contact) induced the expression of VECs marker AE1/AE3 in MSCs. MSCs combined with small intestinal submucosa (SIS) scaffold were implanted in place of the native vagina in rats to observe the implications for vaginal reconstruction in vivo. Anatomic repair of neovagina was assessed by histological staining for H/E and Masson's Trichrome. GSK-3β and β-catenin, main members of Wnt/β-catenin signaling pathway, in MSCs were increased upon co-culturing with VECs. Exposure of co-cultured MSCs to a Wnt/β-catenin signaling activator, lithium chloride (LiCl, 20 µM) increased phosphorylated GSK-3β and β-catenin and enhanced expression of AE1/AE3. In vivo-grafted cells displayed significant matrix infiltration and expressed epithelial markers in neovagina. These findings suggest that MSCs could acquire the phenotype of VECs when co-cultured with VECs, possibly via activation of Wnt/β-catenin signaling. MSCs provide an alternative cell source for potential use in vaginal tissue engineering. © 2015 International Federation for Cell Biology.

Role of endothelin-1 and its receptors, ETA and ETB, in the survival of human vascular endothelial cells.

PubMed

Mikhail, Marianne; Vachon, Pierre H; D'Orléans-Juste, Pedro; Jacques, Danielle; Bkaily, Ghassan

2017-10-01

Our previous work showed the presence of endothelin-1 (ET-1) receptors, ET A and ET B , in human vascular endothelial cells (hVECs). In this study, we wanted to verify whether ET-1 plays a role in the survival of hVECs via the activation of its receptors ET A and (or) ET B (ET A R and ET B R, respectively). Our results showed that treatment of hVECs with ET-1 prevented apoptosis induced by genistein, an effect that was mimicked by treatment with ET B R-specific agonist IRL1620. Furthermore, blockade of ET B R with the selective ET B R antagonist A-192621 prevented the anti-apoptotic effect of ET-1 in hVECs. However, activation of ET A receptor alone did not seem to contribute to the anti-apoptotic effect of ET-1. In addition, the anti-apoptotic effect of ET B R was found to be associated with caspase 3 inhibition and does not depend on the density of this type of receptor. In conclusion, our results showed that ET-1 possesses an anti-apoptotic effect in hVECs and that this effect is mediated, to a great extent, via the activation of ET B R. This study revealed a new role for ET B R in the survival of hVECs.

Treatment of catastrophic antiphospholipid syndrome with defibrotide, a proposed vascular endothelial cell modulator.

PubMed

Burcoglu-O'Ral, Arsinur; Erkan, Doruk; Asherson, Ronald

2002-09-01

To define at the molecular level the vascular endothelial cell (VEC) injury characteristics of catastrophic antiphospholipid syndrome (CAPS) and to report successful therapeutic use of a VEC modulator, defibrotide. We describe a 55-year-old man with primary APS with an intractable prothrombotic state (CAPS) resistant to combined therapy with heparin, warfarin, aspirin, and dipyridamole. Treatment with defibrotide was conducted in the context of an investigational phase II protocol where the dose was regulated and individualized by disease/patient-specific molecular and clinical markers. The patient entered complete remission with defibrotide treatment. During treatment, dose dependent pharmacological actions of defibrotide and key stress markers for VEC injury were identified. Evidence of defibrotide's polypharmacology included downregulation of cytokines, notably tumor necrosis factor-alpha, as the earliest effect, cellular differentiation of VEC, possibly with direct regulatory effect over cellular genes, and the reversal of platelet consumption and prothrombotic state. Von Willebrand antigen levels were used as the sole marker to guide therapy. This case demonstrates effective remission of CAPS with defibrotide treatment. In contrast to theories that CAPS is triggered by ischemic and thrombotic tissue damage, these data present VEC injury as the primary and representative lesion of CAPS. The pathogenesis may involve concurrent impairment of different VEC functions. Achieving remission may require a polypharmacologic approach, represented here by use of defibrotide.

Global phase diagram and quantum spin liquids in a spin- 1 2 triangular antiferromagnet

DOE PAGES

Gong, Shou-Shu; Zhu, Wei; Zhu, Jianxin; ...

2017-08-09

For this research, we study the spin-1/2 Heisenberg model on the triangular lattice with the nearest-neighbor J 1 > 0 , the next-nearest-neighobr J 2 > 0 Heisenberg interactions, and the additional scalar chiral interaction Jχ (more » $$\\vec{S}$$ i × $$\\vec{S}$$ j ) · $$\\vec{S}$$ k for the three spins in all the triangles using large-scale density matrix renormalization group calculation on cylinder geometry. With increasing J 2 (J 2 / J 1 ≤ 0.3 ) and Jχ (Jχ / J 1 ≤ 1.0 ) interactions, we establish a quantum phase diagram with the magnetically ordered 120°, stripe, and noncoplanar tetrahedral phase. In between these magnetic order phases, we find a chiral spin liquid (CSL) phase, which is identified as a ν = 1/2 bosonic fractional quantum Hall state with possible spontaneous rotational symmetry breaking. By switching on the chiral interaction, we find that the previously identified spin liquid in the J 1 - J 2 triangular model (0.08 ≲ J 2 / J 1 ≲ 0.15) shows a phase transition to the CSL phase at very small Jχ. We also compute the spin triplet gap in both spin liquid phases, and our finite-size results suggest a large gap in the odd topological sector but a small or vanishing gap in the even sector. Lastly, we discuss the implications of our results on the nature of the spin liquid phases.« less

Human vaginal epithelial cells augment autophagy marker genes in response to Candida albicans infection.

PubMed

Shroff, Ankit; Sequeira, Roicy; Reddy, Kudumula Venkata Rami

2017-04-01

Autophagy plays an important role in clearance of intracellular pathogens. However, no information is available on its involvement in vaginal infections such as vulvo-vaginal candidiasis (VVC). VVC is intimately associated with the immune status of the human vaginal epithelial cells (VECs). The objective of our study is to decipher if autophagy process is involved during Candida albicans infection of VECs. In this study, C. albicans infection system was established using human VEC line (VK2/E6E7). Infection-induced change in the expression of autophagy markers like LC3 and LAMP-1 were analyzed by RT-PCR, q-PCR, Western blot, immunofluorescence and transmission electron microscopy (TEM) studies were carried out to ascertain the localization of autophagosomes. Multiplex ELISA was carried out to determine the cytokine profiles. Analysis of LC3 and LAMP-1 expression at mRNA and protein levels at different time points revealed up-regulation of these markers 6 hours post C. albicans infection. LC3 and LAMP-1 puncti were observed in infected VECs after 12 hours. TEM studies showed C. albicans entrapped in autophagosomes. Cytokines-TNF-α and IL-1β were up-regulated in culture supernatants of VECs at 12 hours post-infection. The results suggest that C. albicans invasion led to the activation of autophagy as a host defense mechanism of VECs. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

3D electrostatic gyrokinetic electron and fully kinetic ion simulation of lower-hybrid drift instability of Harris current sheet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhenyu; Lin, Yu; Wang, Xueyi

The eigenmode stability properties of three-dimensional lower-hybrid-drift-instabilities (LHDI) in a Harris current sheet with a small but finite guide magnetic field have been systematically studied by employing the gyrokinetic electron and fully kinetic ion (GeFi) particle-in-cell (PIC) simulation model with a realistic ion-to-electron mass ratio m i/m e. In contrast to the fully kinetic PIC simulation scheme, the fast electron cyclotron motion and plasma oscillations are systematically removed in the GeFi model, and hence one can employ the realistic m i/m e. The GeFi simulations are benchmarked against and show excellent agreement with both the fully kinetic PIC simulation and the analytical eigenmode theory. Our studies indicate that, for small wavenumbers, ky, along the current direction, the most unstable eigenmodes are peaked at the location wheremore » $$\\vec{k}$$• $$\\vec{B}$$ =0, consistent with previous analytical and simulation studies. Here, $$\\vec{B}$$ is the equilibrium magnetic field and $$\\vec{k}$$ is the wavevector perpendicular to the nonuniformity direction. As ky increases, however, the most unstable eigenmodes are found to be peaked at $$\\vec{k}$$ •$$\\vec{B}$$ ≠0. Additionally, the simulation results indicate that varying m i/m e, the current sheet width, and the guide magnetic field can affect the stability of LHDI. Simulations with the varying mass ratio confirm the lower hybrid frequency and wave number scalings.« less

3D electrostatic gyrokinetic electron and fully kinetic ion simulation of lower-hybrid drift instability of Harris current sheet

DOE PAGES

Wang, Zhenyu; Lin, Yu; Wang, Xueyi; ...

2016-07-07

The eigenmode stability properties of three-dimensional lower-hybrid-drift-instabilities (LHDI) in a Harris current sheet with a small but finite guide magnetic field have been systematically studied by employing the gyrokinetic electron and fully kinetic ion (GeFi) particle-in-cell (PIC) simulation model with a realistic ion-to-electron mass ratio m i/m e. In contrast to the fully kinetic PIC simulation scheme, the fast electron cyclotron motion and plasma oscillations are systematically removed in the GeFi model, and hence one can employ the realistic m i/m e. The GeFi simulations are benchmarked against and show excellent agreement with both the fully kinetic PIC simulation and the analytical eigenmode theory. Our studies indicate that, for small wavenumbers, ky, along the current direction, the most unstable eigenmodes are peaked at the location wheremore » $$\\vec{k}$$• $$\\vec{B}$$ =0, consistent with previous analytical and simulation studies. Here, $$\\vec{B}$$ is the equilibrium magnetic field and $$\\vec{k}$$ is the wavevector perpendicular to the nonuniformity direction. As ky increases, however, the most unstable eigenmodes are found to be peaked at $$\\vec{k}$$ •$$\\vec{B}$$ ≠0. Additionally, the simulation results indicate that varying m i/m e, the current sheet width, and the guide magnetic field can affect the stability of LHDI. Simulations with the varying mass ratio confirm the lower hybrid frequency and wave number scalings.« less

Peptide-modified PELCL electrospun membranes for regulation of vascular endothelial cells.

PubMed

Zhou, Fang; Jia, Xiaoling; Yang, Yang; Yang, Qingmao; Gao, Chao; Zhao, Yunhui; Fan, Yubo; Yuan, Xiaoyan

2016-11-01

The efficiency of biomaterials used in small vascular repair depends greatly on their ability to interact with vascular endothelial cells (VECs). Rapid endothelialization of the vascular grafts is a promising way to prevent thrombosis and intimal hyperplasia. In this work, modification of electrospun membranes of poly(ethylene glycol)-b-poly(l-lactide-co-ε-caprolactone) (PELCL) by three different peptides for regulation of VECs were studied in order to obtain ideal bioactive biomaterials as small diameter vascular grafts. QK (a mimetic peptide to vascular endothelial growth factor), Arg-Glu-Asp-Val (REDV, a specific adhesive peptide to VECs) and Val-Ala-Pro-Gly (VAPG, a specific adhesive peptide to vascular smooth muscle cells) were investigated. Surface properties of the modified membranes and the response of VECs were verified. It was found that protein adsorption and platelet adhesion were effectively suppressed with the introduction of QK, REDV or VAPG peptides on the PELCL electrospun membranes. Both QK- and REDV-modified electrospun membranes could accelerate the proliferation of VECs in the first 9days, and the QK-modified electrospun membrane promoted cell proliferation more significantly than the REDV-modified one. The REDV-modified PELCL membrane was the most favorable for VECs adhesion than QK- and VAPG-modified membranes. It was suggested that QK- or REDV-modified PELCL electrospun membranes may have great potential applications in cardiovascular biomaterials for rapid endothelialization in situ. Copyright © 2016 Elsevier B.V. All rights reserved.

Multiscale Architectures and Parallel Algorithms for Video Object Tracking

DTIC Science & Technology

2011-10-01

0 4 : if FIFO1 contains nDt frames then 5: Partition data into blocks. 6: Put SPE control block information...char buf 4 = FF; vec to r unsigned char buf 5 = FF; vec to r unsigned char buf 6 = FF; vec to r unsigned char buf 7 = FF; for ( j = 0 ; j < s i z e ; j...Public Release; Distribution Unlimited 8 7 u 6 ill :J (;) 5 E -;::; c 0 4 ~ u Q) X 3 Q) 8 7 6 u Q) Ul 5 :J (;) E :;::; 4 c 0

Directed polymer in a random medium of dimension 1+1 and 1+3: weights statistics in the low temperature phase

NASA Astrophysics Data System (ADS)

Monthus, Cécile; Garel, Thomas

2007-03-01

We consider the low temperature T

Use of polymerase chain reaction technique to confirm VecTest screening results in Plasmodium falciparum and Plasmodium vivax VK 210 laboratory-infected Anopheles stephensi mosquitoes.

PubMed

Santos-Ciminera, Patricia D; Acheé, Nicole L; Quinnan, Gerald V; Roberts, Donald R

2004-09-01

We evaluated polymerase chain reaction (PCR) to confirm immunoassays for malaria parasites in mosquito pools after a failure to detect malaria with PCR during an outbreak in which pools tested positive using VecTest and enzyme-linked immunosorbent assay (ELISA). We combined VecTest, ELISA, and PCR to detect Plasmodium falciparum and Plasmodium vivax VK 210. Each mosquito pool, prepared in triplicate, consisted of 1 exposed Anopheles stephensi and up to 9 unfed mosquitoes. The results of VecTest and ELISA were concordant. DNA from a subset of the pools, 1 representative of each ratio of infected to uninfected mosquitoes, was extracted and used as template in PCR. All P. vivax pools were PCR positive but some needed additional processing for removal of apparent inhibitors before positive results were obtained. One of the pools selected for P. falciparum was negative by PCR, probably because of losses or contamination during DNA extraction; 2 remaining pools at this ratio were PCR positive. Testing pools by VecTest, ELISA, and PCR is feasible, and PCR is useful for confirmation of immunoassays. An additional step might be needed to remove potential inhibitors from pools prior to PCR.

Generalized Jastrow Variational Method for Liquid HELIUM-3-HELIUM-4 Mixtures at T = 0 K.

NASA Astrophysics Data System (ADS)

Mirabbaszadeh, Kavoos

Microscopic theory of dilute liquid { ^3 He}-{^4 He} mixtures is of great interest, because it provides a physical realization of a nearly degenerate weakly interacting Fermion system. An understanding of properties of the mixtures has received considerable attention both theoretically and experimentally over the past thirty years. We present here a variational procedure based on the Jastrow function for the ground state of {^3 He}- {^4 He} mixtures by minimizing the total energy of the mixture using the hypernetted-chain (HNC) approximation and the Percus-Yevick (PY) approximation for the two body correlation functions. Our goal is to compute from first principles the internal energy of the system and the various two body correlation functions at various densities and compare the results with experiment. The Jastrow variational method for the ground state energy of liquid {^4 He} consists of the following ansatz for the wave function Psi_alpha {rm(vec r_{1 alpha},} {vec r_{2alpha},} dots, {vec r_{N _alpha})} = prod _{rm i < j} {rm f_ {alphaalpha}(r_{ij}). } For a {^3 He } system the corresponding ansatz is Psi_beta {rm( vec r_{1beta},} {vec r_{2beta },} dots, {vec r_{N_beta})} = {[prod _{i < j} f_{betabeta }(r_{ij})]} Phi {rm( vec r_{1beta},} {vec r_{2beta },} dots, {vec r_{Nbeta}),} where Phi is a Slater determinant of plane waves for the ground state of the Fermion system. The total energy per particle can be written in the form: E = x_sp{alpha}{2} E_{alphaalpha} + x_sp{beta}{2 }E_{betabeta } + 2x_{alpha} x_{beta}E _{alphabeta}, where E_{alphaalpha} , E_{betabeta} , E_{alphabeta} are unknown parameters to be determined from a microscopic theory. Using the Jastrow wave function Psi for the mixture, a general expression is given for the ground state energy in terms of the two body potential and two and three body correlation functions. The Kirkwood Super-position Approximation (KSA) is used for the three-body correlation functions. The antisymmetry of the wave function for Fermions is incorporated following the procedure given earlier by Lado, Inguva and Smith. This procedure for treating the antisymmetry of the wave function simplifies the equations for the two-body correlation functions considerably. The equations for the correlation functions are solved in the hypernetted-chain approximation. Once the two-particle correlation functions for the mixture ( ^3He-^4He) have been obtained, the energy is minimized with respect to the variational parameters involved in the Jastrow wave function. The binding energy and the optimal correlation functions are then obtained as a function of the concentration of ^3He atoms in the mixture. (Abstract shortened with permission of author.).

The Natural Protective Mechanism Against Hyperglycemia in Vascular Endothelial Cells

PubMed Central

Riahi, Yael; Sin-Malia, Yoav; Cohen, Guy; Alpert, Evgenia; Gruzman, Arie; Eckel, Juergen; Staels, Bart; Guichardant, Michel; Sasson, Shlomo

2010-01-01

OBJECTIVE Vascular endothelial cells (VECs) downregulate their rate of glucose uptake in response to hyperglycemia by decreasing the expression of their typical glucose transporter GLUT-1. Hitherto, we discovered critical roles for the protein calreticulin and the arachidonic acid–metabolizing enzyme 12-lipoxygenase in this autoregulatory process. The hypothesis that 4-hydroxydodeca-(2E,6Z)-dienal (4-HDDE), the peroxidation product of 12-lipoxygenase, mediates this downregulatory mechanism by activating peroxisome proliferator–activated receptor (PPAR) δ was investigated. RESEARCH DESIGN AND METHODS Effects of 4-HDDE and PPARδ on the glucose transport system and calreticulin expression in primary bovine aortic endothelial cells were evaluated by pharmacological and molecular interventions. RESULTS Using GW501516 (PPARδ agonist) and GSK0660 (PPARδ antagonist), we discovered that high-glucose–induced downregulation of the glucose transport system in VECs is mediated by PPARδ. A PPAR-sensitive luciferase reporter assay in VECs revealed that high glucose markedly increased luciferase activity, while GSK0660 abolished it. High-performance liquid chromatography analysis showed that high-glucose incubation substantially elevated the generation of 4-HDDE in VECs. Treatment of VECs, exposed to normal glucose, with 4-HDDE mimicked high glucose and downregulated the glucose transport system and increased calreticulin expression. Like high glucose, 4-HDDE significantly activated PPARδ in cells overexpressing human PPAR (hPPAR)δ but not hPPARα, -γ1, or -γ2. Moreover, silencing of PPARδ prevented high-glucose–dependent alterations in GLUT-1 and calreticulin expression. Finally, specific binding of PPARδ to a PPAR response element in the promoter region of the calreticulin gene was identified by utilizing a specific chromatin immunoprecipitation assay. CONCLUSIONS Collectively, our data show that 4-HDDE plays a central role in the downregulation of glucose uptake in VECs by activating PPARδ. PMID:20107107

Wavelet transform approach for fitting financial time series data

NASA Astrophysics Data System (ADS)

Ahmed, Amel Abdoullah; Ismail, Mohd Tahir

2015-10-01

This study investigates a newly developed technique; a combined wavelet filtering and VEC model, to study the dynamic relationship among financial time series. Wavelet filter has been used to annihilate noise data in daily data set of NASDAQ stock market of US, and three stock markets of Middle East and North Africa (MENA) region, namely, Egypt, Jordan, and Istanbul. The data covered is from 6/29/2001 to 5/5/2009. After that, the returns of generated series by wavelet filter and original series are analyzed by cointegration test and VEC model. The results show that the cointegration test affirms the existence of cointegration between the studied series, and there is a long-term relationship between the US, stock markets and MENA stock markets. A comparison between the proposed model and traditional model demonstrates that, the proposed model (DWT with VEC model) outperforms traditional model (VEC model) to fit the financial stock markets series well, and shows real information about these relationships among the stock markets.

Virtue Existential Career Model: A Dialectic and Integrative Approach Echoing Eastern Philosophy

PubMed Central

Liu, Shu-Hui; Hung, Jui-Ping; Peng, Hsin-I; Chang, Chia-Hui; Lu, Yi-Jen

2016-01-01

Our Virtue Existential Career (VEC) model aims at complementing western modernism and postmodernism career theories with eastern philosophy. With dialectical philosophy and virtue-practice derived from the Classic of Changes, the VEC theoretical foundation incorporates merits from Holland typology, Minnesota Theory of Work Adjustment, Social Cognitive Career Theory, Meaning Therapy, Narrative Approach Career Counseling, and Happenstance Learning Theory. While modernism considers a matched job as an ideal career vision and prefers rational strategies (controlling and realizing) to achieve job security; postmodernism prefers appreciating and adapting strategies toward openness and appreciates multiple possible selves and occupations, our model pursues a blending of security and openness via controlling-and-realizing and appreciating-and-adapting interwoven with each other in a dialectical and harmonious way. Our VEC counseling prototype aims at a secular goal of living on the earth with ways and harmony (安身以法以和) and an ultimate end to spiral up to the wisdom of living up to the way of heaven (天道) with mind and virtue (立命以心以德). A VEC counseling process of five major career strategies, metaphorical stories of qian and kun, and experiential activities are developed to deliver VEC concepts. The VEC model and prototype presented in this research is the product of an action research following Lewin's (1946) top-to-down model. Situated structure analyses were conducted to further investigate the adequacy of this version of VEC model and prototype. Data from two groups (one for stranded college graduates and the other for growing college students) revealed empirical supports. Yang type of career praxes tends to induce actualization, which resulting in realistic goals and concrete action plans; yin type of career praxes tends to increase self-efficacy, which resulting in positive attitude toward current situatedness and future development. Acceptance and dialectic thinking often result from yin-yang-blending career praxes. Growing developers benefit from a strategy sequence of yang-yin-synthesized; stranded developers from a strategy sequence of yin-yang-synthesized. Our contributions and limitations are discussed in the context of developing indigenous career theories and practices for a globalized and ever-changing world. PMID:27895604

Virtue Existential Career Model: A Dialectic and Integrative Approach Echoing Eastern Philosophy.

PubMed

Liu, Shu-Hui; Hung, Jui-Ping; Peng, Hsin-I; Chang, Chia-Hui; Lu, Yi-Jen

2016-01-01

Our Virtue Existential Career (VEC) model aims at complementing western modernism and postmodernism career theories with eastern philosophy. With dialectical philosophy and virtue-practice derived from the Classic of Changes , the VEC theoretical foundation incorporates merits from Holland typology, Minnesota Theory of Work Adjustment, Social Cognitive Career Theory, Meaning Therapy, Narrative Approach Career Counseling, and Happenstance Learning Theory. While modernism considers a matched job as an ideal career vision and prefers rational strategies ( controlling and realizing ) to achieve job security; postmodernism prefers appreciating and adapting strategies toward openness and appreciates multiple possible selves and occupations, our model pursues a blending of security and openness via controlling-and-realizing and appreciating-and-adapting interwoven with each other in a dialectical and harmonious way. Our VEC counseling prototype aims at a secular goal of living on the earth with ways and harmony () and an ultimate end to spiral up to the wisdom of living up to the way of heaven () with mind and virtue (). A VEC counseling process of five major career strategies, metaphorical stories of qian and kun , and experiential activities are developed to deliver VEC concepts. The VEC model and prototype presented in this research is the product of an action research following Lewin's (1946) top-to-down model. Situated structure analyses were conducted to further investigate the adequacy of this version of VEC model and prototype. Data from two groups (one for stranded college graduates and the other for growing college students) revealed empirical supports. Y ang type of career praxes tends to induce actualization, which resulting in realistic goals and concrete action plans; yin type of career praxes tends to increase self-efficacy, which resulting in positive attitude toward current situatedness and future development. Acceptance and dialectic thinking often result from yin -y ang- blending career praxes. Growing developers benefit from a strategy sequence of yang-yin -synthesized; stranded developers from a strategy sequence of yin-yang -synthesized. Our contributions and limitations are discussed in the context of developing indigenous career theories and practices for a globalized and ever-changing world.

Direct conversion of human amniotic cells into endothelial cells without transitioning through a pluripotent state

PubMed Central

Ginsberg, Michael; Schachterle, William; Shido, Koji; Rafii, Shahin

2016-01-01

Endothelial cells (ECs) have essential roles in organ development and regeneration, and therefore they could be used for regenerative therapies. However, generation of abundant functional endothelium from pluripotent stem cells has been difficult because ECs generated by many existing strategies have limited proliferative potential and display vascular instability. The latter difficulty is of particular importance because cells that lose their identity over time could be unsuitable for therapeutic use. Here, we describe a 3-week platform for directly converting human mid-gestation lineage-committed amniotic fluid–derived cells (ACs) into a stable and expandable population of vascular ECs (rAC-VECs) without using pluripotency factors. By transient expression of the ETS transcription factor ETV2 for 2 weeks and constitutive expression the ETS transcription factors FLI1 and ERG1, concomitant with TGF-β inhibition for 3 weeks, epithelial and mesenchymal ACs are converted, with high efficiency, into functional rAC-VECs. These rAC-VECs maintain their vascular repertoire and morphology over numerous passages in vitro, and they form functional vessels when implanted in vivo. rAC-VECs can be detected in recipient mice months after implantation. Thus, rAC-VECs can be used to establish a cellular platform to uncover the molecular determinants of vascular development and heterogeneity and potentially represent ideal ECs for the treatment of regenerative disorders. PMID:26540589

Aortic calcified particles modulate valvular endothelial and interstitial cells.

PubMed

van Engeland, Nicole C A; Bertazzo, Sergio; Sarathchandra, Padmini; McCormack, Ann; Bouten, Carlijn V C; Yacoub, Magdi H; Chester, Adrian H; Latif, Najma

Normal and calcified human valve cusps, coronary arteries, and aortae harbor spherical calcium phosphate microparticles of identical composition and crystallinity, and their role remains unknown. The objective was to examine the direct effects of isolated calcified particles on human valvular cells. Calcified particles were isolated from healthy and diseased aortae, characterized, quantitated, and applied to valvular endothelial cells (VECs) and interstitial cells (VICs). Cell differentiation, viability, and proliferation were analyzed. Particles were heterogeneous, differing in size and shape, and were crystallized as calcium phosphate. Diseased donors had significantly more calcified particles compared to healthy donors (P<.05), but there were no differences between the composition of the particles from healthy and diseased donors. VECs treated with calcified particles showed a significant decrease in CD31 and VE-cadherin and an increase in von Willebrand factor expression, P<.05. There were significantly increased α-SMA and osteopontin in treated VICs (P<.05), significantly decreased VEC and VIC viability (P<.05), and significantly increased number of terminal deoxynucleotidyl transferase dUTP nick end labeling-positive VECs (P<.05) indicating apoptosis when treated with the calcified particles. Isolated calcified particles from human aortae are not innocent bystanders but induce a phenotypical and pathological change of VECs and VICs characteristic of activated and pathological cells. Therapy tailored to reduce these calcified particles should be investigated. Copyright © 2017 Elsevier Inc. All rights reserved.

Side-Specific Endothelial-Dependent Regulation of Aortic Valve Calcification

PubMed Central

Richards, Jennifer; El-Hamamsy, Ismail; Chen, Si; Sarang, Zubair; Sarathchandra, Padmini; Yacoub, Magdi H.; Chester, Adrian H.; Butcher, Jonathan T.

2014-01-01

Arterial endothelial cells maintain vascular homeostasis and vessel tone in part through the secretion of nitric oxide (NO). In this study, we determined how aortic valve endothelial cells (VEC) regulate aortic valve interstitial cell (VIC) phenotype and matrix calcification through NO. Using an anchored in vitro collagen hydrogel culture system, we demonstrate that three-dimensionally cultured porcine VIC do not calcify in osteogenic medium unless under mechanical stress. Co-culture with porcine VEC, however, significantly attenuated VIC calcification through inhibition of myofibroblastic activation, osteogenic differentiation, and calcium deposition. Incubation with the NO donor DETA-NO inhibited VIC osteogenic differentiation and matrix calcification, whereas incubation with the NO blocker l-NAME augmented calcification even in 3D VIC–VEC co-culture. Aortic VEC, but not VIC, expressed endothelial NO synthase (eNOS) in both porcine and human valves, which was reduced in osteogenic medium. eNOS expression was reduced in calcified human aortic valves in a side-specific manner. Porcine leaflets exposed to the soluble guanylyl cyclase inhibitor ODQ increased osteocalcin and α-smooth muscle actin expression. Finally, side-specific shear stress applied to porcine aortic valve leaflet endothelial surfaces increased cGMP production in VEC. Valve endothelial-derived NO is a natural inhibitor of the early phases of valve calcification and therefore may be an important regulator of valve homeostasis and pathology. PMID:23499458

47 CFR Appendix 2 to Part 97 - VEC Regions

Code of Federal Regulations, 2014 CFR

2014-10-01

... SERVICE Pt. 97, App. 2 Appendix 2 to Part 97—VEC Regions 1. Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island and Vermont. 2. New Jersey and New York. 3. Delaware, District of Columbia, Maryland... and Virginia. 5. Arkansas, Louisiana, Mississippi, New Mexico, Oklahoma and Texas. 6. California. 7...

Quantum Computational Geodesics

DTIC Science & Technology

2010-01-01

dtU (t)†  unvec κt   t ∫ 0 drκ−1r vec C(r...U(t). (209) If J(T ) = 0 in equation 209, then d dt J(0) = j−1T   T ∫ 0 dtU (t)†  unvec κt   t ∫ 0 drκ−1r vec C(r)    U(t)   . (210...equation 211, one obtains the so-called geodesic derivative (1) d dq Hq(0) = j −1 T   T ∫ 0 dtU (t)†unvec   κt   t ∫ 0 drκ−1r vec C(r)   

Photoproduction of Λ and Σ 0 hyperons using linearly polarized photons

DOE PAGES

Paterson, C. A.; Ireland, D. G.; Livingston, K.; ...

2016-06-08

Measurements of polarization observables for the reactionsmore » $$\\vec{\\gamma} p \\rightarrow K^+ \\Lambda$$ and $$\\vec{\\gamma} p \\rightarrow K^+ \\Sigma^0$$ have been performed. This is part of a programme of measurements designed to study the spectrum of baryon resonances. The accurate measurement of several polarization observables provides tight constraints for phenomenological fits. Beam-recoil observables for the $$\\vec{\\gamma} p \\rightarrow K^+ \\Sigma^0$$ reaction have not been reported before now. Furthermore, the measurements were carried out using linearly polarized photon beams and the CLAS detector at the Thomas Jefferson National Accelerator Facility. The energy range of the results is 1.71GeV.« less

Effect of Herbal Medicine on Vaginal Epithelial Cells: A Systematic Review and Meta-analysis.

PubMed

Rahmani, Yousef; Chaleh, Khadijeh Chaleh; Shahmohammadi, Afshar; Safari, Shahla

2018-04-01

The present meta-analysis aimed to assess the effect of the herbal medicine on the vaginal epithelial cells (VECs) among the menopausal subjects. The literature related to VECs exposed to various herbal medicines in menopausal women were searched on three databases, MEDLINE (1966-August 2017), Scopus (1990-August 2017) and Cochrane Library (Cochrane Central Register of Controlled Trials; 2014). Totally, the meta-analysis was conducted on 11 randomised controlled trials. Based on the findings, the standardized mean difference (SMD) of maturation value (MV) was observed to be elevated by 0.48% (95% interval confidence [CI], 0.108-0.871; P = 0.012), as well as the heterogeneity was high (I 2 = 84%; P < 0.001). The MV revealed a significant increase in soy group (SMD, 0.358; 95% CI, 0.073-0.871; P = 0.014) compared to the control group. The herbal medicines exhibited a statistically significant effect on the VECs. A significant effect on the VECs was also found in the subgroup analysis of the patients, who received soy. However, further and extensive studies are required to achieve reliable outcomes.

Innate immunity in the vagina (part I): estradiol inhibits HBD2 and elafin secretion by human vaginal epithelial cells.

PubMed

Patel, Mickey V; Fahey, John V; Rossoll, Richard M; Wira, Charles R

2013-05-01

Vaginal epithelial cells (VEC) are the first line of defense against incoming pathogens in the female reproductive tract. Their ability to produce the anti-HIV molecules elafin and HBD2 under hormonal stimulation is unknown. Vaginal epithelial cells were recovered using a menstrual cup and cultured overnight prior to treatment with estradiol (E₂), progesterone (P₄) or a panel of selective estrogen response modulators (SERMs). Conditioned media were recovered and analyzed for protein concentration and anti-HIV activity. E₂ significantly decreased the secretion of HBD2 and elafin by VEC over 48 hrs, while P4 and the SERMs (tamoxifen, PHTTP, ICI or Y134) had no effect. VEC conditioned media from E₂ -treated cells had no anti-HIV activity, while that from E₂ /P₄ -treated cells significantly inhibited HIV-BaL infection. The menstrual cup allows for effective recovery of primary VEC. Their production of HBD2 and elafin is sensitive to E₂, suggesting that innate immune protection varies in the vagina across the menstrual cycle. © 2013 John Wiley & Sons A/S.

Mechanism of the protective effects of the combined treatment with rhynchophylla total alkaloids and sinapine thiocyanate against a prothrombotic state caused by vascular endothelial cell inflammatory damage

PubMed Central

Li, Yunlun; Zhang, Xinya; Yang, Wenqing; Li, Chao; Chu, Yanjun; Jiang, Haiqiang; Shen, Zhenzhen

2017-01-01

The aim of the present study was to investigate the effect and the underlying mechanism of the combined treatment of rhynchophylla total alkaloids (RTA) and sinapine thiocyanate for protection against a prothrombotic state (PTS) associated with the tumor necrosis factor-alpha (TNF-α)-induced inflammatory injury of vascular endothelial cells (VECs). A TNF-α-induced VEC inflammatory injury model was established, and cell morphology of VECs was evaluated using scanning electron microscopy. In addition, reverse transcription-quantitative polymerase chain reaction and western blot analysis were performed to examine the mRNA and protein expression of coagulation-related factors, including nuclear factor-κB (NF-κB), transforming growth factor-β1 (TGF-β1), tissue factor (TF), plasminogen activator inhibitor (PAI-1), protease-activation receptors (PAR-1) and protein kinase C (PKC-α) in VECs. Combined treatment with RTA and sinapine thiocyanate was demonstrated to reduce, to a varying extent, the mRNA and protein expression of NF-κB, TGF-β1, TF, PAR-1, PKC-α and PAI-1. Furthermore, combined treatment with RTA and sinapine thiocyanate was able to downregulate the expression of coagulation-related factors in injured VECs, thereby inhibiting the PTS induced by vascular endothelial injury. The underlying mechanism is partially associated with the TF-mediated activation of the thrombin-receptor signaling pathway that suppresses coagulation during inflammation and balances fibrinolysis in order to inhibit fibrin generation and deposition. PMID:28587383

Inhibitory Effect of Natural Anti-Inflammatory Compounds on Cytokines Released by Chronic Venous Disease Patient-Derived Endothelial Cells

PubMed Central

Tisato, Veronica; Zauli, Giorgio; Rimondi, Erika; Gianesini, Sergio; Brunelli, Laura; Menegatti, Erica; Zamboni, Paolo; Secchiero, Paola

2013-01-01

Large vein endothelium plays important roles in clinical diseases such as chronic venous disease (CVD) and thrombosis; thus to characterize CVD vein endothelial cells (VEC) has a strategic role in identifying specific therapeutic targets. On these bases we evaluated the effect of the natural anti-inflammatory compounds α-Lipoic acid and Ginkgoselect phytosome on cytokines/chemokines released by CVD patient-derived VEC. For this purpose, we characterized the levels of a panel of cytokines/chemokines (n = 31) in CVD patients' plasma compared to healthy controls and their release by VEC purified from the same patients, in unstimulated and TNF-α stimulated conditions. Among the cytokines/chemokines released by VEC, which recapitulated the systemic profile (IL-8, TNF-α, GM-CSF, INF-α2, G-CSF, MIP-1β, VEGF, EGF, Eotaxin, MCP-1, CXCL10, PDGF, and RANTES), we identified those targeted by ex vivo treatment with α-Lipoic acid and/or Ginkgoselect phytosome (GM-CSF, G-CSF, CXCL10, PDGF, and RANTES). Finally, by investigating the intracellular pathways involved in promoting the VEC release of cytokines/chemokines, which are targeted by natural anti-inflammatory compounds, we documented that α-Lipoic acid significantly counteracted TNF-α-induced NF-κB and p38/MAPK activation while the effects of Ginkgo biloba appeared to be predominantly mediated by Akt. Our data provide new insights into the molecular mechanisms of CVD pathogenesis, highlighting new potential therapeutic targets. PMID:24489443

Mechanism of the protective effects of the combined treatment with rhynchophylla total alkaloids and sinapine thiocyanate against a prothrombotic state caused by vascular endothelial cell inflammatory damage.

PubMed

Li, Yunlun; Zhang, Xinya; Yang, Wenqing; Li, Chao; Chu, Yanjun; Jiang, Haiqiang; Shen, Zhenzhen

2017-06-01

The aim of the present study was to investigate the effect and the underlying mechanism of the combined treatment of rhynchophylla total alkaloids (RTA) and sinapine thiocyanate for protection against a prothrombotic state (PTS) associated with the tumor necrosis factor-alpha (TNF-α)-induced inflammatory injury of vascular endothelial cells (VECs). A TNF-α-induced VEC inflammatory injury model was established, and cell morphology of VECs was evaluated using scanning electron microscopy. In addition, reverse transcription-quantitative polymerase chain reaction and western blot analysis were performed to examine the mRNA and protein expression of coagulation-related factors, including nuclear factor-κB (NF-κB), transforming growth factor-β1 (TGF-β1), tissue factor (TF), plasminogen activator inhibitor (PAI-1), protease-activation receptors (PAR-1) and protein kinase C (PKC-α) in VECs. Combined treatment with RTA and sinapine thiocyanate was demonstrated to reduce, to a varying extent, the mRNA and protein expression of NF-κB, TGF-β1, TF, PAR-1, PKC-α and PAI-1. Furthermore, combined treatment with RTA and sinapine thiocyanate was able to downregulate the expression of coagulation-related factors in injured VECs, thereby inhibiting the PTS induced by vascular endothelial injury. The underlying mechanism is partially associated with the TF-mediated activation of the thrombin-receptor signaling pathway that suppresses coagulation during inflammation and balances fibrinolysis in order to inhibit fibrin generation and deposition.

Vaginal innate immune mediators are modulated by a water extract of Houttuynia cordata Thunb.

PubMed

Satthakarn, Surada; Hladik, Florian; Promsong, Aornrutai; Nittayananta, Wipawee

2015-06-16

Vaginal epithelial cells (VECs) produce antimicrobial peptides including human β-defensin 2 (hBD2) and secretory leukocyte protease inhibitor (SLPI), as well as cytokines and chemokines that play vital roles in mucosal innate immunity of the female reproductive tract. Houttuynia cordata Thunb (H. cordata), a herbal plant found in Asia, possesses various activities including antimicrobial activity and anti-inflammation. As inflammation and infection are commonly found in female reproductive tract, we aimed to investigate the effects of H. cordata water extract in modulating innate immune factors produced by VECs. Primary human VECs were cultured and treated with H. cordata at a concentration ranging from 25-200 μg/ml for 6 or 18 h. After treatment, the cells and culture supernatants were harvested. The expression of hBD2 and SLPI mRNA was evaluated by quantitative real-time reverse transcription PCR. Levels of secreted hBD2 and SLPI as well as cytokines and chemokines in the supernatants were measured by ELISA and Luminex assay, respectively. Cytotoxicity of the extract on VECs was assessed by CellTiter-Blue Cell Viability Assay. H. cordata did not cause measurable toxicity on VECs after exposure for 18 h. The expression of hBD2 and SLPI mRNA as well as the secreted hBD2 protein were increased in response to H. cordata exposure for 18 h when compared to the untreated controls. However, treatment with the extract for 6 h had only slight effects on the mRNA expression of hBD2 and SLPI. The secretion of IL-2 and IL-6 proteins by VECs was also increased, while the secretion of CCL5 was decreased after treatment with the extract for 18 h. Treatment with H. cordata extract had some effects on the secretion of IL-4, IL-8, CCL2, and TNF-α, but not statistically significant. H. cordata water extract modulates the expression of antimicrobial peptides and cytokines produced by VECs, which play an important role in the mucosal innate immunity in the female reproductive tract. Our findings suggest that H. cordata may have immunomodulatory effects on the vaginal mucosa. Further studies should be performed in vivo to determine if it can enhance mucosal immune defenses against microbial pathogens.

An online analytical processing multi-dimensional data warehouse for malaria data

PubMed Central

Madey, Gregory R; Vyushkov, Alexander; Raybaud, Benoit; Burkot, Thomas R; Collins, Frank H

2017-01-01

Abstract Malaria is a vector-borne disease that contributes substantially to the global burden of morbidity and mortality. The management of malaria-related data from heterogeneous, autonomous, and distributed data sources poses unique challenges and requirements. Although online data storage systems exist that address specific malaria-related issues, a globally integrated online resource to address different aspects of the disease does not exist. In this article, we describe the design, implementation, and applications of a multi-dimensional, online analytical processing data warehouse, named the VecNet Data Warehouse (VecNet-DW). It is the first online, globally-integrated platform that provides efficient search, retrieval and visualization of historical, predictive, and static malaria-related data, organized in data marts. Historical and static data are modelled using star schemas, while predictive data are modelled using a snowflake schema. The major goals, characteristics, and components of the DW are described along with its data taxonomy and ontology, the external data storage systems and the logical modelling and physical design phases. Results are presented as screenshots of a Dimensional Data browser, a Lookup Tables browser, and a Results Viewer interface. The power of the DW emerges from integrated querying of the different data marts and structuring those queries to the desired dimensions, enabling users to search, view, analyse, and store large volumes of aggregated data, and responding better to the increasing demands of users. Database URL https://dw.vecnet.org/datawarehouse/ PMID:29220463

Assessment of the relationship of government spending on social assistance programs with Brazilian macroeconomic variables

NASA Astrophysics Data System (ADS)

de Senna, Viviane; Souza, Adriano Mendonça

2016-11-01

Since the 1988 Federal Constitution social assistance has become a duty of the State and a right to everyone, guaranteeing the population a dignified life. To ensure these rights federal government has created programs that can supply the main needs of people in extreme poverty. Among the programs that provide social assistance to the population, the best known are the ;Bolsa Família; Program - PBF and the Continuous Cash Benefit - Continuous Cash Benefit - BPC. This research's main purpose is to analyze the relationship between the main macroeconomic variables and the Federal government spending on social welfare policy in the period from January 2004 to August 2014. The used methodologies are the Vector auto regression model - VAR and Error Correction Vector - VEC. The conclusion, was that there is a meaningful relationship between macroeconomic variables and social assistance programs. This indicates that if the government takes a more abrupt resolution in changing the existing programs it will result in fluctuations in the main macroeconomic variables interfering with the stability of Brazilian domestic economy up to twelve months.

Visualization of Circuit Card EM Fields.

DTIC Science & Technology

1998-03-31

0.010 - Photoimageable (Min.): 0.005 «Located at 7845 -J Airpark Road; Gaithersburg, Maryland 20879. 301-977-0303, http://www.capitalelectro.com...rlabelC«’); tit-. Ch .3SO; print -dep« fig_conn.h36.ep«; fignre; X differential node rel.diff_vec-0; h_vec«0.6:0.2:6.0; len_h«length(h_ve_); for i

Effect of Herbal Medicine on Vaginal Epithelial Cells: A Systematic Review and Meta-analysis

PubMed Central

Rahmani, Yousef; Chaleh, Khadijeh Chaleh; Shahmohammadi, Afshar

2018-01-01

Objectives The present meta-analysis aimed to assess the effect of the herbal medicine on the vaginal epithelial cells (VECs) among the menopausal subjects. Methods The literature related to VECs exposed to various herbal medicines in menopausal women were searched on three databases, MEDLINE (1966–August 2017), Scopus (1990–August 2017) and Cochrane Library (Cochrane Central Register of Controlled Trials; 2014). Results Totally, the meta-analysis was conducted on 11 randomised controlled trials. Based on the findings, the standardized mean difference (SMD) of maturation value (MV) was observed to be elevated by 0.48% (95% interval confidence [CI], 0.108–0.871; P = 0.012), as well as the heterogeneity was high (I2 = 84%; P < 0.001). The MV revealed a significant increase in soy group (SMD, 0.358; 95% CI, 0.073–0.871; P = 0.014) compared to the control group. Conclusions The herbal medicines exhibited a statistically significant effect on the VECs. A significant effect on the VECs was also found in the subgroup analysis of the patients, who received soy. However, further and extensive studies are required to achieve reliable outcomes. PMID:29765922

Innate Immunity in the Vagina (Part I): Estradiol Inhibits HBD2 and Elafin Secretion by Human Vaginal Epithelial Cells

PubMed Central

Patel, Mickey V.; Fahey, John V.; Rossoll, Richard M.; Wira, Charles R.

2013-01-01

Problem Vaginal epithelial cells (VEC) are the first line of defense against incoming pathogens in the female reproductive tract. Their ability to produce the anti-HIV molecules elafin and HBD2 under hormonal stimulation is unknown. Method of study Vaginal epithelial cells were recovered using a menstrual cup and cultured overnight prior to treatment with estradiol (E2), progesterone (P4) or a panel of selective estrogen response modulators (SERMs). Conditioned media were recovered and analyzed for protein concentration and anti-HIV activity. Results E2 significantly decreased the secretion of HBD2 and elafin by VEC over 48 hrs, while P4 and the SERMs (tamoxifen, PHTTP, ICI or Y134) had no effect. VEC conditioned media from E2-treated cells had no anti-HIV activity, while that from E2/P4-treated cells significantly inhibited HIV-BaL infection. Conclusion The menstrual cup allows for effective recovery of primary VEC. Their production of HBD2 and elafin is sensitive to E2, suggesting that innate immune protection varies in the vagina across the menstrual cycle. PMID:23398087

Measurement of target and double-spin asymmetries for the $$\\vec e\\vec p\\to e\\pi^+ (n)$$ reaction in the nucleon resonance region at low $Q^2$

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, X.; Adhikari, K. P.; Bosted, P.

We report measurements of target- and double-spin asymmetries for the exclusive channelmore » $$\\vec e\\vec p\\to e\\pi^+ (n)$$ in the nucleon resonance region at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). These asymmetries were extracted from data obtained using a longitudinally polarized NH$$_3$$ target and a longitudinally polarized electron beam with energies 1.1, 1.3, 2.0, 2.3 and 3.0 GeV. The new results are consistent with previous CLAS publications but are extended to a low $Q^2$ range from $0.0065$ to $0.35$ (GeV$/c$)$^2$. The $Q^2$ access was made possible by a custom-built Cherenkov detector that allowed the detection of electrons for scattering angles as low as $$6^\\circ$$. These results are compared with the unitary isobar models JANR and MAID, the partial-wave analysis prediction from SAID and the dynamic model DMT. In many kinematic regions our results, in particular results on the target asymmetry, help to constrain the polarization-dependent components of these models.« less

Polarization Transfer in the Reaction 4He($$\\vec{v}$$,e'$$\\vec{p}$$) 3H in the Quasielastic Scattering Region

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dieterich, Sonja

2002-05-01

There has been a longstanding issue concerning possible nucleon modifications in a (dense) nuclear medium. Polarization transfer data for exclusive quasielastic electron scattering are a sensitive to the ratio of the electric and magnetic nucleon form factors in the medium. Although proper interpretation of the results requires accounting for such effects as final state interactions and meson exchange currents, their effect on polarization transfer is predicted to be small. Studies of model dependencies, e.g., the off-shell current operator and spinor distortions, have been done. Final results of a measurement of polarization transfer in the 4He(more » $$\\vec{v}$$,e'$$\\vec{p}$$) 3H reaction will be discussed. The experiments were carried out at MAMI, Mainz at a Q 2 of 0.4 GeV 2 and at the Thomas Jefferson Lab, Newport News, Virginia at the Q 2 values 0.5, 1.0, 1.6 and 2.6 GeV 2. Measured values of the transferred and induced polarization are compared with various theoretical calculations. The experiment showed a difference between the fully relativistic model with may indicate medium modifications of the form factor.« less

Measurement of target and double-spin asymmetries for the $$\\vec e\\vec p\\to e\\pi^+ (n)$$ reaction in the nucleon resonance region at low $Q^2$

DOE PAGES

Zheng, X.; Adhikari, K. P.; Bosted, P.; ...

2016-10-19

We report measurements of target- and double-spin asymmetries for the exclusive channelmore » $$\\vec e\\vec p\\to e\\pi^+ (n)$$ in the nucleon resonance region at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). These asymmetries were extracted from data obtained using a longitudinally polarized NH$$_3$$ target and a longitudinally polarized electron beam with energies 1.1, 1.3, 2.0, 2.3 and 3.0 GeV. The new results are consistent with previous CLAS publications but are extended to a low $Q^2$ range from $0.0065$ to $0.35$ (GeV$/c$)$^2$. The $Q^2$ access was made possible by a custom-built Cherenkov detector that allowed the detection of electrons for scattering angles as low as $$6^\\circ$$. These results are compared with the unitary isobar models JANR and MAID, the partial-wave analysis prediction from SAID and the dynamic model DMT. In many kinematic regions our results, in particular results on the target asymmetry, help to constrain the polarization-dependent components of these models.« less

A Novel Recommendation System to Match College Events and Groups to Students

NASA Astrophysics Data System (ADS)

Qazanfari, K.; Youssef, A.; Keane, K.; Nelson, J.

2017-10-01

With the recent increase in data online, discovering meaningful opportunities can be time-consuming and complicated for many individuals. To overcome this data overload challenge, we present a novel text-content-based recommender system as a valuable tool to predict user interests. To that end, we develop a specific procedure to create user models and item feature-vectors, where items are described in free text. The user model is generated by soliciting from a user a few keywords and expanding those keywords into a list of weighted near-synonyms. The item feature-vectors are generated from the textual descriptions of the items, using modified tf-idf values of the users’ keywords and their near-synonyms. Once the users are modeled and the items are abstracted into feature vectors, the system returns the maximum-similarity items as recommendations to that user. Our experimental evaluation shows that our method of creating the user models and item feature-vectors resulted in higher precision and accuracy in comparison to well-known feature-vector-generating methods like Glove and Word2Vec. It also shows that stemming and the use of a modified version of tf-idf increase the accuracy and precision by 2% and 3%, respectively, compared to non-stemming and the standard tf-idf definition. Moreover, the evaluation results show that updating the user model from usage histories improves the precision and accuracy of the system. This recommender system has been developed as part of the Agnes application, which runs on iOS and Android platforms and is accessible through the Agnes website.

On the Alloying and Properties of Tetragonal Nb₅Si₃ in Nb-Silicide Based Alloys.

PubMed

Tsakiropoulos, Panos

2018-01-04

The alloying of Nb₅Si₃ modifies its properties. Actual compositions of (Nb,TM)₅X₃ silicides in developmental alloys, where X = Al + B + Ge + Si + Sn and TM is a transition and/or refractory metal, were used to calculate the composition weighted differences in electronegativity (Δχ) and an average valence electron concentration (VEC) and the solubility range of X to study the alloying and properties of the silicide. The calculations gave 4.11 < VEC < 4.45, 0.103 < Δχ < 0.415 and 33.6 < X < 41.6 at.%. In the silicide in Nb-24Ti-18Si-5Al-5Cr alloys with single addition of 5 at.% B, Ge, Hf, Mo, Sn and Ta, the solubility range of X decreased compared with the unalloyed Nb₅Si₃ or exceeded 40.5 at.% when B was with Hf or Mo or Sn and the Δχ decreased with increasing X. The Ge concentration increased with increasing Ti and the Hf concentration increased and decreased with increasing Ti or Nb respectively. The B and Sn concentrations respectively decreased and increased with increasing Ti and also depended on other additions in the silicide. The concentration of Sn was related to VEC and the concentrations of B and Ge were related to Δχ. The alloying of Nb₅Si₃ was demonstrated in Δχ versus VEC maps. Effects of alloying on the coefficient of thermal expansion (CTE) anisotropy, Young's modulus, hardness and creep data were discussed. Compared with the hardness of binary Nb₅Si₃ (1360 HV), the hardness increased in silicides with Ge and dropped below 1360 HV when Al, B and Sn were present without Ge. The Al effect on hardness depended on other elements substituting Si. Sn reduced the hardness. Ti or Hf reduced the hardness more than Cr in Nb₅Si₃ without Ge. The (Nb,Hf)₅(Si,Al)₃ had the lowest hardness. VEC differentiated the effects of additions on the hardness of Nb₅Si₃ alloyed with Ge. Deterioration of the creep of alloyed Nb₅Si₃ was accompanied by decrease of VEC and increase or decrease of Δχ depending on alloying addition(s).

FBST for Cointegration Problems

NASA Astrophysics Data System (ADS)

Diniz, M.; Pereira, C. A. B.; Stern, J. M.

2008-11-01

In order to estimate causal relations, the time series econometrics has to be aware of spurious correlation, a problem first mentioned by Yule [21]. To solve the problem, one can work with differenced series or use multivariate models like VAR or VEC models. In this case, the analysed series are going to present a long run relation i.e. a cointegration relation. Even though the Bayesian literature about inference on VAR/VEC models is quite advanced, Bauwens et al. [2] highlight that "the topic of selecting the cointegrating rank has not yet given very useful and convincing results." This paper presents the Full Bayesian Significance Test applied to cointegration rank selection tests in multivariate (VAR/VEC) time series models and shows how to implement it using available in the literature and simulated data sets. A standard non-informative prior is assumed.

Exact solutions to force-free electrodynamics in black hole backgrounds

NASA Astrophysics Data System (ADS)

Brennan, T. Daniel; Gralla, Samuel E.; Jacobson, Ted

2013-10-01

A shared property of several of the known exact solutions to the equations of force-free electrodynamics is that their charge-current four-vector is null. We examine the general properties of null-current solutions and then focus on the principal congruences of the Kerr black hole spacetime. We obtain a large class of exact solutions, which are in general time-dependent and non-axisymmetric. These solutions include waves that, surprisingly, propagate without scattering on the curvature of the black hole’s background. They may be understood as generalizations to Robinson’s solutions to vacuum electrodynamics associated with a shear-free congruence of null geodesics. When stationary and axisymmetric, our solutions reduce to those of Menon and Dermer, the only previously known solutions in Kerr. In Kerr, all of our solutions have null electromagnetic fields (\\vec{E} \\cdot \\vec{B} = 0 and E2 = B2). However, in Schwarzschild or flat spacetime there is freedom to add a magnetic monopole field, making the solutions magnetically dominated (B2 > E2). This freedom may be used to reproduce the various flat-spacetime and Schwarzschild-spacetime (split) monopole solutions available in the literature (due to Michel and later authors), and to obtain a large class of time-dependent, non-axisymmetric generalizations. These generalizations may be used to model the magnetosphere of a conducting star that rotates with arbitrary prescribed time-dependent rotation axis and speed. We thus significantly enlarge the class of known exact solutions, while organizing and unifying previously discovered solutions in terms of their null structure.

The Involvement of Lipid Peroxide-Derived Aldehydes in Aluminum Toxicity of Tobacco Roots1[W][OA

PubMed Central

Yin, Lina; Mano, Jun'ichi; Wang, Shiwen; Tsuji, Wataru; Tanaka, Kiyoshi

2010-01-01

Oxidative injury of the root elongation zone is a primary event in aluminum (Al) toxicity in plants, but the injuring species remain unidentified. We verified the hypothesis that lipid peroxide-derived aldehydes, especially highly electrophilic α,β-unsaturated aldehydes (2-alkenals), participate in Al toxicity. Transgenic tobacco (Nicotiana tabacum) overexpressing Arabidopsis (Arabidopsis thaliana) 2-alkenal reductase (AER-OE plants), wild-type SR1, and an empty vector-transformed control line (SR-Vec) were exposed to AlCl3 on their roots. Compared with the two controls, AER-OE plants suffered less retardation of root elongation under AlCl3 treatment and showed more rapid regrowth of roots upon Al removal. Under AlCl3 treatment, the roots of AER-OE plants accumulated Al and H2O2 to the same levels as did the sensitive controls, while they accumulated lower levels of aldehydes and suffered less cell death than SR1 and SR-Vec roots. In SR1 roots, AlCl3 treatment markedly increased the contents of the highly reactive 2-alkenals acrolein, 4-hydroxy-(E)-2-hexenal, and 4-hydroxy-(E)-2-nonenal and other aldehydes such as malondialdehyde and formaldehyde. In AER-OE roots, accumulation of these aldehydes was significantly less. Growth of the roots exposed to 4-hydroxy-(E)-2-nonenal and (E)-2-hexenal were retarded more in SR1 than in AER-OE plants. Thus, the lipid peroxide-derived aldehydes, formed downstream of reactive oxygen species, injured root cells directly. Their suppression by AER provides a new defense mechanism against Al toxicity. PMID:20023145

Virtual Evidence Cart - RP (VEC-RP).

PubMed

Liu, Fang; Fontelo, Paul; Muin, Michael; Ackerman, Michael

2005-01-01

VEC-RP (Virtual Evident Cart) is an open, Web-based, searchable collection of clinical questions and relevant references from MEDLINE/PubMed for healthcare professionals. The architecture consists of four parts: clinical questions, relevant articles from MEDLINE/PubMed, "bottom-line" answers, and peer reviews of entries. Only registered users can add reviews but unregistered users can read them. Feedback from physicians, mostly in the Philippines (RP) who tested the system, is positive.

Commensal Bacteria Modulate Innate Immune Responses of Vaginal Epithelial Cell Multilayer Cultures

PubMed Central

Rose, William A.; McGowin, Chris L.; Spagnuolo, Rae Ann; Eaves-Pyles, Tonyia D.; Popov, Vsevolod L.; Pyles, Richard B.

2012-01-01

The human vaginal microbiome plays a critical but poorly defined role in reproductive health. Vaginal microbiome alterations are associated with increased susceptibility to sexually-transmitted infections (STI) possibly due to related changes in innate defense responses from epithelial cells. Study of the impact of commensal bacteria on the vaginal mucosal surface has been hindered by current vaginal epithelial cell (VEC) culture systems that lack an appropriate interface between the apical surface of stratified squamous epithelium and the air-filled vaginal lumen. Therefore we developed a reproducible multilayer VEC culture system with an apical (luminal) air-interface that supported colonization with selected commensal bacteria. Multilayer VEC developed tight-junctions and other hallmarks of the vaginal mucosa including predictable proinflammatory cytokine secretion following TLR stimulation. Colonization of multilayers by common vaginal commensals including Lactobacillus crispatus, L. jensenii, and L. rhamnosus led to intimate associations with the VEC exclusively on the apical surface. Vaginal commensals did not trigger cytokine secretion but Staphylococcus epidermidis, a skin commensal, was inflammatory. Lactobacilli reduced cytokine secretion in an isolate-specific fashion following TLR stimulation. This tempering of inflammation offers a potential explanation for increased susceptibility to STI in the absence of common commensals and has implications for testing of potential STI preventatives. PMID:22412914

node2vec: Scalable Feature Learning for Networks

PubMed Central

Grover, Aditya; Leskovec, Jure

2016-01-01

Prediction tasks over nodes and edges in networks require careful effort in engineering features used by learning algorithms. Recent research in the broader field of representation learning has led to significant progress in automating prediction by learning the features themselves. However, present feature learning approaches are not expressive enough to capture the diversity of connectivity patterns observed in networks. Here we propose node2vec, an algorithmic framework for learning continuous feature representations for nodes in networks. In node2vec, we learn a mapping of nodes to a low-dimensional space of features that maximizes the likelihood of preserving network neighborhoods of nodes. We define a flexible notion of a node’s network neighborhood and design a biased random walk procedure, which efficiently explores diverse neighborhoods. Our algorithm generalizes prior work which is based on rigid notions of network neighborhoods, and we argue that the added flexibility in exploring neighborhoods is the key to learning richer representations. We demonstrate the efficacy of node2vec over existing state-of-the-art techniques on multi-label classification and link prediction in several real-world networks from diverse domains. Taken together, our work represents a new way for efficiently learning state-of-the-art task-independent representations in complex networks. PMID:27853626

Superrotation charge and supertranslation hair on black holes

DOE PAGES

Hawking, Stephen W.; Perry, Malcolm J.; Strominger, Andrew

2017-05-31

It is shown that black hole spacetimes in classical Einstein gravity are characterized by, in addition to their ADM mass M, momentummore » $$\\vec{P}$$, angular momentum $$\\vec{J}$$ and boost charge $$\\vec{/k}$$ , an infinite head of supertranslation hair. Furthermore, the distinct black holes are distinguished by classical superrotation charges measured at infinity. Solutions with supertranslation hair are diffeomorphic to the Schwarzschild spacetime, but the diffeomorphisms are part of the BMS subgroup and act nontrivially on the physical phase space. It is shown that a black hole can be supertranslated by throwing in an asymmetric shock wave. We derive a leading-order Bondi-gauge expression for the linearized horizon supertranslation charge and shown to generate, via the Dirac bracket, supertranslations on the linearized phase space of gravitational excitations of the horizon. The considerations of this paper are largely classical augmented by comments on their implications for the quantum theory.« less

Superrotation charge and supertranslation hair on black holes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hawking, Stephen W.; Perry, Malcolm J.; Strominger, Andrew

It is shown that black hole spacetimes in classical Einstein gravity are characterized by, in addition to their ADM mass M, momentummore » $$\\vec{P}$$, angular momentum $$\\vec{J}$$ and boost charge $$\\vec{/k}$$ , an infinite head of supertranslation hair. Furthermore, the distinct black holes are distinguished by classical superrotation charges measured at infinity. Solutions with supertranslation hair are diffeomorphic to the Schwarzschild spacetime, but the diffeomorphisms are part of the BMS subgroup and act nontrivially on the physical phase space. It is shown that a black hole can be supertranslated by throwing in an asymmetric shock wave. We derive a leading-order Bondi-gauge expression for the linearized horizon supertranslation charge and shown to generate, via the Dirac bracket, supertranslations on the linearized phase space of gravitational excitations of the horizon. The considerations of this paper are largely classical augmented by comments on their implications for the quantum theory.« less

On the Alloying and Properties of Tetragonal Nb5Si3 in Nb-Silicide Based Alloys

PubMed Central

Tsakiropoulos, Panos

2018-01-01

The alloying of Nb5Si3 modifies its properties. Actual compositions of (Nb,TM)5X3 silicides in developmental alloys, where X = Al + B + Ge + Si + Sn and TM is a transition and/or refractory metal, were used to calculate the composition weighted differences in electronegativity (Δχ) and an average valence electron concentration (VEC) and the solubility range of X to study the alloying and properties of the silicide. The calculations gave 4.11 < VEC < 4.45, 0.103 < Δχ < 0.415 and 33.6 < X < 41.6 at.%. In the silicide in Nb-24Ti-18Si-5Al-5Cr alloys with single addition of 5 at.% B, Ge, Hf, Mo, Sn and Ta, the solubility range of X decreased compared with the unalloyed Nb5Si3 or exceeded 40.5 at.% when B was with Hf or Mo or Sn and the Δχ decreased with increasing X. The Ge concentration increased with increasing Ti and the Hf concentration increased and decreased with increasing Ti or Nb respectively. The B and Sn concentrations respectively decreased and increased with increasing Ti and also depended on other additions in the silicide. The concentration of Sn was related to VEC and the concentrations of B and Ge were related to Δχ. The alloying of Nb5Si3 was demonstrated in Δχ versus VEC maps. Effects of alloying on the coefficient of thermal expansion (CTE) anisotropy, Young’s modulus, hardness and creep data were discussed. Compared with the hardness of binary Nb5Si3 (1360 HV), the hardness increased in silicides with Ge and dropped below 1360 HV when Al, B and Sn were present without Ge. The Al effect on hardness depended on other elements substituting Si. Sn reduced the hardness. Ti or Hf reduced the hardness more than Cr in Nb5Si3 without Ge. The (Nb,Hf)5(Si,Al)3 had the lowest hardness. VEC differentiated the effects of additions on the hardness of Nb5Si3 alloyed with Ge. Deterioration of the creep of alloyed Nb5Si3 was accompanied by decrease of VEC and increase or decrease of Δχ depending on alloying addition(s). PMID:29300327

Evolution of aerosol vertical distribution during particulate pollution events in Shanghai

NASA Astrophysics Data System (ADS)

Zhang, Yunwei; Zhang, Qun; Leng, Chunpeng; Zhang, Deqin; Cheng, Tiantao; Tao, Jun; Zhang, Renjian; He, Qianshan

2015-06-01

A set of micro pulse lidar (MPL) systems operating at 532 nm was used for ground-based observation of aerosols in Shanghai in 2011. Three typical particulate pollution events (e.g., haze) were examined to determine the evolution of aerosol vertical distribution and the planetary boundary layer (PBL) during these pollution episodes. The aerosol vertical extinction coefficient (VEC) at any given measured altitude was prominently larger during haze periods than that before or after the associated event. Aerosols originating from various source regions exerted forcing to some extent on aerosol loading and vertical layering, leading to different aerosol vertical distribution structures. Aerosol VECs were always maximized near the surface owing to the potential influence of local pollutant emissions. Several peaks in aerosol VECs were found at altitudes above 1 km during the dust- and bioburning-influenced haze events. Aerosol VECs decreased with increasing altitude during the local-polluted haze event, with a single maximum in the surface atmosphere. PM2.5 increased slowly while PBL and visibility decreased gradually in the early stages of haze events; subsequently, PM2.5 accumulated and was exacerbated until serious pollution bursts occurred in the middle and later stages. The results reveal that aerosols from different sources impact aerosol vertical distributions in the atmosphere and that the relationship between PBL and pollutant loadings may play an important role in the formation of pollution.

Sequence2Vec: a novel embedding approach for modeling transcription factor binding affinity landscape.

PubMed

Dai, Hanjun; Umarov, Ramzan; Kuwahara, Hiroyuki; Li, Yu; Song, Le; Gao, Xin

2017-11-15

An accurate characterization of transcription factor (TF)-DNA affinity landscape is crucial to a quantitative understanding of the molecular mechanisms underpinning endogenous gene regulation. While recent advances in biotechnology have brought the opportunity for building binding affinity prediction methods, the accurate characterization of TF-DNA binding affinity landscape still remains a challenging problem. Here we propose a novel sequence embedding approach for modeling the transcription factor binding affinity landscape. Our method represents DNA binding sequences as a hidden Markov model which captures both position specific information and long-range dependency in the sequence. A cornerstone of our method is a novel message passing-like embedding algorithm, called Sequence2Vec, which maps these hidden Markov models into a common nonlinear feature space and uses these embedded features to build a predictive model. Our method is a novel combination of the strength of probabilistic graphical models, feature space embedding and deep learning. We conducted comprehensive experiments on over 90 large-scale TF-DNA datasets which were measured by different high-throughput experimental technologies. Sequence2Vec outperforms alternative machine learning methods as well as the state-of-the-art binding affinity prediction methods. Our program is freely available at https://github.com/ramzan1990/sequence2vec. xin.gao@kaust.edu.sa or lsong@cc.gatech.edu. Supplementary data are available at Bioinformatics online. © The Author(s) 2017. Published by Oxford University Press.

Inhibitory effects of myricitrin on oxidative stress-induced endothelial damage and early atherosclerosis in ApoE −/− mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Gui-bo; Qin, Meng; Ye, Jing-xue

Atherosclerosis (AS) is a state of heightened oxidative stress characterized by lipid and protein oxidation in vascular walls. Oxidative stress-induced vascular endothelial cell (VEC) injury is a major factor in the pathogenesis of AS. Myricitrin, a natural flavonoid isolated from the root bark of Myrica cerifera, was recently found to have a strong antioxidative effect. However, its use for treating cardiovascular diseases, especially AS is still unreported. Consequently, we evaluated the cytoprotective effect of myricitrin on AS by assessing oxidative stress-induced VEC damage. The in vivo study using an ApoE −/− mouse model of AS demonstrated that myricitrin treatment protectsmore » against VEC damage and inhibits early AS plaque formation. This effect is associated with the antioxidative effect of myricitrin, as observed in a hydrogen peroxide (H{sub 2}O{sub 2})-induced rat model of artery endothelial injury and primary cultured human VECs. Myricitrin treatment also prevents and attenuates H{sub 2}O{sub 2}-induced endothelial injury. Further investigation of the cytoprotective effects of myricitrin demonstrated that myricitrin exerts its function by scavenging for reactive oxygen species, as well as reducing lipid peroxidation, blocking NO release, and maintaining mitochondrial transmembrane potential. Myricitrin treatment also significantly decreased H{sub 2}O{sub 2}-induced apoptosis in VECs, which was associated with significant inhibition of p53 gene expression, activation of caspase-3 and the MAPK signaling pathway, and alteration of the patterns of pro-apoptotic and anti-apoptotic gene expression. The resulting significantly increased bcl-2/bax ratio indicates that myricitrin may prevent the apoptosis induced by oxidative stress injury. - Highlights: • Myricitrin prevents early atherosclerosis in ApoE−/− mice. • Myricitrin protects endothelial cell from H{sub 2}O{sub 2} induced injury in rat and HUVECs. • Myricitrin enhanced NO release and up regulates eNOS activity in HUVECs. • Myricitrin down regulates P53 expression and MAPKs phosphorylation in HUVECs.« less

Measurement of the Neutron Electric Form Factor GEN at High Q2

NASA Astrophysics Data System (ADS)

McCormick, Kathy

2003-01-01

Experiment E02-0131 at Thomas Jefferson National Accelerator Facility (Jefferson Lab) will measure the neutron electric form factor GEn at the high four-momentum transfer values of Q2 ≈ 1.3, 2.4 and 3.4 (GeV/c)2 via a measurement of the cross section asymmetry AT in the reaction {}3vec He(vec e, e'n)pp . This measurement was approved for 32 days of running by Jefferson Lab PAC 212 in January 2002.

Quantitative investigations of xylose and arabinose substituents in hydroxypropylated and hydroxyvinylethylated arabinoxylans.

PubMed

Lorenz, Dominic; Knöpfle, Anna; Akil, Youssef; Saake, Bodo

2017-11-01

The chemical structures obtained by the modification of arabinoxylans with the cyclic carbonates propylene carbonate (PC) and 4-vinyl-1,3-dioxolan-2-one (VEC) with varying degrees of substitution were investigated. Therefore, a new analytical method was developed that is based on a microwave-assisted hydrolysis of the polysaccharides with trifluoroacetic acid and the reductive amination with 2-aminobenzoic acid. The peak assignment was achieved by HPLC-MS and the carbohydrate derivatives were quantified by HPLC-fluorescence. The obtained maximum molar substitution of PC-derivatized xylan (X HP ) was 1.8; the molar substitution of VEC-derivatized xylan (X HVE ) was 2.3. Investigations of xylose and arabinose based mono- and disubstituted derivatives revealed a preferred reaction of the cyclic carbonates with arabinose. Conversion rates were up to 2.4 times higher for monosubstitution and up to 3.0 times for disubstitution compared to xylose. Furthermore, the reaction with VEC was preferred due to higher reactivity of the newly introduced side chains. Copyright © 2017 Elsevier Ltd. All rights reserved.

Elemental maps in human allantochorial placental vessels cells: 1. High K + and acetylcholine effects

NASA Astrophysics Data System (ADS)

Michelet-Habchi, C.; Barberet, Ph.; Dutta, R. K.; Guiet-Bara, A.; Bara, M.; Moretto, Ph.

2003-09-01

Regulation of vascular tone in the fetal extracorporeal circulation most likely depends on circulating hormones, local paracrine mechanisms and changes in membrane potential of vascular smooth muscle cells (VSMCs) and of vascular endothelial cells (VECs). The membrane potential is a function of the physiological activities of ionic channels (particularly, K + and Ca 2+ channels in these cells). These channels regulate the ionic distribution into these cells. Micro-particle induced X-ray emission (PIXE) analysis was applied to determine the ionic composition of VSMC and of VEC in the placental human allantochorial vessels in a physiological survival medium (Hanks' solution) modified by the addition of acetylcholine (ACh: which opens the calcium-sensitive K + channels, K Ca) and of high concentration of K + (which blocks the voltage-sensitive K + channels, K df). In VSMC (media layer), the addition of ACh induced no modification of the Na, K, Cl, P, S, Mg and Ca concentrations and high K + medium increased significantly the Cl and K concentrations, the other ion concentrations remaining constant. In endothelium (VEC), ACh addition implicated a significant increase of Na and K concentration, and high K + medium, a significant increase in Cl and K concentration. These results indicated the importance of K df, K Ca and K ATP channels in the regulation of K + intracellular distribution in VSMC and VEC and the possible intervention of a Na-K-2Cl cotransport and corroborated the previous electrophysiological data.

Alloying and Hardness of Eutectics with Nbss and Nb5Si3 in Nb-silicide Based Alloys

PubMed Central

Tsakiropoulos, Panos

2018-01-01

In Nb-silicide based alloys, eutectics can form that contain the Nbss and Nb5Si3 phases. The Nb5Si3 can be rich or poor in Ti, the Nb can be substituted with other transition and refractory metals, and the Si can be substituted with simple metal and metalloid elements. For the production of directionally solidified in situ composites of multi-element Nb-silicide based alloys, data about eutectics with Nbss and Nb5Si3 is essential. In this paper, the alloying behaviour of eutectics observed in Nb-silicide based alloys was studied using the parameters ΔHmix, ΔSmix, VEC (valence electron concentration), δ (related to atomic size), Δχ (related to electronegativity), and Ω (= Tm ΔSmix/|ΔHmix|). The values of these parameters were in the ranges −41.9 < ΔHmix <−25.5 kJ/mol, 4.7 < ΔSmix < 15 J/molK, 4.33 < VEC < 4.89, 6.23 < δ < 9.44, 0.38 < Ω < 1.35, and 0.118 < Δχ < 0.248, with a gap in Δχ values between 0.164 and 0.181. Correlations between ΔSmix, Ω, ΔSmix, and VEC were found for all of the eutectics. The correlation between ΔHmix and δ for the eutectics was the same as that of the Nbss, with more negative ΔHmix for the former. The δ versus Δχ map separated the Ti-rich eutectics from the Ti-poor eutectics, with a gap in Δχ values between 0.164 and 0.181, which is within the Δχ gap of the Nbss. Eutectics were separated according to alloying additions in the Δχ versus VEC, Δχ versus , δ versus , and VEC versus maps, where = Al + Ge + Si + Sn. Convergence of data in maps occurred at δ ≈ 9.25, VEC ≈ 4.35, Δχ in the range ≈ 0.155 to 0.162, and in the range ≈ 21.6 at.% to ≈ 24.3 at.%. The convergence of data also indicated that the minimum concentration of Ti and maximum concentrations of Al and Si in the eutectic were about 8.7 at.% Ti, 6.3 at.% Al, and 21.6 at.% Si, respectively, and that the minimum concentration of Si in the eutectic was in the range 8 < Si < 10 at.%. PMID:29641503

Alloying and Hardness of Eutectics with Nbss and Nb₅Si₃ in Nb-silicide Based Alloys.

PubMed

Tsakiropoulos, Panos

2018-04-11

In Nb-silicide based alloys, eutectics can form that contain the Nb ss and Nb₅Si₃ phases. The Nb₅Si₃ can be rich or poor in Ti, the Nb can be substituted with other transition and refractory metals, and the Si can be substituted with simple metal and metalloid elements. For the production of directionally solidified in situ composites of multi-element Nb-silicide based alloys, data about eutectics with Nb ss and Nb₅Si₃ is essential. In this paper, the alloying behaviour of eutectics observed in Nb-silicide based alloys was studied using the parameters ΔH mix , ΔS mix , VEC (valence electron concentration), δ (related to atomic size), Δχ (related to electronegativity), and Ω (= T m ΔS mix /|ΔH mix |). The values of these parameters were in the ranges -41.9 < ΔH mix <-25.5 kJ/mol, 4.7 < ΔS mix < 15 J/molK, 4.33 < VEC < 4.89, 6.23 < δ < 9.44, 0.38 < Ω < 1.35, and 0.118 < Δχ < 0.248, with a gap in Δχ values between 0.164 and 0.181. Correlations between ΔS mix , Ω, ΔS mix , and VEC were found for all of the eutectics. The correlation between ΔH mix and δ for the eutectics was the same as that of the Nb ss , with more negative ΔH mix for the former. The δ versus Δχ map separated the Ti-rich eutectics from the Ti-poor eutectics, with a gap in Δχ values between 0.164 and 0.181, which is within the Δχ gap of the Nb ss . Eutectics were separated according to alloying additions in the Δχ versus VEC, Δχ versus , δ versus , and VEC versus maps, where = Al + Ge + Si + Sn. Convergence of data in maps occurred at δ ≈ 9.25, VEC ≈ 4.35, Δχ in the range ≈ 0.155 to 0.162, and in the range ≈ 21.6 at.% to ≈ 24.3 at.%. The convergence of data also indicated that the minimum concentration of Ti and maximum concentrations of Al and Si in the eutectic were about 8.7 at.% Ti, 6.3 at.% Al, and 21.6 at.% Si, respectively, and that the minimum concentration of Si in the eutectic was in the range 8 < Si < 10 at.%.

Increased EGFR expression induced by a novel oncogene, CUG2, confers resistance to doxorubicin through Stat1-HDAC4 signaling.

PubMed

Kaowinn, Sirichat; Jun, Seung Won; Kim, Chang Seok; Shin, Dong-Myeong; Hwang, Yoon-Hwae; Kim, Kyujung; Shin, Bosung; Kaewpiboon, Chutima; Jeong, Hyeon Hee; Koh, Sang Seok; Krämer, Oliver H; Johnston, Randal N; Chung, Young-Hwa

2017-12-01

Previously, it has been found that the cancer upregulated gene 2 (CUG2) and the epidermal growth factor receptor (EGFR) both contribute to drug resistance of cancer cells. Here, we explored whether CUG2 may exert its anticancer drug resistance by increasing the expression of EGFR. EGFR expression was assessed using Western blotting, immunofluorescence and capacitance assays in A549 lung cancer and immortalized bronchial BEAS-2B cells, respectively, stably transfected with a CUG2 expression vector (A549-CUG2; BEAS-CUG2) or an empty control vector (A549-Vec; BEAS-Vec). After siRNA-mediated EGFR, Stat1 and HDAC4 silencing, antioxidant and multidrug resistance protein and mRNA levels were assessed using Western blotting and RT-PCR. In addition, the respective cells were treated with doxorubicin after which apoptosis and reactive oxygen species (ROS) levels were measured. Stat1 acetylation was assessed by immunoprecipitation. We found that exogenous CUG2 overexpression induced EGFR upregulation in A549 and BEAS-2B cells, whereas EGFR silencing sensitized these cells to doxorubicin-induced apoptosis. In addition, we found that exogenous CUG2 overexpression reduced the formation of ROS during doxorubicin treatment by enhancing the expression of antioxidant and multidrug resistant proteins such as MnSOD, Foxo1, Foxo4, MRP2 and BCRP, whereas EGFR silencing congruently increased the levels of ROS by decreasing the expression of these proteins. We also found that EGFR silencing and its concomitant Akt, ERK, JNK and p38 MAPK inhibition resulted in a decreased Stat1 phosphorylation and, thus, a decreased activation. Since also acetylation can affect Stat1 activation via a phospho-acetyl switch, HDAC inhibition may sensitize cells to doxorubicin-induced apoptosis. Interestingly, we found that exogenous CUG2 overexpression upregulated HDAC4, but not HDAC2 or HDAC3. Conversely, we found that HDAC4 silencing sensitized the cells to doxorubicin resistance by decreasing Stat1 phosphorylation and EGFR expression, thus indicating an interplay between HDAC4, Stat1 and EGFR. Taken together, we conclude that CUG2-induced EGFR upregulation confers doxorubicin resistance to lung (cancer) cells through Stat1-HDAC4 signaling.

Efficient Parallel Formulations of Hierarchical Methods and Their Applications

NASA Astrophysics Data System (ADS)

Grama, Ananth Y.

1996-01-01

Hierarchical methods such as the Fast Multipole Method (FMM) and Barnes-Hut (BH) are used for rapid evaluation of potential (gravitational, electrostatic) fields in particle systems. They are also used for solving integral equations using boundary element methods. The linear systems arising from these methods are dense and are solved iteratively. Hierarchical methods reduce the complexity of the core matrix-vector product from O(n^2) to O(n log n) and the memory requirement from O(n^2) to O(n). We have developed highly scalable parallel formulations of a hybrid FMM/BH method that are capable of handling arbitrarily irregular distributions. We apply these formulations to astrophysical simulations of Plummer and Gaussian galaxies. We have used our parallel formulations to solve the integral form of the Laplace equation. We show that our parallel hierarchical mat-vecs yield high efficiency and overall performance even on relatively small problems. A problem containing approximately 200K nodes takes under a second to compute on 256 processors and yet yields over 85% efficiency. The efficiency and raw performance is expected to increase for bigger problems. For the 200K node problem, our code delivers about 5 GFLOPS of performance on a 256 processor T3D. This is impressive considering the fact that the problem has floating point divides and roots, and very little locality resulting in poor cache performance. A dense matrix-vector product of the same dimensions would require about 0.5 TeraBytes of memory and about 770 TeraFLOPS of computing speed. Clearly, if the loss in accuracy resulting from the use of hierarchical methods is acceptable, our code yields significant savings in time and memory. We also study the convergence of a GMRES solver built around this mat-vec. We accelerate the convergence of the solver using three preconditioning techniques: diagonal scaling, block-diagonal preconditioning, and inner-outer preconditioning. We study the performance and parallel efficiency of these preconditioned solvers. Using this solver, we solve dense linear systems with hundreds of thousands of unknowns. Solving a 105K unknown problem takes about 10 minutes on a 64 processor T3D. Until very recently, boundary element problems of this magnitude could not even be generated, let alone solved.

Semantic relatedness and similarity of biomedical terms: examining the effects of recency, size, and section of biomedical publications on the performance of word2vec.

PubMed

Zhu, Yongjun; Yan, Erjia; Wang, Fei

2017-07-03

Understanding semantic relatedness and similarity between biomedical terms has a great impact on a variety of applications such as biomedical information retrieval, information extraction, and recommender systems. The objective of this study is to examine word2vec's ability in deriving semantic relatedness and similarity between biomedical terms from large publication data. Specifically, we focus on the effects of recency, size, and section of biomedical publication data on the performance of word2vec. We download abstracts of 18,777,129 articles from PubMed and 766,326 full-text articles from PubMed Central (PMC). The datasets are preprocessed and grouped into subsets by recency, size, and section. Word2vec models are trained on these subtests. Cosine similarities between biomedical terms obtained from the word2vec models are compared against reference standards. Performance of models trained on different subsets are compared to examine recency, size, and section effects. Models trained on recent datasets did not boost the performance. Models trained on larger datasets identified more pairs of biomedical terms than models trained on smaller datasets in relatedness task (from 368 at the 10% level to 494 at the 100% level) and similarity task (from 374 at the 10% level to 491 at the 100% level). The model trained on abstracts produced results that have higher correlations with the reference standards than the one trained on article bodies (i.e., 0.65 vs. 0.62 in the similarity task and 0.66 vs. 0.59 in the relatedness task). However, the latter identified more pairs of biomedical terms than the former (i.e., 344 vs. 498 in the similarity task and 339 vs. 503 in the relatedness task). Increasing the size of dataset does not always enhance the performance. Increasing the size of datasets can result in the identification of more relations of biomedical terms even though it does not guarantee better precision. As summaries of research articles, compared with article bodies, abstracts excel in accuracy but lose in coverage of identifiable relations.

Naringin inhibits vascular endothelial cell apoptosis via endoplasmic reticulum stress- and mitochondrial-mediated pathways and promotes intraosseous angiogenesis in ovariectomized rats

PubMed Central

Li, Zhan-Chun; Tang, Lu-Min; Shao, Jiang; Li, He

2017-01-01

In this study, to investigate the effects of naringin on vascular endothelial cell (VEC) function, proliferation, apoptosis, and angiogenesis, rat VECs were cultured in vitro and randomly divided into four groups: control, serum-starved, low-concentration naringin treatment, and high-concentration naringin treatment. MTT assay was used to detect cell proliferation while Hoechst 33258 staining and flow cytometry were used to detect apoptosis. Changes in the expression of apoptosis-associated proteins [GRP78, CHOP, caspase-12, and cytochrome c (Cyt.c)] were detected using western blotting. JC-1 staining was employed to detect changes in mitochondrial membrane potential. Intracellular caspase-3, -8, and -9 activity was determined by spectrophotometry. ELISA was used to detect endothelin (ET), and a Griess assay was used to detect changes in the expression of nitric oxide (NO) in culture medium. The study further divided an ovariectomized (OVX) rat model of osteoporosis randomly into four groups: OVX, sham-operated, low-concentration naringin treatment (100 mg/kg), and high-concentration naringin treatment (200 mg/kg). After 3 months of treatment, changes in serum ET and NO expression, bone mineral density (BMD), and microvessel density of the distal femur (using CD34 labeling of VECs) were determined. At each concentration, naringin promoted VEC proliferation in a time- and dose-dependent manner. Naringin also significantly reduced serum starvation-induced apoptosis in endothelial cells, inhibited the expression of GRP78, CHOP, caspase-12, and Cyt.c proteins, and reduced mitochondrial membrane potential as well as reduced the activities of caspase-3 and -9. Furthermore, naringin suppressed ET in vitro and in vivo while enhancing NO synthesis. Distal femoral microvascular density assessment showed that the naringin treatment groups had a significantly higher number of microvessels than the OVX group, and that microvascular density was positively correlated with BMD. In summary, naringin inhibits apoptosis in VECs by blocking the endoplasmic reticulum (ER) stress- and mitochondrial-mediated pathways. Naringin also regulates endothelial cell function and promotes angiogenesis to exert its anti-osteoporotic effect. PMID:29039439

Naringin inhibits vascular endothelial cell apoptosis via endoplasmic reticulum stress‑ and mitochondrial‑mediated pathways and promotes intraosseous angiogenesis in ovariectomized rats.

PubMed

Shangguan, Wen-Ji; Zhang, Yue-Hui; Li, Zhan-Chun; Tang, Lu-Min; Shao, Jiang; Li, He

2017-12-01

In this study, to investigate the effects of naringin on vascular endothelial cell (VEC) function, proliferation, apoptosis, and angiogenesis, rat VECs were cultured in vitro and randomly divided into four groups: control, serum‑starved, low‑concentration naringin treatment, and high‑concentration naringin treatment. MTT assay was used to detect cell proliferation while Hoechst 33258 staining and flow cytometry were used to detect apoptosis. Changes in the expression of apoptosis‑associated proteins [GRP78, CHOP, caspase‑12, and cytochrome c (Cyt.c)] were detected using western blotting. JC‑1 staining was employed to detect changes in mitochondrial membrane potential. Intracellular caspase‑3, ‑8, and ‑9 activity was determined by spectrophotometry. ELISA was used to detect endothelin (ET), and a Griess assay was used to detect changes in the expression of nitric oxide (NO) in culture medium. The study further divided an ovariectomized (OVX) rat model of osteoporosis randomly into four groups: OVX, sham‑operated, low‑concentration naringin treatment (100 mg/kg), and high‑concentration naringin treatment (200 mg/kg). After 3 months of treatment, changes in serum ET and NO expression, bone mineral density (BMD), and microvessel density of the distal femur (using CD34 labeling of VECs) were determined. At each concentration, naringin promoted VEC proliferation in a time‑ and dose‑dependent manner. Naringin also significantly reduced serum starvation‑induced apoptosis in endothelial cells, inhibited the expression of GRP78, CHOP, caspase‑12, and Cyt.c proteins, and reduced mitochondrial membrane potential as well as reduced the activities of caspase‑3 and ‑9. Furthermore, naringin suppressed ET in vitro and in vivo while enhancing NO synthesis. Distal femoral microvascular density assessment showed that the naringin treatment groups had a significantly higher number of microvessels than the OVX group, and that microvascular density was positively correlated with BMD. In summary, naringin inhibits apoptosis in VECs by blocking the endoplasmic reticulum (ER) stress‑ and mitochondrial‑mediated pathways. Naringin also regulates endothelial cell function and promotes angiogenesis to exert its anti‑osteoporotic effect.

A butyrolactone derivative suppressed lipopolysaccharide-induced autophagic injury through inhibiting the autoregulatory loop of p8 and p53 in vascular endothelial cells.

PubMed

Meng, Ning; Zhao, Jing; Su, Le; Zhao, Baoxiang; Zhang, Yun; Zhang, Shangli; Miao, Junying

2012-02-01

Lipopolysaccharide (LPS)-induced vascular endothelial cell (VEC) dysfunction is an important contributing factor in vascular diseases. Recently, we found that LPS impaired VEC by inducing autophagy. Our previous researches showed that a butyrolactone derivative, 3-benzyl-5-((2-nitrophenoxy) methyl)-dihydrofuran-2(3H)-one (3BDO) selectively protected VEC function. The objective of the present study is to investigate whether and how 3BDO inhibits LPS-induced VEC autophagic injury. Our results showed that LPS induced autophagy and led to increase of reactive oxygen species (ROS) and decrease of mitochondrial membrane potential (MMP) in Human umbilical vein vascular endothelial cells (HUVECs). Furthermore, LPS significantly increased p8 and p53 protein levels and the nuclear translocation of p53. All of these effects of LPS on HUVECs were strongly inhibited by 3BDO. Importantly, the ROS scavenger N-acetylcysteine (NAC) could inhibited LPS-induced autophagy and knockdown of p8 by RNA interference inhibited the autophagy, p53 protein level increase, the translocation of p53 into nuclei and the ROS level increase induced by LPS in HUVECs. The data suggested that 3BDO inhibited LPS-induced autophagy in HUVECs through inhibiting the ROS overproduction, the increase of p8 and p53 expression and the nuclear translocation of p53. Our findings provide a potential tool for understanding the mechanism underlying LPS-induced autophagy in HUVECs and open the door to a novel therapeutic drug for LPS-induced vascular diseases. Copyright © 2011 Elsevier Ltd. All rights reserved.

Nailfold capillary morphological characteristics of hand-arm vibration syndrome: a cross-sectional study

PubMed Central

Chen, QingSong; Chen, GuiPing; Xiao, Bin; Lin, HanSheng; Qu, HongYing; Zhang, DanYing; Shi, MaoGong; Lang, Li; Yang, Bei; Yan, MaoSheng

2016-01-01

Objective The purpose of this study was to investigate the characteristics of nailfold capillaroscopy associated with hand-arm vibration syndrome (HAVS). Methods In total, 113 male gold miners were recruited: 35 workers who were chronically exposed to vibration and developed vibration-induced white finger were defined as the HAVS group, 39 workers who were exposed to vibration but did not have HAVS were classified as the vibration-exposed controls (VEC) group, and 39 workers without vibration exposure were categorised as the non-VEC (NVEC) group. Video capillaroscopy was used to capture images of the 2nd, 3rd and 4th fingers of both hands. The following nailfold capillary characteristics were included: number of capillaries/mm, avascular areas, haemorrhages and enlarged capillaries. The experiments were carried out in the same winter. All characteristics were evaluated under blinded conditions. Results Significant differences in all morphological characteristics existed between the groups (p<0.05). Avascular areas in the HAVS, VEC and NVEC groups appeared in 74.3%, 43.6% and 25.0% of participants, respectively. A higher percentage of participants had haemorrhages in the HAVS group (65.7%) compared with the other groups (VEC: 7.7% and NVEC: 7.5%). The number of capillaries/mm, input limb width, output limb width, apical width, and ratio of output limb and input limb all had more than 70% sensitivity or specificity of their cut-off value. Conclusions Nailfold capillary characteristics, especially the number of capillaries/mm, avascular areas, haemorrhages, output limb width, input limb width and apical width alterations, revealed significant associations with HAVS. PMID:27888176

Margined winner-take-all: New learning rule for pattern recognition.

PubMed

Fukushima, Kunihiko

2018-01-01

The neocognitron is a deep (multi-layered) convolutional neural network that can be trained to recognize visual patterns robustly. In the intermediate layers of the neocognitron, local features are extracted from input patterns. In the deepest layer, based on the features extracted in the intermediate layers, input patterns are classified into classes. A method called IntVec (interpolating-vector) is used for this purpose. This paper proposes a new learning rule called margined Winner-Take-All (mWTA) for training the deepest layer. Every time when a training pattern is presented during the learning, if the result of recognition by WTA (Winner-Take-All) is an error, a new cell is generated in the deepest layer. Here we put a certain amount of margin to the WTA. In other words, only during the learning, a certain amount of handicap is given to cells of classes other than that of the training vector, and the winner is chosen under this handicap. By introducing the margin to the WTA, we can generate a compact set of cells, with which a high recognition rate can be obtained with a small computational cost. The ability of this mWTA is demonstrated by computer simulation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Polarization observables in deuteron photodisintegration below 360 MeV

DOE PAGES

Glister, J.; Ron, G.; Lee, B. W.; ...

2011-02-03

We performed high precision measurements of induced and transferred recoil proton polarization in d(more » $$\\vec{γ}$$, $$\\vec{p}$$)n for photon energies of 277--357 MeV and θ cm = 20 ° -- 120 °. The measurements were motivated by a longstanding discrepancy between meson-baryon model calculations and data at higher energies. Moreover, at the low energies of this experiment, theory continues to fail to reproduce the data, indicating that either something is missing in the calculations and/or there is a problem with the accuracy of the nucleon-nucleon potential being used.« less

Plasma microRNAs levels are different between pulmonary and extrapulmonary ARDS patients: a clinical observational study.

PubMed

Zheng, Yi; Liu, Song-Qiao; Sun, Qin; Xie, Jian-Feng; Xu, Jing-Yuan; Li, Qing; Pan, Chun; Liu, Ling; Huang, Ying-Zi

2018-02-13

Mesenchymal stem cells (MSC) obviously alleviate the damage of the structure and function of pulmonary vascular endothelial cells (VEC). The therapeutic effects of MSC are significantly different between pulmonary ARDS (ARDSp) and extrapulmonary ARDS (ARDSexp). MicroRNAs (miRNAs), as important media of MSC regulating VEC, are not studied between ARDSp and ARDSexp. We aimed to explore the plasma levels difference of miRNAs that regulate VEC function and are associated with MSC (MSC-VEC-miRNAs) between ARDSp and ARDSexp patients. MSC-VEC-miRNAs were obtained through reviewing relevant literatures screened in PubMed database. We enrolled 57 ARDS patients within 24 h of admission to the ICU and then collected blood samples, extracted plasma supernatant. Patients' clinical data were collected. Then, plasma expression of MSC-VEC-miRNAs was measured by real-time fluorescence quantitative PCR. Simultaneously, plasma endothelial injury markers VCAM-1, vWF and inflammatory factors TNF-α, IL-10 were detected by ELISA method. Fourteen miRNAs were picked out after screening. A total of 57 ARDS patients were included in this study, among which 43 cases pertained to ARDSp group and 14 cases pertained to ARDSexp group. Plasma miR-221 and miR-27b levels in ARDSexp group exhibited significantly lower than that in ARDSp group (miR-221, 0.22 [0.12-0.49] vs. 0.57 [0.22-1.57], P = 0.008, miR-27b, 0.34 [0.10-0.46] vs. 0.60 [0.20-1.46], P = 0.025). Plasma vWF concentration in ARDSexp group exhibited significantly lower than that in ARDSp group (0.77 [0.29-1.54] vs. 1.80 [0.95-3.51], P = 0.048). Significant positive correlation was found between miR-221 and vWF in plasma levels (r = 0.688, P = 0.022). Plasma miR-26a and miR-27a levels in non-survival group exhibited significantly lower than that in survival group (miR-26a, 0.17 [0.08-0.20] vs. 0.69 [0.24-2.33] P = 0.018, miR-27a, 0.23 [0.16-0.58] vs. 1.45 [0.38-3.63], P = 0.021) in ARDSp patients. Plasma miR-221, miR-27b and vWF levels in ARDSexp group are significantly lower than that in ARDSp group. Plasma miR-26a and miR-27a levels in non-survival group are significantly lower than that in survival group in ARDSp patients.

Dynamic modeling for flow-activated chloride-selective membrane current in vascular endothelial cells.

PubMed

Qin, Kai-Rong; Xiang, Cheng; Cao, Ling-Ling

2011-10-01

In this paper, a dynamic model is proposed to quantify the relationship between fluid flow and Cl(-)-selective membrane current in vascular endothelial cells (VECs). It is assumed that the external shear stress would first induce channel deformation in VECs. This deformation could activate the Cl(-) channels on the membrane, thus allowing Cl(-) transport across the membrane. A modified Hodgkin-Huxley model is embedded into our dynamic system to describe the electrophysiological properties of the membrane, such as the Cl(-)-selective membrane current (I), voltage (V) and conductance. Three flow patterns, i. e., steady flow, oscillatory flow, and pulsatile flow, are applied in our simulation studies. When the extracellular Cl(-) concentration is constant, the I-V characteristics predicted by our dynamic model shows strong consistency with the experimental observations. It is also interesting to note that the Cl(-) currents under different flow patterns show some differences, indicating that VECs distinguish among and respond differently to different types of flows. When the extracellular Cl(-) concentration keeps constant or varies slowly with time (i.e. oscillates at 0.02 Hz), the convection and diffusion of Cl(-) in extracellular space can be ignored and the Cl(-) current is well captured by the modified Hodgkin-Huxley model alone. However, when the extracellular Cl(-) varies fast (i.e., oscillates at 0.2 Hz), the convection and diffusion effect should be considered because the Cl(-) current dynamics is different from the case where the convection-diffusion effect is simply ignored. The proposed dynamic model along with the simulation results could not only provide more insights into the flow-regulated electrophysiological behavior of the cell membrane but also help to reveal new findings in the electrophysiological experimental investigations of VECs in response to dynamic flow and biochemical stimuli.

Nailfold capillary morphological characteristics of hand-arm vibration syndrome: a cross-sectional study.

PubMed

Chen, QingSong; Chen, GuiPing; Xiao, Bin; Lin, HanSheng; Qu, HongYing; Zhang, DanYing; Shi, MaoGong; Lang, Li; Yang, Bei; Yan, MaoSheng

2016-11-25

The purpose of this study was to investigate the characteristics of nailfold capillaroscopy associated with hand-arm vibration syndrome (HAVS). In total, 113 male gold miners were recruited: 35 workers who were chronically exposed to vibration and developed vibration-induced white finger were defined as the HAVS group, 39 workers who were exposed to vibration but did not have HAVS were classified as the vibration-exposed controls (VEC) group, and 39 workers without vibration exposure were categorised as the non-VEC (NVEC) group. Video capillaroscopy was used to capture images of the 2nd, 3rd and 4th fingers of both hands. The following nailfold capillary characteristics were included: number of capillaries/mm, avascular areas, haemorrhages and enlarged capillaries. The experiments were carried out in the same winter. All characteristics were evaluated under blinded conditions. Significant differences in all morphological characteristics existed between the groups (p<0.05). Avascular areas in the HAVS, VEC and NVEC groups appeared in 74.3%, 43.6% and 25.0% of participants, respectively. A higher percentage of participants had haemorrhages in the HAVS group (65.7%) compared with the other groups (VEC: 7.7% and NVEC: 7.5%). The number of capillaries/mm, input limb width, output limb width, apical width, and ratio of output limb and input limb all had more than 70% sensitivity or specificity of their cut-off value. Nailfold capillary characteristics, especially the number of capillaries/mm, avascular areas, haemorrhages, output limb width, input limb width and apical width alterations, revealed significant associations with HAVS. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Regulation of Plasminogen Activation on Cell Surfaces and Fibrin.

PubMed

Urano, Tetsumei; Castellino, Francis J; Suzuki, Yuko

2018-05-20

The fibrinolytic system dissolves fibrin and maintains vascular patency. Recent advances in imaging analyses allowed visualization of the spatiotemporal regulatory mechanism of fibrinolysis, as well as its regulation by other plasma haemostasis cofactors. Vascular endothelial cells (VECs) retain tissue-type plasminogen activator (tPA) after secretion and maintain high plasminogen (plg) activation potential on their surfaces. As in plasma, the serpin, plasminogen activator inhibitor type 1 (PAI-1), regulates fibrinolytic potential via inhibition of the VEC surface-bound plg activator, tPA. Once fibrin is formed, plg activation by tPA is initiated and effectively amplified on the surface of fibrin, and fibrin is rapidly degraded. The specific binding of plg and tPA to lytic edges of partly degraded fibrin via newly generated C-terminal lysine residues, which amplifies fibrin digestion, is a central aspect of this pathophysiological mechanism. Thrombomodulin (TM) plays a role in the attenuation of the plg binding on fibrin and the associated fibrinolysis, which is reversed by a carboxypeptidase B inhibitor. This suggests that the plasma procarboxypeptidase B, thrombin activatable fibrinolysis inhibitor (TAFI), which is activated by thrombin bound to TM on VECs, is a critical aspect of the regulation of plg activation on VECs and subsequent fibrinolysis. Platelets also contain PAI-1, TAFI, TM and the fibrin crosslinking enzyme, Factor (F) XIIIa, and either secrete or expose these agents upon activation in order to regulate fibrinolysis. In this review, the native machinery of plg activation and fibrinolysis, as well as their spatiotemporal regulatory mechanisms, as revealed by imaging analyses, are discussed. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Nonlinear optical properties of rhenium(I) complexes: Influence of the extended π-conjugated connectors and proton abstraction.

PubMed

Yu, Hai-Ling; Hong, Bo; Yang, Ning; Zhao, Hong-Yan

2015-09-01

The photoinduced proton-coupled electron transfer chemistry is very crucial to the development of nonlinear optical (NLO) materials with large first hyperpolarizability contrast. We have performed a systematic investigation on the geometric structures, NLO switching, and simulated absorption spectra of rhenium(I) complexes via density functional theory (DFT). The results show that the first hyperpolarizabilities (βvec) increase remarkably with further extending of the organic connectors. In addition, the solvent leads to a slight enhancement of the hyperpolarizability and frequency dependent hyperpolarizability. Furthermore, the proton abstraction plays an important role in tuning the second-order NLO response. It is found that deprotonation not only increases the absolute value of βvec but also changes the sign of βvec from positive to negative. This different sign can be explained by the opposite dipole moments. The efficient enhancement of first hyperpolarizability is attributed to the better delocalization of the π-electron system and the more obvious degree of charge transfer. Therefore, these kinds of complexes might be promising candidates for designed as proton driven molecular second-order NLO switching. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of protein tyrosine phosphatase-PEST are reversed by Akt in T cells.

PubMed

Arimura, Yutaka; Shimizu, Kazuhiko; Koyanagi, Madoka; Yagi, Junji

2014-12-01

T cell activation is regulated by a balance between phosphorylation and dephosphorylation that is under the control of kinases and phosphatases. Here, we examined the role of a non-receptor-type protein tyrosine phosphatase, PTP-PEST, using retrovirus-mediated gene transduction into murine T cells. Based on observations of vector markers (GFP or Thy1.1), exogenous PTP-PEST-positive CD4(+) T cells appeared within 2 days after gene transduction; the percentage of PTP-PEST-positive cells tended to decrease during a resting period in the presence of IL-2 over the next 2 days. These vector markers also showed much lower expression intensities, compared with control cells, suggesting a correlation between the percent reduction and the low marker expression intensity. A catalytically inactive PTP-PEST mutant also showed the same tendency, and stepwise deletion mutants gradually lost their ability to induce the above phenomenon. On the other hand, these PTP-PEST-transduced cells did not have an apoptotic phenotype. No difference in the total cell numbers was found in the wells of a culture plate containing VEC- and PTP-PEST-transduced T cells. Moreover, serine/threonine kinase Akt, but not the anti-apoptotic molecules Bcl-2 and Bcl-XL, reversed the phenotype induced by PTP-PEST. We discuss the novel mechanism by which Akt interferes with PTP-PEST. Copyright © 2014 Elsevier Inc. All rights reserved.

Plasma detachment in divertor tokamaks

DOE PAGES

Leonard, A. W.

2018-02-07

In this study, observations of divertor plasma detachment in tokamaks are reviewed. Plasma detachment is characterized in terms of transport and dissipation of power, momentum and particle flux along the open field lines from the midplane to the divertor. Asymmetries in detachment onset and other characteristics between the inboard and outboard divertor plasmas is found to be primarily driven by plasmamore » $$\\vec{E}$$ x $$\\vec{B}$$ drifts. The effect of divertor plate geometry and magnetic configuration on divertor detachment is summarized. Control of divertor detachment has progressed with a development of a number of diagnostics to characterize the detached state in real-time. Finally the compatibility of detached divertor operation with high performance core plasmas is examined.« less

Plasma detachment in divertor tokamaks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leonard, A. W.

In this study, observations of divertor plasma detachment in tokamaks are reviewed. Plasma detachment is characterized in terms of transport and dissipation of power, momentum and particle flux along the open field lines from the midplane to the divertor. Asymmetries in detachment onset and other characteristics between the inboard and outboard divertor plasmas is found to be primarily driven by plasmamore » $$\\vec{E}$$ x $$\\vec{B}$$ drifts. The effect of divertor plate geometry and magnetic configuration on divertor detachment is summarized. Control of divertor detachment has progressed with a development of a number of diagnostics to characterize the detached state in real-time. Finally the compatibility of detached divertor operation with high performance core plasmas is examined.« less

An evaluation of the environmental and health effects of vehicle exhaust catalysts in the UK.

PubMed Central

Hutchinson, Emma J; Pearson, Peter J G

2004-01-01

Since 1993, all new gasoline-engine automobiles in the United Kingdom have been supplied with three-way vehicle exhaust catalytic converters (VECs) containing platinum, palladium, and rhodium, to comply with European Commission Stage I limits on emissions of regulated pollutants: carbon monoxide, hydrocarbons, and oxides of nitrogen. We conducted a physical and economic evaluation of the environmental and health benefits from a reduction in emissions through this mandated environmental technology against the costs, with reference to urban areas in Great Britain. We made both an ex post assessment--based on available data to 1998--and an ex ante assessment--projected to 2005, the year when full penetration of VECs into the fleet is expected. Substantial health benefits in excess of the costs of VECs were indicated: By 1998 the estimated net societal health benefits were approximately 500 million British pounds, and by 2005 they were estimated to rise to as much as 2 billion British pounds. We also found through environmental surveys that although lead in road dust has fallen by 50% in urban areas, platinum accumulations near roads have risen significantly, up to 90-fold higher than natural background levels. This rapid accumulation of platinum suggests further monitoring is warranted, although as yet there is no evidence of adverse health effects. PMID:14754566

In vitro activity of farnesol against vaginal Lactobacillus spp.

PubMed

Wang, Fengjuan; Liu, Zhaohui; Zhang, Dai; Niu, Xiaoxi

2017-05-01

Farnesol, a quorum-sensing molecule in Candida albicans, can affect the growth of certain microorganisms. The objective of this study was to evaluate the in vitro activity of farnesol against vaginal Lactobacillus spp., which play a crucial role in the maintenance of vaginal health. Growth and metabolic viability of vaginal Lactobacillus spp. incubated with different concentrations of farnesol were determined by measuring the optical density of the cultures and with the MTT assay. Morphology of the farnesol-treated cells was evaluated using a scanning electron microscope. In vitro adherence of vaginal Lactobacillus cells treated with farnesol was determined by co-incubating with vaginal epithelial cells (VECs). The minimum inhibitory concentration (MIC) of farnesol for vaginal Lactobacillus spp. was 1500μM. No morphological changes were observed when the farnesol-treated Lactobacillus cells were compared with farnesol-free cells, and 100μM farnesol would reduce the adherence of vaginal Lactobacillus to VECs. Farnesol acted as a potential antimicrobial agent, had little impact on the growth, metabolism, and cytomorphology of the vaginal Lactobacillus spp.; however, it affected their adhering capacity to VECs. The safety of farnesol as an adjuvant for antimicrobial agents during the treatment of vaginitis needs to be studied further. Copyright © 2017 Elsevier B.V. All rights reserved.

An evaluation of the environmental and health effects of vehicle exhaust catalysts in the UK.

PubMed

Hutchinson, Emma J; Pearson, Peter J G

2004-02-01

Since 1993, all new gasoline-engine automobiles in the United Kingdom have been supplied with three-way vehicle exhaust catalytic converters (VECs) containing platinum, palladium, and rhodium, to comply with European Commission Stage I limits on emissions of regulated pollutants: carbon monoxide, hydrocarbons, and oxides of nitrogen. We conducted a physical and economic evaluation of the environmental and health benefits from a reduction in emissions through this mandated environmental technology against the costs, with reference to urban areas in Great Britain. We made both an ex post assessment--based on available data to 1998--and an ex ante assessment--projected to 2005, the year when full penetration of VECs into the fleet is expected. Substantial health benefits in excess of the costs of VECs were indicated: By 1998 the estimated net societal health benefits were approximately 500 million British pounds, and by 2005 they were estimated to rise to as much as 2 billion British pounds. We also found through environmental surveys that although lead in road dust has fallen by 50% in urban areas, platinum accumulations near roads have risen significantly, up to 90-fold higher than natural background levels. This rapid accumulation of platinum suggests further monitoring is warranted, although as yet there is no evidence of adverse health effects.

Targeting of AUF1 to vascular endothelial cells as a novel anti-aging therapy.

PubMed

He, Jian; Jiang, Ya-Feng; Liang, Liu; Wang, Du-Jin; Wei, Wen-Xin; Ji, Pan-Pan; Huang, Yao-Chan; Song, Hui; Lu, Xiao-Ling; Zhao, Yong-Xiang

2017-08-01

Inhibition of aging of vascular endothelial cells (VECs) may delay aging and prolong life. The goal of this study was to prepare anti-CD31 monoclonal antibody conjugated PEG-modified liposomes containing the AU-rich region connecting factor 1 (AUF1) gene (CD31-PILs-AUF1) and to explore the effects of targeting CD31-PILs-AUF1 to aging VECs. The mean particle sizes of various PEGylated immunoliposomes (PILs) were measured using a Zetasizer Nano ZS. Gel retardation assay was used to confirm whether PILs had encapsulated the AUF1 plasmid successfully. Fluorescence microscopy and flow cytometry were used to quantify binding of CD31-PILs-AUF1 to target cells. Flow cytometry was also used to analyze the cell cycles of aging bEnd3 cells treated with CD31-PILs-AUF1. We also developed an aging mouse model by treating mice with D-galactose. Enzyme-linked immunosorbent assay (ELISA) was used to evaluate the levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). The malondialdehyde (MDA) and the superoxide dismutase (SOD) levels were detected by commercial kits. Hematoxylin-eosin (HE) staining was used to determine whether treatment with CD31-PILs-AUF1 was toxic to the mice. CD31-PILs-AUF1 specifically could targeted bEnd3 VECs and increased the percentage of cells in the S and G2/M phases of aging bEnd3 cells. ELISA showed that content of the IL-6 and TNF-α decreased in CD31-PILs-AUF1 group. The level of SOD increased, whereas MDA decreased in the CD31-PILs-AUF1 group. Additionally, CD31-PILs-AUF1 was not toxic to the mice. CD31-PILs-AUF1 targets VECs and may delay their senescence.

Targeting of AUF1 to vascular endothelial cells as a novel anti-aging therapy

PubMed Central

He, Jian; Jiang, Ya-Feng; Liang, Liu; Wang, Du-Jin; Wei, Wen-Xin; Ji, Pan-Pan; Huang, Yao-Chan; Song, Hui; Lu, Xiao-Ling; Zhao, Yong-Xiang

2017-01-01

Background Inhibition of aging of vascular endothelial cells (VECs) may delay aging and prolong life. The goal of this study was to prepare anti-CD31 monoclonal antibody conjugated PEG-modified liposomes containing the AU-rich region connecting factor 1 (AUF1) gene (CD31-PILs-AUF1) and to explore the effects of targeting CD31-PILs-AUF1 to aging VECs. Methods The mean particle sizes of various PEGylated immunoliposomes (PILs) were measured using a Zetasizer Nano ZS. Gel retardation assay was used to confirm whether PILs had encapsulated the AUF1 plasmid successfully. Fluorescence microscopy and flow cytometry were used to quantify binding of CD31-PILs-AUF1 to target cells. Flow cytometry was also used to analyze the cell cycles of aging bEnd3 cells treated with CD31-PILs-AUF1. We also developed an aging mouse model by treating mice with D-galactose. Enzyme-linked immunosorbent assay (ELISA) was used to evaluate the levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). The malondialdehyde (MDA) and the superoxide dismutase (SOD) levels were detected by commercial kits. Hematoxylin-eosin (HE) staining was used to determine whether treatment with CD31-PILs-AUF1 was toxic to the mice. Results CD31-PILs-AUF1 specifically could targeted bEnd3 VECs and increased the percentage of cells in the S and G2/M phases of aging bEnd3 cells. ELISA showed that content of the IL-6 and TNF-α decreased in CD31-PILs-AUF1 group. The level of SOD increased, whereas MDA decreased in the CD31-PILs-AUF1 group. Additionally, CD31-PILs-AUF1 was not toxic to the mice. Conclusion CD31-PILs-AUF1 targets VECs and may delay their senescence. PMID:29089968

Effects of Cerium Oxide Nanoparticles on the Growth of Keratinocytes, Fibroblasts and Vascular Endothelial Cells in Cutaneous Wound Healing

PubMed Central

Chigurupati, Srinivasulu; Mughal, Mohamed R.; Okun, Eitan; Das, Soumen; Kumar, Amit; McCaffery, Michael; Seal, Sudipta; Mattson, Mark P.

2012-01-01

Rapid and effective wound healing requires a coordinated cellular response involving fibroblasts, keratinocytes and vascular endothelial cells (VECs). Impaired wound healing can result in multiple adverse health outcomes and, although antibiotics can forestall infection, treatments that accelerate wound healing are lacking. We now report that topical application of water soluble cerium oxide nanoparticles (Nanoceria) accelerates the healing of full-thickness dermal wounds in mice by a mechanism that involves enhancement of the proliferation and migration of fibroblasts, keratinocytes and VECs. The Nanoceria penetrated into the wound tissue and reduced oxidative damage to cellular membranes and proteins, suggesting a therapeutic potential for topical treatment of wounds with antioxidant nanoparticles. PMID:23266256

Implications of a light “dark Higgs” solution to the g μ - 2 discrepancy

DOE PAGES

Chen, Chien-Yi; Davoudiasl, Hooman; Marciano, William J.; ...

2016-02-05

A light scalar Φ with mass ≲1 GeV and muonic coupling O(10 -3) would explain the 3.5σ discrepancy between the Standard Model (SM) muon g-2 prediction and experiment. Such a scalar can be associated with a light remnant of the Higgs mechanism in the “dark” sector. We suggest Φ→l +l - bump hunting in μ→eνmore » $$\\vec{v}$$Φ, μ-p→ν μnΦ (muon capture), and K ±→μ ±νΦ decays as direct probes of this scenario. In a general setup, a potentially observable muon electric dipole moment ≲10 -23 e cm and lepton-flavor-violating decays τ→μ(e)Φ or μ→eΦ can also arise. A deviation in BR(H→μ +μ -) from SM expectations, due to Higgs coupling misalignment, can result depending on certain parameters. Here, we illustrate how the requisite interactions can be mediated by weak-scale vector-like leptons that typically lie within the reach of future LHC measurements.« less

Review: Hamiltonian Linearization of the Rest-Frame Instant Form of Tetrad Gravity in a Completely Fixed 3-Orthogonal Gauge: A Radiation Gauge for Background-Independent Gravitational Waves in a Post-Minkowskian Einstein Spacetime

NASA Astrophysics Data System (ADS)

Agresti, Juri; De Pietri, Roberto; Lusanna, Luca; Martucci, Luca

2004-05-01

In the framework of the rest-frame instant form of tetrad gravity, where the Hamiltonian is the weak ADM energy {\\hat E}ADM, we define a special completely fixed 3-orthogonal Hamiltonian gauge, corresponding to a choice of non-harmonic 4-coordinates, in which the independent degrees of freedom of the gravitational field are described by two pairs of canonically conjugate Dirac observables (DO) r_{\\bar a}(\\tau ,\\vec \\sigma ), \\pi_{\\bar a}(\\tau ,\\vec \\sigma ), \\bar a = 1,2. We define a Hamiltonian linearization of the theory, i.e. gravitational waves, without introducing any background 4-metric, by retaining only the linear terms in the DO's in the super-hamiltonian constraint (the Lichnerowicz equation for the conformal factor of the 3-metric) and the quadratic terms in the DO's in {\\hat E}ADM. We solve all the constraints of the linearized theory: this amounts to work in a well defined post-Minkowskian Christodoulou-Klainermann space-time. The Hamilton equations imply the wave equation for the DO's r_{\\bar a}(\\tau ,\\vec \\sigma ), which replace the two polarizations of the TT harmonic gauge, and that linearized Einstein's equations are satisfied. Finally we study the geodesic equation, both for time-like and null geodesics, and the geodesic deviation equation.

Role of Vascular Endothelial Cells in Disseminated Intravascular Coagulation Induced by Seawater Immersion in a Rat Trauma Model

PubMed Central

Zhang, Dajin; Qu, Jia; Xiong, Ming; Qiao, Yuanyuan; Wang, Dapeng; Liu, Fengjiao; Li, Dandan; Hu, Ming; Zhang, Jiashu

2017-01-01

Trauma complicated by seawater immersion is a complex pathophysiological process with higher mortality than trauma occurring on land. This study investigated the role of vascular endothelial cells (VECs) in trauma development in a seawater environment. An open abdominal injury rat model was used. The rat core temperatures in the seawater (SW, 22°C) group and normal sodium (NS, 22°C) group declined equivalently. No rats died within 12 hours in the control and NS groups. However, the median lethal time of the rats in the SW group was only 260 minutes. Among the 84 genes involved in rat VEC biology, the genes exhibiting the high expression changes (84.62%, 11/13) on a qPCR array were associated with thrombin activity. The plasma activated partial thromboplastin time and fibrinogen and vWF levels decreased, whereas the prothrombin time and TFPI levels increased, indicating intrinsic and extrinsic coagulation pathway activation and inhibition, respectively. The plasma plasminogen, FDP, and D-dimer levels were elevated after 2 hours, and those of uPA, tPA, and PAI-1 exhibited marked changes, indicating disseminated intravascular coagulation (DIC). Additionally, multiorgan haemorrhagia was observed. It indicated that seawater immersion during trauma may increase DIC, elevating mortality. VECs injury might play an essential role in this process. PMID:28744465

Real-time PCR to determine transgene copy number and to quantitate the biolocalization of adoptively transferred cells from EGFP-transgenic mice.

PubMed

Joshi, Molishree; Keith Pittman, H; Haisch, Carl; Verbanac, Kathryn

2008-09-01

Quantitative real-time PCR (qPCR) is a sensitive technique for the detection and quantitation of specific DNA sequences. Here we describe a Taqman qPCR assay for quantification of tissue-localized, adoptively transferred enhanced green fluorescent protein (EGFP)-transgenic cells. A standard curve constructed from serial dilutions of a plasmid containing the EGFP transgene was (i) highly reproducible, (ii) detected as few as two copies, and (iii) was included in each qPCR assay. qPCR analysis of genomic DNA was used to determine transgene copy number in several mouse strains. Fluorescent microscopy of tissue sections showed that adoptively transferred vascular endothelial cells (VEC) from EGFP-transgenic mice specifically localized to tissue with metastatic tumors in syngeneic recipients. VEC microscopic enumeration of liver metastases strongly correlated with qPCR analysis of identical sections (Pearson correlation 0.81). EGFP was undetectable in tissue from control mice by qPCR. In another study using intra-tumor EGFP-VEC delivery to subcutaneous tumors, manual cell count and qPCR analysis of alternating sections also strongly correlated (Pearson correlation 0.82). Confocal microscopy of the subcutaneous tumor sections determined that visual fluorescent signals were frequently tissue artifacts. This qPCR methodology offers specific, objective, and rapid quantitation, uncomplicated by tissue autofluorescence, and should be readily transferable to other in vivo models to quantitate the biolocalization of transplanted cells.

Algorithm research for user trajectory matching across social media networks based on paragraph2vec

NASA Astrophysics Data System (ADS)

Xu, Qian; Chen, Hongchang; Zhi, Hongxin; Wang, Yanchuan

2018-04-01

Identifying users across different social media networks (SMN) is to link accounts of the same user that belong to the same individual across SMNs. The problem is fundamental and important, and its results can benefit many applications such as cross SMN user modeling and recommendation. With the development of GPS technology and mobile communication, more and more social networks provide location services. This provides a new opportunity for cross SMN user identification. In this paper, we solve cross SMN user identification problem in an unsupervised manner by utilizing user trajectory data in SMNs. A paragraph2vec based algorithm is proposed in which location sequence feature of user trajectory is captured in temporal and spatial dimensions. Our experimental results validate the effectiveness and efficiency of our algorithm.

Targeting annexin A7 by a small molecule suppressed the activity of phosphatidylcholine-specific phospholipase C in vascular endothelial cells and inhibited atherosclerosis in apolipoprotein E⁻/⁻mice.

PubMed

Li, H; Huang, S; Wang, S; Zhao, J; Su, L; Zhao, B; Zhang, Y; Zhang, S; Miao, J

2013-09-19

Phosphatidylcholine-specific phospholipase C (PC-PLC) is a key factor in apoptosis and autophagy of vascular endothelial cells (VECs), and involved in atherosclerosis in apolipoprotein E⁻/⁻ (apoE⁻/⁻) mice. But the endogenous regulators of PC-PLC are not known. We recently found a small chemical molecule (6-amino-2, 3-dihydro-3-hydroxymethyl-1, 4-benzoxazine, ABO) that could inhibit oxidized low-density lipoprotein (oxLDL)-induced apoptosis and promote autophagy in VECs, and further identified ABO as an inhibitor of annexin A7 (ANXA7) GTPase. Based on these findings, we hypothesize that ANXA7 is an endogenous regulator of PC-PLC, and targeting ANXA7 by ABO may inhibit atherosclerosis in apoE⁻/⁻ mice. In this study, we tested our hypothesis. The results showed that ABO suppressed oxLDL-induced increase of PC-PLC level and activity and promoted the co-localization of ANXA7 and PC-PLC in VECs. The experiments of ANXA7 knockdown and overexpression demonstrated that the action of ABO was ANXA7-dependent in cultured VECs. To investigate the relation of ANXA7 with PC-PLC in atherosclerosis, apoE⁻/⁻ mice fed with a western diet were treated with 50 or 100 mg/kg/day ABO. The results showed that ABO decreased PC-PLC levels in the mouse aortic endothelium and PC-PLC activity in serum, and enhanced the protein levels of ANXA7 in the mouse aortic endothelium. Furthermore, both dosages of ABO significantly enhanced autophagy and reduced apoptosis in the mouse aortic endothelium. As a result, ABO significantly reduced atherosclerotic plaque area and effectively preserved a stable plaques phenotype, including reduced lipid deposition and pro-inflammatory macrophages, increased anti-inflammatory macrophages, collagen content and smooth muscle cells, and less cell death in the plaques. In conclusion, ANXA7 was an endogenous regulator of PC-PLC, and targeting ANXA7 by ABO inhibited atherosclerosis in apoE⁻/⁻ mice.

Role of MUC4-NIDO domain in the MUC4-mediated metastasis of pancreatic cancer cells

PubMed Central

Senapati, Shantibhusan; Gnanapragassam, Vinayaga Srinivasan; Moniaux, Nicolas; Momi, Navneet; Batra, Surinder K.

2011-01-01

MUC4 is a large transmembrane type I glycoprotein that is overexpressed in pancreatic cancer (PC) and has been shown to be associated with its progression and metastasis. However, the exact cellular and molecular mechanism(s) through which MUC4 promotes metastasis of PC cells has been sparsely studied. Here we showed that the NIDO domain of MUC4, which is similar to the G1-domain present in the nidogen or entactin (an extracellular matrix protein), contributes to the protein-protein interaction property of MUC4. By this interaction, MUC4 promotes breaching of basement membrane integrity, and spreading of cancer cells. These observations are corroborated with the data from our study using an engineered MUC4 protein without the NIDO domain, which was ectopically expressed in the MiaPaCa PC cells, lacking endogenous MUC4 and nidogen protein. The in vitro studies demonstrated an enhanced invasiveness of MiaPaCa cells expressing MUC4 (MiaPaCa-MUC4) compared to vector-transfected cells (MiaPaCa-Vec; p=0.003) or cells expressing MUC4 without the NIDO domain (MiaPaCa-MUC4-NIDOΔ; p=0.03). However, the absence of NIDO-domain has no significant role on cell growth and motility (p=0.93). In the in-vivo studies, all the mice orthotopically implanted with MiPaCa-MUC4 cells developed metastasis to the liver as compared to MiaPaCa-Vec or the MiaPaCa-MUC4-NIDOΔ group, hence, supporting our in vitro observations. Additionally, a reduced binding (p=0.0004) of MiaPaCa-MUC4-NIDOΔ cells to the fibulin-2 coated plates compared to MiaPaCa-MUC4 cells indicated a possible interaction between the MUC4-NIDO domain and fibulin-2, a nidogen-interacting protein. Furthermore, in PC tissue samples, MUC4 colocalized with the fibulin-2 present in the basement membrane. Altogether, our findings demonstrate that the MUC4-NIDO domain significantly contributes to the MUC4-mediated metastasis of PC cells. This may be partly due to the interaction between the MUC4-NIDO domain and fibulin-2. PMID:22105367

Proceedings of the NASTRAN (Tradename) Users’ Colloquium (11th) Held in San Francisco, California on 2-6 May 1983

DTIC Science & Technology

1982-11-01

1430 2, 1, 0 1876 1988 1952 0, 1, 1 1953 1963 1928 1, 1, 1 2074 2089 2048 2, 1, 1 2401 2499 2440 3, 1, 0 2442 2875 2808 3, 1, 1 2866 3346 3233 f, n...PPFrPIDF/NOSET $ VEC USETD:/VP/*P*/*COMP*/*R* $ VEC USETI/Vt’/*D:*/*CDMP*/*R* $ PARTN PPF ,v VP/PPF1 ,PPF2yy,/ 1 $ PARTN PtIFv , VDi /P’I:FIP’F2, /I...PARTN MI)DtiVI:’, MDtti ,ML’D21 ,Mt’D1;2,MtiE122 $ PARTN BIIE’vVt’,/BLID). ,BiliD21 ,BDIl 2 BDE󈧚 $ PARTN KDlL’ VDI ,/KI:II vKDEI2i ,K~Ith2, KEIE󈧚

Query Auto-Completion Based on Word2vec Semantic Similarity

NASA Astrophysics Data System (ADS)

Shao, Taihua; Chen, Honghui; Chen, Wanyu

2018-04-01

Query auto-completion (QAC) is the first step of information retrieval, which helps users formulate the entire query after inputting only a few prefixes. Regarding the models of QAC, the traditional method ignores the contribution from the semantic relevance between queries. However, similar queries always express extremely similar search intention. In this paper, we propose a hybrid model FS-QAC based on query semantic similarity as well as the query frequency. We choose word2vec method to measure the semantic similarity between intended queries and pre-submitted queries. By combining both features, our experiments show that FS-QAC model improves the performance when predicting the user’s query intention and helping formulate the right query. Our experimental results show that the optimal hybrid model contributes to a 7.54% improvement in terms of MRR against a state-of-the-art baseline using the public AOL query logs.

VEGF promotes tumorigenesis and angiogenesis of human glioblastoma stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oka, Naoki; Soeda, Akio; Inagaki, Akihito

2007-08-31

There is increasing evidence for the presence of cancer stem cells (CSCs) in malignant brain tumors, and these CSCs may play a pivotal role in tumor initiation, growth, and recurrence. Vascular endothelial growth factor (VEGF) promotes the proliferation of vascular endothelial cells (VECs) and the neurogenesis of neural stem cells. Using CSCs derived from human glioblastomas and a retrovirus expressing VEGF, we examined the effects of VEGF on the properties of CSCs in vitro and in vivo. Although VEGF did not affect the property of CSCs in vitro, the injection of mouse brains with VEGF-expressing CSCs led to the massivemore » expansion of vascular-rich GBM, tumor-associated hemorrhage, and high morbidity, suggesting that VEGF promoted tumorigenesis via angiogenesis. These results revealed that VEGF induced the proliferation of VEC in the vascular-rich tumor environment, the so-called stem cell niche.« less

Hierarchical Rhetorical Sentence Categorization for Scientific Papers

NASA Astrophysics Data System (ADS)

Rachman, G. H.; Khodra, M. L.; Widyantoro, D. H.

2018-03-01

Important information in scientific papers can be composed of rhetorical sentences that is structured from certain categories. To get this information, text categorization should be conducted. Actually, some works in this task have been completed by employing word frequency, semantic similarity words, hierarchical classification, and the others. Therefore, this paper aims to present the rhetorical sentence categorization from scientific paper by employing TF-IDF and Word2Vec to capture word frequency and semantic similarity words and employing hierarchical classification. Every experiment is tested in two classifiers, namely Naïve Bayes and SVM Linear. This paper shows that hierarchical classifier is better than flat classifier employing either TF-IDF or Word2Vec, although it increases only almost 2% from 27.82% when using flat classifier until 29.61% when using hierarchical classifier. It shows also different learning model for child-category can be built by hierarchical classifier.

The loss-of-allele assay for ES cell screening and mouse genotyping.

PubMed

Frendewey, David; Chernomorsky, Rostislav; Esau, Lakeisha; Om, Jinsop; Xue, Yingzi; Murphy, Andrew J; Yancopoulos, George D; Valenzuela, David M

2010-01-01

Targeting vectors used to create directed mutations in mouse embryonic stem (ES) cells consist, in their simplest form, of a gene for drug selection flanked by mouse genomic sequences, the so-called homology arms that promote site-directed homologous recombination between the vector and the target gene. The VelociGene method for the creation of targeted mutations in ES cells employs targeting vectors, called BACVecs, that are based on bacterial artificial chromosomes. Compared with conventional short targeting vectors, BacVecs provide two major advantages: (1) their much larger homology arms promote high targeting efficiencies without the need for isogenicity or negative selection strategies; and (2) they enable deletions and insertions of up to 100kb in a single targeting event, making possible gene-ablating definitive null alleles and other large-scale genomic modifications. Because of their large arm sizes, however, BACVecs do not permit screening by conventional assays, such as long-range PCR or Southern blotting, that link the inserted targeting vector to the targeted locus. To exploit the advantages of BACVecs for gene targeting, we inverted the conventional screening logic in developing the loss-of-allele (LOA) assay, which quantifies the number of copies of the native locus to which the mutation was directed. In a correctly targeted ES cell clone, the LOA assay detects one of the two native alleles (for genes not on the X or Y chromosome), the other allele being disrupted by the targeted modification. We apply the same principle in reverse as a gain-of-allele assay to quantify the copy number of the inserted targeting vector. The LOA assay reveals a correctly targeted clone as having lost one copy of the native target gene and gained one copy of the drug resistance gene or other inserted marker. The combination of these quantitative assays makes LOA genotyping unequivocal and amenable to automated scoring. We use the quantitative polymerase chain reaction (qPCR) as our method of allele quantification, but any method that can reliably distinguish the difference between one and two copies of the target gene can be used to develop an LOA assay. We have designed qPCR LOA assays for deletions, insertions, point mutations, domain swaps, conditional, and humanized alleles and have used the insert assays to quantify the copy number of random insertion BAC transgenics. Because of its quantitative precision, specificity, and compatibility with high throughput robotic operations, the LOA assay eliminates bottlenecks in ES cell screening and mouse genotyping and facilitates maximal speed and throughput for knockout mouse production. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Integrated data analysis identifies potential inducers and pathways during the endothelial differentiation of bone-marrow stromal cells by DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine.

PubMed

Xu, Rui; Chen, Wenbin; Zhang, Zhifen; Qiu, Yang; Wang, Yong; Zhang, Bingchang; Lu, Wei

2018-05-30

Bone-Marrow Stromal Cells (BMSCs)-derived vascular endothelial cells (VECs) is regarded as an important therapeutic strategy for spinal cord injury, disc degeneration, cerebral ischemic disease and diabetes. The change in DNA methylation level is essential for stem cell differentiation. However, the DNA methylation related mechanisms underlying the endothelial differentiation of BMSCs are not well understood. In this study, DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine (5-aza-dC) significantly elevated the endothelial markers expression (CD31/PECAM1, CD105/ENG, eNOS and VE-cadherin), as well as promoted the capacity of angiogenesis on Matrigel. The result of Alexa 488-Ac-LDL uptake assay indicated that the differentiation ratio of BMSCs into VECs was 68.7% in 5-azaz-dC induced differentiation. And then we screened differentiation inducers with altered expression patterns and DNA methylation levels in four important families (VEGF, ANG, FGF and ETS). By integrating these data, five endothelial differentiation inducers (VEGFA, ANGPT2, FGF2, FGF9 and ETS1) which were directly upregulated by 5-aza-dC and five indirect factors (FGF1, FGF3, ETS2, ETV1 and ETV4) were identified. These data suggested that 5-aza-dC is an excellent chemical molecule for BMSCs differentiation into functional VECs and also provided essential clues for DNA methylation related signaling during 5-aza-dC induced endothelial differentiation of BMSCs. Copyright © 2018 Elsevier B.V. All rights reserved.

Poor response cycles: when should we cancel? Comparison of outcome between egg collection, intrauterine insemination conversion, and follow-up cycles after abandonment.

PubMed

Nicopoullos, James D M; Abdalla, Hossam

2011-01-01

To determine optimal management with one or two mature follicles after stimulation. Retrospective analysis. Lister fertility clinic. A total of 1,350 IVF/intracytoplasmic sperm injection cycles (7.3% of total) during 1998-2009 were found to have one or two mature follicles. Group 1 (n = 807) comprised those who proceeded to vaginal egg collection (VEC) (59.8%; outcome per egg collection), group 2 (n=248) those who converted to IUI (18.4%; outcome per insemination) and group 3 (n=259) those who abandoned the current cycle (21.9%; outcome per abandoned cycle in first subsequent cycle). Live birth rate, clinical pregnancy rate, and biochemical pregnancy rate. Biochemical pregnancy rates of 13.1%, 4.9%, and 9.7%, clinical pregnancy rates of 8.1%, 3.6%, and 7.2%, and ongoing pregnancy rates of 6.8%, 2.0%, and 5.5% were achieved in groups 1, 2, and 3, respectively. All pregnancy outcomes were significantly higher after VEC (group 1) than for those converted to IUI (group 2), and all pregnancy outcomes were higher with borderline significance in group 3 vs. group 2. There was no significant difference in outcome between groups 1 and 3. Our data suggest that for such poor responders, proceeding to VEC may represent their best chance of successful outcome. Conversion to IUI offers the poorest outcome, and despite the potential for improvements in cycle protocol, abandoning and a further attempt does not improve outcome (using abandoned cycle as the denominator). Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Effect of different dialyzer membranes on cutaneous microcirculation during hemodialysis.

PubMed

Sato, M; Morita, H; Ema, H; Yamaguchi, S; Amano, I

2006-12-01

Biocompatibility profiles of synthetic membranes may vary. In this prospective crossover study, we examined the effect of various membranes on cutaneous microcirculation during HD. 11 HD patients without cardiovascular complications were enrolled in this study. They were dialyzed using three types of membrane in a randomized order: ethylene-vinyl alcohol copolymer (EVAL), vitamin E-bonded cellulose (VE-C) and polysulfone (PS). The transcutaneous oxygen tension (TcPO2) was examined on the dorsum of foot to assess the cutaneous microcirculation. Serum biochemical parameters were also measured. The TcPO2 as a percentage of the predialysis level decreased from the beginning of HD, and significant differences were observed after 15 min of HD between EVAL and the other 2 membranes (98 +/- 6% (mean +/- SD) for EVAL versus 89 +/- 7% for VE-C (p < 0.01) and 88 +/- 10% for PS (p < 0.01)). Furthermore, there were significant differences at 30 and 60 min between EVAL and PS (30 min: 93 +/- 9% for EVAL versus 85 +/- 7% for PS (p < 0.05); 60 min: 92 +/- 10% for EVAL versus 79 +/- 10% for PS (p < 0.01)). The serum level of thiobarbituric acid reactants (TBARs), a marker of lipid peroxidation, increased significantly at the end of HD relative to that at the beginning of HD when using a PS membrane (from 1.9 +/- 0.5 to 2.1 +/- 0.5 nmol/ml, p < 0.05). Our results indicate that an EVAL membrane is superior to PS and VE-C membranes in terms of its smaller influence on cutaneous microcirculation. The repeated occurrence of microcirculatory disturbance during HD sessions may cause chronic endothelial dysfunction and even cardiovascular complications in HD patients.

Role of MUC4-NIDO domain in the MUC4-mediated metastasis of pancreatic cancer cells.

PubMed

Senapati, S; Gnanapragassam, V S; Moniaux, N; Momi, N; Batra, S K

2012-07-12

MUC4 is a large transmembrane type I glycoprotein that is overexpressed in pancreatic cancer (PC) and has been shown to be associated with its progression and metastasis. However, the exact cellular and molecular mechanism(s) through which MUC4 promotes metastasis of PC cells has been sparsely studied. Here we showed that the nidogen-like (NIDO) domain of MUC4, which is similar to the G1-domain present in the nidogen or entactin (an extracellular matrix protein), contributes to the protein-protein interaction property of MUC4. By this interaction, MUC4 promotes breaching of basement membrane (BM) integrity, and spreading of cancer cells. These observations are corroborated with the data from our study using an engineered MUC4 protein without the NIDO domain, which was ectopically expressed in the MiaPaCa PC cells, lacking endogenous MUC4 and nidogen protein. The in vitro studies demonstrated an enhanced invasiveness of MiaPaCa cells expressing MUC4 (MiaPaCa-MUC4) compared with vector-transfected cells (MiaPaCa-Vec; P=0.003) or cells expressing MUC4 without the NIDO domain (MiaPaCa-MUC4-NIDO(Δ); P=0.03). However, the absence of NIDO-domain has no significant role on cell growth and motility (P=0.93). In the in vivo studies, all the mice orthotopically implanted with MiPaCa-MUC4 cells developed metastasis to the liver as compared with MiaPaCa-Vec or the MiaPaCa-MUC4-NIDO(Δ) group, hence, supporting our in vitro observations. Additionally, a reduced binding (P=0.0004) of MiaPaCa-MUC4-NIDO(Δ) cells to the fibulin-2 coated plates compared with MiaPaCa-MUC4 cells indicated a possible interaction between the MUC4-NIDO domain and fibulin-2, a nidogen-interacting protein. Furthermore, in PC tissue samples, MUC4 colocalized with the fibulin-2 present in the BM. Altogether, our findings demonstrate that the MUC4-NIDO domain significantly contributes to the MUC4-mediated metastasis of PC cells. This may be partly due to the interaction between the MUC4-NIDO domain and fibulin-2.

Efficiency Improvement in a Busy Radiology Practice: Determination of Musculoskeletal Magnetic Resonance Imaging Protocol Using Deep-Learning Convolutional Neural Networks.

PubMed

Lee, Young Han

2018-04-04

The purposes of this study are to evaluate the feasibility of protocol determination with a convolutional neural networks (CNN) classifier based on short-text classification and to evaluate the agreements by comparing protocols determined by CNN with those determined by musculoskeletal radiologists. Following institutional review board approval, the database of a hospital information system (HIS) was queried for lists of MRI examinations, referring department, patient age, and patient gender. These were exported to a local workstation for analyses: 5258 and 1018 consecutive musculoskeletal MRI examinations were used for the training and test datasets, respectively. The subjects for pre-processing were routine or tumor protocols and the contents were word combinations of the referring department, region, contrast media (or not), gender, and age. The CNN Embedded vector classifier was used with Word2Vec Google news vectors. The test set was tested with each classification model and results were output as routine or tumor protocols. The CNN determinations were evaluated using the receiver operating characteristic (ROC) curves. The accuracies were evaluated by a radiologist-confirmed protocol as the reference protocols. The optimal cut-off values for protocol determination between routine protocols and tumor protocols was 0.5067 with a sensitivity of 92.10%, a specificity of 95.76%, and an area under curve (AUC) of 0.977. The overall accuracy was 94.2% for the ConvNet model. All MRI protocols were correct in the pelvic bone, upper arm, wrist, and lower leg MRIs. Deep-learning-based convolutional neural networks were clinically utilized to determine musculoskeletal MRI protocols. CNN-based text learning and applications could be extended to other radiologic tasks besides image interpretations, improving the work performance of the radiologist.

47 CFR 97.527 - Reimbursement for expenses.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Reimbursement for expenses. 97.527 Section 97... AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.527 Reimbursement for expenses. VEs and VECs may be reimbursed by examinees for out-of-pocket expenses incurred in preparing, processing...

A Contemporary Treatment Approach to Both Diabetes and Depression by Cordyceps sinensis, Rich in Vanadium

PubMed Central

Guo, Jian-You; Han, Chun-Chao

2010-01-01

Diabetes mellitus is accompanied by hormonal and neurochemical changes that can be associated with anxiety and depression. Both diabetes and depression negatively interact, in that depression leads to poor metabolic control and hyperglycemia exacerbates depression. We hypothesize one novel vanadium complex of vanadium-enriched Cordyceps sinensis (VECS), which is beneficial in preventing depression in diabetes, and influences the long-term course of glycemic control. Vanadium compounds have the ability to imitate the action of insulin, and this mimicry may have further favorable effects on the level of treatment satisfaction and mood. C. sinensis has an antidepressant-like activity, and attenuates the diabetes-induced increase in blood glucose concentrations. We suggest that the VECS may be a potential strategy for contemporary treatment of depression and diabetes through the co-effect of C. sinensis and vanadium. The validity of the hypothesis can most simply be tested by examining blood glucose levels, and swimming and climbing behavior in streptozotocin-induced hyperglycemic rats. PMID:19948751

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, A.; Avakian, H.; Burkert, V.

The target and double spin asymmetries of the exclusive pseudoscalar channelmore » $$\\vec e\\vec p\\to ep\\pi^0$$ were measured for the first time in the deep-inelastic regime using a longitudinally polarized 5.9 GeV electron beam and a longitudinally polarized proton target at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS). The data were collected over a large kinematic phase space and divided into 110 four-dimensional bins of $Q^2$, $$x_B$$, $-t$ and $$\\phi$$. Large values of asymmetry moments clearly indicate a substantial contribution to the polarized structure functions from transverse virtual photon amplitudes. The interpretation of experimental data in terms of generalized parton distributions (GPDs) provides the first insight on the chiral-odd GPDs $$\\tilde{H}_T$$ and $$E_T$$, and complement previous measurements of unpolarized structure functions sensitive to the GPDs $$H_T$$ and $$\\bar E_T$$. Finally, these data provide necessary constraints for chiral-odd GPD parametrizations and will strongly influence existing theoretical handbag models.« less

Gamow-Teller Strength in the Continuum Studied via the (p,n) Reaction

NASA Astrophysics Data System (ADS)

Wakasa, T.; Hatanaka, K.; Sakai, H.; Fujita, S.; Nonaka, T.; Ohnishi, T.; Yako, K.; Sekiguchi, K.; Okamura, H.; Otsu, H.; Ishida, S.; Sakamoto, N.; Uesaka, T.; Satou, Y.; Greenfield, M. B.

2002-09-01

The double differential cross sections for θ1ab between 0.0° and 14.7° and the polarization transfer coefficient DNN(0°) for the 27 Al(vec {p},vec {n}) reaction have been measured at a bombarding energy of 295 MeV. A multipole decomposition technique is applied for the cross section data to extract L = 0, 1, 2, and 3 contributions. The Gamow-Teller (GT) strength B(GT) deduced from the L = 0 contribution is compared with the B(GT) values calculated in a full sd shell-model space. The sum of B(GT) values up to 20 MeV excitation is Sβ- = 4.0 ± 0.1 ± 0.1. A fairly large L = 0 contribution is observed in the continuum region up to 50 MeV, which could be in part ascribed to the quenched GT strength. A limit on the effect that the Δ(1232)-isobar nucleon-hole admixture has upon the GT strength is estimated.

47 CFR Appendix 2 to Part 97 - VEC Regions

Code of Federal Regulations, 2010 CFR

2010-10-01

... Hampshire, Rhode Island and Vermont. 2. New Jersey and New York. 3. Delaware, District of Columbia, Maryland and Pennsylvania. 4. Alabama, Florida, Georgia, Kentucky, North Carolina, South Carolina, Tennessee... Dakota and South Dakota. 11. Alaska. 12. Caribbean Insular areas. 13. Hawaii and Pacific Insular areas. ...

47 CFR Appendix 2 to Part 97 - VEC Regions

Code of Federal Regulations, 2012 CFR

2012-10-01

... Hampshire, Rhode Island and Vermont. 2. New Jersey and New York. 3. Delaware, District of Columbia, Maryland and Pennsylvania. 4. Alabama, Florida, Georgia, Kentucky, North Carolina, South Carolina, Tennessee... Dakota and South Dakota. 11. Alaska. 12. Caribbean Insular areas. 13. Hawaii and Pacific Insular areas. ...

47 CFR Appendix 2 to Part 97 - VEC Regions

Code of Federal Regulations, 2013 CFR

2013-10-01

... Hampshire, Rhode Island and Vermont. 2. New Jersey and New York. 3. Delaware, District of Columbia, Maryland and Pennsylvania. 4. Alabama, Florida, Georgia, Kentucky, North Carolina, South Carolina, Tennessee... Dakota and South Dakota. 11. Alaska. 12. Caribbean Insular areas. 13. Hawaii and Pacific Insular areas. ...

47 CFR Appendix 2 to Part 97 - VEC Regions

Code of Federal Regulations, 2011 CFR

2011-10-01

... Hampshire, Rhode Island and Vermont. 2. New Jersey and New York. 3. Delaware, District of Columbia, Maryland and Pennsylvania. 4. Alabama, Florida, Georgia, Kentucky, North Carolina, South Carolina, Tennessee... Dakota and South Dakota. 11. Alaska. 12. Caribbean Insular areas. 13. Hawaii and Pacific Insular areas. ...

Uniform Interfaces for Distributed Systems.

DTIC Science & Technology

1980-05-01

in data str ’.ctures on stable storage (such as disk). The Virtual Terminals associated with a particular user (i.e., rM display terminal) are all...vec MESSAGESIZE let error = nil [S ReceiveAny (msg) // The copy is made so that lower-level routines may // munge the message template without losing

Using Oncolytic Viruses to Treat Cancer

Cancer.gov

Cancer treatments known as oncolytic viruses are being tested in clinical trials, and one, T-VEC or Imlygic®, has been approved by the FDA. Research now suggests that these treatments work not only by infecting and killing tumor cells, but that they may also be a form of cancer immunotherapy.

Spotlight on VET: Ireland

ERIC Educational Resources Information Center

Cedefop - European Centre for the Development of Vocational Training, 2013

2013-01-01

This paper provides an overview of VET (vocational education and training) in Ireland. In Ireland, the main providers of VET are the national Training and Employment Authority (FAS--a non-commercial semi-State body, part of the public sector) and vocational education committees (VECs--public sector bodies at county level responsible for vocational…

47 CFR 97.519 - Coordinating examination sessions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... qualified examinees, forward electronically all required data to the FCC. All data forwarded must be... itself or under the supervision of a VEC or VEs designated by the FCC; or (3) Cancel the operator/primary... instancce of such cancellation, the person will be granted an operator/primary station license consistent...

Application of genetically engineered Salmonella typhimurium for interferon-gamma-induced therapy against melanoma.

PubMed

Yoon, Wonsuck; Park, Yoo Chang; Kim, Jinseok; Chae, Yang Seok; Byeon, Jung Hye; Min, Sang-Hyun; Park, Sungha; Yoo, Young; Park, Yong Keun; Kim, Byeong Mo

2017-01-01

Salmonella have been experimentally used as anti-cancer agents, because they show selective growth in tumours. In this study, we genetically modified attenuated Salmonella typhimurium to express and secrete interferon-gamma (IFN-γ) as a tumouricidal agent to enhance the therapeutic efficacy of Salmonella. IFN-γ was fused to the N-terminal region (residues 1-160) of SipB (SipB160) for secretion from bacterial cells. Attenuated S. typhimurium expressing recombinant IFN-γ (S. typhimurium (IFN-γ)) invaded the melanoma cells and induced cytotoxicity. Subcutaneous administration of S. typhimurium (IFN-γ) also efficiently inhibited tumour growth and prolonged the survival of C57BL/6 mice bearing B16F10 melanoma compared with administration of phosphate-buffered saline (PBS), unmodified S. typhimurium or S. typhimurium expressing empty vector (S. typhimurium [Vec]) in a natural killer (NK) cell-dependent manner. Moreover, genetically modified Salmonella, including S. typhimurium (IFN-γ), showed little toxicity to normal tissues with no observable adverse effects. However, S. typhimurium (IFN-γ)-mediated tumour suppression was attributed to direct killing of tumour cells rather than to stable anti-tumour immunity. Collectively, these results suggest that tumour-targeted therapy using S. typhimurium (IFN-γ) has potential for melanoma treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

76 FR 65713 - Combined Notice of Filings #1

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-24

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 1 Take notice.... submits tariff filing per 35.17(b): Supplemental Filing to Schedule 21-VEC Revisions to be effective 4/1... effective 12/1/2011. Filed Date: 10/13/2011. Accession Number: 20111013-5038. Comment Date: 5 p.m. Eastern...

An Exploration of Female Travellers' Experiences of Guidance Counselling in Adult Education

ERIC Educational Resources Information Center

Doyle, Anne; Hearne, Lucy

2012-01-01

The proposed changes in the further education sector, including the rationalisation of the VEC into Local Education and Training Boards (LETBs) and the closures of the Senior Traveller Training Centres (STTCs), have implications for guidance counselling provision to the Traveller community. This article discusses female Travellers' experiences of…

A Collaborative Virtual Environment for Situated Language Learning Using VEC3D

ERIC Educational Resources Information Center

Shih, Ya-Chun; Yang, Mau-Tsuen

2008-01-01

A 3D virtually synchronous communication architecture for situated language learning has been designed to foster communicative competence among undergraduate students who have studied English as a foreign language (EFL). We present an innovative approach that offers better e-learning than the previous virtual reality educational applications. The…

Calcium ion propagation in cultured keratinocytes and other cells in skin in response to hydraulic pressure stimulation.

PubMed

Goto, Makiko; Ikeyama, Kazuyuki; Tsutsumi, Moe; Denda, Sumiko; Denda, Mitsuhiro

2010-07-01

We have previously suggested that a variety of environmental factors might be first sensed by epidermal keratinocytes, which represent the frontier of the body. To further examine this idea, in the present study, we examined the intracellular calcium responses of cultured keratinocytes to external hydraulic pressure. First, we compared the responses of undifferentiated and differentiated keratinocytes with those of fibroblasts, vascular endothelial cells (VEC), and lymphatic endothelial cells. Elevation of intracellular calcium was observed after application of pressure to keratinocytes, fibroblasts, and VEC. The calcium propagation extended over a larger area and continued for a longer period of time in differentiated keratinocytes, as compared with the other cells. The response of the keratinocytes was dramatically reduced when the cells were incubated in medium without calcium. Application of a non-selective transient receptor potential (TRP) channel blocker also attenuated the calcium response. These results suggest that differentiated keratinocytes are sensitive to external pressure and that TRP might be involved in the mechanism of their response. (c) 2010 Wiley-Liss, Inc.

Escherichia coli K1 invasion increases human brain microvascular endothelial cell monolayer permeability by disassembling vascular-endothelial cadherins at tight junctions.

PubMed

Sukumaran, Sunil K; Prasadarao, Nemani V

2003-11-01

We investigated the permeability changes that occur in the human brain microvascular endothelial cell (HBMEC) monolayer, an in vitro model of the blood-brain barrier, during Escherichia coli K1 infection. An increase in permeability of HBMECs and a decrease in transendothelial electrical resistance were observed. These permeability changes occurred only when HBMECs were infected with E. coli expressing outer membrane protein A (OmpA) and preceded the traversal of bacteria across the monolayer. Activated protein kinase C (PKC)-alpha interacts with vascular-endothelial cadherins (VECs) at the tight junctions of HBMECs, resulting in the dissociation of beta-catenins from VECs and leading to the increased permeability of the HBMEC monolayer. Overexpression of a dominant negative form of PKC-alpha in HBMECs blocked the E. coli-induced increase in permeability of HBMECs. Anti-OmpA and anti-OmpA receptor antibodies exerted inhibition of E. coli-induced permeability of HBMEC monolayers. This inhibition was the result of the absence of PKC-alpha activation in HBMECs treated with the antibodies.

Target and double spin asymmetries of deeply virtual π 0 production with a longitudinally polarized proton target and CLAS

DOE PAGES

Kim, A.; Avakian, H.; Burkert, V.; ...

2017-02-22

The target and double spin asymmetries of the exclusive pseudoscalar channelmore » $$\\vec e\\vec p\\to ep\\pi^0$$ were measured for the first time in the deep-inelastic regime using a longitudinally polarized 5.9 GeV electron beam and a longitudinally polarized proton target at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS). The data were collected over a large kinematic phase space and divided into 110 four-dimensional bins of $Q^2$, $$x_B$$, $-t$ and $$\\phi$$. Large values of asymmetry moments clearly indicate a substantial contribution to the polarized structure functions from transverse virtual photon amplitudes. The interpretation of experimental data in terms of generalized parton distributions (GPDs) provides the first insight on the chiral-odd GPDs $$\\tilde{H}_T$$ and $$E_T$$, and complement previous measurements of unpolarized structure functions sensitive to the GPDs $$H_T$$ and $$\\bar E_T$$. Finally, these data provide necessary constraints for chiral-odd GPD parametrizations and will strongly influence existing theoretical handbag models.« less

An efficient and portable SIMD algorithm for charge/current deposition in Particle-In-Cell codes

DOE PAGES

Vincenti, H.; Lobet, M.; Lehe, R.; ...

2016-09-19

In current computer architectures, data movement (from die to network) is by far the most energy consuming part of an algorithm (≈20pJ/word on-die to ≈10,000 pJ/word on the network). To increase memory locality at the hardware level and reduce energy consumption related to data movement, future exascale computers tend to use many-core processors on each compute nodes that will have a reduced clock speed to allow for efficient cooling. To compensate for frequency decrease, machine vendors are making use of long SIMD instruction registers that are able to process multiple data with one arithmetic operator in one clock cycle. SIMD registermore » length is expected to double every four years. As a consequence, Particle-In-Cell (PIC) codes will have to achieve good vectorization to fully take advantage of these upcoming architectures. In this paper, we present a new algorithm that allows for efficient and portable SIMD vectorization of current/charge deposition routines that are, along with the field gathering routines, among the most time consuming parts of the PIC algorithm. Our new algorithm uses a particular data structure that takes into account memory alignment constraints and avoids gather/scat;ter instructions that can significantly affect vectorization performances on current CPUs. The new algorithm was successfully implemented in the 3D skeleton PIC code PICSAR and tested on Haswell Xeon processors (AVX2-256 bits wide data registers). Results show a factor of ×2 to ×2.5 speed-up in double precision for particle shape factor of orders 1–3. The new algorithm can be applied as is on future KNL (Knights Landing) architectures that will include AVX-512 instruction sets with 512 bits register lengths (8 doubles/16 singles). Program summary Program Title: vec_deposition Program Files doi:http://dx.doi.org/10.17632/nh77fv9k8c.1 Licensing provisions: BSD 3-Clause Programming language: Fortran 90 External routines/libraries:  OpenMP > 4.0 Nature of problem: Exascale architectures will have many-core processors per node with long vector data registers capable of performing one single instruction on multiple data during one clock cycle. Data register lengths are expected to double every four years and this pushes for new portable solutions for efficiently vectorizing Particle-In-Cell codes on these future many-core architectures. One of the main hotspot routines of the PIC algorithm is the current/charge deposition for which there is no efficient and portable vector algorithm. Solution method: Here we provide an efficient and portable vector algorithm of current/charge deposition routines that uses a new data structure, which significantly reduces gather/scatter operations. Vectorization is controlled using OpenMP 4.0 compiler directives for vectorization which ensures portability across different architectures. Restrictions: Here we do not provide the full PIC algorithm with an executable but only vector routines for current/charge deposition. These scalar/vector routines can be used as library routines in your 3D Particle-In-Cell code. However, to get the best performances out of vector routines you have to satisfy the two following requirements: (1) Your code should implement particle tiling (as explained in the manuscript) to allow for maximized cache reuse and reduce memory accesses that can hinder vector performances. The routines can be used directly on each particle tile. (2) You should compile your code with a Fortran 90 compiler (e.g Intel, gnu or cray) and provide proper alignment flags and compiler alignment directives (more details in README file).« less

An efficient and portable SIMD algorithm for charge/current deposition in Particle-In-Cell codes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vincenti, H.; Lobet, M.; Lehe, R.

In current computer architectures, data movement (from die to network) is by far the most energy consuming part of an algorithm (≈20pJ/word on-die to ≈10,000 pJ/word on the network). To increase memory locality at the hardware level and reduce energy consumption related to data movement, future exascale computers tend to use many-core processors on each compute nodes that will have a reduced clock speed to allow for efficient cooling. To compensate for frequency decrease, machine vendors are making use of long SIMD instruction registers that are able to process multiple data with one arithmetic operator in one clock cycle. SIMD registermore » length is expected to double every four years. As a consequence, Particle-In-Cell (PIC) codes will have to achieve good vectorization to fully take advantage of these upcoming architectures. In this paper, we present a new algorithm that allows for efficient and portable SIMD vectorization of current/charge deposition routines that are, along with the field gathering routines, among the most time consuming parts of the PIC algorithm. Our new algorithm uses a particular data structure that takes into account memory alignment constraints and avoids gather/scat;ter instructions that can significantly affect vectorization performances on current CPUs. The new algorithm was successfully implemented in the 3D skeleton PIC code PICSAR and tested on Haswell Xeon processors (AVX2-256 bits wide data registers). Results show a factor of ×2 to ×2.5 speed-up in double precision for particle shape factor of orders 1–3. The new algorithm can be applied as is on future KNL (Knights Landing) architectures that will include AVX-512 instruction sets with 512 bits register lengths (8 doubles/16 singles). Program summary Program Title: vec_deposition Program Files doi:http://dx.doi.org/10.17632/nh77fv9k8c.1 Licensing provisions: BSD 3-Clause Programming language: Fortran 90 External routines/libraries:  OpenMP > 4.0 Nature of problem: Exascale architectures will have many-core processors per node with long vector data registers capable of performing one single instruction on multiple data during one clock cycle. Data register lengths are expected to double every four years and this pushes for new portable solutions for efficiently vectorizing Particle-In-Cell codes on these future many-core architectures. One of the main hotspot routines of the PIC algorithm is the current/charge deposition for which there is no efficient and portable vector algorithm. Solution method: Here we provide an efficient and portable vector algorithm of current/charge deposition routines that uses a new data structure, which significantly reduces gather/scatter operations. Vectorization is controlled using OpenMP 4.0 compiler directives for vectorization which ensures portability across different architectures. Restrictions: Here we do not provide the full PIC algorithm with an executable but only vector routines for current/charge deposition. These scalar/vector routines can be used as library routines in your 3D Particle-In-Cell code. However, to get the best performances out of vector routines you have to satisfy the two following requirements: (1) Your code should implement particle tiling (as explained in the manuscript) to allow for maximized cache reuse and reduce memory accesses that can hinder vector performances. The routines can be used directly on each particle tile. (2) You should compile your code with a Fortran 90 compiler (e.g Intel, gnu or cray) and provide proper alignment flags and compiler alignment directives (more details in README file).« less

Effective treatment of chemoresistant breast cancer in vitro and in vivo by a factor VII-targeted photodynamic therapy.

PubMed

Duanmu, J; Cheng, J; Xu, J; Booth, C J; Hu, Z

2011-04-26

The purpose of this study was to test a novel, dual tumour vascular endothelial cell (VEC)- and tumour cell-targeting factor VII-targeted Sn(IV) chlorin e6 photodynamic therapy (fVII-tPDT) by targeting a receptor tissue factor (TF) as an alternative treatment for chemoresistant breast cancer using a multidrug resistant (MDR) breast cancer line MCF-7/MDR. The TF expression by the MCF-7/MDR breast cancer cells and tumour VECs in MCF-7/MDR tumours from mice was determined separately by flow cytometry and immunohistochemistry using anti-human or anti-murine TF antibodies. The efficacy of fVII-tPDT was tested in vitro and in vivo and was compared with non-targeted PDT for treatment of chemoresistant breast cancer. The in vitro efficacy was determined by a non-clonogenic assay using crystal violet staining for monolayers, and apoptosis and necrosis were assayed to elucidate the underlying mechanisms. The in vivo efficacy of fVII-tPDT was determined in a nude mouse model of subcutaneous MCF-7/MDR tumour xenograft by measuring tumour volume. To our knowledge, this is the first presentation showing that TF was expressed on tumour VECs in chemoresistant breast tumours from mice. The in vitro efficacy of fVII-tPDT was 12-fold stronger than that of ntPDT for MCF-7/MDR cancer cells, and the mechanism of action involved induction of apoptosis and necrosis. Moreover, fVII-tPDT was effective and safe for the treatment of chemoresistant breast tumours in the nude mouse model. We conclude that fVII-tPDT is effective and safe for the treatment of chemoresistant breast cancer, presumably by simultaneously targeting both the tumour neovasculature and chemoresistant cancer cells. Thus, this dual-targeting fVII-tPDT could also have therapeutic potential for the treatment of other chemoresistant cancers.

Relativistic Effects and Gold Site Distributions: Synthesis, Structure, and Bonding in a Polar Intermetallic Na6Cd16Au7

DOE Office of Scientific and Technical Information (OSTI.GOV)

Samal, Saroj L.; Corbett, John D.

Na{sub 6}Cd{sub 16}Au{sub 7} has been synthesized via typical high-temperature reactions, and its structure refined by single crystal X-ray diffraction as cubic, Fm{bar 3}m, a = 13.589(1) {angstrom}, Z = 4. The structure consists of Cd{sub 8} tetrahedral star (TS) building blocks that are face capped by six shared gold (Au2) vertexes and further diagonally bridged via Au1 to generate an orthogonal, three-dimensional framework [Cd{sub 8}(Au2){sub 6/2}(Au1){sub 4/8}], an ordered ternary derivative of Mn{sub 6}Th{sub 23}. Linear muffin-tin-orbital (LMTO)-atomic sphere approximation (ASA) electronic structure calculations indicate that Na{sub 6}Cd{sub 16}Au{sub 7} is metallic and that {approx}76% of the total crystalmore » orbital Hamilton populations (-ICOHP) originate from polar Cd-Au bonding with 18% more from fewer Cd-Cd contacts. Na{sub 6}Cd{sub 16}Au{sub 7} (45 valence electron count (vec)) is isotypic with the older electron-richer Mg{sub 6}Cu{sub 16}Si{sub 7} (56 vec) in which the atom types are switched and bonding characteristics among the network elements are altered considerably (Si for Au, Cu for Cd, Mg for Na). The earlier and more electronegative element Au now occupies the Si site, in accord with the larger relativistic bonding contributions from polar Cd-Au versus Cu-Si bonds with the neighboring Cd in the former Cu positions. Substantial electronic differences in partial densities-of-states (PDOS) and COHP data for all atoms emphasize these. Strong contributions of nearby Au 5d{sup 10} to bonding states without altering the formal vec are the likely origin of these effects.« less

The effect of a beta-lactamase inhibitor peptide on bacterial membrane structure and integrity: a comparative study.

PubMed

Alaybeyoglu, Begum; Uluocak, Bilge Gedik; Akbulut, Berna Sariyar; Ozkirimli, Elif

2017-05-01

Co-administration of beta-lactam antibiotics and beta-lactamase inhibitors has been a favored treatment strategy against beta-lactamase-mediated bacterial antibiotic resistance, but the emergence of beta-lactamases resistant to current inhibitors necessitates the discovery of novel non-beta-lactam inhibitors. Peptides derived from the Ala46-Tyr51 region of the beta-lactamase inhibitor protein are considered as potent inhibitors of beta-lactamase; unfortunately, peptide delivery into the cell limits their potential. The properties of cell-penetrating peptides could guide the design of beta-lactamase inhibitory peptides. Here, our goal is to modify the peptide with the sequence RRGHYY that possesses beta-lactamase inhibitory activity under in vitro conditions. Inspired by the work on the cell-penetrating peptide pVEC, our approach involved the addition of the N-terminal hydrophobic residues, LLIIL, from pVEC to the inhibitor peptide to build a chimera. These residues have been reported to be critical in the uptake of pVEC. We tested the potential of RRGHYY and its chimeric derivative as a beta-lactamase inhibitory peptide on Escherichia coli cells and compared the results with the action of the antimicrobial peptide melittin, the beta-lactam antibiotic ampicillin, and the beta-lactamase inhibitor potassium clavulanate to get mechanistic details on their action. Our results show that the addition of LLIIL to the N-terminus of the beta-lactamase inhibitory peptide RRGHYY increases its membrane permeabilizing potential. Interestingly, the addition of this short stretch of hydrophobic residues also modified the inhibitory peptide such that it acquired antimicrobial property. We propose that addition of the hydrophobic LLIIL residues to the peptide N-terminus offers a promising strategy to design novel antimicrobial peptides in the battle against antibiotic resistance. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.

Valuing Puget Sound’s Valued Ecosystems Components

DTIC Science & Technology

2007-07-01

communicate the value of Puget Sound nearshore restoration to managers and the public, and are intended to speak to ecological and societal values...list of VECs is meant to represent a cross-section of organisms and physical structures that occupy and interact with the physical processes found in...7 Applying Economic Valuation Techniques to Ecological Resources

Development of single chain variable fragment (scFv) antibodies against surface proteins of ‘Ca. Liberibacter asiaticus’

USDA-ARS?s Scientific Manuscript database

‘Ca. Liberibacter asiaticus’ is the causal agent of citrus huanglongbing, the most serious disease of citrus worldwide. We have developed and applied immunization and affinity screening methods to develop a primary library of recombinant single chain variable fragment (scFv) antibodies in an M13 vec...

Average Nuclear Potentials from Selfconsistent Semiclassical Calculations

NASA Astrophysics Data System (ADS)

Bartel, J.

1999-03-01

Using the selfconsistent semiclassical Extended Thomas-Fermi (ETF) method up to 4th order in connection with Skyrme forces it is demonstrated that the neutron and proton average potentials obtained using the semiclassical functionals τ (ETF)[ρ] and vec {J}(ETF)[ρ] reproduce the corresponding Hartree-Fock fields extremely well, except for shell oscillations in the nuclear center.

PubRunner: A light-weight framework for updating text mining results.

PubMed

Anekalla, Kishore R; Courneya, J P; Fiorini, Nicolas; Lever, Jake; Muchow, Michael; Busby, Ben

2017-01-01

Biomedical text mining promises to assist biologists in quickly navigating the combined knowledge in their domain. This would allow improved understanding of the complex interactions within biological systems and faster hypothesis generation. New biomedical research articles are published daily and text mining tools are only as good as the corpus from which they work. Many text mining tools are underused because their results are static and do not reflect the constantly expanding knowledge in the field. In order for biomedical text mining to become an indispensable tool used by researchers, this problem must be addressed. To this end, we present PubRunner, a framework for regularly running text mining tools on the latest publications. PubRunner is lightweight, simple to use, and can be integrated with an existing text mining tool. The workflow involves downloading the latest abstracts from PubMed, executing a user-defined tool, pushing the resulting data to a public FTP or Zenodo dataset, and publicizing the location of these results on the public PubRunner website. We illustrate the use of this tool by re-running the commonly used word2vec tool on the latest PubMed abstracts to generate up-to-date word vector representations for the biomedical domain. This shows a proof of concept that we hope will encourage text mining developers to build tools that truly will aid biologists in exploring the latest publications.

Using the Women's Community Education Approach to Deliver Community Employment Training: A Case Study from Longford Women's Link

ERIC Educational Resources Information Center

Patterson, Lorne; Dowd, Kathleen

2010-01-01

The recent economic downturn and surge in unemployment has focused attention on education and training as a strategic response to Ireland's socio-economic crisis. However, that attention has been concentrated on training through statutory institutions, particularly FAS and the VECs. Longford Women's Link, a Women's Community Education centre in Co…

Detecting West Nile virus in owls and raptors by an antigen-capture assay.

PubMed

Gancz, Ady Y; Campbell, Douglas G; Barker, Ian K; Lindsay, Robbin; Hunter, Bruce

2004-12-01

We evaluated a rapid antigen-capture assay (VecTest) for detection of West Nile virus in oropharyngeal and cloacal swabs, collected at necropsy from owls (N = 93) and raptors (N = 27). Sensitivity was 93.5%-95.2% for northern owl species but <42.9% for all other species. Specificity was 100% for owls and 85.7% for raptors.

Discovery, adaptation and transcriptional activity of two tick promoters: Construction of a dual luciferase reporter system for optimization of RNA interference in Rhipicephalus (Boophilus) microplus cell lines

USDA-ARS?s Scientific Manuscript database

Dual luciferase reporter systems are valuable tools for functional genomic studies, but have not previously been developed for use in tick cell culture. We evaluated expression of available luciferase constructs in tick cell cultures derived from Rhipicephalus (Boophilus) microplus, an important vec...

Effect of Variable Emittance Coatings on the Operation of a Miniature Loop Heat Pipe

NASA Technical Reports Server (NTRS)

Douglas, Donya M.; Ku, Jentung; Ottenstein, Laura; Swanson, Theodore; Hess, Steve; Darrin, Ann

2005-01-01

Abstract. As the size of spacecraft shrink to accommodate small and more efficient instruments, smaller launch vehicles, and constellation missions, all subsystems must also be made smaller. Under NASA NFL4 03-OSS-02, Space Technology-8 (ST 8), NASA Goddard Space Flight Center and Jet Propulsion Laboratory jointly conducted a Concept Definition study to develop a miniature loop heat pipe (MLHP) thermal management system design suitable for future small spacecraft. The proposed MLHP thermal management system consists of a miniature loop heat pipe (LHP) and deployable radiators that are coated with variable emittance coatings (VECs). As part of the Phase A study and proof of the design concept, variable emittance coatings were integrated with a breadboard miniature loop heat pipe. The miniature loop heat pipe was supplied by the Jet Propulsion Laboratory (PL), while the variable emittance technology were supplied by Johns Hopkins University Applied Physics Laboratory and Sensortex, Inc. The entire system was tested under vacuum at various temperature extremes and power loads. This paper summarizes the results of this testing and shows the effect of the VEC on the operation of a miniature loop heat pipe.

Complete intracranial response to talimogene laherparepvec (T-Vec), pembrolizumab and whole brain radiotherapy in a patient with melanoma brain metastases refractory to dual checkpoint-inhibition.

PubMed

Blake, Zoë; Marks, Douglas K; Gartrell, Robyn D; Hart, Thomas; Horton, Patti; Cheng, Simon K; Taback, Bret; Horst, Basil A; Saenger, Yvonne M

2018-04-06

Immunotherapy, in particular checkpoint blockade, has changed the clinical landscape of metastatic melanoma. Nonetheless, the majority of patients will either be primary refractory or progress over follow up. Management of patients progressing on first-line immunotherapy remains challenging. Expanded treatment options with combination immunotherapy has demonstrated efficacy in patients previously unresponsive to single agent or alternative combination therapy. We describe the case of a patient with diffusely metastatic melanoma, including brain metastases, who, despite being treated with stereotactic radiosurgery and dual CTLA-4/PD-1 blockade (ipilimumab/nivolumab), developed systemic disease progression and innumerable brain metastases. This patient achieved a complete CNS response and partial systemic response with standard whole brain radiation therapy (WBRT) combined with Talimogene laherparepvec (T-Vec) and pembrolizumab. Patients who do not respond to one immunotherapy combination may respond during treatment with an alternate combination, even in the presence of multiple brain metastases. Biomarkers are needed to assist clinicians in evidence based clinical decision making after progression on first line immunotherapy to determine whether response can be achieved with second line immunotherapy.

78 FR 30399 - United States v. Anheuser-Busch InBev SA/NV, Grupo Modelo S.A.B de C.V.; Proposed Final Judgment...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-22

..., Mexico. Modelo is the third-largest brewer of beer sold in the United States. Modelo's Corona Extra brand... include Corona Light, Modelo Especial, Negra Modelo, Victoria, and Pacifico. 19. ABI currently holds a 35... such as Dogfish Head, Flying Dog, and also imported beers, the best selling of which is Modelo's Corona...

History of the Voluntary Intermodal Sealift Agreement

DTIC Science & Technology

2002-06-01

reflect executed Voluntary Enrollment Contracts (VEC) for VISA Stages I, II, and III to include basic activation procedures; DOD annual minimums for...provisions; and on-the-shelf basic agreements (such as VISA Intermodal Contingency Contracts (VICC) for Stages I, II, and III). The anticipated...insufficient Program incentives are revised annually, but the basic tenets remain in place. Activation, capacity required to commit and carrier risk clauses

Detecting West Nile Virus in Owls and Raptors by an Antigen-capture Assay

PubMed Central

Campbell, Douglas G.; Barker, Ian K.; Lindsay, Robbin; Hunter, Bruce

2004-01-01

We evaluated a rapid antigen-capture assay (VecTest) for detection of West Nile virus in oropharyngeal and cloacal swabs, collected at necropsy from owls (N = 93) and raptors (N = 27). Sensitivity was 93.5%–95.2% for northern owl species but <42.9% for all other species. Specificity was 100% for owls and 85.7% for raptors. PMID:15663862

Planning for the Future of the Adult Education Service: A Challenge for VECs

ERIC Educational Resources Information Center

Muircheartaigh, Lucas O.

2004-01-01

In this paper, the author points out that there has been a significant development of the adult education service in Ireland in recent years. However, if the service is to become part of the mainstream of Irish education, the issue of structures at all levels within the system has to be addressed. Quite frankly the present system is very…

Promoter and Cofactor Requirements for SERM-ER Activity

DTIC Science & Technology

2007-05-01

was seen in the no- digestion control or no-ligation control. We performed the same experiment using thedesigned against the intergenic region between...estrogen, and the fixed chromatin was digested with a specific restriction taining an SV40 promoter and transfected these vec- tors into hormone...Enhancer Domains and Transcriptional Activity of En- hancer Regions (A) Chromosome capture assay was per- formed after digesting fixed chromatin from

[The influence of oxygen partial pressure change and vascularization of rabbit wound through negative pressure wound therapy].

PubMed

Yang, Fan; Hu, Duan; Bai, Xiang-jun; Zhang, Kun; Li, Ren-jie; Xue, Chen-chen

2012-07-01

To investigate the effect of vacuum sealing drainage (VSD) on variation of oxygen partial pressure (PtO2) and vascularization. The 12 cases of rabbit's wound models were undergoing the VSD (vacuum group, n = 6) or conventional therapy (conventional group, n = 6). Variation of PtO2 was measured by oxygen partial pressure admeasuring apparatus, expression of hypoxia inducible factor 1α (HIF-1α) mRNA was measured by real-time fluorescent quantitative PCR, content of vascular endothelial growth factor (VEGF) was measured by ELISA after tissue homogenate in 7 days. Vascular endothelial cell (VEC) and new blood capillary (NBC) of hematoxylin-eosin slice of tissue were counted by using light microscope. Average value of PtO2 of vacuum group was significant lower than conventional group (t = -99.780 to -5.305, P < 0.01). Expression of HIF-1α (30 minutes, 1, 6, 12 hours were 3.11 ± 0.07, 3.68 ± 0.26, 4.16 ± 0.13 and 3.91 ± 0.26 respectively) and content of VEGF (30 minutes, 1, 6, 12 hours were 103.3 ± 2.4, 134.2 ± 9.0, 167.8 ± 3.8 and 232.1 ± 9.5 respectively) of vacuum group were increased after 30 minutes and significant lower than conventional group (t = 13.038 - 80.208, P < 0.01), and both of them were reduced after 24 hours (P < 0.05). Counting numbers of VEC (2.47 ± 0.45 to 4.70 ± 0.38) and NBC (1.33 ± 0.49 to 4.33 ± 0.68) of vacuum group were increased at the same time-point and significant higher than conventional group (t = -0.670 to 16.500, P < 0.05). PtO2 of wound surface could be reduced significantly by VSD. Expression of HIF-1α and content of VEGF were increased by VSD for enhancing differentiated state of VEC and construction of NBC, which were better for vascularization and wound healing.

(-)-7(S)-hydroxymatairesinol protects against tumor necrosis factor-α-mediated inflammation response in endothelial cells by blocking the MAPK/NF-κB and activating Nrf2/HO-1.

PubMed

Yang, Di; Xiao, Chen-Xi; Su, Zheng-Hua; Huang, Meng-Wei; Qin, Ming; Wu, Wei-Jun; Jia, Wan-Wan; Zhu, Yi-Zhun; Hu, Jin-Feng; Liu, Xin-Hua

2017-08-15

Endothelial inflammation is an increasingly prevalent condition in the pathogenesis of many cardiovascular diseases. (-)-7(S)-hydroxymatairesinol (7-HMR), a naturally occurring plant lignan, possesses both antioxidant and anti-cancer properties and therefore would be a good strategy to suppress tumor necrosis factor-α (TNF-α)-mediated inflammation in vascular endothelial cells (VECs). The objective of this study is to evaluate for its anti-inflammatory effect on TNF-α-stimulated VECs and underling mechanisms. The effect of the 7-HMR on suppression of TNF-α-induced inflammation mediators in VECs were determined by qRT-PCR and Western blot. MAPKs and phosphorylation of Akt, HO-1 and NF-κB p65 were examined using Western blot. Nuclear localisation of NF-κB was also examined using Western blot and immunofluorescence. Here we found that 7-HMR could suppress TNF-α-induced inflammatory mediators, such as vascularcelladhesion molecule-1, interleukin-6 and inducible nitric oxide synthase expression both in mRNA and protein levels, and concentration-dependently attenuated reactive oxidase species generation. We further identified that 7-HMR remarkably induced superoxide dismutase and heme oxygenase-1 expression associated with degradation of Kelch-like ECH-associated protein 1 (keap1) and up-regulated nuclear factor erythroid 2-related factor 2 (Nrf2). In addition, 7-HMR time- and concentration-dependently attenuated TNF-α-induced phosphorylation of extracellular signal-regulated kinase 1/2 (ERK) and Akt, but not p38, or c-Jun N-terminal kinase 1/2. Moreover, 7-HMR significantly suppressed TNF-α-mediated nuclear factor-κB (NF-κB) activation by inhibiting phosphorylation and nuclear translocation of NF-κB p65. Our results demonstrated that 7-HMR inhibited TNF-α-stimulated endothelial inflammation, at least in part, through inhibition of NF-κB activation and upregulation of Nrf2-antioxidant response element signaling pathway, suggesting 7-HMR might be used as a promising vascular protective drug. Copyright © 2017. Published by Elsevier GmbH.

Predicting Student Grade Based on Free-Style Comments Using Word2Vec and ANN by Considering Prediction Results Obtained in Consecutive Lessons

ERIC Educational Resources Information Center

Luo, Jingyi; Sorour, Shaymaa E.; Goda, Kazumasa; Mine, Tsunenori

2015-01-01

Continuously tracking students during a whole semester plays a vital role to enable a teacher to grasp their learning situation, attitude and motivation. It also helps to give correct assessment and useful feedback to them. To this end, we ask students to write their comments just after each lesson, because student comments reflect their learning…

Sc–Zr–Nb–Rh–Pd and Sc–Zr–Nb–Ta–Rh–Pd High-Entropy Alloy Superconductors on a CsCl-Type Lattice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stolze, Karoline; Tao, Jing; von Rohr, Fabian O.

We have synthesized previously unreported High-Entropy Alloys (HEAs) in the pentanary (ScZrNb) 1-x[RhPd] x and hexanary (ScZrNbTa) 1-x[RhPd] x systems. The materials have CsCl-type structures and mixed site occupancies. Both HEAs are type-II superconductors with strongly varying critical temperatures (T cs) depending on the valence electron count (VEC); the T cs increase monotonically with decreasing VEC within each series, and do not follow the trends seen for either crystalline or amorphous transition metal superconductors. The (ScZrNb) 0.65[RhPd] 0.35 HEA with the highest T c, ~9.3 K, also exhibits the largest µ 0H c2(0) = 10.7 T. The pentanary and hexanarymore » HEAs have higher superconducting transition tempera-tures than their simple binary intermetallic relatives with the CsCl-type structure and a surprisingly ductile mechanical behavior. The presence of niobium, even at the 20% level, has a positive impact on the T c. Nevertheless, niobium-free (ScZr) 0.50[RhPd] 0.50, as mother-compound of both superconducting HEAs found here, is itself superconducting, proving that superconductivity is an intrinsic feature of the bulk material.« less

Electronic structure and the origin of the Dzyaloshinskii-Moriya interaction in MnSi

DOE PAGES

Satpathy, S.; Shanavas, K. V.

2016-05-02

Here, the metallic helimagnet MnSi has been found to exhibit skyrmionic spin textures when subjected to magnetic fields at low temperatures. The Dzyaloshinskii-Moriya (DM) interaction plays a key role in stabilizing the skyrmion state. With the help of first-principles calculations, crystal field theory and a tight-binding model we study the electronic structure and the origin of the DM interaction in the B20 phase of MnSi. The strength ofmore » $$\\vec{D}$$ parameter is determined by the magnitude of the spin-orbit interaction and the degree of orbital mixing, induced by the symmetry-breaking distortions in the B20 phase. We find that, strong coupling between Mn-$d$ and Si-$p$ states lead to a mixed valence ground state $$|d^{7-x}p^{2+x}\\rangle$$ configuration. The experimental magnetic moment of $$0.4~\\mu_B$$ is consistent with the Coulomb-corrected DFT+$U$ calculations, which redistributes electrons between the majority and minority spin channels. We derive the magnetic interaction parameters $J$ and $$\\vec{D}$$ for Mn-Si-Mn superexchange paths using Moriya's theory assuming the interaction to be mediated by $$e_g$$ electrons near the Fermi level. Finally, using parameters from our calculations, we get reasonable agreement with the observations.« less

Sc–Zr–Nb–Rh–Pd and Sc–Zr–Nb–Ta–Rh–Pd High-Entropy Alloy Superconductors on a CsCl-Type Lattice

DOE PAGES

Stolze, Karoline; Tao, Jing; von Rohr, Fabian O.; ...

2018-01-17

We have synthesized previously unreported High-Entropy Alloys (HEAs) in the pentanary (ScZrNb) 1-x[RhPd] x and hexanary (ScZrNbTa) 1-x[RhPd] x systems. The materials have CsCl-type structures and mixed site occupancies. Both HEAs are type-II superconductors with strongly varying critical temperatures (T cs) depending on the valence electron count (VEC); the T cs increase monotonically with decreasing VEC within each series, and do not follow the trends seen for either crystalline or amorphous transition metal superconductors. The (ScZrNb) 0.65[RhPd] 0.35 HEA with the highest T c, ~9.3 K, also exhibits the largest µ 0H c2(0) = 10.7 T. The pentanary and hexanarymore » HEAs have higher superconducting transition tempera-tures than their simple binary intermetallic relatives with the CsCl-type structure and a surprisingly ductile mechanical behavior. The presence of niobium, even at the 20% level, has a positive impact on the T c. Nevertheless, niobium-free (ScZr) 0.50[RhPd] 0.50, as mother-compound of both superconducting HEAs found here, is itself superconducting, proving that superconductivity is an intrinsic feature of the bulk material.« less

Current distribution and ac susceptibility response of a thin superconducting disc in an axial field: a theoretical approach

NASA Astrophysics Data System (ADS)

Aruna, S. A.; Zhang, P.; Lin, F. Y.; Ding, S. Y.; Yao, X. X.

2000-04-01

Within the framework of the thermally activated process of the flux line or flux line bundles, and by time integration of the 1D equation of motion of the circulating current density icons/Journals/Common/vecJ" ALT="vecJ" ALIGN="TOP"/> (icons/Journals/Common/rho" ALT="rho" ALIGN="TOP"/> ,t ), which is suitable for thin superconducting films (R >>d ,icons/Journals/Common/le" ALT="le" ALIGN="TOP"/> icons/Journals/Common/lambda" ALT="lambda" ALIGN="TOP"/> ), we present numerical calculations of the current profiles, magnetization hysteresis loops and ac susceptibility icons/Journals/Common/chi" ALT="chi" ALIGN="TOP"/> n = icons/Journals/Common/chi" ALT="chi" ALIGN="TOP"/> ´n +iicons/Journals/Common/chi" ALT="chi" ALIGN="TOP"/> ´´n for n = 1, 3 and 5 of a thin disc immersed in an axial time-dependent external magnetic field Ba (t ) = Bdc +Bac cos(2icons/Journals/Common/pi" ALT="pi" ALIGN="TOP"/> icons/Journals/Common/nu" ALT="nu" ALIGN="TOP"/> t ). Our calculated results are compared with those of the critical state model (CSM) and found to prove the approximate validity of the CSM below the irreversibility field. The differences between our computed results and those of the CSM are also discussed.

Virtual Solar Energy Center: A Case Study of the Use of Advanced Visualization Techniques for the Comprehension of Complex Engineering Products and Processes

NASA Astrophysics Data System (ADS)

Ritter, Kenneth August, III

Industry has a continuing need to train its workforce on recent engineering developments, but many engineering products and processes are hard to explain because of limitations of size, visibility, time scale, cost, and safety. The product or process might be difficult to see because it is either very large or very small, because it is enclosed within an opaque container, or because it happens very fast or very slowly. Some engineering products and processes are also costly or unsafe to use for training purposes, and sometimes the domain expert is not physically available at the training location. All these limitations can potentially be addressed using advanced visualization techniques such as virtual reality. This dissertation describes the development of an immersive virtual reality application using the Six Sigma DMADV process to explain the main equipment and processes used in a concentrating solar power plant. The virtual solar energy center (VEC) application was initially developed and tested in a Cave Automatic Virtual Environment (CAVE) during 2013 and 2014. The software programs used for development were SolidWorks, 3ds Max Design, and Unity 3D. Current hardware and software technologies that could complement this research were analyzed. The NVIDA GRID Visual Computing Appliance (VCA) was chosen as the rendering solution for animating complex CAD models in this application. The MiddleVR software toolkit was selected as the toolkit for VR interactions and CAVE display. A non-immersive 3D version of the VEC application was tested and shown to be an effective training tool in late 2015. An immersive networked version of the VEC allows the user to receive live instruction from a trainer being projected via depth camera imagery from a remote location. Four comparative analysis studies were performed. These studies used the average normalized gain from pre-test scores to determine the effectiveness of the various training methods. With the DMADV approach, solutions were identified and verified during each iteration of the development, which saved valuable time and resulted in better results being achieved in each revision of the application, with the final version having 88% positive responses and same effectiveness as other methods assessed.

The effect of novel magnetic nanoparticles on vascular endothelial cell function in vitro and in vivo.

PubMed

Su, Le; Han, Lei; Ge, Fei; Zhang, Shang Li; Zhang, Yun; Zhao, Bao Xiang; Zhao, Jing; Miao, Jun Ying

2012-10-15

Manufactured nanoparticles are currently used for many fields. However, their potential toxicity provides a growing concern for human health. In our previous study, we prepared novel magnetic nanoparticles (MNPs), which could effectively remove heavy metal ions and cationic dyes from aqueous solution. To understand its biocompatibility, we investigated the effect of the nanoparticles on the function of vascular endothelial cells. The results showed that the nanoparticles were taken up by human umbilical vein endothelial cells (HUVECs) and could inhibit cell proliferation at 400 μg/ml. An increase in nitric oxide (NO) production and endothelial nitric oxide synthase (eNOS) activity were induced, which companied with the decrease in caveolin-1 level. The endothelium in the aortic root was damaged and the NO level in serum was elevated after treated mice with 20mg/kg nanoparticles for 3 days, but it was integrated after treated with 5mg/kg nanoparticles. Meanwhile, an increase in eNOS activity and decrease in caveolin-1 level were induced in the endothelium. The data suggested that the low concentration of nanoparticles could not affect the function and viability of VECs. The high concentration of nanoparticles could inhibit VEC proliferation through elevation of the eNOS activity and NO production and thus present toxicity. Copyright © 2012 Elsevier B.V. All rights reserved.

Design of large vacuum chamber for VEC superconducting cyclotron beam line switching magnet

NASA Astrophysics Data System (ADS)

Bhattacharya, Sumantra; Nandi, Chinmoy; Gayen, Subhasis; Roy, Suvadeep; Mishra, Santosh Kumar; Ramrao Bajirao, Sanjay; Pal, Gautam; Mallik, C.

2012-11-01

VEC K500 superconducting cyclotron will be used to accelerate heavy ion. The accelerated beam will be transported to different beam halls by using large switching magnets. The vacuum chamber for the switching magnet is around 1000 mm long. It has a height of 85 mm and width varying from 100 mm to 360 mm. The material for the chamber has been chosen as SS304.The material for the vacuum chamber for the switching magnet has been chosen as SS304. Design of the vessel was done as per ASME Boiler and Pressure Vessel Code, Section VIII, Division 1. It was observed that primary stress values exceed the allowable limit. Since, the magnet was already designed with a fixed pole gap; increase of the vacuum chamber plate thickness restricts the space for beam transport. Design was optimized using stress analysis software ANSYS. Analysis was started using plate thickness of 4 mm. The stress was found higher than the allowable level. The analysis was repeated by increasing plate thickness to 6 mm, resulting in the reduction of stress level below the allowable level. In order to reduce the stress concentration due to sharp bend, chamfering was done at the corner, where the stress level was higher. The thickness of the plate at the corner was increased from 6 mm to 10 mm. These measures resulted in reduction of localized stress.

Live imaging reveals a conserved role of fatty acid β-oxidation in early lymphatic development in zebrafish.

PubMed

Zecchin, Annalisa; Wong, Brian W; Tembuyser, Bieke; Souffreau, Joris; Van Nuffelen, An; Wyns, Sabine; Vinckier, Stefan; Carmeliet, Peter; Dewerchin, Mieke

2018-06-18

During embryonic development, lymphatic endothelial cells (LECs) differentiate from venous endothelial cells (VECs), a process that is tightly regulated by several genetic signals. While the aquatic zebrafish model is regularly used for studying lymphangiogenesis and offers the unique advantage of time-lapse video-imaging of lymphatic development, some aspects of lymphatic development in this model differ from those in the mouse. It therefore remained to be determined whether fatty acid β-oxidation (FAO), which we showed to regulate lymphatic formation in the mouse, also co-determines lymphatic development in this aquatic model. Here, we took advantage of the power of the zebrafish embryo model to visualize the earliest steps of lymphatic development through time-lapse video-imaging. By targeting zebrafish isoforms of carnitine palmitoyltransferase 1a (cpt1a), a rate controlling enzyme of FAO, with multiple morpholinos, we demonstrate that reducing CPT1A levels and FAO flux during zebrafish development impairs lymphangiogenic secondary sprouting, the initiation of lymphatic development in the zebrafish trunk, and the formation of the first lymphatic structures. These findings not only show evolutionary conservation of the importance of FAO for lymphatic development, but also suggest a role for FAO in co-regulating the process of VEC-to-LEC differentiation in zebrafish in vivo. Copyright © 2018 Elsevier Inc. All rights reserved.

Targeting tissue factor-expressing tumor angiogenesis and tumors with EF24 conjugated to factor VIIa.

PubMed

Shoji, Mamoru; Sun, Aiming; Kisiel, Walter; Lu, Yang J; Shim, Hyunsuk; McCarey, Bernard E; Nichols, Christopher; Parker, Ernest T; Pohl, Jan; Mosley, Cara A; Alizadeh, Aaron R; Liotta, Dennis C; Snyder, James P

2008-04-01

Tissue factor (TF) is aberrantly expressed on tumor vascular endothelial cells (VECs) and on cancer cells in many malignant tumors, but not on normal VECs, making it a promising target for cancer therapy. As a transmembrane receptor for coagulation factor VIIa (fVIIa), TF forms a high-affinity complex with its cognate ligand, which is subsequently internalized through receptor-mediated endocytosis. Accordingly, we developed a method for selectively delivering EF24, a potent synthetic curcumin analog, to TF-expressing tumor vasculature and tumors using fVIIa as a drug carrier. EF24 was chemically conjugated to fVIIa through a tripeptide-chloromethyl ketone. After binding to TF-expressing targets by fVIIa, EF24 will be endocytosed along with the drug carrier and will exert its cytotoxicity. Our results showed that the conjugate inhibits vascular endothelial growth factor-induced angiogenesis in a rabbit cornea model and in a Matrigel model in athymic nude mice. The conjugate-induced apoptosis in tumor cells and significantly reduced tumor size in human breast cancer xenografts in athymic nude mice as compared with the unconjugated EF24. By conjugating potent drugs to fVIIa, this targeted drug delivery system has the potential to enhance therapeutic efficacy, while reducing toxic side effects. It may also prove to be useful for treating drug-resistant tumors and micro-metastases in addition to primary tumors.

L'effet Hall Quantique

NASA Astrophysics Data System (ADS)

Samson, Thomas

Nous proposons une methode permettant d'obtenir une expression pour la conductivite de Hall de structures electroniques bidimensionnelles et nous examinons celle -ci a la limite d'une temperature nulle dans le but de verifier l'effet Hall quantique. Nous allons nous interesser essentiellement a l'effet Hall quantique entier et aux effets fractionnaires inferieurs a un. Le systeme considere est forme d'un gaz d'electrons en interaction faible avec les impuretes de l'echantillon. Le modele du gaz d'electrons consiste en un gaz bidimensionnel d'electrons sans spin expose perpendiculairement a un champ magnetique uniforme. Ce dernier est decrit par le potentiel vecteur vec{rm A} defini dans la jauge de Dingle ou jauge symetrique. Conformement au formalisme de la seconde quantification, l'hamiltonien de ce gaz est represente dans la base des etats a un-corps de Dingle |n,m> et exprime ainsi en terme des operateurs de creation et d'annihilation correspondants a_sp{ rm n m}{dag} et a _{rm n m}. Nous supposons de plus que les electrons du niveau fondamental de Dingle interagissent entre eux via le potentiel coulombien. La methode utilisee fait appel a une equation mai tresse a N-corps, de nature quantique et statistique, et verifiant le second principe de la thermodynamique. A partir de celle-ci, nous obtenons un systeme d'equations differentielles appele hierarchie d'equations quantique dont la resolution nous permet de determiner une equation a un-corps, dite de Boltzmann quantique, et dictant l'evolution de la moyenne statistique de l'operateur non-diagonal a _sp{rm n m}{dag } a_{rm n}, _{rm m}, sous l'action du champ electrique applique vec{rm E}(t). C'est sa solution Tr(p(t) a _sp{rm n m}{dag} a_{rm n},_ {rm m}), qui definit la relation de convolution entre la densite courant de Hall vec{rm J}_{rm H }(t) et le champ electrique vec {rm E}(t) dont la transformee de Laplace-Fourier du noyau nous fournit l'expression de la conductivite de Hall desiree. Pour une valeur de facteur d'occupation (nombre d'electrons/degenerescence des etats de Dingle) superieure a un, c'est-a-dire en absence d'interaction electron-electron, il nous sera facile d'evaluer cette conductivite a la limite d'une temperature nulle et de demontrer qu'elle tend vers l'une des valeurs quantiques qe^2/h conformement a l'effet Hall quantique entier. Cependant, pour une valeur du facteur d'occupation inferieure a un, c'est-a-dire en presence d'interaction electron-electron, nous ne pourrons evaluer cette limite et obtenir les resultats escomptes a cause de l'impossibilite de determiner l'un des termes impliques. Neanmoins, ce dernier etant de nature statistique, il pourra etre aisement mis en fonction du propagateur du gaz d'electrons dont on doit maintenant determiner une expression en regime effet Hall quantique fractionnaire. Apres avoir demontre l'impuissance de la theorie des perturbations, basee sur le theoreme de Wick et la technique des diagrammes de Feynman, a accomplir cette tache correctement, nous proposons une seconde methode. Celle -ci fait appel au formalisme de l'integrale fonctionnelle et a l'utilisation d'une transformation de Hubbard-Stratonovich generalisee permettant de substituer a l'interaction a deux-corps une interaction effective a un-corps. L'expression finale obtenue bien que non completement resolue, devrait pouvoir etre estimee par une bonne approximation analytique ou au pire numeriquement.

Reinforced Concrete Wall Form Design Program

DTIC Science & Technology

1992-08-01

criteria is an absolute limit. You have the choice of 1/8 or 1/16 of an inch total deflection in a span. Once these limits are set here, then they are...Calls GET-INFO-TEXT - Calls ZERO -PLY - If the response to GET-INFO-TEXT is "Values retrieved by computer", then the following procedures are executed...like to enter their own values. ZERO -PLY - Re-initializes all PLY-VEC values to"?". GET-PLY-CLASS - Retrieves from the user the grade of plyform to be

Study of the Local Horizon. (Spanish Title: Estudio del Horizonte Local.) Estudo do Horizonte Local

NASA Astrophysics Data System (ADS)

Ros, Rosa M.

2009-12-01

The study of the horizon is fundamental to easy the first observations of the students at any education center. A simple model, to be developed in each center, allows to easy the study and comprehension of the rudiments of astronomy. The constructed model is presented in turn as a simple equatorial clock, other models (horizontal and vertical) may be constructed starting from it. El estudio del horizonte es fundamental para poder facilitar las primeras observaciones de los alumnos en un centro educativo. Un simple modelo, que debe realizarse para cada centro, nos permite facilitar el estudio y la comprensión de los primeros rudimentos astronómicos. El modelo construido se presenta a su vez como un sencillo modelo de reloj ecuatorial y a partir de él se pueden construir otros modelos (horizontal y vertical). O estudo do horizonte é fundamental para facilitar as primeiras observações dos alunos num centro educativo. Um modelo simples, que deve ser feito para cada centro, permite facilitar o estudo e a compreensão dos primeiros rudimentos astronômicos. O modelo construído apresenta-se, por sua vez, como um modelo simples de relógio equatorial e a partir dele pode-se construir outros modelos (horizontal e vertical)

Model determination in a case of heterogeneity of variance using sampling techniques.

PubMed

Varona, L; Moreno, C; Garcia-Cortes, L A; Altarriba, J

1997-01-12

A sampling determination procedure has been described in a case of heterogeneity of variance. The procedure makes use of the predictive distributions of each data given the rest of the data and the structure of the assumed model. The computation of these predictive distributions is carried out using a Gibbs Sampling procedure. The final criterion to compare between models is the Mean Square Error between the expectation of predictive distributions and real data. The procedure has been applied to a data set of weight at 210 days in the Spanish Pirenaica beef cattle breed. Three proposed models have been compared: (a) Single Trait Animal Model; (b) Heterogeneous Variance Animal Model; and (c) Multiple Trait Animal Model. After applying the procedure, the most adjusted model was the Heterogeneous Variance Animal Model. This result is probably due to a compromise between the complexity of the model and the amount of available information. The estimated heritabilities under the preferred model have been 0.489 ± 0.076 for males and 0.331 ± 0.082 for females. RESUMEN: Contraste de modelos en un caso de heterogeneidad de varianzas usando métodos de muestreo Se ha descrito un método de contraste de modelos mediante técnicas de muestreo en un caso de heterogeneidad de varianza entre sexos. El procedimiento utiliza las distribucviones predictivas de cada dato, dado el resto de datos y la estructura del modelo. El criterio para coparar modelos es el error cuadrático medio entre la esperanza de las distribuciones predictivas y los datos reales. El procedimiento se ha aplicado en datos de peso a los 210 días en la raza bovina Pirenaica. Se han propuesto tres posibles modelos: (a) Modelo Animal Unicaracter; (b) Modelo Animal con Varianzas Heterogéneas; (c) Modelo Animal Multicaracter. El modelo mejor ajustado fue el Modelo Animal con Varianzas Heterogéneas. Este resultado es probablemente debido a un compromiso entre la complejidad del modelo y la cantidad de datos disponibles. Las heredabilidades estimadas bajo el modelo preferido han sido 0,489 ± 0,076 en los machos y 0,331 ± 0,082 en las hembras. 1997 Blackwell Verlag GmbH.

Testing neoclassical and turbulent effects on poloidal rotation in the core of DIII-D

DOE PAGES

Chrystal, Colin; Burrell, Keith H.; Grierson, Brian A.; ...

2014-07-09

Experimental tests of ion poloidal rotation theories have been performed on DIII-D using a novel impurity poloidal rotation diagnostic. These tests show significant disagreements with theoretical predictions in various conditions, including L-mode plasmas with internal transport barriers (ITB), H-mode plasmas, and QH-mode plasmas. The theories tested include standard neoclassical theory, turbulence driven Reynolds stress, and fast-ion friction on the thermal ions. Poloidal rotation is observed to spin up at the formation of an ITB and makes a significant contribution to the measurement of themore » $$\\vec{E}$$ × $$\\vec{B}$$ shear that forms the ITB. In ITB cases, neoclassical theory agrees quantitatively with the experimental measurements only in the steep gradient region. Significant quantitative disagreement with neoclassical predictions is seen in the cores of ITB, QH-, and H-mode plasmas, demonstrating that neoclassical theory is an incomplete description of poloidal rotation. The addition of turbulence driven Reynolds stress does not remedy this disagreement; linear stability calculations and Doppler backscattering measurements show that disagreement increases as turbulence levels decline. Furthermore, the effect of fast-ion friction, by itself, does not lead to improved agreement; in QH-mode plasmas, neoclassical predictions are closest to experimental results in plasmas with the largest fast ion friction. Finally, predictions from a new model that combines all three effects show somewhat better agreement in the H-mode case, but discrepancies well outside the experimental error bars remain.« less

Vaginal ecosystem modeling of growth patterns of anaerobic bacteria in microaerophilic conditions.

PubMed

Medina-Colorado, Audrie A; Vincent, Kathleen L; Miller, Aaron L; Maxwell, Carrie A; Dawson, Lauren N; Olive, Trevelyn; Kozlova, Elena V; Baum, Marc M; Pyles, Richard B

2017-06-01

The human vagina constitutes a complex ecosystem created through relationships established between host mucosa and bacterial communities. In this ecosystem, classically defined bacterial aerobes and anaerobes thrive as communities in the microaerophilic environment. Levels of CO 2 and O 2 present in the vaginal lumen are impacted by both the ecosystem's physiology and the behavior and health of the human host. Study of such complex relationships requires controlled and reproducible causational approaches that are not possible in the human host that, until recently, was the only place these bacterial communities thrived. To address this need we have utilized our ex vivo human vaginal mucosa culture system to support controlled, reproducible colonization by vaginal bacterial communities (VBC) collected from healthy, asymptomatic donors. Parallel vaginal epithelial cells (VEC)-VBC co-cultures were exposed to two different atmospheric conditions to study the impact of CO 2 concentrations upon the anaerobic bacteria associated with dysbiosis and inflammation. Our data suggest that in the context of transplanted VBC, increased CO 2 favored specific lactobacilli species defined as microaerophiles when grown as monocultures. In preliminary studies, the observed community changes also led to shifts in host VEC phenotypes with significant changes in the host transcriptome, including altered expression of select molecular transporter genes. These findings support the need for additional study of the environmental changes associated with behavior and health upon the symbiotic and adversarial relationships that are formed in microbial communities present in the human vaginal ecosystem. Copyright © 2017 Elsevier Ltd. All rights reserved.

Study of transionospheric signal scintillation: Quasi- particle approach

NASA Astrophysics Data System (ADS)

Lyle, Ruthie D.

1998-07-01

A quasi-particle approach is applied to study amplitude scintillation of transionospheric signals caused by Bottomside Sinusoidal (BSS) irregularities. The quasi- particle method exploits wave-particle duality, viewing the wave as a distribution of quasi-particles. This is accomplished by transforming the autocorrelation of the wave function into a Wigner distribution function, which serves as a distribution of quasi-particles in the (/vec r,/ /vec k) phase space. The quasi-particle distribution at any instant of time represents the instantaneous state of the wave. Scattering of the signal by the ionospheric irregularities is equivalent to the evolution of the quasi-particle distribution, due to the collision of the quasi-particles with objects arising from the presence of the BSS irregularities. Subsequently, the perturbed quasi-particle distribution facilitates the computation of average space time propagation properties of the wave. Thus, the scintillation index S4 is determined. Incorporation of essential BSS features in the analysis is accomplished by analytically modeling the power spectrum of the BSS irregularities measured in-situ by the low orbiting Atmosphere-E (AE - E) Satellite. The effect of BSS irregularities on transionospheric signals has been studied. The numerical results agree well with multi-satellite scintillation observations made at Huancayo Peru in close time correspondence with BSS irregularities observed by the AE - E satellite over a few nights (December 8-11, 1979). During this period, the severity of the scintillation varied from moderate to intense, S4 = 0.1-0.8.

Translocation of cell-penetrating peptides into Candida fungal pathogens.

PubMed

Gong, Zifan; Karlsson, Amy J

2017-09-01

Cell-penetrating peptides (CPPs) are small peptides capable of crossing cellular membranes while carrying molecular cargo. Although they have been widely studied for their ability to translocate nucleic acids, small molecules, and proteins into mammalian cells, studies of their interaction with fungal cells are limited. In this work, we evaluated the translocation of eleven fluorescently labeled peptides into the important human fungal pathogens Candida albicans and C. glabrata and explored the mechanisms of translocation. Seven of these peptides (cecropin B, penetratin, pVEC, MAP, SynB, (KFF) 3 K, and MPG) exhibited substantial translocation (>80% of cells) into both species in a concentration-dependent manner, and an additional peptide (TP-10) exhibiting strong translocation into only C. glabrata. Vacuoles were involved in translocation and intracellular trafficking of the peptides in the fungal cells and, for some peptides, escape from the vacuoles and localization in the cytosol were correlated to toxicity toward the fungal cells. Endocytosis was involved in the translocation of cecropin B, MAP, SynB, MPG, (KFF) 3 K, and TP-10, and cecropin B, penetratin, pVEC, and MAP caused membrane permeabilization during translocation. These results indicate the involvement of multiple translocation mechanisms for some CPPs. Although high levels of translocation were typically associated with toxicity of the peptides toward the fungal cells, SynB was translocated efficiently into Candida cells at concentrations that led to minimal toxicity. Our work highlights the potential of CPPs in delivering antifungal molecules and other bioactive cargo to Candida pathogens. © 2017 The Protein Society.

A Phase-Based Approach to Satellite Constellation Analysis and Design

DTIC Science & Technology

1991-01-01

and 4p is a phase angle representing true anomaly, as measured from the line of nodes. For a spherical earth, the orbital parameters are related...Var Outdat : Arrayll..2,1..90] of Real; J Output data for cost versus optimization parameter I F : text; { Output file Y, DY : Vec2; Y is a point on...InitGraph(Gd, Gm,’graph’); Assign(f,’c:\\matlab\\ OutDat ’); Rewrite (f); 129 7 o / With Common do with Target do With LoopParm do With Constellation do

Factors associated with the risk of West Nile Virus among crows in New York State

PubMed Central

DeCarlo, C. H.; Clark, A. B.; McGowan, K. J.; Ziegler, P. E.; Glaser, A. L.; Szonyi, B.; Mohammed, H. O.

2010-01-01

West Nile virus (WNV) is transmitted between avian hosts in enzootic cycles by a mosquito vector. The virus has significant disease effects on humans and equines when it bridges into an epizootic cycle. Since the initial epidemic of WNV in 1999, perennial outbreaks in New York State suggest the local establishment of natural foci with perpetuation of the virus among susceptible hosts rather than reintroduction of the virus. The factors that play a role in the perpetuation of the virus are not fully understood. American crows (Corvus brachyrhynchos) are known to be highly susceptible to infection with the virus. We investigate the factors that put crows at risk of infection in Tompkins County, New York during the period of 2000 through 2008 in a case-control study. Cases were crow carcasses that were found dead and tested positive for WNV using real time reverse transcription (RT-PCR) or VecTestR. Data on putative risk factors were collected and assessed for significance of association with the presence of WNV using logistic regression analysis to evaluate the significance of each factor while simultaneously controlling for the effect of others. The risk of a crow carcass testing WNV positive varied with age, season of the year, and ecological area where the carcass was found. Crows that were more than one year old were 4 times more likely to be WNV positive in comparison to birds that were less than one year of age. It was three times more likely to find WNV positive carcasses in residential areas in comparison to rural areas. The risk of testing WNV positive did not vary by sex of the crow carcasses. PMID:20707862

Construction of PR39 recombinant AAV under control of the HRE promoter and the effect of recombinant AAV on gene therapy of ischemic heart disease

PubMed Central

SUN, LIJUN; HAO, YUEWEN; NIE, XIAOWEI; ZHANG, XUEXIN; YANG, GUANGXIAO; WANG, QUANYING

2012-01-01

The objective of this study was to investigate the effect of the PR39 recombinant adeno-associated virus (AAV) controlled by the hypoxia-responsive element (HRE) on gene therapy of ischemic heart disease. The minimal HRE was artificially synthesized and the AAV vector controlled by HRE was introduced with NT4-TAT-His-PR39 to investigate the expression of AAV-PR39 in hypoxic vascular endothelial cells (VEC) of human umbilical vein (CRL-1730 cell line) and the angiogenesis-promoting effect in pigs with acute myocardial infraction (AMI). The minimal HRE/CMV was designed and artificially synthesized using the PCR method and cloned with the T vector cloning method. The pSS-HRE-CMV-NT4-6His-PR39-PolyA-AAV plasmid was constructed. Using the calcium phosphate precipitation method, HEK-293 cells were co-transfected with three plasmids to produce the recombinant virus. An equal volume of pSS-HRE-CMV-NT4-6His-PR39-PolyAAAV and enterovirus (EV, blank virus) was transfected into CRL-1730 cell lines, respectively. The immunohistochemical method was used to assay the expression of 6xHis in CRL-1730 cell lines and the expression of PR39 under hypoxia. Eighteen AMI miniature pigs were randomized into the experimental group (HRE-AAV-PR39 group), control group 1 (physical saline group) and control group 2 (EV group). The area of ischemia was assessed with conventional MRI and myocardium perfusion MRI. Pigs were sacrificed at preset time-points to obtain samples of ischemic myocardium. Morphological and pathological data were collected. According to data in the literature and databases, the minimal HRE was designed and synthesized with the PCR method. A large number of HREs were connected to modified pSSHGAAV (pSSV9int-/XbaI) vector followed by insertion of the NT4-6His-PR39 gene segment and, thus, the recombinant plasmid pSS-HRE-CMV-NT4-6His-PR39-PolyA-AAV was successfully constructed. The expression of 6xHis in CRL-1730 cells under the regulation of HRE was assayed using the immunohistochemical method and results showed that the expression was positive in the experimental group. Myocardium perfusion MRI displayed that the infracted area significantly decreased under the action of pSS-HRE-CMV-NT4-PR39-PolyA-AAV. The artificial minimal HRE in CRL-1730 cells effectively and rapidly regulates the expression of the downstream gene NT4-TAT-His-PR39 of the CMV promoter. Recombinant pSS-HRE-CMV-NT4-PR39-Poly-AAAV promotes neoangiogenesis in the ischemic area, reduces the area of infarction and improves heart function. PMID:23226731

Construction of PR39 recombinant AAV under control of the HRE promoter and the effect of recombinant AAV on gene therapy of ischemic heart disease.

PubMed

Sun, Lijun; Hao, Yuewen; Nie, Xiaowei; Zhang, Xuexin; Yang, Guangxiao; Wang, Quanying

2012-11-01

The objective of this study was to investigate the effect of the PR39 recombinant adeno-associated virus (AAV) controlled by the hypoxia-responsive element (HRE) on gene therapy of ischemic heart disease. The minimal HRE was artificially synthesized and the AAV vector controlled by HRE was introduced with NT4-TAT-His-PR39 to investigate the expression of AAV-PR39 in hypoxic vascular endothelial cells (VEC) of human umbilical vein (CRL-1730 cell line) and the angiogenesis-promoting effect in pigs with acute myocardial infraction (AMI). The minimal HRE/CMV was designed and artificially synthesized using the PCR method and cloned with the T vector cloning method. The pSS-HRE-CMV-NT4-6His-PR39-PolyA-AAV plasmid was constructed. Using the calcium phosphate precipitation method, HEK-293 cells were co-transfected with three plasmids to produce the recombinant virus. An equal volume of pSS-HRE-CMV-NT4-6His-PR39-PolyAAAV and enterovirus (EV, blank virus) was transfected into CRL-1730 cell lines, respectively. The immunohistochemical method was used to assay the expression of 6xHis in CRL-1730 cell lines and the expression of PR39 under hypoxia. Eighteen AMI miniature pigs were randomized into the experimental group (HRE-AAV-PR39 group), control group 1 (physical saline group) and control group 2 (EV group). The area of ischemia was assessed with conventional MRI and myocardium perfusion MRI. Pigs were sacrificed at preset time-points to obtain samples of ischemic myocardium. Morphological and pathological data were collected. According to data in the literature and databases, the minimal HRE was designed and synthesized with the PCR method. A large number of HREs were connected to modified pSSHGAAV (pSSV9int-/XbaI) vector followed by insertion of the NT4-6His-PR39 gene segment and, thus, the recombinant plasmid pSS-HRE-CMV-NT4-6His-PR39-PolyA-AAV was successfully constructed. The expression of 6xHis in CRL-1730 cells under the regulation of HRE was assayed using the immunohistochemical method and results showed that the expression was positive in the experimental group. Myocardium perfusion MRI displayed that the infracted area significantly decreased under the action of pSS-HRE-CMV-NT4-PR39-PolyA-AAV. The artificial minimal HRE in CRL-1730 cells effectively and rapidly regulates the expression of the downstream gene NT4-TAT-His-PR39 of the CMV promoter. Recombinant pSS-HRE-CMV-NT4-PR39-Poly-AAAV promotes neoangiogenesis in the ischemic area, reduces the area of infarction and improves heart function.

Matrix Metalloproteinase-9 Is a Predictive Factor for Systematic Hypertension and Heart Dysfunction in Patients with Obstructive Sleep Apnea Syndrome

PubMed Central

Wang, Shuhui; Li, Shisheng; Wang, Bin; Liu, Jiajia

2018-01-01

Patients with obstructive sleep apnea syndrome (OSAS) showed higher prevalence in cardiovascular diseases due to aberrant hypoxia and oxidative stress. However, not all OSAS patients end up with cardiovascular disorders, and identification of novel biomarker will be invaluable for differentiating patients at risk. Here we tested the serum matrix metalloproteinase-9 (MMP-9) levels in 47 untreated OSAS patients and found that the MMP-9 level was positively correlated with severity of OSAS, which was consistent with hypoxia degree and duration. Besides, the MMP-9 level was higher in patients complicated with systematic hypertension (P < 0.001). Furthermore, we selected those OSAS patients without any cardiovascular dysfunction (n = 35) and followed up for up to five years. By the end of follow-up, 12 patients had hypertension onset and 3 patients had left ventricular hypertrophy. By analyzing the clinical outcomes with MMP-9 expression, we demonstrated that high serum MMP-9 in OSAS patients was a risk factor for occurrence of cardiovascular diseases. In addition, we cultured the vascular endothelial cells (VEC) from rat aorta in hypoxia condition to investigate whether MMP-9 was elevated due to hypoxia in OSAS patients. Cellular results revealed that the expression, secretion, and activity of MMP-9 were all upregulated by hypoxia and can cleave the beta2-adrenergic receptor (β2AR) on VEC surface. Our results not only determined MMP-9 as a risk factor for cardiovascular diseases in OSAS patients, but also showed the possible involvement of hypoxia-MMP-9-β2AR signaling axis. PMID:29693002

Creation of an acellular vaginal matrix for potential vaginal augmentation and cloacal repair.

PubMed

Greco, K V; Jones, L G; Obiri-Yeboa, I; Ansari, T

2018-05-21

our aim was to use porcine vagina to create a vaginal matrix and test its cellular biocompatibility. vagina was harvested from pigs and de-cellularised (DC) using a combination of detergents (Triton x-100 and sodium deoxycholate) and enzymes (DNAse/RNAse). the presence of cellular material, collagen structural integrity and basement membrane proteins were assessed histologically. To address cytocompatibility, porcine adipose derived-mesenchymal stem cells (AD-MSC) were harvested from abdominal fat together with vaginal epithelial cells (VEC) and seeded onto the mucosal aspect of the vaginal scaffold. Both cells populations were seeded individually and assessed histologically at days 3 and 10. MAIN OUTCOMES/RESULTS: the combination of enzymes and detergents resulted in a totally acellular matrix with very low DNA amount (control= 97.5ng/μl ± 10.8 vs DC= 40.1 ng/μl ±0.33 p=0.02). The extra cellular matrix (ECM) showed retention of collagen fibres and elastin and a 50% retention in glycosaminoglycan content; (control= 1.18μg/mg ± 0.28 DC = 1.35μg/mg ± 0.1 p=0.03) and an intact basement membrane (positive for both laminin and collagen IV). Seeded scaffolds showed cell attachment with both AD-MSC and VEC at days 3 and 10. it is possible to generate an acellular porcine vaginal matrix capable of supporting cells to reconstruct the vagina for future pre-clinical testing, and holds promise for creating clinically relevant sized tissue for human application. Copyright © 2018. Published by Elsevier Inc.

On Nb Silicide Based Alloys: Alloy Design and Selection.

PubMed

Tsakiropoulos, Panos

2018-05-18

The development of Nb-silicide based alloys is frustrated by the lack of composition-process-microstructure-property data for the new alloys, and by the shortage of and/or disagreement between thermodynamic data for key binary and ternary systems that are essential for designing (selecting) alloys to meet property goals. Recent publications have discussed the importance of the parameters δ (related to atomic size), Δχ (related to electronegativity) and valence electron concentration (VEC) (number of valence electrons per atom filled into the valence band) for the alloying behavior of Nb-silicide based alloys (J Alloys Compd 748 (2018) 569), their solid solutions (J Alloys Compd 708 (2017) 961), the tetragonal Nb₅Si₃ (Materials 11 (2018) 69), and hexagonal C14-NbCr₂ and cubic A15-Nb₃X phases (Materials 11 (2018) 395) and eutectics with Nb ss and Nb₅Si₃ (Materials 11 (2018) 592). The parameter values were calculated using actual compositions for alloys, their phases and eutectics. This paper is about the relationships that exist between the alloy parameters δ, Δχ and VEC, and creep rate and isothermal oxidation (weight gain) and the concentrations of solute elements in the alloys. Different approaches to alloy design (selection) that use property goals and these relationships for Nb-silicide based alloys are discussed and examples of selected alloy compositions and their predicted properties are given. The alloy design methodology, which has been called NICE (Niobium Intermetallic Composite Elaboration), enables one to design (select) new alloys and to predict their creep and oxidation properties and the macrosegregation of Si in cast alloys.

On Nb Silicide Based Alloys: Alloy Design and Selection

PubMed Central

Tsakiropoulos, Panos.

2018-01-01

The development of Nb-silicide based alloys is frustrated by the lack of composition-process-microstructure-property data for the new alloys, and by the shortage of and/or disagreement between thermodynamic data for key binary and ternary systems that are essential for designing (selecting) alloys to meet property goals. Recent publications have discussed the importance of the parameters δ (related to atomic size), Δχ (related to electronegativity) and valence electron concentration (VEC) (number of valence electrons per atom filled into the valence band) for the alloying behavior of Nb-silicide based alloys (J Alloys Compd 748 (2018) 569), their solid solutions (J Alloys Compd 708 (2017) 961), the tetragonal Nb5Si3 (Materials 11 (2018) 69), and hexagonal C14-NbCr2 and cubic A15-Nb3X phases (Materials 11 (2018) 395) and eutectics with Nbss and Nb5Si3 (Materials 11 (2018) 592). The parameter values were calculated using actual compositions for alloys, their phases and eutectics. This paper is about the relationships that exist between the alloy parameters δ, Δχ and VEC, and creep rate and isothermal oxidation (weight gain) and the concentrations of solute elements in the alloys. Different approaches to alloy design (selection) that use property goals and these relationships for Nb-silicide based alloys are discussed and examples of selected alloy compositions and their predicted properties are given. The alloy design methodology, which has been called NICE (Niobium Intermetallic Composite Elaboration), enables one to design (select) new alloys and to predict their creep and oxidation properties and the macrosegregation of Si in cast alloys. PMID:29783707

Análise da aplicação e dos resultados do modelo OPM3® para a área da saúde

PubMed Central

Augusto dos Santos, Luis; de Fátima Marin, Heimar

2015-01-01

Esta pesquisa procurou analisar se um modelo de questionário criado por uma comunidade internacional de gerenciamento de projetos e se é aplicavél a organizações voltadas a área de saúde. O modelo OPM3® (Organizational Project Management Maturity Model) foi criado para que organizações de qualquer área ou porte pudessem identificar a presença, ou ausência, de boas práticas de gerenciamento. O objetivo da aplicação desse modelo é avaliar sempre a organização e não o entrevistado. No presente artigo, são apresentados os resultados da aplicação desse modelo em uma organização que possuía produtos e serviços de tecnologia da informação aplicados à área de saúde. Este estudo verificou que o modelo é aplicável de forma rápida e que a organização analisada possuía um número expressivo de boas práticas. PMID:26924862

Developing Breast Cancer Program at Xavier; Genomic and Proteomic Analysis of Signaling Pathways Involved in Xenohormone and MEK5 Regulation of Breast Cancer

DTIC Science & Technology

2009-05-01

that upregulations of Vimentin (VIM), Heat shock 70 kDa protein 4 (HSPA4), Glutathione S-transferase P ( GSTP1 ), and Creatine kinase B-type (CKB), and...MEK5 versus MCF-7-VEC cells, vimentin (VIM), glutathione-S-transferase P ( GSTP1 ), and creatine kinase B-type (CKB) were upregulated, and keratin 8...with distinct proteomic changes (upregulation of VIM/vim, GSTP1 / gstp1 , and CKB/ckb; and downregulation of KRT8/krt8, KRT19/krt19, and GSTM3/gstm3). We

Characterization and complete genome sequences of L. rhamnosus DSM 14870 and L. gasseri DSM 14869 contained in the EcoVag® probiotic vaginal capsules.

PubMed

Marcotte, Harold; Krogh Andersen, Kasper; Lin, Yin; Zuo, Fanglei; Zeng, Zhu; Larsson, Per Göran; Brandsborg, Erik; Brønstad, Gunnar; Hammarström, Lennart

2017-12-01

Lactobacillus rhamnosus DSM 14870 and Lactobacillus gasseri DSM 14869 were previously isolated from the vaginal epithelial cells (VEC) of healthy women and selected for the development of the vaginal EcoVag ® probiotic capsules. EcoVag ® was subsequently shown to provide long-term cure and reduce relapse of bacterial vaginosis (BV) as an adjunct to antibiotic therapy. To identify genes potentially involved in probiotic activity, we performed genome sequencing and characterization of the two strains. The complete genome analysis of both strains revealed the presence of genes encoding functions related to adhesion, exopolysaccharide (EPS) biosynthesis, antimicrobial activity, and CRISPR adaptive immunity but absence of antibiotic resistance genes. Interesting features of L. rhamnosus DSM 14870 genome include the presence of the spaCBA-srtC gene encoding spaCBA pili and interruption of the gene cluster encoding long galactose-rich EPS by integrases. Unique to L. gasseri DSM 14869 genome was the presence of a gene encoding a putative (1456 amino acid) new adhesin containing two rib/alpha-like repeats. L. rhamnosus DSM 14870 and L. gasseri DSM 14869 showed acidification of the culture medium (to pH 3.8) and a strong adhesion capability to the Caco-2 cell line and VEC. L. gasseri DSM 14869 could produce a thick (40nm) EPS layer and hydrogen peroxide. L. rhamnosus DSM 14870 was shown to produce SpaCBA pili and a 20nm EPS layer, and could inhibit the growth of Gardnerella vaginalis, a bacterium commonly associated with BV. The genome sequences provide a basis for further elucidation of the molecular basis for their probiotic functions. Copyright © 2017 Elsevier GmbH. All rights reserved.

Manipulation of a VEGF-Notch signaling circuit drives formation of functional vascular endothelial progenitors from human pluripotent stem cells

PubMed Central

Sahara, Makoto; Hansson, Emil M; Wernet, Oliver; Lui, Kathy O; Später, Daniela; Chien, Kenneth R

2014-01-01

Human pluripotent stem cell (hPSC)-derived endothelial lineage cells constitutes a promising source for therapeutic revascularization, but progress in this arena has been hampered by a lack of clinically-scalable differentiation protocols and inefficient formation of a functional vessel network integrating with the host circulation upon transplantation. Using a human embryonic stem cell reporter cell line, where green fluorescent protein expression is driven by an endothelial cell-specific VE-cadherin (VEC) promoter, we screened for > 60 bioactive small molecules that would promote endothelial differentiation, and found that administration of BMP4 and a GSK-3β inhibitor in an early phase and treatment with VEGF-A and inhibition of the Notch signaling pathway in a later phase led to efficient differentiation of hPSCs to the endothelial lineage within six days. This sequential approach generated > 50% conversion of hPSCs to endothelial cells (ECs), specifically VEC+CD31+CD34+CD14−KDRhigh endothelial progenitors (EPs) that exhibited higher angiogenic and clonogenic proliferation potential among endothelial lineage cells. Pharmaceutical inhibition or genetical knockdown of Notch signaling, in combination with VEGF-A treatment, resulted in efficient formation of EPs via KDR+ mesodermal precursors and blockade of the conversion of EPs to mature ECs. The generated EPs successfully formed functional capillary vessels in vivo with anastomosis to the host vessels when transplanted into immunocompromised mice. Manipulation of this VEGF-A-Notch signaling circuit in our protocol leads to rapid large-scale production of the hPSC-derived EPs by 12- to 20-fold vs current methods, which may serve as an attractive cell population for regenerative vascularization with superior vessel forming capability compared to mature ECs. PMID:24810299

Looking up, down, and sideways: Reconceiving cumulative effects assessment as a mindset

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sinclair, A. John, E-mail: jsincla@umanitoba.ca; Doelle, Meinhard, E-mail: mdoelle@dal.ca; Duinker, Peter N., E-mail: peter.duinker@dal.ca

Despite all the effort that has gone into defining, researching and establishing best practices for cumulative effects assessment (CEA), understanding remains weak and practice wanting. At one extreme of implementation, CEA can be described as merely an irritant to the completion of a project-specific environmental assessment (EA). At the other extreme, the conceptual view is that all effects in EA should be deemed cumulative unless demonstrated otherwise. Our purpose here is to consider how we might reconceive CEA as a mindset that is at the heart of absolutely every assessment of valued ecosystem component (VEC) to ensure that we understandmore » the relative contributions of various stressors and can decide when cumulative effects may foreclose future activities due to impacts on VECs. Conceptually, we ground the CEA mindset in the context of three lenses that must all be functioning and working together for the mindset to be operative: a technical lens; a law and policy lens; and a participatory lens. Our arguments are based on a review of the CEA, strategic effects assessment (SEA) and regional effects assessment literatures, an examination and consideration of Canadian EA and SEA case practice, and our combined professional experiences. Through using the Bay of Fundy in Canada as a case example, we establish the concept of the CEA mindset and an approach for moving forward with implementation. - Highlights: • Conceptualization of cumulative effects assessment as a mindset. • Elaboration of technical, law and policy and participation lenses critical to CEA • Coordination and integration of cumulative effects for valued ecosystem components • Application in Bay of Fundy ecosystem and terrestrial watershed.« less

Inhibition of cell migration by focal adhesion kinase: Time-dependent difference in integrin-induced signaling between endothelial and hepatoblastoma cells.

PubMed

Yu, Hongchi; Gao, Min; Ma, Yunlong; Wang, Lijuan; Shen, Yang; Liu, Xiaoheng

2018-05-01

angiogenesis plays an important role in the development and progression of tumors, and it involves a series of signaling pathways contributing to the migration of endothelial cells for vascularization and to the invasion of cancer cells for secondary tumor formation. Among these pathways, the focal adhesion kinase (FAK) signaling cascade has been implicated in a variety of human cancers in connection with cell adhesion and migration events leading to tumor angiogenesis, metastasis and invasion. Therefore, the inhibition of FAK in endothelial and/or cancer cells is a potential target for anti‑angiogenic therapy. In the present study, a small‑molecule FAK inhibitor, 1,2,4,5-benzenetetramine tetrahydrochloride (Y15), was used to study the effects of FAK inhibition on the adhesion and migration behaviors of vascular endothelial cells (VECs) and human hepatoblastoma cells. Furthermore, the time-dependent differences in proteins associated with the integrin-mediated FAK/Rho GTPases signaling pathway within 2 h were examined. The results indicated that the inhibition of FAK significantly decreased the migration ability of VECs and human hepatoblastoma cells in a dose-dependent manner. Inhibition of FAK promoted cell detachment by decreasing the expression of focal adhesion components, and blocked cell motility by reducing the level of Rho GTPases. However, the expression of crucial proteins involved in integrin-induced signaling in two cell lines exhibited a time-dependent difference with increased duration of FAK inhibitor treatment, suggesting different mechanisms of FAK-mediated cell migration behavior. These results suggest that the mechanism underlying FAK-mediated adhesion and migration behavior differs among various cells, which is expected to provide evidence for future FAK therapy targeted against tumor angiogenesis.

Construyendo modelos confiables de estrellas rías

NASA Astrophysics Data System (ADS)

Mauas, P. J.; Falchi, A.

Se estudian las aproximaciones que se realizan usualmente al calcular modelos de estrellas frías (redistribución completa para la lí nea Lyman-α, despreciar el ``line-blanketing", suponer los metales en LTE), y cómo influyen en los distintos observables. Asimismo, se evalúa cuál es la información que cada observable nos da sobre la atmósfera de la estrella, y cuáles son las incertidumbres de cada modelo.

5W1H Information Extraction with CNN-Bidirectional LSTM

NASA Astrophysics Data System (ADS)

Nurdin, A.; Maulidevi, N. U.

2018-03-01

In this work, information about who, did what, when, where, why, and how on Indonesian news articles were extracted by combining Convolutional Neural Network and Bidirectional Long Short-Term Memory. Convolutional Neural Network can learn semantically meaningful representations of sentences. Bidirectional LSTM can analyze the relations among words in the sequence. We also use word embedding word2vec for word representation. By combining these algorithms, we obtained F-measure 0.808. Our experiments show that CNN-BLSTM outperforms other shallow methods, namely IBk, C4.5, and Naïve Bayes with the F-measure 0.655, 0.645, and 0.595, respectively.

Electron-Poor Polar Intermetallics: Complex Structures, Novel Clusters, and Intriguing Bonding with Pronounced Electron Delocalization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Qisheng; Miller, Gordon J.

Intermetallic compounds represent an extensive pool of candidates for energy related applications stemming from magnetic, electric, optic, caloric, and catalytic properties. The discovery of novel intermetallic compounds can enhance understanding of the chemical principles that govern structural stability and chemical bonding as well as finding new applications. Valence electron-poor polar intermetallics with valence electron concentrations (VECs) between 2.0 and 3.0 e –/atom show a plethora of unprecedented and fascinating structural motifs and bonding features. Furthermore, establishing simple structure-bonding-property relationships is especially challenging for this compound class because commonly accepted valence electron counting rules are inappropriate.

Electron-Poor Polar Intermetallics: Complex Structures, Novel Clusters, and Intriguing Bonding with Pronounced Electron Delocalization

DOE PAGES

Lin, Qisheng; Miller, Gordon J.

2017-12-18

Intermetallic compounds represent an extensive pool of candidates for energy related applications stemming from magnetic, electric, optic, caloric, and catalytic properties. The discovery of novel intermetallic compounds can enhance understanding of the chemical principles that govern structural stability and chemical bonding as well as finding new applications. Valence electron-poor polar intermetallics with valence electron concentrations (VECs) between 2.0 and 3.0 e –/atom show a plethora of unprecedented and fascinating structural motifs and bonding features. Furthermore, establishing simple structure-bonding-property relationships is especially challenging for this compound class because commonly accepted valence electron counting rules are inappropriate.

Experimental and numerical investigations of higher mode effects on seismic inelastic response of reinforced concrete shear walls

NASA Astrophysics Data System (ADS)

Ghorbanirenani, Iman

This thesis presents two experimental programs together with companion numerical studies that were carried out on reinforced concrete shear walls: static tests and dynamic (shake table) tests. The first series of experiments were monotonic and cyclic quasi-static testing on ductile reinforced concrete shear wall specimens designed and detailed according to the seismic provisions of NBCC 2005 and CSA-A23.3-04 standard. The tests were carried out on full-scale and 1:2.37 reduced scale wall specimens to evaluate the seismic design provisions and similitude law and determine the appropriate scaling factor that could be applied for further studies such as dynamic tests. The second series of experiments were shake table tests conducted on two identical 1:2.33 scaled, 8-storey moderately ductile reinforced concrete shear wall specimens to investigate the effects of higher modes on the inelastic response of slender walls under high frequency ground motions expected in Eastern North America. The walls were designed and detailed according to the seismic provisions of NBCC 2005 and CSA-A23.3-04 standard. The objectives were to validate and understand the inelastic response and interaction of shear, flexure and axial loads in plastic hinge zones of the walls considering the higher mode effects and to investigate the formation of second hinge in upper part of the wall due to higher mode responses. Second mode response significantly affected the response of the walls. This caused inelastic flexural response to develop at the 6th level with approximately the same rotation ductility compared to that observed at the base. Dynamic amplification of the base shear forces was also observed in both walls. Numerical modeling of these two shake table tests was performed to evaluate the test results and validate current modeling approaches. Nonlinear time history analyses were carried out by the reinforced concrete fibre element (OpenSees program) and finite element (VecTor2 program) methods using the shake table feedback signals as input. Good agreement was generally obtained between numerical and experimental results. Both computer programs were able to predict the natural frequency of the walls in the undamaged and damaged conditions. Both modeling techniques could predict that the maximum bending moment at the base of the walls reached the actual wall moment capacity. The inelastic response and the dual plastic hinge behaviour of the walls could be adequately reproduced using the fibre element and finite element analysis programs. The fibre element method is a good alternative in terms of computing time. It produces reasonable results in comparison with the finite element method, although particular attention needs to be given to the selection of the damping ratios. The different parametric analyses performed in this thesis showed that, for both models, adding a small amount of global viscous damping in combination with a refined reinforced concrete hysteretic model could predict better the seismic behaviour of the tested structures. For the VecTor2 program, a viscous damping of 1% led to reasonable results for the studied RC walls. For the OpenSees program, 2% damping resulted in a good match between test and predictions for the 100% EQ test on the initially undamaged wall. When increasing the earthquake intensities, the damping had to be reduced between 1.5% and 1% to achieve good results for a damaged wall with elongated vibration periods. According to the experimental results and numerical analyses on reinforced concrete shear walls subjected to ground motions from Eastern North America earthquakes, there is a high possibility of having a second plastic hinge forming in the upper part of walls in addition to the one assumed in design at the base. This second hinge could dissipate the earthquake energy more effectively and decrease the force demand on the wall. A dual plastic hinge design approach in which the structures become plastic in the upper wall segment as well as the base could be therefore more appropriate. Preliminary design recommendations considering higher mode effects on dual hinge response and base shear forces for ductile slender shear walls are given in this thesis. (Abstract shortened by UMI.)

Estudio de distintos modelos de protuberancias solares

NASA Astrophysics Data System (ADS)

Cirigliano, D.; Rovira, M.; Mauas, P.

En este trabajo presentamos perfiles de líneas del CaII, MgII y HeI calculados para distintos modelos de protuberancias, y los comparamos con observaciones obtenidas por los satélites OSO 8 y SOHO. Para obtener las poblaciones de los distintos niveles de los átomos, utilizamos un código numérico que combina las ecuaciones de transporte de radiación y equilibrio estadístico en un único sistema de ecuaciones no lineal. Los modelos básicos que consideramos para las protuberancias consisten en placas homogéneas y unidimensionales apoyadas sobre la superficie del Sol. Dichas placas se hallan estratificadas en hebras y los modelos difieren entre sí en la temperatura y ancho de la placa, en la presión a la cual se halla el plasma y en el número de hebras. A partir de estos modelos se investiga cada uno de estos parámetros libres y como influyen en la atmósfera de las protuberancias solares y en el perfil de línea de cada especie estudiada, con el objetivo de determinar las condiciones en las que se halla el material atmosférico de estas protuberancias.

Modelo analítico del efecto de PRS sobre satélites GPS

NASA Astrophysics Data System (ADS)

Meza, A.; Brunini, C.; Usandivaras, J. C.

El sistema GPS (Global Position System) es, hoy en día, la herramienta de navegación y posicionamiento más potente y lo será sin duda en la próxima década. Gran parte de su valiosa utilidad se debe a la alta precisión que permite lograr y ésta, a su vez, depende, entre otras causas, de la precisión con que se conocen las órbitas de los satélites. La presión de radiación solar (PRS) fija el límite de la precisión con que pueden calcularse en la actualidad las efemérides satelitarias. El objetivo de este trabajo es proponer una mejor resolución de este fenómeno. El modelo analítico aquí presentado, se basa en el análisis del comportamiento de los residuos de un ajuste por mínimos cuadrados en el que se utiliza el modelo de PRS propuesto por Beutler. El mismo consiste en un modelo determinista del fenómeno con dos parámetros libres. Los resultados obtenidos ponen de manifiesto que, aún después de aplicar dichos parámetros, prevalecen en los residuos efectos semidiurnos en las componentes radial,tangencial y normal. Estos resultados obtenidos se comparan con los de un trabajo desarrollado por el Instituto de Berne (Beutler et al., 1994), en el que se utilizaron como pseudo-observaciones las órbitas precisas del IGS (CODE). El intervalo de integración escogido por este centro fueron las semanas 680 y 681. En resumen se tienen arcos de 14 días para todos los satélites, donde las efemérides precisas de los mismos para los 14 días fueron utilizados como pseudo-observaciones. El modelo de fuerza que empleó dicho centro fue básicamente el tradicional en lo que respecta al modelo de las fuerzas gravitacionales, y para la PRS utilizo el modelo standard de Beutler. Los parámetros de este modelo junto con las 6 condiciones iniciales (posición y velocidad) fueron ajustados por el método general de mínimos cuadrados. Los residuos en la componente radial, tangencial y normal, para los satélites con un buen comportamiento, presentan una componente semidiurna. El modelo analítico planteado en este trabajo, predice el comportamiento de los residuos que se observan en las publicaciones más recientes. Esto abre el camino para plantear una estimación distinta de las incógnitas del problema, basado en el método de colocación por mínimos cuadrados. Ello requiere modelar estadísticamente la señal debida a las componentes de la PRS que no son tomadas en cuenta en el modelo determinista.

Espectro de radiación derivado de un modelo de colapso protoestelar

NASA Astrophysics Data System (ADS)

Coca, S.; Rohrmann, R.

El exceso de emisión infrarroja en objetos protoestelares es atribuido usualmente a un disco de material en torno al cuerpo central. A pesar del avance alcanzado en la elaboración de modelos, aún existen dificultades para explicar la ley de temperatura del disco necesaria para reproducir las luminosidades y perfiles de energía observados. Nuestra propuesta consiste en determinar la distribución espectral de la radiación derivada de un particular modelo de colapso protoestelar, y estudiar la evolución del espectro desde estadíos tempranos de la contracción gravitatoria. Este plan es orientado a evaluar las propiedades del modelo (distribuciones de masa y temperatura del material circunestelar) por comparación con datos observacionales, a fin de inferir de ello los posibles ajustes requeridos en la teoría actualmente empleada.

Discos de acreción circumplanares: Modelo de Co-acreción

NASA Astrophysics Data System (ADS)

Parisi, M. G.; de Elía, G.

Los discos de acreción circumplanetarios precursores de los satélites regulares de los planetas gigantes, se pueden formar por cuatro mecanismos (Pollack y otros, 1991, In Uranus, Bergtralh, Miner y Mattews, Eds., p. 469, Univ. de Arizona Press, Tucson). En este trabajo estudiamos uno de tales mecanismos: el Modelo de Co-acreción. En dicho modelo, el disco circumplanetario se forma a partir de las colisiones mutuas entre planetesimales dentro de la esfera de Hill del planeta durante el proceso de formación planetaria. Realizamos un modelo semi-analítico para calcular la masa del disco y compararla con la masa requerida para formar los satélites regulares de los planetas gigantes. Hemos obtenido una cota superior para la masa del disco que resulta inferior a la masa de los satélites más grandes de los planetas gigantes. En principio, estos resultados permitirían descartar el modelo de co-acreción como uno de los procesos que podrían dar lugar a la formación de los satélites regulares. Estos resultados permiten obtener restricciones en el escenario de formación planetaria y en los mecanismos de formación de sistemas de satélites.

The conceptualization model problem—surprise

NASA Astrophysics Data System (ADS)

Bredehoeft, John

2005-03-01

The foundation of model analysis is the conceptual model. Surprise is defined as new data that renders the prevailing conceptual model invalid; as defined here it represents a paradigm shift. Limited empirical data indicate that surprises occur in 20-30% of model analyses. These data suggest that groundwater analysts have difficulty selecting the appropriate conceptual model. There is no ready remedy to the conceptual model problem other than (1) to collect as much data as is feasible, using all applicable methods—a complementary data collection methodology can lead to new information that changes the prevailing conceptual model, and (2) for the analyst to remain open to the fact that the conceptual model can change dramatically as more information is collected. In the final analysis, the hydrogeologist makes a subjective decision on the appropriate conceptual model. The conceptualization problem does not render models unusable. The problem introduces an uncertainty that often is not widely recognized. Conceptual model uncertainty is exacerbated in making long-term predictions of system performance. C'est le modèle conceptuel qui se trouve à base d'une analyse sur un modèle. On considère comme une surprise lorsque le modèle est invalidé par des données nouvelles; dans les termes définis ici la surprise est équivalente à un change de paradigme. Des données empiriques limitées indiquent que les surprises apparaissent dans 20 à 30% des analyses effectuées sur les modèles. Ces données suggèrent que l'analyse des eaux souterraines présente des difficultés lorsqu'il s'agit de choisir le modèle conceptuel approprié. Il n'existe pas un autre remède au problème du modèle conceptuel que: (1) rassembler autant des données que possible en utilisant toutes les méthodes applicables—la méthode des données complémentaires peut conduire aux nouvelles informations qui vont changer le modèle conceptuel, et (2) l'analyste doit rester ouvert au fait que le modèle conceptuel peut bien changer lorsque des nouvelles informations apparaissent. Dans l'analyse finale le hydrogéologue prend une décision subjective sur le modèle conceptuel approprié. Le problème du le modèle conceptuel ne doit pas rendre le modèle inutilisable. Ce problème introduit une incertitude qui n'est pas toujours reconnue. Les incertitudes du modèle conceptuel deviennent plus importantes dans les cases de prévisions à long terme dans l'analyse de performance. La base para hacer un análisis de un modelo es el modelo conceptual. Se define aquí la sorpresa como los datos nuevos que convierten en incoherente al modelo conceptual previamente aceptado; tal como se define aquí esto representa un cambio de paradigma. Los datos empíricos limitados indican que estas sorpresas suceden entre un 20 a un 30% de los análisis de modelos. Esto sugiere que los analistas de modelos de agua subterránea tienen dificultades al seleccionar el modelo conceptual apropiado. No hayotra solución disponible a este problema del modelo conceptual diferente de: (1) Recolectar tanta información como sea posible, mediante la utilización de todos los métodos aplicables, lo cual puede resultar en que esta nueva información ayude a cambiar el modelo conceptual vigente, y (2) Que el analista de modelos se mantenga siempre abierto al hecho de que un modelo conceptual puede cambiar de manera total, en la medida en que se colecte mas información. En el análisis final el hidrogeólogo toma una decisión subjetiva en cuanto al modelo conceptual apropiado. El problema de la conceptualización no produce modelos inútiles. El problema presenta una incertidumbre, la cual a menudo no es tenida en cuentade manera adecuada. Esta incertidumbre en los modelos conceptuales se aumenta, cuando se hacen predicciones a largo plazo del comportamiento de un sistema dado.

Bio-SimVerb and Bio-SimLex: wide-coverage evaluation sets of word similarity in biomedicine.

PubMed

Chiu, Billy; Pyysalo, Sampo; Vulić, Ivan; Korhonen, Anna

2018-02-05

Word representations support a variety of Natural Language Processing (NLP) tasks. The quality of these representations is typically assessed by comparing the distances in the induced vector spaces against human similarity judgements. Whereas comprehensive evaluation resources have recently been developed for the general domain, similar resources for biomedicine currently suffer from the lack of coverage, both in terms of word types included and with respect to the semantic distinctions. Notably, verbs have been excluded, although they are essential for the interpretation of biomedical language. Further, current resources do not discern between semantic similarity and semantic relatedness, although this has been proven as an important predictor of the usefulness of word representations and their performance in downstream applications. We present two novel comprehensive resources targeting the evaluation of word representations in biomedicine. These resources, Bio-SimVerb and Bio-SimLex, address the previously mentioned problems, and can be used for evaluations of verb and noun representations respectively. In our experiments, we have computed the Pearson's correlation between performances on intrinsic and extrinsic tasks using twelve popular state-of-the-art representation models (e.g. word2vec models). The intrinsic-extrinsic correlations using our datasets are notably higher than with previous intrinsic evaluation benchmarks such as UMNSRS and MayoSRS. In addition, when evaluating representation models for their abilities to capture verb and noun semantics individually, we show a considerable variation between performances across all models. Bio-SimVerb and Bio-SimLex enable intrinsic evaluation of word representations. This evaluation can serve as a predictor of performance on various downstream tasks in the biomedical domain. The results on Bio-SimVerb and Bio-SimLex using standard word representation models highlight the importance of developing dedicated evaluation resources for NLP in biomedicine for particular word classes (e.g. verbs). These are needed to identify the most accurate methods for learning class-specific representations. Bio-SimVerb and Bio-SimLex are publicly available.

Privacy-Preserving Predictive Modeling: Harmonization of Contextual Embeddings From Different Sources.

PubMed

Huang, Yingxiang; Lee, Junghye; Wang, Shuang; Sun, Jimeng; Liu, Hongfang; Jiang, Xiaoqian

2018-05-16

Data sharing has been a big challenge in biomedical informatics because of privacy concerns. Contextual embedding models have demonstrated a very strong representative capability to describe medical concepts (and their context), and they have shown promise as an alternative way to support deep-learning applications without the need to disclose original data. However, contextual embedding models acquired from individual hospitals cannot be directly combined because their embedding spaces are different, and naive pooling renders combined embeddings useless. The aim of this study was to present a novel approach to address these issues and to promote sharing representation without sharing data. Without sacrificing privacy, we also aimed to build a global model from representations learned from local private data and synchronize information from multiple sources. We propose a methodology that harmonizes different local contextual embeddings into a global model. We used Word2Vec to generate contextual embeddings from each source and Procrustes to fuse different vector models into one common space by using a list of corresponding pairs as anchor points. We performed prediction analysis with harmonized embeddings. We used sequential medical events extracted from the Medical Information Mart for Intensive Care III database to evaluate the proposed methodology in predicting the next likely diagnosis of a new patient using either structured data or unstructured data. Under different experimental scenarios, we confirmed that the global model built from harmonized local models achieves a more accurate prediction than local models and global models built from naive pooling. Such aggregation of local models using our unique harmonization can serve as the proxy for a global model, combining information from a wide range of institutions and information sources. It allows information unique to a certain hospital to become available to other sites, increasing the fluidity of information flow in health care. ©Yingxiang Huang, Junghye Lee, Shuang Wang, Jimeng Sun, Hongfang Liu, Xiaoqian Jiang. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 16.05.2018.

Evolução química em galáxias compactas azuis (BCGs)

NASA Astrophysics Data System (ADS)

Lanfranchi, G. A.; Matteucci, F.

2003-08-01

Neste trabalho, a formação estelar e evolução quí mica em galáxias Compactas Azuis (Blue Compact Galaxies - BCGs) foram estudadas através da comparação de previsões de modelos de evolução quí mica a várias razões de abundância quí mica observadas nestas galáxias. Modelos detalhados com recentes dados de nucleossí ntese e que levam em consideração o papel desempenahdo por supernovas de ambos os tipos (II e Ia) na evolução galáctica foram desenvolvidos para as BCGs permitindo seguir a evolução de vários elementos quí micos (H, D, He, C, N, O, Mg, Si, S, Ca, e Fe). O modelo é caracterizado pelas prescrições adotadas para a formação estelar, a qual ocorre em vários surtos de atividade separados por longos perí odos quiescentes. Após ajustar os melhores modelos aos dados observacionais, as previsões destes modelos foram comparadas também a razões de abundância observadas em sistemas Damped Lyman alpha (DLAs) e a origem do N (primária ou secundária) foi discutida. Alguns dos resultados obtidos são: i) as razões de abundância observadas nas BCGs são reproduzidas por modelos com 2 a 7 surtos de formação estelar com eficiência entre n = 0.2-0.9 Gano-1; ii) os baixos valores de N/O observados nestas galáxias são um resultado natural de uma formação estelar em surtos; iii) os modelos para BCGs podem reproduzir os dados dos DLAs, iv) uma quantidade "baixa" de N primário produzido em estrelas de alta massa pode ser uma explicação para os baixos valores de [N/a] observados em DLAs.

En la búsqueda de características en eyecciones coronales de masa que discriminen entre dos paradigmas físicos en modelos de ECMs

NASA Astrophysics Data System (ADS)

Paissan, G.; Stenborg, G.; Rovira, M.

Se conocen tres diferentes fenómenos de gran escala que ocurren en la atmósfera solar, denominados eyecciones coronales de masa (ECMs), protuberancias eruptivas y grandes fulguraciones de dos bandas. Estos fenómenos están estrechamente relacionados y podrían ser distintas manifestaciones de un único proceso físico. Las ECMs son definidas como eyecciones de gran escala de masa y flujo magnético desde la baja corona al espacio interplanetario. Desde su descubrimiento en los '70, muchos modelos han sido propuestos para explicar su origen y evolución. La explicación física de las ECMs es un tema de debate intenso. No obstante, los modelos pueden sintetizarse en dos grandes grupos: 1) los modelos de inyección de flujo y 2) los modelos de almacenamiento y liberación. En este trabajo, se presentan los estudios realizados con una serie de eventos observados con el coronógrafo MICA (Mirror Coronograph for Argentina), el telescopio en H-alfa HASTA (H-alpha Solar Telescope for Argentina) y los coronógrafos C2 y C3 de la sonda SOHO (Solar and Heliospheric Observatory). Los eventos que pudieron ser identificados como ECMs son contrastados dentro del esquema de los dos paradigmas teóricos propuestos.

Oncolytic virus therapy: A new era of cancer treatment at dawn.

PubMed

Fukuhara, Hiroshi; Ino, Yasushi; Todo, Tomoki

2016-10-01

Oncolytic virus therapy is perhaps the next major breakthrough in cancer treatment following the success in immunotherapy using immune checkpoint inhibitors. Oncolytic viruses are defined as genetically engineered or naturally occurring viruses that selectively replicate in and kill cancer cells without harming the normal tissues. T-Vec (talimogene laherparepvec), a second-generation oncolytic herpes simplex virus type 1 (HSV-1) armed with GM-CSF, was recently approved as the first oncolytic virus drug in the USA and Europe. The phase III trial proved that local intralesional injections with T-Vec in advanced malignant melanoma patients can not only suppress the growth of injected tumors but also act systemically and prolong overall survival. Other oncolytic viruses that are closing in on drug approval in North America and Europe include vaccinia virus JX-594 (pexastimogene devacirepvec) for hepatocellular carcinoma, GM-CSF-expressing adenovirus CG0070 for bladder cancer, and Reolysin (pelareorep), a wild-type variant of reovirus, for head and neck cancer. In Japan, a phase II clinical trial of G47∆, a third-generation oncolytic HSV-1, is ongoing in glioblastoma patients. G47∆ was recently designated as a "Sakigake" breakthrough therapy drug in Japan. This new system by the Japanese government should provide G47∆ with priority reviews and a fast-track drug approval by the regulatory authorities. Whereas numerous oncolytic viruses have been subjected to clinical trials, the common feature that is expected to play a major role in prolonging the survival of cancer patients is an induction of specific antitumor immunity in the course of tumor-specific viral replication. It appears that it will not be long before oncolytic virus therapy becomes a standard therapeutic option for all cancer patients. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Fluctuation reduction and enhanced confinement in the MST reversed-field pinch

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chapman, Brett Edward

1997-10-01

Plasmas with a factor of ≥3 improvement in energy confinement have been achieved in the MST reversed-field pinch (RFP). These plasmas occur spontaneously, following sawtooth crashes, subject to constraints on, eg, toroidal magnetic field reversal and wall conditioning. Possible contributors to the improved confinement include a reduction of core-resonant, global magnetic fluctuations and a reduction of electrostatic fluctuations over the entire plasma edge. One feature of these plasmas is a region of strong ExB flow shear in the edge. Never before observed in conjunction with enhanced confinement in the RFP, such shear is common in enhanced confinement discharges in tokamaks and stellarators. Another feature of these plasmas is a new type of discrete dynamo event. Like sawtooth crashes, a common form of discrete dynamo, these events correspond to bursts of edge parallel current. The reduction of electrostatic fluctuations in these plasmas occurs within and beyond the region of strong ExB flow shear, similar to what is observed in tokamaks and stellarators. However, the reductions in the MST include fluctuations whose correlation lengths are larger than the width of the shear region. The reduction of the global magnetic fluctuations is most likely due to flattening of the μ=μ 0more » $$\\vec{J}$$∙$$\\vec{B}$$/B 2 profile. Flattening can occur, eg, due to the new type of discrete dynamo event and reduced edge resistivity. Enhanced confinement plasmas are also achieved in the MST when auxiliary current is applied to flatten the μ profile and reduce magnetic fluctuations. Unexpectedly, these plasmas also exhibit a region (broader than in the case above) of strong ExB flow shear in the edge, an edge-wide reduction of electrostatic fluctuations, and the new type of discrete dynamo event. Auxiliary current drive has historically been viewed as the principal route to fusion reactor viability for the RFP.« less

Large-scale expansion of γδ T cells and peptide-specific cytotoxic T cells using zoledronate for adoptive immunotherapy.

PubMed

Yoshikawa, Toshiaki; Takahara, Masashi; Tomiyama, Mai; Nieda, Mie; Maekawa, Ryuji; Nakatsura, Tetsuya

2014-11-01

Specific cellular immunotherapy for cancer requires efficient generation and expansion of cytotoxic T lymphocytes (CTLs) that recognize tumor-associated antigens. However, it is difficult to isolate and expand functionally active T-cells ex vivo. In this study, we investigated the efficacy of a new method to induce expansion of antigen-specific CTLs for adoptive immunotherapy. We used tumor-associated antigen glypican-3 (GPC3)-derived peptide and cytomegalovirus (CMV)-derived peptide as antigens. Treatment of human peripheral blood mononuclear cells (PBMCs) with zoledronate is a method that enables large-scale γδ T-cell expansion. To induce expansion of γδ T cells and antigen-specific CTLs, the PBMCs of healthy volunteers or patients vaccinated with GPC3 peptide were cultured with both peptide and zoledronate for 14 days. The expansion of γδ T cells and peptide-specific CTLs from a few PBMCs using zoledronate yields cell numbers sufficient for adoptive transfer. The rate of increase of GPC3‑specific CTLs was approximately 24- to 170,000-fold. These CD8(+) cells, including CTLs, showed GPC3-specific cytotoxicity against SK-Hep-1/hGPC3 and T2 pulsed with GPC3 peptide, but not against SK-Hep-1/vec and T2 pulsed with human immunodeficiency virus peptide. On the other hand, CD8(-) cells, including γδ T cells, showed cytotoxicity against SK-Hep-1/hGPC3 and SK-Hep-1/vec, but did not show GPC3 specificity. Furthermore, adoptive cell transfer of CD8(+) cells, CD8(-) cells, and total cells after expansion significantly inhibited tumor growth in an NOD/SCID mouse model. This study indicates that simultaneous expansion of γδ T cells and peptide-specific CTLs using zoledronate is useful for adoptive immunotherapy.

Intravenous Lipid Infusion Induces Endoplasmic Reticulum Stress in Endothelial Cells and Blood Mononuclear Cells of Healthy Adults.

PubMed

Tampakakis, Emmanouil; Tabit, Corey E; Holbrook, Monika; Linder, Erika A; Berk, Brittany D; Frame, Alissa A; Bretón-Romero, Rosa; Fetterman, Jessica L; Gokce, Noyan; Vita, Joseph A; Hamburg, Naomi M

2016-01-11

Endoplasmic reticulum (ER) stress and the subsequent unfolded protein response may initially be protective, but when prolonged, have been implicated in atherogenesis in diabetic conditions. Triglycerides and free fatty acids (FFAs) are elevated in patients with diabetes and may contribute to ER stress. We sought to evaluate the effect of acute FFA elevation on ER stress in endothelial and circulating white cells. Twenty-one healthy subjects were treated with intralipid (20%; 45 mL/h) plus heparin (12 U/kg/h) infusion for 5 hours. Along with increased triglyceride and FFA levels, intralipid/heparin infusion reduced the calf reactive hyperemic response without a change in conduit artery flow-mediated dilation consistent with microvascular dysfunction. To investigate the short-term effects of elevated triglycerides and FFA, we measured markers of ER stress in peripheral blood mononuclear cells (PBMCs) and vascular endothelial cells (VECs). In VECs, activating transcription factor 6 (ATF6) and phospho-inositol requiring kinase 1 (pIRE1) proteins were elevated after infusion (both P<0.05). In PBMCs, ATF6 and spliced X-box-binding protein 1 (XBP-1) gene expression increased by 2.0- and 2.5-fold, respectively (both P<0.05), whereas CHOP and GADD34 decreased by ≈67% and 74%, respectively (both P<0.01). ATF6 and pIRE1 protein levels also increased (both P<0.05), and confocal microscopy revealed the nuclear localization of ATF6 after infusion, suggesting activation. Along with microvascular dysfunction, intralipid infusion induced an early protective ER stress response evidenced by activation of ATF6 and IRE1 in both leukocytes and endothelial cells. Our results suggest a potential link between metabolic disturbances and ER stress that may be relevant to vascular disease. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Room-temperature ferromagnetic transitions and the temperature dependence of magnetic behaviors in FeCoNiCr-based high-entropy alloys

NASA Astrophysics Data System (ADS)

Na, Suok-Min; Yoo, Jin-Hyeong; Lambert, Paul K.; Jones, Nicholas J.

2018-05-01

High-entropy alloys (HEAs) containing multiple principle alloying elements exhibit unique properties so they are currently receiving great attention for developing innovative alloy designs. In FeCoNi-based HEAs, magnetic behaviors strongly depend on the addition of alloying elements, usually accompanied by structural changes. In this work, the effect of non-magnetic components on the ferromagnetic transition and magnetic behaviors in equiatomic FeCoNiCrX (X=Al, Ga, Mn and Sn) HEAs was investigated. Alloy ingots of nominal compositions of HEAs were prepared by arc melting and the button ingots were cut into discs for magnetic measurements as functions of magnetic field and temperature. The HEAs of FeCoNiCrMn and FeCoNiCrSn show typical paramagnetic behaviors, composed of solid solution FCC matrix, while the additions of Ga and Al in FeCoNiCr exhibit ferromagnetic behaviors, along with the coexistence of FCC and BCC phases due to spinodal decomposition. The partial phase transition in both HEAs with the additions of Ga and Al would enhance ferromagnetic properties due to the addition of the BCC phase. The saturation magnetization for the base alloy FeCoNiCr is 0.5 emu/g at the applied field of 20 kOe (TC = 104 K). For the HEAs of FeCoNiCrGa and FeCoNiCrAl, the saturation magnetization significantly increased to 38 emu/g (TC = 703 K) and 25 emu/g (TC = 277 K), respectively. To evaluate the possibility of solid solution FCC and BCC phases in FeCoNiCr-type HEAs, we introduced a parameter of valence electron concentration (VEC). The proposed rule for solid solution formation by the VEC was matched with FeCoNiCr-type HEAs.

Endothelial precursor cells promote angiogenesis in hepatocellular carcinoma.

PubMed

Sun, Xi-Tai; Yuan, Xian-Wen; Zhu, Hai-Tao; Deng, Zheng-Ming; Yu, De-Cai; Zhou, Xiang; Ding, Yi-Tao

2012-09-21

To investigate the role of bone marrow-derived endothelial progenitor cells (EPCs) in the angiogenesis of hepatocellular carcinoma (HCC). The bone marrow of HCC mice was reconstructed by transplanting green fluorescent protein (GFP) + bone marrow cells. The concentration of circulating EPCs was determined by colony-forming assays and fluorescence-activated cell sorting. Serum and tissue levels of vascular endothelial growth factor (VEGF) and colony-stimulating factor (CSF) were quantified by enzyme-linked immunosorbent assay. The distribution of EPCs in tumor and tumor-free tissues was detected by immunohistochemistry and real-time polymerase chain reaction. The incorporation of EPCs into hepatic vessels was examined by immunofluorescence and immunohistochemistry. The proportion of EPCs in vessels was then calculated. The HCC model was successful established. The flow cytometry analysis showed the mean percentage of CD133CD34 and CD133VEGFR2 double positive cells in HCC mice was 0.45% ± 0.16% and 0.20% ± 0.09% respectively. These values are much higher than in the sham-operation group (0.11% ± 0.13%, 0.05% ± 0.11%, n = 9) at 14 d after modeling. At 21 d, the mean percentage of circulating CD133CD34 and CD133VEGFR2 cells is 0.23% ± 0.19%, 0.25% ± 0.15% in HCC model vs 0.05% ± 0.04%, 0.12% ± 0.11% in control. Compared to the transient increase observed in controls, the higher level of circulating EPCs were induced by HCC. In addition, the level of serum VEGF and CSF increased gradually in HCC, reaching its peak 14 d after modeling, then slowly decreased. Consecutive sections stained for the CD133 and CD34 antigens showed that the CD133+ and CD34+ VEGFR2 cells were mostly recruited to HCC tissue and concentrated in tumor microvessels. Under fluorescence microscopy, the bone-marrow (BM)-derived cells labeled with GFP were concentrated in the same area. The relative levels of CD133 and CD34 gene expression were elevated in tumors, around 5.0 and 3.8 times that of the tumor free area. In frozen liver sections from HCC mice, cells co-expressing CD133 and VEGFR2 were identified by immunohistochemical staining using anti-CD133 and VEGFR2 antibodies. In tumor tissue, the double-positive cells were incorporated into vessel walls. In immunofluorescent staining. These CD31 and GFP double positive cells are direct evidence that tumor vascular endothelial cells (VECs) come partly from BM-derived EPCs. The proportion of GFP CD31 double positive VECs (out of all VECs) on day 21 was around 35.3% ± 21.2%. This is much higher than the value recorded on day 7 group (17.1% ± 8.9%). The expression of intercellular adhesion molecule 1, vascular adhesion molecule 1, and VEGF was higher in tumor areas than in tumor-free tissues. Mobilized EPCs were found to participate in tumor vasculogenesis of HCC. Inhibiting EPC mobilization or recruitment to tumor tissue may be an efficient strategy for treating HCC.

Measurements of Correlated Pair Momentum Distributions in 3He(e,e'pp)n with CLAS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Niyazov, Rustam

2003-05-01

We have measured the 3He(e,e'pp)n reaction at 2.2 and 4.4 GeV over a wide kinematic range. The kinetic energy distribution for ''fast'' nucleons (p > 250 MeV/c) peaks where two nucleons each have 20% or less and the third or ''leading'' nucleon carries most of the transferred energy. These fast nucleon pairs (both pp and pn) are back-to-back and carry very little momentum alongmore » $$\\vec{q}$$, indicating that they are spectators. Experimental and theoretical evidence indicates that we have measured NN correlations in 3He(e,e'pp)n by striking the third nucleon and detecting the spectator correlated pair.« less

Aligning Greek-English parallel texts

NASA Astrophysics Data System (ADS)

Galiotou, Eleni; Koronakis, George; Lazari, Vassiliki

2015-02-01

In this paper, we discuss issues concerning the alignment of parallel texts written in languages with different alphabets based on an experiment of aligning texts from the proceedings of the European Parliament in Greek and English. First, we describe our implementation of the k-vec algorithm and its application to the bilingual corpus. Then the output of the algorithm is used as a starting point for an alignment procedure at a sentence level which also takes into account mark-ups of meta-information. The results of the implementation are compared to those of the application of the Church and Gale alignment algorithm on the Europarl corpus. The conclusions of this comparison can give useful insights as for the efficiency of alignment algorithms when applied to the particular bilingual corpus.

El rol de Ia colaboracion y el Modelo de Aprendizaje Basado en Proyectos (ABPr) mediante el lente de la Teoria de Actividad (CHAT): un estudio de caso con estudiantes de 9no grado

NASA Astrophysics Data System (ADS)

Delgado, Isabel C.

Los modelos de eensenanza y aprendizaje constructivistas conceptualizan el aprendizaje como un proceso activo. El modelo de Aprendizaje Basado en Proyectos (ABPr) se distingue por una serie de componentes, entre los cuales se destaca el aspecto colaborativo y cooperativo como un reto al momento de su implantacion. Son pocas las investigaciones que se concentran en este aspecto del modelo. En este estudio, se analizaron las diversas interacciones que surgen durante la implantacion de una unidad curricular sobre el tema de Geologia de Puerto Rico, la cual se diseno con el modelo ABPr cuyo enfoque es orientacion a proyectos. Particularmente, se examinaron las interacciones sociales que surgen entre los pares y entre pares y docente durante el proceso de planificacion y desarrollo de los productos finales, al igual que las interacciones entre los estudiantes y el material didactico en estas etapas del modelo. La investigacion es de tipo cualitativo e incorpora como diseno el estudio de caso. Las diversas interacciones constituyen la unidad de analisis. En el estudio participaron 19 estudiantes de 9no grado, a quienes se organizaron en 5 grupos colaborativos por temas de interes (Pangea, Placas tectonicas, Volcanes, Tsunamis y Terremotos). Las tecnicas que se utilizaron para recopilar los datos fueron: observaciones participativas, grupos focales y analisis de documentos (cuadernos reflexivos y respuestas de los estudiantes a la pregunta central del proyecto). Para el analisis de los datos se aplico la teoria de actividad (CHAT) que concentra la unidad de analisis en la actividad humana en un contexto particular. Los resultados del estudio senalan que las interacciones entre pares, entre pares y docente, asi como entre estudiantes y material didactico son fundamentales en el proceso de aprendizaje. Una mayor interaccion entre pares durante las etapas de planificar y desarrollar los productos finales de la unidad, promueve una mejor comprension de los conceptos de la unidad, segun evidencia los productos finales del ABPr. La interaccion con el docente es muy importante para mediar los conflictos y desacuerdos que surgen como parte de las interacciones entre pares. Por lo tanto, el uso de diversas estrategias de andamiaje por parte del docente durante las reuniones de los grupos colaborativos es esencial para el exito del modelo ABPr.

Modelo B/Dual Language Programmes in the Basque Country and the USA

ERIC Educational Resources Information Center

Torres-Guzman, Maria E.; Etxeberria, Feli

2005-01-01

In this paper, we undertake a cross-national comparison of early partial immersion programmes, known as dual language or Modelo B programmes, in the USA and the Basque Country in Spain, respectively. We attempt to make sense of their growth, the expanded social uses of the minority languages, and address seemingly contradictory pedagogical…

Primary care for diabetes mellitus patients from the perspective of the care model for chronic conditions.

PubMed

Salci, Maria Aparecida; Meirelles, Betina Hörner Schlindwein; Silva, Denise Maria Guerreiro Vieira da

2017-03-09

to assess the health care Primary Health Care professionals provide to diabetes mellitus patients from the perspective of the Modelo de Atenção às Condições Crônicas. qualitative study, using the theoretical framework of Complex Thinking and the Modelo de Atenção às Condições Crônicas and the methodological framework of assessment research. To collect the data, 38 interviews were held with health professionals and managers; observation of the activities by the health teams; and analysis of 25 files of people who received this care. The data analysis was supported by the software ATLAS.ti, using the directed content analysis technique. at the micro level, care was distant from the integrality of the actions needed to assist people with chronic conditions and was centered on the biomedical model. At the meso level, there was disarticulation among the professionals of the Family Health Strategy, between them and the users, family and community. At the macro level, there was a lack of guiding strategies to implement public policies for diabetes in care practice. the implementation of the Modelo de Atenção às Condições Crônicas represents a great challenge, mainly needing professionals and managers who are prepared to work with chronic conditions are who are open to break with the traditional model. evaluar la atención de salud desarrollada por los integrantes de la Atención Primaria de Salud a las personas con diabetes mellitus en la perspectiva del Modelo de Atenção às Condições Crônicas. estudio cualitativo, con referencial teórico del Pensamiento Complejo y del Modelo de Atenção às Condições Crônicas y metodológico de la investigación evaluativa. Para recolectar los datos fueron efectuadas 38 entrevistas con profesionales de salud y gestores; observación de las actividades practicadas por los equipos de salud: y análisis de 25 archivos de personas que recibían esa atención. Los datos fueron analizados con auxilio del software ATLAS.ti, utilizando la técnica de análisis de contenido dirigida. en el ámbito micro, la atención estaba distante de la integralidad de las acciones necesarias para asistir a las personas con enfermedad crónica y estaba centrada en el modelo biomédico. En el ámbito meso, existía desarticulación entre los profesionales de la Estrategia Salud de la Familia, entre estos y los usuarios, familia y comunidad. En el ámbito macro, se identificó ausencia de estrategias directivas para la implementación de las políticas públicas para la diabetes en la práctica asistencial. la implementación del Modelo de Atención a las Condiciones Crónicas representa un gran reto, necesitando principalmente de profesionales y gestores preparados para trabajar con enfermedades crónicas y abiertos a romper con el modelo tradicional. avaliar a atenção à saúde desenvolvida pelos integrantes da Atenção Primária à Saúde às pessoas com diabetes mellitus na perspectiva do Modelo de Atenção às Condições Crônicas. estudo qualitativo, com referencial teórico do Pensamento Complexo e do Modelo de Atenção às Condições Crônicas e metodológico da pesquisa avaliativa. Para a coleta de dados foram realizadas 38 entrevistas com profissionais de saúde e gestores; observação das atividades realizadas pelas equipes de saúde; e análise de 25 prontuários de pessoas que recebiam esse atendimento. A análise de dados teve auxílio do software ATLAS.ti, utilizando a técnica de análise de conteúdo dirigida. no âmbito micro, a assistência estava distante da integralidade das ações necessárias para assistir às pessoas com doença crônica e estava centrada no modelo biomédico. No âmbito meso, existia desarticulação entre os profissionais da Estratégia Saúde da Família, destes com os usuários, família e comunidade. No âmbito macro, identificou-se ausência de estratégias diretivas para a implementação das políticas públicas para o diabetes na prática assistencial. a implementação do Modelo de Atenção às Condições Crônicas constitui um grande desafio, necessitando, principalmente, de profissionais e gestores preparados para trabalharem com doenças crônicas e abertos a romperem com o modelo tradicional.

Service-Learning in Physical Education Teacher Training. Physical Education in the Modelo Prison, Barcelona

ERIC Educational Resources Information Center

Lleixà, Teresa; Ríos, Merche

2015-01-01

In the Psychiatric Unit of the Modelo Prison, Barcelona, a physical education programme is carried out annually with the participation of University of Barcelona (UB) students. In this context, we carried out a study based on service-learning parameters. The aim of the study was twofold: to determine the impact on inmates of the physical education…

Líneas metálicas en protuberancias solares

NASA Astrophysics Data System (ADS)

Stenborg, G.; Rovira, M. G.; Mauas, P.

Para determinar cual de los modelos existentes de protuberancias solares explica mejor las observaciones, es necesario, no solo ajustar los perfiles de las líneas de hidrógeno, sino también utilizar perfiles de distintos metales. En este trabajo, utilizamos un código desarrollado especialmente para calcular el equilibrio estadístico de cualquier especie atómica, aplicándolo al cálculo de los perfiles de las líneas del Ca II, el Mg II y el He, para determinar cómo se comportan ante variaciones en los parámetros de los modelos de protuberancia (ancho, presión y temperatura centrales y número de hebras), y comparamos con las observaciones existentes para determinar que modelo las ajusta mejor.

Low prevalence of Plasmodium and absence of malaria transmission in Conakry, Guinea: prospects for elimination.

PubMed

Kouassi, Bernard L; de Souza, Dziedzom K; Goepogui, Andre; Balde, Siradiou M; Diakité, Lamia; Sagno, Arsène; Djameh, Georgina I; Chammartin, Frédérique; Vounatsou, Penelope; Bockarie, Moses J; Utzinger, Jürg; Koudou, Benjamin G

2016-03-18

Over the past 15 years, mortality and morbidity due to malaria have been reduced substantially in sub-Saharan Africa and local elimination has been achieved in some settings. This study addresses the bio-ecology of larval and adult stages of malaria vectors, Plasmodium infection in Anopheles gambiae s.l. in the city of Conakry, Guinea, and discusses the prospect for malaria elimination. Water bodies were prospected to identify potential mosquito breeding sites for 6 days each in the dry season (January 2013) and in the rainy season (August 2013), using the dipping method. Adult mosquitoes were collected in 15 communities in the five districts of Conakry using exit traps and indoor spraying catches over a 1-year period (November 2012 to October 2013). Molecular approaches were employed for identification of Anopheles species, including An. coluzzii and An. gambiae s.s. Individual An. gambiae mosquitoes were tested for Plasmodium falciparum and P. vivax sporozoites using the VecTest™ malaria panel assay and an enzyme-linked immunosorbent assay. A systematic research of Ministry of Health statistical yearbooks was performed to determine malaria prevalence in children below the age of 5 years. Culex larval breeding sites were observed in large numbers throughout Conakry in both seasons. While Anopheles larval breeding sites were less frequent than Culex breeding sites, there was a high odds of finding An. gambiae mosquito larvae in agricultural sites during the rainy season. Over the 1-year study period, a total of 14,334 adult mosquitoes were collected; 14,135 Culex (98.6%) and 161 (1.1%) from the An. gambiae complex. One-hundred and twelve Anopheles mosquitoes, mainly collected from rice fields and gardens, were subjected to molecular analysis. Most of the mosquitoes were An. gambiae s.s. (n = 102; 91.1%) while the remaining 10 (8.9%) were An. melas. The molecular M form of An. gambiae s.s. was predominant (n = 89; 79.5%). The proportions of kdr genotype in the An. gambiae s.s. M and S form were 65.2 and 81.8% (n = 9), respectively. No sporozoite infection were detected in any of the mosquitoes tested. The prevalence of Plasmodium recorded in children aged below 5 years was relatively low and varied between 2.2 and 7.6% from 2009 to 2012. The low density of larval and adult stages of Anopheles mosquitoes, the absence of infected An. gambiae species and the low prevalence of Plasmodium in under 5-year-old children are important features that might facilitate malaria elimination in Conakry. The heterogeneity in species composition and resistance profiles call for vector control interventions that are tailored to the local bio-ecological setting.

Outline of a novel architecture for cortical computation.

PubMed

Majumdar, Kaushik

2008-03-01

In this paper a novel architecture for cortical computation has been proposed. This architecture is composed of computing paths consisting of neurons and synapses. These paths have been decomposed into lateral, longitudinal and vertical components. Cortical computation has then been decomposed into lateral computation (LaC), longitudinal computation (LoC) and vertical computation (VeC). It has been shown that various loop structures in the cortical circuit play important roles in cortical computation as well as in memory storage and retrieval, keeping in conformity with the molecular basis of short and long term memory. A new learning scheme for the brain has also been proposed and how it is implemented within the proposed architecture has been explained. A few mathematical results about the architecture have been proposed, some of which are without proof.

Water utilization, evapotranspiration and soil moisture monitoring in the south east region of south Australia

NASA Technical Reports Server (NTRS)

Mccloy, K. R.; Shepherd, K. J.; Mcintosh, G. F. (Principal Investigator)

1977-01-01

The author has identified the following significant results. It was established that reliable estimates of sand and coastal scrub areas can be determined from LANDSAT image classification by the Vec classifier more economically than by conventional means from a map of the coastal zone produced by photointerpretation using 1:10,000 aerial photography. Current LANDSAT imagery is also suitable for monitoring for large scale storm damage to the zone, but the normal change in sand areas extent due to man's activity or other reasons, is about 5 to 10 m per year, occasionally being as great as 30 m per year, so that it is considered that LANDSAT D will have the resolution necessary to monitor these changes but not current imagery.

INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY: Branch Processes of Vortex Filaments and Hopf Invariant Constraint on Scroll Wave

NASA Astrophysics Data System (ADS)

Zhu, Tao; Ren, Ji-Rong; Mo, Shu-Fan

2009-12-01

In this paper, by making use of Duan's topological current theory, the evolution of the vortex filaments in excitable media is discussed in detail. The vortex filaments are found generating or annihilating at the limit points and encountering, splitting, or merging at the bifurcation points of a complex function Z(vec x, t). It is also shown that the Hopf invariant of knotted scroll wave filaments is preserved in the branch processes (splitting, merging, or encountering) during the evolution of these knotted scroll wave filaments. Furthermore, it also revealed that the “exclusion principle" in some chemical media is just the special case of the Hopf invariant constraint, and during the branch processes the “exclusion principle" is also protected by topology.

Is there any link between accreditation programs and the models of organizational excellence?

PubMed

Berssaneti, Fernando Tobal; Saut, Ana Maria; Barakat, Májida Farid; Calarge, Felipe Araujo

2016-01-01

To evaluate whether accredited health organizations perform better management practices than non-accredited ones. The study was developed in two stages: a literature review, and a study of multiple cases in 12 healthcare organizations in the state of São Paulo, Brazil. It surveyed articles comparing hospital accreditation with the EFQM (European Foundation for Quality Management) model of excellence in management. According to the pertinent literature, the accreditation model and the EFQM model are convergent and supplementary in some aspects. With 99% confidence, one can say that there is evidence that accredited organizations scored better in the evaluation based on the EFQM model in comparison to non-accredited organizations. This result was also confirmed in the comparison of results between the categories Facilitators and Results in the EFQM model. There is convergence between the accreditation model and the EFQM excellence model, suggesting that accreditation helps the healthcare sector to implement the best management practices already used by other business sectors. Avaliar se as organizações de saúde acreditadas possuem melhores práticas de gestão do que as não acreditadas. A pesquisa foi dividida em duas etapas: revisão da literatura e estudo de casos múltiplos com 12 organizações de saúde, localizadas no estado de São Paulo ‒ Brasil. Foram pesquisados artigos que comparavam a acreditação hospitalar com o modelo de excelência em gestão da EFQM (European Foundation for Quality Management), sendo que a literatura pertinente considera que o modelo de acreditação e o modelo da EFQM são convergentes e, ao mesmo tempo, complementares em determinados aspectos. Com 99% de confiança, pode-se afirmar que há evidência de que as organizações com acreditação obtiveram uma pontuação maior na avaliação baseada no modelo EFQM comparativamente às organizações não acreditadas. Este resultado também se confirmou na comparação dos resultados das categorias Facilitadores e Resultados do modelo EFQM. Há uma convergência entre o modelo de acreditação e o modelo de excelência da EFQM, sugerindo que a acreditação contribui para o setor de saúde implementar as melhores práticas de gestão já difundidas em outros setores de negócio.

Concepciones Alternativas de "Fotosintesis" en estudiantes Universitarios del curso basico de Biologia y posibles correcciones con el Modelo Educativo MODEF

NASA Astrophysics Data System (ADS)

De Jesus Roman, Sandra

Concepciones Alternativas de Fotosíntesis en estudiantes Universitariosdel curso básico de Biología y posibles correcciones con el Modelo Educativo MODEF El modelo educativo para la enseñanza de Fotosíntesis (MODEF) se implantó para trabajar el problema de las concepciones alternativas (CA) en un curso de Biología General. Se evaluaron los resultados en cuanto al logro del aprendizaje significativo. La pregunta central de la investigación fue: ¿Cómo aporta el modelo educativo en la didáctica y comprensión del tema de fotosíntesis? Se efectuó una investigación acción con una fase cuantitativa y una cualitativa. Para la fase cuantitativa se elaboró una prueba para determinar las concepciones alternativas, se validó y se sometió a los estudiantes que participaron en el estudio antes y después de ofrecer la unidad de metabolismo celular. Los participantes eran estudiantes de primer año de la Universidad de Puerto Rico en Bayamón (UPRB). Se llevó a cabo un análisis de consistencia interna de la prueba mediante el método Alfa de Cronbach. Se analizaron las contestaciones a cada pregunta mediante la prueba de Ji cuadrado de contingencia, se efectuó la prueba de t y el coeficiente r de Pearson. La fase cualitativa incluyó la observación participativa de la investigadora- profesora, las reflexiones de los estudiantes y la información de las entrevistas semi-estructuradas que se realizaron a tres estudiantes del curso. El análisis se llevó a cabo mediante el Modelo de Wolcott. Se trabajaron diez CA de las cuales siete fueron corregidas mediante el Modelo MODEF. Las actividades más importantes para el proceso de aprendizaje incluyeron el trabajo de investigación o búsqueda de información para hacer una presentación digital, la elaboración de tablas, los mapas de conceptos, el uso de visuales o videos y las analogías para explicar conceptos o procesos. En conclusión: se recomienda el uso del Modelo MODEF para la discusión del tema de Fotosíntesis a base de los resultados cuantitativos y cualitativos de esta investigación. El Comité Institucional para la Protección de los Seres Humanos en la Investigación (CIPSHI) autorizó el estudio.

NOAA Weather Radio

Science.gov Websites

unidades portátiles portátiles que atiende clima radiofónicas, a los modelos de escritorio y consola que específica o modelo del receptor. Las listas siguientes, que contienen algunos de los muchos NOAA Weather , dependiendo del número de características incluidas. Multi-multi-Band/función de receptores: los receptores

Descripción de la zona de alta difusión en un modelo bidimensional para hojas de corriente

NASA Astrophysics Data System (ADS)

Montero, M. F.; Paola, C. A.; Platzeck, A. M.

Los modelos bidimensionales para describir hojas de corriente de alta simetría no suministran una descripción detallada de las regiones donde la difusión es considerablemente importante. Tal es el caso de los modelos desarrollados en la década del '60 por Sweet, Parker, Petschek y Sonnerup. En esta comunicación presentamos una solución de las ecuaciones MHD en el entorno del origen, construyendo series bidimensionales para todas las magnitudes físicas involucradas. Valiéndonos de la alta simetría y de las características del problema, logramos reducir el número de coeficientes a calcular. Utilizamos un programa autoconsistente para extender el cálculo a regiones vecinas con difusión moderada o despreciable.

Tuning complexity by lithiation: A family of intergrowth structures using condensed hypho-icosahedra in the Li-doped Ca–Zn system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Qisheng; Zhu, Ran; Miller, Gordon J.

Cluster chemistry of intermetallics with valence electron counts (VECs) in the range of 2.0–3.0 is intriguing. Lithiation of polar intermetallics in this VEC region is found to be an effective chemical route to produce new complex structures with different stability mechanisms. In this work, two new complex intermetallic structures have been discovered in the Ca–Li–Zn system: Ca 12Li xZn 59–x and Ca 15Li xZn 75–x. Ca 12Li xZn 59–x, x ≈ 5.65(3)–14.95(3), forms in the trigonal space group R3m, with a = 9.074(1)–9.1699(2) Å, c = 53.353(1)–53.602(1) Å, and Z = 3. In comparison, Ca 15Li xZn 75–x, x ≈more » 19.07(2), crystallizes in the space group P6 3/ mmc, with a ≈ 9.183(1) Å, c ≈ 45.191(5) Å), and Z = 2. Both structures are members of a large intergrowth family featuring slabs of dimers (D) and trimers (T) stacking along [001], with the sequences DTDDTDDTD for Ca 12Li xZn 59–x and TDDDTDDD for Ca 15Li xZn 75–x. Each dimer consists of two face-sharing Zn-centered hypho-icosahedra, and each trimer comprises a Li-centered icosahedron sandwiched by two hypho-icosahedra. Furthermore, this intergrowth family includes several known intermetallic structure types involving very electropositive metals, e.g., SrMg 5.2, Ba 2Li 4.21Al 4.79, and Sr 9Li 17.5Al 25.5. Because of cluster defects and condensation, both Ca 12Li xZn 59–x and Ca 15Li xZn 75–x are electronically akin to close-packed metals, and their structural stabilities can be interpreted by a Hume-Rothery mechanism rather than the Zintl–Klemm concept.« less

Unified halo-independent formalism from convex hulls for direct dark matter searches

NASA Astrophysics Data System (ADS)

Gelmini, Graciela B.; Huh, Ji-Haeng; Witte, Samuel J.

2017-12-01

Using the Fenchel-Eggleston theorem for convex hulls (an extension of the Caratheodory theorem), we prove that any likelihood can be maximized by either a dark matter 1- speed distribution F(v) in Earth's frame or 2- Galactic velocity distribution fgal(vec u), consisting of a sum of delta functions. The former case applies only to time-averaged rate measurements and the maximum number of delta functions is (Script N‑1), where Script N is the total number of data entries. The second case applies to any harmonic expansion coefficient of the time-dependent rate and the maximum number of terms is Script N. Using time-averaged rates, the aforementioned form of F(v) results in a piecewise constant unmodulated halo function tilde eta0BF(vmin) (which is an integral of the speed distribution) with at most (Script N-1) downward steps. The authors had previously proven this result for likelihoods comprised of at least one extended likelihood, and found the best-fit halo function to be unique. This uniqueness, however, cannot be guaranteed in the more general analysis applied to arbitrary likelihoods. Thus we introduce a method for determining whether there exists a unique best-fit halo function, and provide a procedure for constructing either a pointwise confidence band, if the best-fit halo function is unique, or a degeneracy band, if it is not. Using measurements of modulation amplitudes, the aforementioned form of fgal(vec u), which is a sum of Galactic streams, yields a periodic time-dependent halo function tilde etaBF(vmin, t) which at any fixed time is a piecewise constant function of vmin with at most Script N downward steps. In this case, we explain how to construct pointwise confidence and degeneracy bands from the time-averaged halo function. Finally, we show that requiring an isotropic Galactic velocity distribution leads to a Galactic speed distribution F(u) that is once again a sum of delta functions, and produces a time-dependent tilde etaBF(vmin, t) function (and a time-averaged tilde eta0BF(vmin)) that is piecewise linear, differing significantly from best-fit halo functions obtained without the assumption of isotropy.

Transplantation of Endothelial Cells to Mitigate Acute and Chronic Radiation Injury to Vital Organs.

PubMed

Rafii, Shahin; Ginsberg, Michael; Scandura, Joseph; Butler, Jason M; Ding, Bi-Sen

2016-08-01

Current therapeutic approaches for treatment of exposure to radiation involve the use of antioxidants, chelating agents, recombinant growth factors and transplantation of stem cells (e.g., hematopoietic stem cell transplantation). However, exposure to high-dose radiation is associated with severe damage to the vasculature of vital organs, often leading to impaired healing, tissue necrosis, thrombosis and defective regeneration caused by aberrant fibrosis. It is very unlikely that infusion of protective chemicals will reverse severe damage to the vascular endothelial cells (ECs). The role of irradiated vasculature in mediating acute and chronic radiation syndromes has not been fully appreciated or well studied. New approaches are necessary to replace and reconstitute ECs in organs that are irreversibly damaged by radiation. We have set forth the novel concept that ECs provide paracrine signals, also known as angiocrine signals, which not only promote healing of irradiated tissue but also direct organ regeneration without provoking fibrosis. We have developed innovative technologies that enable manufacturing and banking of human GMP-grade ECs. These ECs can be transplanted intravenously to home to and engraft to injured tissues where they augment organ repair, while preventing maladaptive fibrosis. In the past, therapeutic transplantation of ECs was not possible due to a shortage of availability of suitable donor cell sources and preclinical models, a lack of understanding of the immune privilege of ECs, and inadequate methodologies for expansion and banking of engraftable ECs. Recent advances made by our group as well as other laboratories have breached the most significant of these obstacles with the development of technologies to manufacture clinical-scale quantities of GMP-grade and human ECs in culture, including genetically diverse reprogrammed human amniotic cells into vascular ECs (rAC-VECs) or human pluripotent stem cells into vascular ECs (iVECs). This approach provides a path to therapeutic EC transplantation that can be infused concomitantly or sequentially with hematopoietic stem cell transplantation more than 24 h after irradiation to support multi-organ regeneration, thereby improving immediate and long-term survival, while limiting long-term morbidity resulting from nonregenerative damage repair pathways.

miR-181b regulates vascular stiffness age dependently in part by regulating TGF-β signaling

PubMed Central

Hori, Daijiro; Dunkerly-Eyring, Brittany; Nomura, Yohei; Biswas, Debjit; Steppan, Jochen; Henao-Mejia, Jorge; Adachi, Hideo; Santhanam, Lakshmi; Berkowitz, Dan E.; Steenbergen, Charles; Flavell, Richard A.

2017-01-01

Background Endothelial dysfunction and arterial stiffening play major roles in cardiovascular diseases. The critical role for the miR-181 family in vascular inflammation has been documented. Here we tested whether the miR-181 family can influence the pathogenesis of hypertension and vascular stiffening. Methods and results qPCR data showed a significant decrease in miR-181b expression in the aorta of the older mice. Eight miR-181a1/b1-/- mice and wild types (C57BL6J:WT) were followed weekly for pulse wave velocity (PWV) and blood pressure measurements. After 20 weeks, the mice were tested for endothelial function and aortic modulus. There was a progressive increase in PWV and higher systolic blood pressure in miR-181a1/b1-/- mice compared with WTs. At 21 weeks, aortic modulus was significantly greater in the miR-181a1/b1-/- group, and serum TGF-β was found to be elevated at this time. A luciferase reporter assay confirmed miR-181b targets TGF-βi (TGF-β induced) in the aortic VSMCs. In contrast, wire myography revealed unaltered endothelial function along with higher nitric oxide production in the miR-181a1/b1-/- group. Cultured VECs and VSMCs from the mouse aorta showed more secreted TGF-β in VSMCs of the miR-181a1/b1-/- group; whereas, no change was observed from VECs. Circulating levels of angiotensin II were similar in both groups. Treatment with losartan (0.6 g/L) prevented the increase in PWV, blood pressure, and vascular stiffness in miR-181a1/b1-/- mice. Immunohistochemistry and western blot for p-SMAD2/3 validated the inhibitory effect of losartan on TGF-β signaling in miR-181a1/b1-/- mice. Conclusions Decreased miR-181b with aging plays a critical role in ECM remodeling by removing the brake on the TGF-β, pSMAD2/3 pathway. PMID:28323879

Tuning complexity by lithiation: A family of intergrowth structures using condensed hypho-icosahedra in the Li-doped Ca–Zn system

DOE PAGES

Lin, Qisheng; Zhu, Ran; Miller, Gordon J.

2016-04-26

Cluster chemistry of intermetallics with valence electron counts (VECs) in the range of 2.0–3.0 is intriguing. Lithiation of polar intermetallics in this VEC region is found to be an effective chemical route to produce new complex structures with different stability mechanisms. In this work, two new complex intermetallic structures have been discovered in the Ca–Li–Zn system: Ca 12Li xZn 59–x and Ca 15Li xZn 75–x. Ca 12Li xZn 59–x, x ≈ 5.65(3)–14.95(3), forms in the trigonal space group R3m, with a = 9.074(1)–9.1699(2) Å, c = 53.353(1)–53.602(1) Å, and Z = 3. In comparison, Ca 15Li xZn 75–x, x ≈more » 19.07(2), crystallizes in the space group P6 3/ mmc, with a ≈ 9.183(1) Å, c ≈ 45.191(5) Å), and Z = 2. Both structures are members of a large intergrowth family featuring slabs of dimers (D) and trimers (T) stacking along [001], with the sequences DTDDTDDTD for Ca 12Li xZn 59–x and TDDDTDDD for Ca 15Li xZn 75–x. Each dimer consists of two face-sharing Zn-centered hypho-icosahedra, and each trimer comprises a Li-centered icosahedron sandwiched by two hypho-icosahedra. Furthermore, this intergrowth family includes several known intermetallic structure types involving very electropositive metals, e.g., SrMg 5.2, Ba 2Li 4.21Al 4.79, and Sr 9Li 17.5Al 25.5. Because of cluster defects and condensation, both Ca 12Li xZn 59–x and Ca 15Li xZn 75–x are electronically akin to close-packed metals, and their structural stabilities can be interpreted by a Hume-Rothery mechanism rather than the Zintl–Klemm concept.« less

Ecological significance of residual exposures and effects from the Exxon Valdez oil spill.

PubMed

Harwell, Mark A; Gentile, John H

2006-07-01

An ecological significance framework is used to assess the ecological condition of Prince William Sound (PWS), Alaska, USA, in order to address the current management question: 17 y following the Exxon Valdez oil spill (EVOS), are there any remaining and continuing ecologically significant exposures or effects on the PWS ecosystem caused by EVOS? We examined the extensive scientific literature funded by the Exxon Valdez Trustees or by ExxonMobil to assess exposures and effects from EVOS. Criteria to assess ecological significance include whether a change in a valued ecosystem component (VEC) is sufficient to affect the structure, function, and/or health of the system and whether such a change exceeds natural variability. The EVOS occurred on 24 March 1989, releasing over 250,000 barrels of crude oil into PWS. Because PWS is highly dynamic, the residual oil was largely eliminated in the first few years, and now only widely dispersed, highly weathered, or isolated small pockets of residual contamination remain. Many other sources of polycyclic aromatic hydrocarbons (PAHs) exist in PWS from past or present human activities or natural oil seeps. Multiple-lines-of-evidence analyses indicate that residual PAHs from EVOS no longer represent an ecologically significant exposure risk to PWS. To assess the ecological significance of any residual effects from EVOS, we examined the literature on more than 20 VECs, including primary producers, filter feeders, fish and bird primary consumers, fish and bird top predators, a bird scavenger, mammalian primary consumers and top predators, biotic communities, ecosystem-level properties of trophodynamics and biogeochemical processes, and landscape-level properties of habitat mosaic and wilderness quality. None of these has any ecologically significant effects that are detectable at present, with the exception of 1 pod of orcas and possibly 1 subpopulation of sea otters; however, in both those cases, PWS-wide populations appear to have fully recovered. Many other stressors continue to affect PWS adversely, including climate and oceanographic variability, increased tourism and shipping, invasive species, the 1964 earthquake, and overexploitation of marine resources, with associated cascading effects on populations of PWS fish and predators. We conclude that the PWS ecosystem has now effectively recovered from EVOS.

miR-181b regulates vascular stiffness age dependently in part by regulating TGF-β signaling.

PubMed

Hori, Daijiro; Dunkerly-Eyring, Brittany; Nomura, Yohei; Biswas, Debjit; Steppan, Jochen; Henao-Mejia, Jorge; Adachi, Hideo; Santhanam, Lakshmi; Berkowitz, Dan E; Steenbergen, Charles; Flavell, Richard A; Das, Samarjit

2017-01-01

Endothelial dysfunction and arterial stiffening play major roles in cardiovascular diseases. The critical role for the miR-181 family in vascular inflammation has been documented. Here we tested whether the miR-181 family can influence the pathogenesis of hypertension and vascular stiffening. qPCR data showed a significant decrease in miR-181b expression in the aorta of the older mice. Eight miR-181a1/b1-/- mice and wild types (C57BL6J:WT) were followed weekly for pulse wave velocity (PWV) and blood pressure measurements. After 20 weeks, the mice were tested for endothelial function and aortic modulus. There was a progressive increase in PWV and higher systolic blood pressure in miR-181a1/b1-/- mice compared with WTs. At 21 weeks, aortic modulus was significantly greater in the miR-181a1/b1-/- group, and serum TGF-β was found to be elevated at this time. A luciferase reporter assay confirmed miR-181b targets TGF-βi (TGF-β induced) in the aortic VSMCs. In contrast, wire myography revealed unaltered endothelial function along with higher nitric oxide production in the miR-181a1/b1-/- group. Cultured VECs and VSMCs from the mouse aorta showed more secreted TGF-β in VSMCs of the miR-181a1/b1-/- group; whereas, no change was observed from VECs. Circulating levels of angiotensin II were similar in both groups. Treatment with losartan (0.6 g/L) prevented the increase in PWV, blood pressure, and vascular stiffness in miR-181a1/b1-/- mice. Immunohistochemistry and western blot for p-SMAD2/3 validated the inhibitory effect of losartan on TGF-β signaling in miR-181a1/b1-/- mice. Decreased miR-181b with aging plays a critical role in ECM remodeling by removing the brake on the TGF-β, pSMAD2/3 pathway.

Determinación de temperatura efectiva y gravedad superficial de estrellas B y A de secuencia principal

NASA Astrophysics Data System (ADS)

Nieva, M. F.; Pintado, O. I.; Adelman, S.; Rayle, K. E.; Sanders, S. E., Jr.

Las temperaturas efectivas (Teff) y gravedades superficiales (log g) de un grupo de estrellas de tipo B y A de Secuencia Principal se determinaron en varias etapas. En una primera aproximación se usaron los índices fotométricos de Strömgren para realizar el cálculo con el programa de Napiwotski et al.(1993). Luego se hizo un ajuste comparando datos espectrofotométricos con flujos obtenidos con el modelo ATLAS9 en la región visible. Y a continuación se hizo un mejor ajuste comparando los perfiles de la línea Hγ con espectros sintéticos calculados con SYNTHE. Además, se analizó el efecto de usar el modelo de Canuto y Mazzitelli (1991), donde se considera The Mixing Length Theory, en modelos de atmósferas de estrellas.

Realization of Chinese word segmentation based on deep learning method

NASA Astrophysics Data System (ADS)

Wang, Xuefei; Wang, Mingjiang; Zhang, Qiquan

2017-08-01

In recent years, with the rapid development of deep learning, it has been widely used in the field of natural language processing. In this paper, I use the method of deep learning to achieve Chinese word segmentation, with large-scale corpus, eliminating the need to construct additional manual characteristics. In the process of Chinese word segmentation, the first step is to deal with the corpus, use word2vec to get word embedding of the corpus, each character is 50. After the word is embedded, the word embedding feature is fed to the bidirectional LSTM, add a linear layer to the hidden layer of the output, and then add a CRF to get the model implemented in this paper. Experimental results show that the method used in the 2014 People's Daily corpus to achieve a satisfactory accuracy.

Stochastic nonlinear time series forecasting using time-delay reservoir computers: performance and universality.

PubMed

Grigoryeva, Lyudmila; Henriques, Julie; Larger, Laurent; Ortega, Juan-Pablo

2014-07-01

Reservoir computing is a recently introduced machine learning paradigm that has already shown excellent performances in the processing of empirical data. We study a particular kind of reservoir computers called time-delay reservoirs that are constructed out of the sampling of the solution of a time-delay differential equation and show their good performance in the forecasting of the conditional covariances associated to multivariate discrete-time nonlinear stochastic processes of VEC-GARCH type as well as in the prediction of factual daily market realized volatilities computed with intraday quotes, using as training input daily log-return series of moderate size. We tackle some problems associated to the lack of task-universality for individually operating reservoirs and propose a solution based on the use of parallel arrays of time-delay reservoirs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Melhoramentos no código Wilson-Devinney para binárias eclipsantes

NASA Astrophysics Data System (ADS)

Vieira, L. A.; Vaz, L. P. R.

2003-08-01

A análise de curvas de luz e velocidades radiais de sistemas binários eclipsantes pode ser feita por meio de vários modelos. Um desses é o Modelo Wilson-Devinney (WD). Ao longo dos anos, esse modelo sofreu várias alterações em seus códigos principais, com a finalidade de torná-lo mais consistente tanto fíisica como numericamente. O Modelo WD tem sido melhorado de várias maneiras em seus dois códigos: um para a predição das curvas de luz teórica e de velocidade radiais e outra para as soluções destas curvas. Teoricamente, na física do modelo, nós introduzimos a possibilidade de levar em conta os efeitos do movimento apsidal. Numericamente, nós introduzimos a possibilidade de usar o Método SIMPLEX no procedimento da solução, como uma alternativa para o já implementado Método de Mínimos Quadrados (Least Squares Method). Estas modificações, juntamente com outras já introduzidas pelo nosso grupo anteriormente, tornam o código mais eficiente na solução das curvas de luz e de velocidade radiais de binárias eclipsantes. Como o modelo tem sido usado para analisar sistemas com componentes pré-sequência principal (TY CrA, Casey et al. 1998, Vaz et al. 1998), SM 790, Stassun et al. 2003), este melhoramento beneficiará estes casos também. Apresentamos os resultados obtidos com a modificação do código WD por meio do uso de dados da estrela GL Carinae, comprovando, (1) que os parâmetros orbitais calculados por nós são coerentes com os obtidos anteriormente na literatura (Giménez & Clausen, 1986) e com os obtidos por Faria (1987), e (2) que a implementação do Método SIMPLEX torna o código mais lento mas completamente consistente internamente e evita os problemas gerados pelo uso do Método de Mínimos Quadrados, tais como imprecisão no cálculo das derivadas parciais e convergência para mínimos locais.

Are Bred Vectors The Same As Lyapunov Vectors?

NASA Astrophysics Data System (ADS)

Kalnay, E.; Corazza, M.; Cai, M.

Regional loss of predictability is an indication of the instability of the underlying flow, where small errors in the initial conditions (or imperfections in the model) grow to large amplitudes in finite times. The stability properties of evolving flows have been studied using Lyapunov vectors (e.g., Alligood et al, 1996, Ott, 1993, Kalnay, 2002), singular vectors (e.g., Lorenz, 1965, Farrell, 1988, Molteni and Palmer, 1993), and, more recently, with bred vectors (e.g., Szunyogh et al, 1997, Cai et al, 2001). Bred vectors (BVs) are, by construction, closely related to Lyapunov vectors (LVs). In fact, after an infinitely long breeding time, and with the use of infinitesimal ampli- tudes, bred vectors are identical to leading Lyapunov vectors. In practical applications, however, bred vectors are different from Lyapunov vectors in two important ways: a) bred vectors are never globally orthogonalized and are intrinsically local in space and time, and b) they are finite-amplitude, finite-time vectors. These two differences are very significant in a dynamical system whose size is very large. For example, the at- mosphere is large enough to have "room" for several synoptic scale instabilities (e.g., storms) to develop independently in different regions (say, North America and Aus- tralia), and it is complex enough to have several different possible types of instabilities (such as barotropic, baroclinic, convective, and even Brownian motion). Bred vectors share some of their properties with leading LVs (Corazza et al, 2001a, 2001b, Toth and Kalnay, 1993, 1997, Cai et al, 2001). For example, 1) Bred vectors are independent of the norm used to define the size of the perturba- tion. Corazza et al. (2001) showed that bred vectors obtained using a potential enstro- phy norm were indistinguishable from bred vectors obtained using a streamfunction squared norm, in contrast with singular vectors. 2) Bred vectors are independent of the length of the rescaling period as long as the perturbations remain approximately linear (for example, for atmospheric models the interval for rescaling could be varied between a single time step and 1 day without affecting qualitatively the characteristics of the bred vectors. However, the finite-amplitude, finite-time, and lack of orthogonalization of the BVs introduces important differences with LVs: 1) In regions that undergo strong instabilities, the bred vectors tend to be locally domi- 1 nated by simple, low-dimensional structures. Patil et al (2001) showed that the BV-dim (appendix) gives a good estimate of the number of dominant directions (shapes) of the local k bred vectors. For example, if half of them are aligned in one direction, and half in a different direction, the BV-dim is about two. If the majority of the bred vectors are aligned predominantly in one direction and only a few are aligned in a second direction, then the BV-dim is between 1 and 2. Patil et al., (2001) showed that the regions with low dimensionality cover about 20% of the atmosphere. They also found that these low-dimensionality regions have a very well defined vertical structure, and a typical lifetime of 3-7 days. The low dimensionality identifies regions where the in- stability of the basic flow has manifested itself in a low number of preferred directions of perturbation growth. 2) Using a Quasi-Geostrophic simulation system of data assimilation developed by Morss (1999), Corazza et al (2001a, b) found that bred vectors have structures that closely resemble the background (short forecasts used as first guess) errors, which in turn dominate the local analysis errors. This is especially true in regions of low dimensionality, which is not surprising if these are unstable regions where errors grow in preferred shapes. 3) The number of bred vectors needed to represent the unstable subspace in the QG system is small (about 6-10). This was shown by computing the local BV-dim as a function of the number of independent bred vectors. Convergence in the local dimen- sion starts to occur at about 6 BVs, and is essentially complete when the number of vectors is about 10-15 (Corazza et al, 2001a). This should be contrasted with the re- sults of Snyder and Joly (1998) and Palmer et al (1998) who showed that hundreds of Lyapunov vectors with positive Lyapunov exponents are needed to represent the attractor of the system in quasi-geostrophic models. 4) Since only a few bred vectors are needed, and background errors project strongly in the subspace of bred vectors, Corazza et al (2001b) were able to develop cost-efficient methods to improve the 3D-Var data assimilation by adding to the background error covariance terms proportional to the outer product of the bred vectors, thus represent- ing the "errors of the day". This approach led to a reduction of analysis error variance of about 40% at very low cost. 5) The fact that BVs have finite amplitude provides a natural way to filter out instabil- ities present in the system that have fast growth, but saturate nonlinearly at such small amplitudes that they are irrelevant for ensemble perturbations. As shown by Lorenz (1996) Lyapunov vectors (and singular vectors) of models including these physical phenomena would be dominated by the fast but small amplitude instabilities, unless they are explicitly excluded from the linearized models. Bred vectors, on the other 2 hand, through the choice of an appropriate size for the perturbation, provide a natural filter based on nonlinear saturation of fast but irrelevant instabilities. 6) Every bred vector is qualitatively similar to the *leading* LV. LVs beyond the leading LV are obtained by orthogonalization after each time step with respect to the previous LVs subspace. The orthogonalization requires the introduction of a norm. With an enstrophy norm, the successive LVs have larger and larger horizontal scales, and a choice of a stream function norm would lead to successively smaller scales in the LVs. Beyond the first few LVs, there is little qualitative similarity between the background errors and the LVs. In summary, in a system like the atmosphere with enough physical space for several independent local instabilities, BVs and LVs share some properties but they also have significant differences. BV are finite-amplitude, finite-time, and because they are not globally orthogonalized, they have local properties in space. Bred vectors are akin to the leading LV, but bred vectors derived from different arbitrary initial perturba- tions remain distinct from each other, instead of collapsing into a single leading vec- tor, presumably because the nonlinear terms and physical parameterizations introduce sufficient stochastic forcing to avoid such convergence. As a result, there is no need for global orthogonalization, and the number of bred vectors required to describe the natural instabilities in an atmospheric system (from a local point of view) is much smaller than the number of Lyapunov vectors with positive Lyapunov exponents. The BVs are independent of the norm, whereas the LVs beyond the first one do depend on the choice of norm: for example, they become larger in scale with a vorticity norm, and smaller with a stream function norm. These properties of BVs result in significant advantages for data assimilation and en- semble forecasting for the atmosphere. Errors in the analysis have structures very similar to bred vectors, and it is found that they project very strongly on the subspace of a few bred vectors. This is not true for either Lyapunov vectors beyond the lead- ing LVs, or for singular vectors unless they are constructed with a norm based on the analysis error covariance matrix (or a bred vector covariance). The similarity between bred vectors and analysis errors leads to the ability to include "errors of the day" in the background error covariance and a significant improvement of the analysis beyond 3D-Var at a very low cost (Corazza, 2001b). References Alligood K. T., T. D. Sauer and J. A. Yorke, 1996: Chaos: an introduction to dynamical systems. Springer-Verlag, New York. Buizza R., J. Tribbia, F. Molteni and T. Palmer, 1993: Computation of optimal unstable 3 structures for numerical weather prediction models. Tellus, 45A, 388-407. Cai, M., E. Kalnay and Z. Toth, 2001: Potential impact of bred vectors on ensemble forecasting and data assimilation in the Zebiak-Cane model. Submitted to J of Climate. Corazza, M., E. Kalnay, D. J. Patil, R. Morss, M. Cai, I. Szunyogh, B. R. Hunt, E. Ott and J. Yorke, 2001: Use of the breeding technique to determine the structure of the "errors of the day". Submitted to Nonlinear Processes in Geophysics. Corazza, M., E. Kalnay, DJ Patil, E. Ott, J. Yorke, I Szunyogh and M. Cai, 2001: Use of the breeding technique in the estimation of the background error covariance matrix for a quasigeostrophic model. AMS Symposium on Observations, Data Assimilation and Predictability, Preprints volume, Orlando, FA, 14-17 January 2002. Farrell, B., 1988: Small error dynamics and the predictability of atmospheric flow, J. Atmos. Sciences, 45, 163-172. Kalnay, E 2002: Atmospheric modeling, data assimilation and predictability. Chapter 6. Cambridge University Press, UK. In press. Kalnay E and Z Toth 1994: Removing growing errors in the analysis. Preprints, Tenth Conference on Numerical Weather Prediction, pp 212-215. Amer. Meteor. Soc., July 18-22, 1994. Lorenz, E.N., 1965: A study of the predictability of a 28-variable atmospheric model. Tellus, 21, 289-307. Lorenz, E.N., 1996: Predictability- A problem partly solved. Proceedings of the ECMWF Seminar on Predictability, Reading, England, Vol. 1 1-18. Molteni F. and TN Palmer, 1993: Predictability and finite-time instability of the north- ern winter circulation. Q. J. Roy. Meteorol. Soc. 119, 269-298. Morss, R.E.: 1999: Adaptive observations: Idealized sampling strategies for improving numerical weather prediction. Ph.D. Thesis, Massachussetts Institute of Technology, 225pp. Ott, E., 1993: Chaos in Dynamical Systems. Cambridge University Press. New York. Palmer, TN, R. Gelaro, J. Barkmeijer and R. Buizza, 1998: Singular vectors, metrics and adaptive observations. J. Atmos Sciences, 55, 633-653. Patil, DJ, BR Hunt, E Kalnay, J. Yorke, and E. Ott, 2001: Local low dimensionality of atmospheric dynamics. Phys. Rev. Lett., 86, 5878. Patil, DJ, I. Szunyogh, BR Hunt, E Kalnay, E Ott, and J. Yorke, 2001: Using large 4 member ensembles to isolate local low dimensionality of atmospheric dynamics. AMS Symposium on Observations, Data Assimilation and Predictability, Preprints volume, Orlando, FA, 14-17 January 2002. Snyder, C. and A. Joly, 1998: Development of perturbations within growing baroclinic waves. Q. J. Roy. Meteor. Soc., 124, pp 1961. Szunyogh, I, E. Kalnay and Z. Toth, 1997: A comparison of Lyapunov and Singular vectors in a low resolution GCM. Tellus, 49A, 200-227. Toth, Z and E Kalnay 1993: Ensemble forecasting at NMC - the generation of pertur- bations. Bull. Amer. Meteorol. Soc., 74, 2317-2330. Toth, Z and E Kalnay 1997: Ensemble forecasting at NCEP and the breeding method. Mon Wea Rev, 125, 3297-3319. * Corresponding author address: Eugenia Kalnay, Meteorology Depart- ment, University of Maryland, College Park, MD 20742-2425, USA; email: ekalnay@atmos.umd.edu Appendix: BV-dimension Patil et al., (2001) defined local bred vectors around a point in the 3-dimensional grid of the model by taking the 24 closest horizontal neighbors. If there are k bred vectors available, and N model variables for each grid point, the k local bred vectors form the columns of a 25Nxk matrix B. The kxk covariance matrix is C=B^T B. Its eigen- values are positive, and its eigenvectors v(i) are the singular vectors of the local bred vector subspace. The Bred Vector dimension (BV-dim) measures the local effective dimension: BV-dim[s,s,...,s(k)]={SUM[s(i)]}^2/SUM[s(i)]^2 where s(i) are the square roots of the eigenvalues of the covariance matrix. 5

Estudo de não gaussianidade nas anisotropias da RCF medidas Wmap

NASA Astrophysics Data System (ADS)

Andrade, A. P. A.; Wuensche, C. A.; Ribeiro, A. L. B.

2003-08-01

A investigação do campo de flutuações da Radiação Cósmica de Fundo (RCF) pode oferecer um importante teste para os modelos cosmológicos que descrevem a origem e a evolução das flutuações primordiais. De um lado, apresenta-se o modelo inflacionário que prevê um espectro de flutuações adiabáticas distribuídas segundo uma gaussiana e, de outro, os modelos de defeitos topológicos (dentre outros) que descrevem um mecanismo para a geração de flutuações de isocurvatura que obedecem a uma distribuição não gaussiana. Este trabalho tem como objetivo caracterizar traços do modelo não gaussiano de campo misto (entre flutuações adiabáticas e de isocurvatura) nos mapas do Wilkinson Microwave Anisotropy Probe (WMAP). Simulações das anisotropias da RCF no contexto de mistura indicam traços marcantes na distribuição das flutuações de temperatura, mesmo quando consideradas pequenas contribuições do campo de isocurvatura (da ordem de 0.001). O efeito da mistura entre os campos resulta na transferência de potência de flutuações em escalas angulares intermediárias para flutuações em pequenas escalas angulares. Este efeito pode ser caracterizado pela relação entre as amplitudes dos primeiros picos acústicos no espectro de potência da RCF. Neste trabalho, investigamos a contribuição do campo de isocurvatura, no contexto de mistura, sobre as observações recentes da RCF realizadas pelo WMAP. As previsões do modelo de campo misto, uma vez confrontadas com as observações em pequenas escalas angulares, podem ajudar a revelar a natureza das flutuações primordiais.

Readiness to tackle chronicity in Spanish health care organisations: a two-year experience with the Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations instrument

PubMed Central

Mira, José Joaquín; Fernández-Cano, Paloma; Contel, Joan Carlos; Guilabert-Mora, Mercedes; Solas-Gaspar, Olga

2015-01-01

Introduction: The Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations instrument was developed to implement the conceptual framework of the Chronic Care Model in the Spanish national health system. It has been used to assess readiness to tackle chronicity in health care organisations. In this study, we use self-assessments at macro-, meso- and micro-management levels to (a) describe the two-year experience with the Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations tool in Spain and (b) assess the validity and reliability of this instrument. Methods: The results from 55 organisational self-assessments were included and described. In addition to that, the internal consistency, reliability and construct validity of Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations were examined using Cronbach's alpha, the Spearman–Brown coefficient and factorial analysis. Results: The obtained scores reflect opportunities for improvement in all dimensions of the instrument. Cronbach's alpha ranged between 0.90 and 0.95 and the Spearman–Brown coefficient ranged between 0.77 and 0.94. All 27 components converged in a second-order factorial solution that explained 53.8% of the total variance, with factorial saturations for the components of between 0.57 and 0.94. Conclusions: Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations is an instrument that allows health care organisations to perform self-assessments regarding their readiness to tackle chronicity and to identify areas for improvement in chronic care. PMID:27118958

Readiness to tackle chronicity in Spanish health care organisations: a two-year experience with the Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations instrument.

PubMed

Mira, José Joaquín; Nuño-Solinís, Roberto; Fernández-Cano, Paloma; Contel, Joan Carlos; Guilabert-Mora, Mercedes; Solas-Gaspar, Olga

2015-01-01

The Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations instrument was developed to implement the conceptual framework of the Chronic Care Model in the Spanish national health system. It has been used to assess readiness to tackle chronicity in health care organisations. In this study, we use self-assessments at macro-, meso- and micro-management levels to (a) describe the two-year experience with the Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations tool in Spain and (b) assess the validity and reliability of this instrument. The results from 55 organisational self-assessments were included and described. In addition to that, the internal consistency, reliability and construct validity of Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations were examined using Cronbach's alpha, the Spearman-Brown coefficient and factorial analysis. The obtained scores reflect opportunities for improvement in all dimensions of the instrument. Cronbach's alpha ranged between 0.90 and 0.95 and the Spearman-Brown coefficient ranged between 0.77 and 0.94. All 27 components converged in a second-order factorial solution that explained 53.8% of the total variance, with factorial saturations for the components of between 0.57 and 0.94. Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations is an instrument that allows health care organisations to perform self-assessments regarding their readiness to tackle chronicity and to identify areas for improvement in chronic care.

Distribución espacial de órbitas con diferentes grados de caoticidad en modelos autoconsistentes de satélites galácticos

NASA Astrophysics Data System (ADS)

Muzzio, J. C.; Mosquera, M.

En trabajos anteriores (Carpintero et al., Cel. Mech. Dynam. Astron. 85, 247, 2003), mostramos que las órbitas caóticas son muy importantes en los satélites galácticos. Sin embargo, los únicos modelos autoconsistentes de los que se disponía para ellos eran los de Heggie-Ramamani, cuya función de distribución depende sólo de la energía por lo que no mostraban diferencias entre las distribuciones de sus órbitas regulares y caóticas. Ahora, mediante una aproximación cuadrupolar, hemos logrado construir modelos autoconsistentes de satélites galácticos con distribuciones de velocidades anisotrópicas (lo que indica que sus funciones de distribución no dependen sólo de la energía) y hemos logrado revelar las diferencias entre las estructuras espaciales de las órbitas de distinta caoticidad.

Uso Del Condón en Adolescentes Nahuas, un Modelo Explicativo.

PubMed

Tirado, María de Los Ángeles Meneses; Benavides-Torres, Raquel A; Navarro, Sergio Meneses; de la Colina, Juan Antonio Doncel; Rodríguez, Dora Julia Onofre; Hernández, Francisco Javier Baéz

2018-03-01

En México, la población indígena supera los siete millones de habitantes, en Puebla el grupo más representativo es el Náhuatl. Sin embargo, las condiciones de vida, salud, educación y transporte son precarias para esta población. En los adolescentes, las responsabilidades como el matrimonio, la familia y los compromisos ante la comunidad, favorecen conductas de riesgo sexual que dificultan su desarrollo económico, social y reproductivo. El objetivo fue proponer un modelo explicativo del uso del condón en adolescentes nahuas. Método. Bajo el marco de la teoría social cognitiva, el concepto de valores culturales de Leininger y el proceso de la sustracción teórica, se desarrolló este artículo. Se muestran las relaciones del modelo con las proposiciones y los factores que influyen en el uso del condón para este grupo específico. Finalmente, el modelo explica las variables de interés, los niveles de abstracción y las relaciones entre sí en el contexto náhuatl. El siguiente paso será implementar los indicadores empíricos para conocer el grado de influencia de los factores personales y ambientales hacia el uso del condón en adolescentes nahuas. Resultados que aportarán información para el desarrollo del conocimiento en enfermería y la reducción de riesgo sexual de esta población.

A Maple package for improved global mapping forecast

NASA Astrophysics Data System (ADS)

Carli, H.; Duarte, L. G. S.; da Mota, L. A. C. P.

2014-03-01

We present a Maple implementation of the well known global approach to time series analysis and some further developments designed to improve the computational efficiency of the forecasting capabilities of the approach. This global approach can be summarized as being a reconstruction of the phase space, based on a time ordered series of data obtained from the system. After that, using the reconstructed vectors, a portion of this space is used to produce a mapping, a polynomial fitting, through a minimization procedure, that represents the system and can be employed to forecast further entries for the series. In the present implementation, we introduce a set of commands, tools, in order to perform all these tasks. For example, the command VecTS deals mainly with the reconstruction of the vector in the phase space. The command GfiTS deals with producing the minimization and the fitting. ForecasTS uses all these and produces the prediction of the next entries. For the non-standard algorithms, we here present two commands: IforecasTS and NiforecasTS that, respectively deal with the one-step and the N-step forecasting. Finally, we introduce two further tools to aid the forecasting. The commands GfiTS and AnalysTS, basically, perform an analysis of the behavior of each portion of a series regarding the settings used on the commands just mentioned above. Catalogue identifier: AERW_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AERW_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 3001 No. of bytes in distributed program, including test data, etc.: 95018 Distribution format: tar.gz Programming language: Maple 14. Computer: Any capable of running Maple Operating system: Any capable of running Maple. Tested on Windows ME, Windows XP, Windows 7. RAM: 128 MB Classification: 4.3, 4.9, 5 Nature of problem: Time series analysis and improving forecast capability. Solution method: The method of solution is partially based on a result published in [1]. Restrictions: If the time series that is being analyzed presents a great amount of noise or if the dynamical system behind the time series is of high dimensionality (Dim≫3), then the method may not work well. Unusual features: Our implementation can, in the cases where the dynamics behind the time series is given by a system of low dimensionality, greatly improve the forecast. Running time: This depends strongly on the command that is being used. References: [1] Barbosa, L.M.C.R., Duarte, L.G.S., Linhares, C.A. and da Mota, L.A.C.P., Improving the global fitting method on nonlinear time series analysis, Phys. Rev. E 74, 026702 (2006).

Inherent Error in Asynchronous Digital Flight Controls.

DTIC Science & Technology

1980-02-01

IMAXJ DIIMENSION AP(2,2) PBIP(2v2),CP(lv2) ,FC(2,2) iGC(2,1) , PHIT ’(4,4), I HC(2v2)vEC(2w1)wPHITI(4,4,l01),PSITI(4,4),PHTAU(4,4) ,PSTAU(4,4),I 4 INJ3EX(4...1.0 4 02. CON’T I NUE [𔃺 4 11 :: 2 7NT TI =T14-E:’LTA PHITl(2yJ1,11) =0.0 4 FHIT1(2y2vlJ.) EXP(-10.*TI) [DO 400 11 = lNP DO0 400 JJ = INP 400 PHIT (IlJJ...PHIT1(IIr,J.JYN’T) WRITE(6y860) 860 FORMAT (5X Y’PH IT’) [DO 861 1 -IYiNP 1361 WRITE(6v802) ( PHIT (I9vJ) ,J:=1,NP) DO :1800 KK2 1,J.6 IAU N1

The BCC/B2 morphologies in Al xNiCoFeCr high-entropy alloys

DOE PAGES

Ma, Yue; Jiang, Beibei; Li, Chunling; ...

2017-02-15

Here, the present work primarily investigates the morphological evolution of the body-centered-cubic (BCC)/B2 phases in Al xNiCoFeCr high-entropy alloys (HEAs) with increasing Al content. It is found that the BCC/B2 coherent morphology is closely related to the lattice misfit between these two phases, which is sensitive to Al. There are two types of microscopic BCC/B2 morphologies in this HEA series: one is the weave-like morphology induced by the spinodal decomposition, and the other is the microstructure of a spherical disordered BCC precipitation on the ordered B2 matrix that appears in HEAs with a much higher Al content. The mechanical properties,more » including the compressive yielding strength and microhardness of the Al xNiCoFeCr HEAs, are also discussed in light of the concept of the valence electron concentration (VEC).« less

Standardisation of the ion beam facility at Chandigarh cyclotron for simultaneous PIXE and PESA analysis

NASA Astrophysics Data System (ADS)

Verma, Shivcharan; Mohanty, Biraja P.; Singh, Karn P.; Kumar, Ashok

2018-02-01

The proton beam facility at variable energy cyclotron (VEC) Panjab University, Chandigarh, India is being used for Particle Induced X-ray Emission (PIXE) analysis of different environmental, biological and industrial samples. The PIXE method, however, does not provide any information of low Z elements like carbon, nitrogen, oxygen and fluorine. As a result of the increased need for rapid and multi-elemental analysis of biological and environmental samples, the PIXE facility was upgraded and standardized to facilitate simultaneous measurements using PIXE and Proton Elastic Scattering Analysis (PESA). Both PIXE and PESA techniques were calibrated and standardized individually. Finally, the set up was tested by carrying out simultaneous PIXE and PESA measurements using a 2 mm diameter proton beam of 2.7 MeV on few multilayered thin samples. The results obtained show excellent agreement between PIXE and PESA measurements and confirm adequate sensitivity and precision of the experimental set up.

The fabrication and optical detection of a vertical structure organic thin film transistor

NASA Astrophysics Data System (ADS)

Zhang, H.; Wang, D.; Jia, P.

2014-03-01

Using vacuum evaporation and sputtering process, we prepared a photoelectric transistor with the vertical structure of Cu/copper phthalocyanine (CuPc)/Al/copper phthalocyanine (CuPc)/ITO. The material of CuPc semiconductor has good photosensitive properties. Excitons will be generated after the optical signal irradiation in semiconductor material, and then transformed into photocurrent under the built-in electric field formed by the Schottky contact, as the organic transistor drive current makes the output current enlarged. The results show that the I-V characteristics of transistor are unsaturated. When device was irradiated by full band (white) light, its working current significantly increased. In full band white light, when Vec = 3 V, the ratio of light and no light current was ranged for 2.9-6.4 times. Device in the absence of light current amplification coefficient is 16.5, and white light amplification coefficient is 98.65.

Biaxial seismic behaviour of reinforced concrete columns =

NASA Astrophysics Data System (ADS)

Rodrigues, Hugo Filipe Pinheiro

A analise dos efeitos dos sismos mostra que a investigacao em engenharia sismica deve dar especial atencao a avaliacao da vulnerabilidade das construcoes existentes, frequentemente desprovidas de adequada resistencia sismica tal como acontece em edificios de betao armado (BA) de muitas cidades em paises do sul da Europa, entre os quais Portugal. Sendo os pilares elementos estruturais fundamentais na resistencia sismica dos edificios, deve ser dada especial atencao a sua resposta sob acoes ciclicas. Acresce que o sismo e um tipo de acao cujos efeitos nos edificios exige a consideracao de duas componentes horizontais, o que tem exigencias mais severas nos pilares comparativamente a acao unidirecional. Assim, esta tese centra-se na avaliacao da resposta estrutural de pilares de betao armado sujeitos a acoes ciclicas horizontais biaxiais, em tres linhas principais. Em primeiro lugar desenvolveu-se uma campanha de ensaios para o estudo do comportamento ciclico uniaxial e biaxial de pilares de betao armado com esforco axial constante. Para tal foram construidas quatro series de pilares retangulares de betao armado (24 no total) com diferentes caracteristicas geometricas e quantidades de armadura longitudinal, tendo os pilares sido ensaiados para diferentes historias de carga. Os resultados experimentais obtidos sao analisados e discutidos dando particular atencao a evolucao do dano, a degradacao de rigidez e resistencia com o aumento das exigencias de deformacao, a energia dissipada, ao amortecimento viscoso equivalente; por fim e proposto um indice de dano para pilares solicitados biaxialmente. De seguida foram aplicadas diferentes estrategias de modelacao nao-linear para a representacao do comportamento biaxial dos pilares ensaiados, considerando nao-linearidade distribuida ao longo dos elementos ou concentrada nas extremidades dos mesmos. Os resultados obtidos com as varias estrategias de modelacao demonstraram representar adequadamente a resposta em termos das curvas envolventes forca-deslocamento, mas foram encontradas algumas dificuldades na representacao da degradacao de resistencia e na evolucao da energia dissipada. Por fim, e proposto um modelo global para a representacao do comportamento nao-linear em flexao de elementos de betao armado sujeitos a acoes biaxiais ciclicas. Este modelo tem por base um modelo uniaxial conhecido, combinado com uma funcao de interacao desenvolvida com base no modelo de Bouc- Wen. Esta funcao de interacao foi calibrada com recurso a tecnicas de otimizacao e usando resultados de uma serie de analises numericas com um modelo refinado. E ainda demonstrada a capacidade do modelo simplificado em reproduzir os resultados experimentais de ensaios biaxiais de pilares.

The Model of Optimization of Micro Energy; HOMER: El Modelo de Optimizacin de Micro energa (in Spanish)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

2004-05-01

HOMER, the model of optimization of micro energy, helps to disear systems out of the network and interconnected to the network. You can use HOMER to carry out the analysis to explore an extensive rank of questions of diseo. HOMER, el modelo de optimizacin de micro energa, le ayuda a disear sistemas fuera de la red e interconectados a la red. Usted puede usar HOMER para llevar a cabo el anlisis para explorar un amplio rango de preguntas de diseo.

ERECTA, salicylic acid, abscisic acid, and jasmonic acid modulate quantitative disease resistance of Arabidopsis thaliana to Verticillium longisporum.

PubMed

Häffner, Eva; Karlovsky, Petr; Splivallo, Richard; Traczewska, Anna; Diederichsen, Elke

2014-04-01

Verticillium longisporum is a soil-borne vascular pathogen infecting cruciferous hosts such as oilseed rape. Quantitative disease resistance (QDR) is the major control means, but its molecular basis is poorly understood so far. Quantitative trait locus (QTL) mapping was performed using a new (Bur×Ler) recombinant inbred line (RIL) population of Arabidopsis thaliana. Phytohormone measurements and analyses in defined mutants and near-isogenic lines (NILs) were used to identify genes and signalling pathways that underlie different resistance QTL. QTL for resistance to V. longisporum-induced stunting, systemic colonization by the fungus and for V. longisporum-induced chlorosis were identified. Stunting resistance QTL were contributed by both parents. The strongest stunting resistance QTL was shown to be identical with Erecta. A functional Erecta pathway, which was present in Bur, conferred partial resistance to V. longisporum-induced stunting. Bur showed severe stunting susceptibility in winter. Three stunting resistance QTL of Ler origin, two co-localising with wall-associated kinase-like (Wakl)-genes, were detected in winter. Furthermore, Bur showed a much stronger induction of salicylic acid (SA) by V. longisporum than Ler. Systemic colonization was controlled independently of stunting. The vec1 QTL on chromosome 2 had the strongest effect on systemic colonization. The same chromosomal region controlled the level of abscisic acid (ABA) and jasmonic acid (JA) in response to V. longisporum: The level of ABA was higher in colonization-susceptible Ler than in colonization-resistant Bur after V. longisporum infection. JA was down-regulated in Bur after infection, but not in Ler. These differences were also demonstrated in NILs, varying only in the region containing vec1. All phytohormone responses were shown to be independent of Erecta. Signalling systems with a hitherto unknown role in the QDR of A. thaliana against V. longisporum were identified: Erecta mediated resistance against V. longisporum-induced stunting. Independent of Erecta, stunting was caused in a light-dependent manner with possible participation of SA and Wakl genes. ABA and JA showed a genotype-specific response that corresponded with systemic colonization by the fungus. Understanding the biological basis of phenotypic variation in A. thaliana with respect to V. longisporum resistance will provide new approaches for implementing durable resistance in cruciferous crops.

Studies on magnetocaloric and magnetic coupling effects =

NASA Astrophysics Data System (ADS)

Amaral, Joao Cunha de Sequeira

O presente trabalho apresenta novas metodologias desenvolvidas para a analise das propriedades magneticas e magnetocaloricas de materiais, sustentadas em consideracoes teoricas a partir de modelos, nomeadamente a teoria de transicoes de fase de Landau, o modelo de campo medio molecular e a teoria de fenomeno critico. Sao propostos novos metodos de escala, permitindo a interpretacao de dados de magnetizacao de materiais numa perspectiva de campo medio molecular ou teoria de fenomeno critico. E apresentado um metodo de estimar a magnetizacao espontanea de um material ferromagnetico a partir de relacoes entropia/magnetizacao estabelecidas pelo modelo de campo medio molecular. A termodinamica das transicoes de fase magneticas de primeira ordem e estudada usando a teoria de Landau e de campo medio molecular (modelo de Bean-Rodbell), avaliando os efeitos de fenomenos fora de equilibrio e de condicoes de mistura de fase em estimativas do efeito magnetocalorico a partir de medidas magneticas. Efeitos de desordem, interpretados como uma distribuicao na interaccao magnetica entre ioes, estabelecem os efeitos de distribuicoes quimicas/estruturais nas propriedades magneticas e magnetocaloricas de materiais com transicoes de fase de segunda e de primeira ordem. O uso das metodologias apresentadas na interpretacao das propriedades magneticas de variados materiais ferromagneticos permitiu obter: 1) uma analise quantitativa da variacao de spin por iao Gadolinio devido a transicao estrutural do composto Gd5Si2Ge2, 2) a descricao da configuracao de cluster magnetico de ioes Mn na fase ferromagnetica em manganites da familia La-Sr e La-Ca, 3) a determinacao dos expoentes criticos β e δ do Niquel por metodos de escala, 4) a descricao do efeito da pressao nas propriedades magneticas e magnetocaloricas do composto LaFe11.5Si1.5 atraves do modelo de Bean-Rodbell, 5) uma estimativa da desordem em manganites ferromagneticas com transicoes de segunda e primeira ordem, 6) uma descricao de campo medio das propriedades magneticas da liga Fe23Cu77, 7) o estudo de efeitos de separacao de fase na familia de compostos La0.70-xErxSr0.30MnO3 e 8) a determinacao realista da variacao de entropia magnetica na familia de compostos de efeito magnetocalorico colossal Mn1-x-yFexCryAs.

Novas determinações dos parâmetros atmosféricos das estrelas anãs brancas DA

NASA Astrophysics Data System (ADS)

Giovannini, O.; Costa, A. F. M.; Kepler, S. O.

2003-08-01

Nós temos selecionado uma amostra de estrelas anãs brancas DA (atmosfera de hidrogênio) a partir dos índices de Strömgren cujos valores estão próximos a região de instabilidade das estrelas anãs brancas DA variáveis, as chamadas estrelas DAV ou ZZ Ceti. O objetivo é determinar os parâmetros fundamentais (temperatura efetiva, Teff, aceleração da gravidade, log g, e massa) destas estrelas para verificar quais os parâmetros estelares estão envolvidos com o mecanismo de pulsação das estrelas DAV. Nós obtemos, até agora, mais de 120 espectros óticos de estrelas DA. Entre as estrelas selecionadas há 20 estrelas variáveis (DAV). Assim, podemos verificar se existem ou não estrelas não variáveis dentro da faixa de instabilidade das estrelas ZZ Ceti. Neste trabalho nós apresentamos a determinação dos parâmetros atmosféricos (temperatura efetiva, Teff, e aceleração da gravidade, log g) das estrelas anãs brancas DA usando os novos modelos de atmosfera ML2/a = 0.6. Estes modelos têm sido utilizados recentemente por fornecerem uma excelente consistência interna na determinação das temperaturas nas regiões do ultra-violeta e ótico. Os parâmetros atmosféricos são determinados espectroscopicamente através da comparação do fluxo de energia das linhas de Balmer (Hb à H9) entre os espectros observados e sintéticos (gerados pelos modelos de atmosfera). As temperaturas obtidas com os novos modelos são, em geral, menores (~ 1000 K menos) que as temperaturas determinadas anteriormente, com modelos ML1. Os valores de log g não mudaram significativamente (menos de 10%). A faixa de instabilidade das DAVs está entre 11000 e 13000 K, consistente com dados de outros autores.

Desenvolvimento de modelo clínico para predição da possibilidade de identificação da artéria de Adamkiewicz por angiotomografia

PubMed Central

Amato, Alexandre Campos Moraes; Parga, José Rodrigues; Stolf, Noedir Antônio Groppo

2018-01-01

Resumo Contexto Diferenças morfológicas da artéria de Adamkiewicz (AKA) entre a população portadora e não portadora de doença aórtica têm importância clínica, influenciando as complicações neuroisquêmicas da medula espinhal em procedimentos operatórios. Ainda não é conhecida a correlação entre parâmetros clínicos e a previsibilidade da identificação dessa artéria pela angiotomografia. Objetivo Desenvolver um modelo matemático que, através de parâmetros clínicos correlacionados com aterosclerose, possa prever a probabilidade de identificação da AKA em pacientes submetidos a angiotomografias. Método Estudo observacional transversal utilizando banco de imagens e dados de pacientes. Foi feita análise estatística multivariada e criado modelo matemático logit de predição para identificação da AKA. Variáveis significativas foram utilizadas na montagem da fórmula para cálculo da probabilidade de identificação. O modelo foi calibrado, e a discriminação foi avaliada pela curva receiver operating characteristic (ROC). A seleção das variáveis explanatórias foi guiada pela maior área na curva ROC (p = 0,041) e pela significância combinada das variáveis. Resultados Foram avaliados 110 casos (54,5% do sexo masculino, com idade média de 60,97 anos e etnia com coeficiente B -2,471, M -1,297, N -0,971), com AKA identificada em 60,9%. Índice de massa corporal: 27,06 ± 0,98 (coef. -0,101); fumantes: 55,5% (coef. -1,614/-1,439); diabéticos: 13,6%; hipertensos: 65,5% (coef. -1,469); dislipidêmicos: 58,2%; aneurisma aórtico: 38,2%; dissecção aórtica: 12,7%; e trombo mural: 24,5%. Constante de 6,262. Fórmula para cálculo da probabilidade de detecção: (e−(Coef. Etnia+(Coef. IMC×IMC)+Coef.fumante+Coef.HAS+Coef.dislip+Constante)+1)−1 . O modelo de predição foi criado e disponibilizado no link https://vascular.pro/aka-model . Conclusão Com as covariáveis etnia, índice de massa corporal, tabagismo, hipertensão arterial e dislipidemia, foi possível criar um modelo matemático de predição de identificação da AKA com significância combinada de nove coeficientes (p = 0,042). PMID:29930677

Incorporando a variabilidade no processo de identificação do modelo de máximo global no Grade of Membership (GoM): considerações metodológicas

PubMed Central

Guedes, Gilvan Ramalho; Siviero, Pamila Cristina Lima; Caetano, André Junqueira; Machado, Carla Jorge; Brondízio, Eduardo

2012-01-01

A disponibilidade de bases de dados cada vez mais complexas e multidimensionais é um dos principais motivadores para o aumento do número de estudos que utilizam análises multivariadas baseadas em lógica de conjuntos nebulosos. Apesar da disseminação do método Grade of Membership nos trabalhos empíricos brasileiros da área de ciências sociais e saúde, questões relativas à identificabilidade e estabilidade dos parâmetros finais estimados pelo programa GoM 3.4 não foram suficientemente aprofundadas. Dada a relevância de se obterem parâmetros únicos e estáveis, Guedes et al. (2010) propuseram um procedimento empírico para localizar um modelo de máximo global (MG) com parâmetros estáveis. Entretanto, seu localizador de MG não incorpora qualquer medida de variabilidade. Neste artigo, tal limitação é contornada por meio da utilização de uma estatística de ponderação – Máximo Global Ponderado (MGP) – semelhante ao coeficiente de variação. Esse indicador busca não penalizar de forma desproporcional situações nas quais os desvios médios, apesar de diferentes de zero, são muito pequenos. Apresentam-se evidências de que o localizador MGP reduz a distância do modelo identificado à real estrutura latente dos dados em análise, quando comparados ao modelo identificado pelo localizador não ponderado, MG. PMID:23293402

ARCGRAPH SYSTEM - AMES RESEARCH GRAPHICS SYSTEM

NASA Technical Reports Server (NTRS)

Hibbard, E. A.

1994-01-01

Ames Research Graphics System, ARCGRAPH, is a collection of libraries and utilities which assist researchers in generating, manipulating, and visualizing graphical data. In addition, ARCGRAPH defines a metafile format that contains device independent graphical data. This file format is used with various computer graphics manipulation and animation packages at Ames, including SURF (COSMIC Program ARC-12381) and GAS (COSMIC Program ARC-12379). In its full configuration, the ARCGRAPH system consists of a two stage pipeline which may be used to output graphical primitives. Stage one is associated with the graphical primitives (i.e. moves, draws, color, etc.) along with the creation and manipulation of the metafiles. Five distinct data filters make up stage one. They are: 1) PLO which handles all 2D vector primitives, 2) POL which handles all 3D polygonal primitives, 3) RAS which handles all 2D raster primitives, 4) VEC which handles all 3D raster primitives, and 5) PO2 which handles all 2D polygonal primitives. Stage two is associated with the process of displaying graphical primitives on a device. To generate the various graphical primitives, create and reprocess ARCGRAPH metafiles, and access the device drivers in the VDI (Video Device Interface) library, users link their applications to ARCGRAPH's GRAFIX library routines. Both FORTRAN and C language versions of the GRAFIX and VDI libraries exist for enhanced portability within these respective programming environments. The ARCGRAPH libraries were developed on a VAX running VMS. Minor documented modification of various routines, however, allows the system to run on the following computers: Cray X-MP running COS (no C version); Cray 2 running UNICOS; DEC VAX running BSD 4.3 UNIX, or Ultrix; SGI IRIS Turbo running GL2-W3.5 and GL2-W3.6; Convex C1 running UNIX; Amhdahl 5840 running UTS; Alliant FX8 running UNIX; Sun 3/160 running UNIX (no native device driver); Stellar GS1000 running Stellex (no native device driver); and an SGI IRIS 4D running IRIX (no native device driver). Currently with version 7.0 of ARCGRAPH, the VDI library supports the following output devices: A VT100 terminal with a RETRO-GRAPHICS board installed, a VT240 using the Tektronix 4010 emulation capability, an SGI IRIS turbo using the native GL2 library, a Tektronix 4010, a Tektronix 4105, and the Tektronix 4014. ARCGRAPH version 7.0 was developed in 1988.

Uso de modelos mecânicos em curso informal de astronomia para deficientes visuais. Resgate de uma experiência

NASA Astrophysics Data System (ADS)

Tavares, E. T., Jr.; Klafke, J. C.

2003-08-01

O presente trabalho propõe-se a resgatar uma experiência que teve lugar no Planetário de São Paulo nos anos 60. Em 1962, o Sr. Acácio, então com 37 anos, deficiente visual desde os 27, passou a assistir às aulas ministradas pelo Prof. Aristóteles Orsini aos integrantes do corpo de servidores do Planetário. O Sr. Acácio era o único deficiente da turma e, embora possuísse conhecimentos básicos e relativamente avançados de matemática, enfrentava dificuldades na compreensão e acompanhamento da exposição, como também em estudos posteriores. Com o intuito de auxiliá-lo na superação desses problemas, o Prof. Orsini solicitou a construção de modelos mecânicos que, através do sentido do tato, permitissem o acompanhamento das aulas e a transposição do modelo para o "constructo" mental. Essa prática mostrou-se tão eficaz que facilitou sobejamente o aprendizado da matéria pelo sujeito. O Sr. Acácio passou a integrar o corpo de professores do Planetário/Escola Municipal de Astrofísica, tendo ficado responsável pelo curso de "Introdução à Astronomia" por vários anos. Além disso, a experiência foi tão bem sucedida que alguns dos modelos tiveram seus elementos constitutivos pintados diferencialmente para serem utilizados em cursos regulares do Planetário, tornando-se parte integrante do conjunto de recursos didáticos da instituição. É pensando nessa eficácia, tanto em seu objetivo original permitir o aprendizado de um deficiente visual quanto no subsidiário recurso didático sistemático da instituição que decidimos resgatar essa experiência. Estribados nela, acreditamos ser extremamente produtivo, em termos educacionais, o aperfeiçoamento dos modelos originais, agora resgatados e restaurados, e a criação de outros que pudessem ser utilizados no ensino dessa ciência a deficientes visuais.

Evolución de estrellas enanas blancas de Helio de masa baja e intermedia

NASA Astrophysics Data System (ADS)

Althaus, L. G.; Benvenuto, O. G.

Numerosas observaciones realizadas particularmente en los últimos dos años parecen confirmar que las enanas blancas (EB) de helio de masa baja e intermedia son el resultado de la evolución de sistemas binarios cercanos. Con el objeto de realizar una adecuada interpretación de estos objetos son necesarios modelos de EBs de helio lo más detallado posibles. En este estudio presentamos cálculos detallados de la evolución de EBs de helio con masas entre M=0.1Msolar y M=0.5Msolar a intervalos de 0.05Msolar . Para ello, hemos tenido en cuenta los efectos de temperatura finita mediante un código de evolución estelar lo más actualizado posible. En particular, el transporte de energía es descripto en el marco del nuevo modelo para la convección turbulenta desarrollado por Canuto - Mazzitelli. Además hemos considerado la nueva ecuación de estado para plasmas de helio de Saumon et al. y nuevas opacidades radiativas OPAL. Las pérdidas por neutrinos fueron asimismo tenidas en cuenta. Excepto para las EBs más masivas, nuestros modelos iniciales están ubicados en las cercanías de la correspondiente línea de Hayashi para configuraciones de helio. Nuestros resultados muestran que existe una región prohibida en el diagrama observacional HR donde ninguna EB de helio puede encontrarse. Dicha región es para log{(L/Lsolar )}>= -0.25 and log{Teff} >= 4.45. Hemos encontrado también que los tracks evolutivos en el diagrama HR en el dominio de alta luminosidad (pre - EB) son fuertemente afectados por la eficiencia convectiva y que las pérdidas por neutrinos son importantes en los modelos más masivos. Finalmente hemos analizado la estructura de la zona convectiva externa encontrando que la teoría de Canuto - Mazzitelli conduce a un perfil convectivo muy diferente del dado por cualquier versión de la popular teoría de la mixing length. Si bién este comportamiento es decisivo en el contexto de las inestabilides pulsacionales, los radios y gravedades superficiales de los modelos no son afectados al incluir la nueva teoría de convección.

In search of superluminal quantum communications: recent experiments and possible improvements

NASA Astrophysics Data System (ADS)

Cocciaro, B.; Faetti, S.; Fronzoni, L.

2013-06-01

As shown in the famous EPR paper (Einstein, Podolsky e Rosen, 1935), Quantum Mechanics is non-local. The Bell theorem and the experiments by Aspect and many others, ruled out the possibility of explaining quantum correlations between entangled particles using local hidden variables models (except for implausible combinations of loopholes). Some authors (Bell, Eberhard, Bohm and Hiley) suggested that quantum correlations could be due to superluminal communications (tachyons) that propagate isotropically with velocity vt > c in a preferred reference frame. For finite values of vt, Quantum Mechanics and superluminal models lead to different predictions. Some years ago a Geneva group and our group did experiments on entangled photons to evidence possible discrepancies between experimental results and quantum predictions. Since no discrepancy was found, these experiments established only lower bounds for the possible tachyon velocities vt. Here we propose an improved experiment that should lead us to explore a much larger range of possible tachyon velocities Vt for any possible direction of velocity vec V of the tachyons preferred frame.

Difusión de Arnold en un modelo simple

NASA Astrophysics Data System (ADS)

Cincotta, P. M.; Nuñez, J. A.; Miloni, O.

Investigadores como Merritt, Valluri, Pfenniger o Contopoulos (por citar los más relevantes) consideran seriamente la hipótesis que la difusión de Arnold juega un rol importante en la evolución dinámica de los sistemas estelares y planetarios. Sin embargo no existe ninguna evidencia. El mayor problema para investigar fenómenos como éste es que uno debe estudiar numéricamente sistemas multidimensionales (más de dos grados de libertad) y visualizar de alguna manera el espacio de fases (más de cuatro dimensiones). Más complicado aún es el caso de difusión de Arnold, donde deben considerarse tiempos de movimiento extremadamente largos y tratar con parámetros exponencialmente pequeños. El propósito de este trabajo es estudiar, en un modelo simple 3D, la existencia o no de difusión de Arnold mediante experimentos numéricos y estimaciones analíticas. Siguiendo los trabajos de Cincotta (2000) y Cincotta, Nuñez y Simo (2000), aquí se pretende ``visualizar" la difusión y, a la vez, determinar la escala de tiempo en la que ésta se podría manifestar. Este trabajo es el escalón inicial para luego abordar este problema en modelos.

Ajuste de parámetros libres en teorías de campos camaleones a partir de espectros de nubes moleculares galácticas y experimentos terrestres

NASA Astrophysics Data System (ADS)

Teppa Pannia, F. A.; Landau, S. J.

Resultados recientes, basados en el análisis de espectros moleculares de nubes galácticas a través del método del amoníaco, han arrojado nuevos límites sobre la variación del parámetro adimensional μ=m_e /m_p. Los resultados indican Δ μ/μ = (μ_{obs}-μ_{lab})/μ_{lab}= (2.2± 0.4_{est} ±0.3_{sist}) times 10 ^{-8}, en acuerdo con una variación no nula de dicha cantidad (Levshakov et al. 2010). En este trabajo, motivado por los datos astronómicos, estudiamos la solución lineal del modelo teórico fenomenológico de campo escalar camaleón, presentado por Mota y Shaw (2007), que predice variaciones en μ. Con el fin de cotejar estas predicciones con los resultados observacionales, utilizamos datos de experimentos terrestres que testean violaciones al Principio de Equivalencia para analizar el valor de los parámetros libres presentes en el modelo. El trabajo realizado muestra que la solución estudiada no se puede ajustar a los datos experimentales, sugiriendo que el modelo lineal debe ser descartado para explicar las observaciones astronómicas. FULL TEXT IN SPANISH

Estudio de la formación de galaxias espirales en un modelo de agregación jerárquica

NASA Astrophysics Data System (ADS)

Tissera, P.; Saiz, A.; Dominguez-Tenreiro, R.

El estudio de formación de galaxias espirales ha llevado al desarrollo de numerosos modelos teóricos (e.g. White & Rees 1978). En la actualidad, el modelo más aceptado predice la formación de una galaxia espiral a partir del colapso disipativo del gas en el pozo de potencial de un halo oscuro, conservando su momento angular específco (Fall & Efstathiou 1980). En los últimos años, ha sido posible realizar simulaciones numéricas hidrodinámicas, las cuales describen la evolución conjunta de la materia oscura y los bariones. Estos experimentos han señalado la dificultad de formar estructuras discoidales con propiedades consistentes con las observaciones, en modelos de agregación jerárquica. El problema principal se origina en la pérdida catastrófica de momento angular de la componente disipativa, durante el proceso de ensamblaje de los objetos, a través de la fusión de subestructura (Navarro & Steinmetz 1997). Estos experimentos no incluían procesos de formación estelar. En este trabajo, se expondrán resultados de simulaciones hidrodinámicas cosmológicas, incluyendo formación estelar (Tissera et al 1997), donde ha sido posible reproducir objetos discoidales con contrapartida observacional. El elemento fundamental ha sido la formación de bulbos estelares, los cuales han evitado la pérdida catastrófica de momento angular de los bariones. Se encontró que los discos exponenciales puramente gaseosos son altamente inestables y suceptibles de generar barras, responsables de la pérdida de momento angular y la caída violenta del gas hacia la región central. Estas inestabilidades son fácilmente inducidas durante interacciones y fusiones con objetos vecinos (Barnes & Hernquist 1996). Un bulbo estelar (o un objeto masivo y compacto) estabiliza el disco ante perturbaciones externas, asegurándole un potencial simétrico (Sellwood & Moore 1998, Van der Bosch 1998). En este caso, el gas en el disco no pierde completamente su momento angular intrínseco durante las fusiones, sino que, las sobrevive aportando una contribución distinta de cero, a partir de la cual el disco se regenera acretando en una segunda etapa, gas del halo de acuerdo al modelo tradicional de Fall & Efstathiou.

Condiciones Físicas en Nebulosas Gaseosas

NASA Astrophysics Data System (ADS)

Luridiana, V.

1999-03-01

El presente trabajo se ha enfocado a determinar y entender las condiciones físicas en una variedad de objetos nebulares, prestando particular atención al problema de la determinación de las abundancias químicas. Para este fin, hemos utilizado métodos analíticos en algunos casos, y modelos numéricos de fotoionización en otros. El objetivo general del trabajo es proveer de una visión amplia de las herramientas teórico-observacionales que se utilizan para la determinación de la estructura de temperatura y densidad de las regiones fotoionizadas, poniendo en evidencia posibles fuentes de errores sistemáticos y sus consecuencias para la determinación de las abundancias químicas, y proponiendo métodos para corregirlos. Los resultados principales de este trabajo est´n listados a continuación: a) Se discute el problema de la discrepancia entre T(C III) y T(O III) en las nebulosas planetarias, y se muestra como tal discrepancia implica probablemente la presencia de fluctuaciones de temperatura. Debido a que la temperatura de O++ es muy afectada por fluctuaciones de temperatura, se recomienda usar la temperatura de C++ para determinar la abundancia de carbono. b) Presentamos dos nuevos métodos para determinar la temperatura electrónica en nebulosas planetarias, basados en la medición de las intensidades de las líneas de He I. Las temperaturas que se obtienen a partir de estos métodos son menores que aquellas que se obtienen a partir de las líneas de [O III], implicando la presencia de fluctuaciones espaciales de temperatura. Despreciando las fluctuaciones de temperatura, se obtienen valores sesgados de las abundancias químicas. Determinamos las abundancias en las nebulosas planetarias de tipo I de algunos de los elementos más importantes, tomando en cuenta las fluctuaciones de temperatura. c) Presentamos modelos numéricos de las dos regiones H II extragalácticas gigantes NGC 2363 y NGC 5461. Con el modelaje numérico, pretendemos acotar las carácteristicas principales de las nubes ionizadas (distribución espacial del gas, estructura de ionización y de temperatura) y de los cúmulos ionizantes (función inicial de masa, historia de formación estelar, edad). En ambos casos, mostramos que con modelos numéricos calculados para el valor de metalicidad que se determina a partir de la temperatura de [O III], no es posible reproducir el espectro de emisión observado, y que para reproducir las restricciones más robustas es necesario subir la metalicidad de los modelos por un factor de 2. Esto constituye una fuerte indicación en favor de la presencia de fluctuaciones de temperatura. d) Para poder comparar los modelos numéricos con los datos observacionales. mostramos la importancia de corregir las predicciones de los modelos por el sesgo introducido por el tamaío finito de la rendija.

Is the Dark Side of the Moon Ever Illuminated by the Sun? (Breton Title: O Lado Escuro da Lua Nunca Apanha Sol?) El Lado Oscuro de la Luna Nunca Toma Sol?

NASA Astrophysics Data System (ADS)

Giovannini, Odilon; Pellenz, Daiana; Catelli, Francisco

2014-07-01

This work presents the elaboration of an answer to the question "Is the dark side of the moon ever illuminated by the sun?", in which issues related to the students' conceptions, how they arise, and the core elements that constitute a "good answer" are considered. These issues are initially elaborated from a literature review of the research in the field; then, and also based on this review, a didactic model that involves the relative motions of the Earth - Moon - Sun system is proposed. A description of the application of this model in a learning environment within middle school students is described. This work confirms the students' initial concepts described in the literature; on the other hand, the questions asked by students during the activity provide evidence that meaningful learning, at least to some degree, has occurred. Este trabalho apresenta a elaboração de uma resposta à pergunta "O lado escuro da Lua nunca apanha sol?" na qual são consideradas questões relacionadas às concepções iniciais dos alunos, de onde elas surgem e os elementos centrais que constituem uma "boa resposta". Essas questões são tratadas, inicialmente, a partir de uma revisão da literatura sobre pesquisas na área e, em seguida, também com base nessa revisão, um objeto modelo didático que envolve os movimentos relativos do sistema Terra - Lua - Sol é proposto. Uma descrição detalhada da aplicação deste modelo em um ambiente de aprendizagem com alunos do ensino fundamental é relatada. As concepções iniciais apresentadas na literatura se confirmam e os questionamentos feitos pelos estudantes por ocasião da aplicação do modelo fornecem indícios de que uma aprendizagem significativa, pelo menos em algum grau, ocorreu. El artículo se presenta el desarrollo de una respuesta a la pregunta "¿El lado oscuro de la luna nunca toma sol?", en la que se consideran algunas cuestiones vinculadas que se refieren a las concepciones iniciales de los estudiantes, dónde surgen y los elementos básicos que componen una "respuesta correcta". Estas cuestiones se tratan inicialmente a partir de una revisión bibliográfica de la investigación en el área; seguidamente, y también sobre la base de ésta revisión, se propone un modelo didáctico que ejemplifica los movimientos relativos del sistema Tierra - Luna - Sol. Se describe a continuación una aplicación de este modelo en un entorno de aprendizaje con alumnos del ciclo primario. Los conceptos iniciales presentados en la literatura se confirman y las cuestiones planteadas por los estudiantes durante la implementación del modelo proporcionan evidencia de que se ha producido un aprendizaje significativo, al menos en cierta medida.

Life-cycle optimization model for distributed generation in buildings

NASA Astrophysics Data System (ADS)

Safaei, Amir

O setor da construcao e responsavel por uma grande parte do consumo de energia e emissoes na Uniao Europeia. A Geracao Distribuida (GD) de energia, nomeadamente atraves de sistemas de cogeracao e tecnologias solares, representa um papel importante no futuro energetico deste setor. A otimizacao do funcionamento dos sistemas de cogeracao e uma tarefa complexa, devido as diversas variaveis em jogo, designadamente: os diferentes tipos de necessidades energeticas (eletricidade, aquecimento e arrefecimento), os precos dinamicos dos combustiveis (gas natural) e da eletricidade, e os custos fixos e variaveis dos diferentes sistemas de GD. Tal torna-se mais complexo considerando a natureza flutuante das tecnologias solares termicas e fotovoltaicas. Ao mesmo tempo, a liberalizacao do mercado da eletricidade permite exportar para a rede, a electricidade gerada localmente. Adicionalmente, a operacao estrategica de um sistema de GD deve atender aos quadros politicos nacionais, se tiver como objetivo beneficiar de tais regimes. Alem disso, considerando os elevados impactes ambientais do setor da construcao, qualquer avaliacao energetica de edificios rigorosa deve tambem integrar aspetos ambientais, utilizando uma abordagem de Ciclo de Vida (CV). Uma avaliacao de Ciclo de Vida (ACV) completa de um sistema de GD deve incluir as fases relativas a operacao e construcao do sistema, bem como os impactes associados a producao dos combustiveis. Foram analisadas as emissoes da producao de GN, as quais variam de acordo com a origem, tipo (convencional ou nao-convencional), e estado (na forma de GN Liquefeito (GNL) ou gas). Do mesmo modo, o impacte dos sistemas solares e afetado pela meteorologia e radiacao solar, de acordo com a sua localizacao geografica. Sendo assim, uma avaliacao adequada dos sistemas de GD exige um modelo de ACV adequado a localizacao geografica (Portugal), integrando tambem a producao de combustivel (GN), tendo em conta as suas diferentes fontes de abastecimento. O principal objetivo desta tese de doutoramento foi desenvolver um modelo para otimizar o desenho e operacao de sistemas de GD para o setor da construcao de edificios comerciais em Portugal, considerando os respetivos Impactes de Ciclo de Vida (IAVC) e Custos de Ciclo de Vida (CCV), de modo a satisfazer as necessidades energeticas do edificio. Tres tipos de tecnologias de cogeracao (Micro-Turbinas, Motores de combustao interna, e Celulas combustiveis de Oxido solido), e dois tipos de tecnologias de energia solar, solar termica e fotovoltaica, constituem os sistemas de GD que sao acoplados aos sistemas convencionais. Foi desenvolvido um modelo de CV, tendo em conta todos os impactes relacionados com a construcao e operacao dos sistemas de energia, bem como os processos a montante relacionados com a producao do GN. Em particular, o mix de GN consumido em Portugal em 2011 foi identificado (60% da Nigeria, 40% da Argelia) e os impactes relativos a cada uma das vias de abastecimento foram avaliados separadamente para quatro categorias de impacte ambiental: Consumo de Energia Primaria (CEP), Gases com Efeito de Estufa (GEE), acidificacao, e eutrofizacao. Devido a importancia das emissoes de GEE na formulacao de politicas, foi tambem realizada uma analise de incerteza as emissoes de GEE do GN fornecido a Portugal. Foi desenvolvido um modelo matematico, em linguagem de Programacao General Algebraic Modeling System (GAMS), que utiliza os resultados da ACV dos sistemas de energia e as suas implicacoes economicas para minimizar o CCV e IACV ao longo de um horizonte de planeamento definido pelo decisor. Foram derivadas fronteiras otimas de Pareto, representando as relacoes entre o tipo de IACV (CEP, GEE, acidificacao, eutrofizacao) e CCV decorrentes da satisfacao das necessidades energeticas do edificio. Para aumentar a robustez do modelo, dada a incerteza dos precos dos combustiveis (GN e eletricidade), foi desenvolvido um modelo de custos robusto para os sistemas de GD, que e menos afetado por perturbacoes relativas aos custos de combustivel. A aplicacao do modelo proposto foi testada num caso de estudo real, um edificio comercial localizado na cidade de Coimbra, em Portugal.

DESAFÍOS ÉTICOS DE LA INVESTIGACIÓN CON ANIMALES, MANIPULACIÓN GENÉTICA

PubMed Central

Yunta, Eduardo Rodríguez

2012-01-01

En la investigación con animales existen cuestionamientos éticos tanto en el uso como modelos de enfermedades humanas y requisito previo para ensayos en humanos como en la introducción de modificaciones genéticas. Algunos de estos cuestionamientos son: no representar exactamente la condición humana como modelos, realizar pruebas de toxicidad con grave daño para los animales, alterar su naturaleza mediante modificaciones genéticas, riesgos de la introducción de organismos genéticamente modificados. El uso de animales en investigación para beneficio humano, impone al ser humano la responsabilidad moral de respetarlo, no haciéndoles sufrir innecesariamente, al estar trabajando con seres vivientes y sentientes. PMID:23338641

Estructura espacial de las órbitas caóticas en un modelo autoconsistente de galaxia elíptica

NASA Astrophysics Data System (ADS)

Muzzio, J. C.

Hemos logrado construir modelos autoconsistentes de sistemas estelares utilizando una aproximación cuadrupolar para el potencial. Esto nos permite determinar órbitas y exponentes de Lyapunov de objetos que tienen posiciones y velocidades equivalentes a las que se obtienen de la funcón de distribución del sistema. La distribución espacial de las órbitas caóticas exhibe considerable estructura y, lo que es más importante aún, los valores de los exponentes de Lyapunov calculados sobre intervalos finitos de tiempo, muestran una fuerte correlación con el comportamiento de la órbita en esos mismos intervalos, por lo que permiten reconocer distintos subsistemas con diferentes distribuciones espaciales.

Perda de massa em ventos empoeirados de estrelas supergigantes

NASA Astrophysics Data System (ADS)

Vidotto, A. A.; Jatenco-Pereira, V.

2003-08-01

Em praticamente todas as regiões do diagrama HR, as estrelas apresentam evidências observacionais de perda de massa. Na literatura, pode-se encontrar trabalhos que tratam tanto do diagnóstico da perda de massa como da construção de modelos que visam explicá-la. O amortecimento de ondas Alfvén tem sido utilizado como mecanismo de aceleração de ventos homogêneos. Entretanto, sabe-se que os envelopes de estrelas frias contêm grãos sólidos e moléculas. Com o intuito de estudar a interação entre as ondas Alfvén e a poeira e a sua conseqüência na aceleração do vento estelar, Falceta-Gonçalves & Jatenco-Pereira (2002) desenvolveram um modelo de perda de massa para estrelas supergigantes. Neste trabalho, apresentamos um estudo do modelo acima proposto para avaliar a dependência da taxa de perda de massa com alguns parâmetros iniciais como, por exemplo, a densidade r0, o campo magnético B0, o comprimento de amortecimento da onda L0, seu fluxo f0, entre outros. Sendo assim, aumentando f0 de 10% a partir de valores de referência, vimos que aumenta consideravelmente, enquanto que um aumento de mesmo valor em r0, B0 e L0 acarreta uma diminuição em .

Toward Advanced Nursing Practice along with People-Centered Care Partnership Model for Sustainable Universal Health Coverage and Universal Access to Health.

PubMed

Kamei, Tomoko; Takahashi, Keiko; Omori, Junko; Arimori, Naoko; Hishinuma, Michiko; Asahara, Kiyomi; Shimpuku, Yoko; Ohashi, Kumiko; Tashiro, Junko

2017-01-30

this study developed a people-centered care (PCC) partnership model for the aging society to address the challenges of social changes affecting people's health and the new role of advanced practice nurses to sustain universal health coverage. a people-centered care partnership model was developed on the basis of qualitative meta-synthesis of the literature and assessment of 14 related projects. The ongoing projects resulted in individual and social transformation by improving community health literacy and behaviors using people-centered care and enhancing partnership between healthcare providers and community members through advanced practice nurses. people-centered care starts when community members and healthcare providers foreground health and social issues among community members and families. This model tackles these issues, creating new values concerning health and forming a social system that improves quality of life and social support to sustain universal health care through the process of building partnership with communities. a PCC partnership model addresses the challenges of social changes affecting general health and the new role of advanced practice nurses in sustaining UHC. o estudo desenvolveu um modelo de parceria de cuidados centrados nas pessoas (CCP) para uma sociedade que está envelhecendo, com o fim de enfrentar os desafios das mudanças sociais que afetam a saúde das pessoas e o novo papel da prática avançada de enfermagem para sustentar a cobertura universal de saúde. um modelo de parceria de cuidados centrados nas pessoas foi desenvolvido com base na meta-síntese qualitativa da literatura e a avaliação de 14 projetos relacionados. Os projetos em curso resultaram na transformação individual e social, melhorando a alfabetização de saúde da comunidade e comportamentos que usam o cuidado centrado nas pessoas e aumentando a parceria entre os profissionais de saúde e membros da comunidade por meio da prática avançada de enfermagem. o cuidado centrado nas pessoas começa quando os membros da comunidade e os profissionais de saúde colocam em primeiro plano as questões sociais entre os membros da comunidade e das famílias. Esse modelo aborda essas questões, a criação de novos valores relativos à saúde e forma um sistema social que melhora a qualidade de vida e dá apoio social para sustentar o sistema de saúde universal por meio da construção de parcerias com as comunidades. um modelo de parceria CCP aborda os desafios das mudanças sociais que afetam a saúde geral e o novo papel das enfermeiras de prática avançada em sustentar a UHC. este estudio desarrolló un modelo de alianza para el cuidado centrado en las personas (CCP) para una sociedad envejecida, que haga frente a los retos de los cambios sociales que afectan a la salud de las personas y el nuevo papel de las enfermeras de práctica avanzada para apoyar la cobertura universal de salud. un modelo de alianza para el cuidado centrado en las personas fue desarrollado sobre la base de la meta-síntesis cualitativa de la literatura y la evaluación de 14 proyectos relacionados. Los proyectos en curso dieron lugar a la transformación individual y social mejorando la "alfabetización sanitaria" de la comunidad y los comportamientos, utilizando los cuidados centrados en las personas y aumentando la colaboración entre los profesionales sanitarios y miembros de la comunidad a través de las enfermeras de práctica avanzada. el cuidado centrado en las personas comienza cuando los miembros de la comunidad y los profesionales sanitarios ponen en primer plano a la salud y las cuestiones sociales entre los miembros de la comunidad y las familias. Este modelo aborda estas cuestiones, creando nuevos valores relativos a la salud y formando un sistema social que mejora la calidad de vida y el apoyo social para hacer sostenible la atención sanitaria universal a través del proceso de construcción de alianzas con las comunidades. un modelo de alianza para CCP responde a los desafíos de los cambios sociales que afectan a la salud en general y al nuevo papel de las enfermeras de práctica avanzada en el sostenimiento de la Cobertura Universal en Salud (CUS).

Investigation of phase stability of novel equiatomic FeCoNiCuZn based-high entropy alloy prepared by mechanical alloying

NASA Astrophysics Data System (ADS)

Soni, Vinay Kumar; Sanyal, S.; Sinha, S. K.

2018-05-01

The present work reports the structural and phase stability analysis of equiatomic FeCoNiCuZn High entropy alloy (HEA) systems prepared by mechanical alloying (MA) method. In this research effort some 1287 alloy combinations were extensively studied to arrive at most favourable combination. FeCoNiCuZn based alloy system was selected on the basis of physiochemical parameters such as enthalpy of mixing (ΔHmix), entropy of mixing (ΔSmix), atomic size difference (ΔX) and valence electron concentration (VEC) such that it fulfils the formation criteria of stable multi component high entropy alloy system. In this context, we have investigated the effect of novel alloying addition in view of microstructure and phase formation aspect. XRD plots of the MA samples shows the formation of stable solid solution with FCC (Face Cantered Cubic) after 20 hr of milling time and no indication of any amorphous or intermetallic phase formation. Our results are in good agreement with calculation and analysis done on the basis of physiochemical parameters during selection of constituent elements of HEA.

Neem Leaf Glycoprotein Prophylaxis Transduces Immune Dependent Stop Signal for Tumor Angiogenic Switch within Tumor Microenvironment

PubMed Central

Banerjee, Saptak; Ghosh, Tithi; Barik, Subhasis; Das, Arnab; Ghosh, Sarbari; Bhuniya, Avishek

2014-01-01

We have reported that prophylactic as well as therapeutic administration of neem leaf glycoprotein (NLGP) induces significant restriction of solid tumor growth in mice. Here, we investigate whether the effect of such pretreatment (25µg/mice; weekly, 4 times) benefits regulation of tumor angiogenesis, an obligate factor for tumor progression. We show that NLGP pretreatment results in vascular normalization in melanoma and carcinoma bearing mice along with downregulation of CD31, VEGF and VEGFR2. NLGP pretreatment facilitates profound infiltration of CD8+ T cells within tumor parenchyma, which subsequently regulates VEGF-VEGFR2 signaling in CD31+ vascular endothelial cells to prevent aberrant neovascularization. Pericyte stabilization, VEGF dependent inhibition of VEC proliferation and subsequent vascular normalization are also experienced. Studies in immune compromised mice confirmed that these vascular and intratumoral changes in angiogenic profile are dependent upon active adoptive immunity particularly those mediated by CD8+ T cells. Accumulated evidences suggest that NLGP regulated immunomodulation is active in tumor growth restriction and normalization of tumor angiogenesis as well, thereby, signifying its clinical translation. PMID:25391149

DOE Office of Scientific and Technical Information (OSTI.GOV)

Potash, Peter J.; Bell, Eric B.; Harrison, Joshua J.

Predictive models for tweet deletion have been a relatively unexplored area of Twitter-related computational research. We first approach the deletion of tweets as a spam detection problem, applying a small set of handcrafted features to improve upon the current state-of-the- art in predicting deleted tweets. Next, we apply our approach to a dataset of deleted tweets that better reflects the current deletion rate. Since tweets are deleted for reasons beyond just the presence of spam, we apply topic modeling and text embeddings in order to capture the semantic content of tweets that can lead to tweet deletion. Our goal ismore » to create an effective model that has a low-dimensional feature space and is also language-independent. A lean model would be computationally advantageous processing high-volumes of Twitter data, which can reach 9,885 tweets per second. Our results show that a small set of spam-related features combined with word topics and character-level text embeddings provide the best f1 when trained with a random forest model. The highest precision of the deleted tweet class is achieved by a modification of paragraph2vec to capture author identity.« less

A Precise Measurement of the Deuteron Elastic Structure Function A(Q 2)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Honegger, Andrian

1999-12-07

During summer 1997 experiment 394-018 measured the deuteron tensor polarization in D(e,e'more » $$vec\\{d}$$) scattering in Hall C at Jefferson Laboratory. In a momentum transfer range between 0.66 and 1.8 (GeV=c) 2, with slight changes in the experimental setup, the collaboration performed six precision measurements of the deuteron structure function A(Q 2) in elastic D(e,e'd) scattering . Scattered electrons and recoil deuterons were detected in coincidence in the High Momentum Spectrometer and the recoil polarimeter POLDER, respectively. At every kinematics H(e,e') data were taken to study systematic effects of the measurement. These new precise measurements resolve discrepancies between older data sets and put significant constraints on existing models of the deuteron electromagnetic structure. This work was supported by the Swiss National Science Foundation, the French Centre National de la Recherche Scientifique and the Commissariat 'a l'Energie Atomique, the U.S. Department of Energy and the National Science Foundation and the K.C. Wong Foundation.« less

Neem leaf glycoprotein prophylaxis transduces immune dependent stop signal for tumor angiogenic switch within tumor microenvironment.

PubMed

Banerjee, Saptak; Ghosh, Tithi; Barik, Subhasis; Das, Arnab; Ghosh, Sarbari; Bhuniya, Avishek; Bose, Anamika; Baral, Rathindranath

2014-01-01

We have reported that prophylactic as well as therapeutic administration of neem leaf glycoprotein (NLGP) induces significant restriction of solid tumor growth in mice. Here, we investigate whether the effect of such pretreatment (25µg/mice; weekly, 4 times) benefits regulation of tumor angiogenesis, an obligate factor for tumor progression. We show that NLGP pretreatment results in vascular normalization in melanoma and carcinoma bearing mice along with downregulation of CD31, VEGF and VEGFR2. NLGP pretreatment facilitates profound infiltration of CD8+ T cells within tumor parenchyma, which subsequently regulates VEGF-VEGFR2 signaling in CD31+ vascular endothelial cells to prevent aberrant neovascularization. Pericyte stabilization, VEGF dependent inhibition of VEC proliferation and subsequent vascular normalization are also experienced. Studies in immune compromised mice confirmed that these vascular and intratumoral changes in angiogenic profile are dependent upon active adoptive immunity particularly those mediated by CD8+ T cells. Accumulated evidences suggest that NLGP regulated immunomodulation is active in tumor growth restriction and normalization of tumor angiogenesis as well, thereby, signifying its clinical translation.

Estimation of the prevalence of adverse drug reactions from social media.

PubMed

Nguyen, Thin; Larsen, Mark E; O'Dea, Bridianne; Phung, Dinh; Venkatesh, Svetha; Christensen, Helen

2017-06-01

This work aims to estimate the degree of adverse drug reactions (ADR) for psychiatric medications from social media, including Twitter, Reddit, and LiveJournal. Advances in lightning-fast cluster computing was employed to process large scale data, consisting of 6.4 terabytes of data containing 3.8 billion records from all the media. Rates of ADR were quantified using the SIDER database of drugs and side-effects, and an estimated ADR rate was based on the prevalence of discussion in the social media corpora. Agreement between these measures for a sample of ten popular psychiatric drugs was evaluated using the Pearson correlation coefficient, r, with values between 0.08 and 0.50. Word2vec, a novel neural learning framework, was utilized to improve the coverage of variants of ADR terms in the unstructured text by identifying syntactically or semantically similar terms. Improved correlation coefficients, between 0.29 and 0.59, demonstrates the capability of advanced techniques in machine learning to aid in the discovery of meaningful patterns from medical data, and social media data, at scale. Copyright © 2017 Elsevier B.V. All rights reserved.

A causa das estações do ano: modelos mentais

NASA Astrophysics Data System (ADS)

de Campos, J. A. S.; de Araujo, J. F. S.

2003-08-01

A década de 70 do século passado foi marcada pelo estudo das concepções alternativas que os alunos trazem para a sala de aula. A identificação destas concepções foi o ponto de partida para promover a mudança conceitual, onde as pré-concepções seriam trocadas pelas concepções científicas. Na década seguinte, surgiram muitas propostas de estratégias educacionais para facilitar esta troca, na sua maioria baseadas na idéia do conflito cognitivo, proposta por Piaget. Entretanto, os resultados pouco animadores conduziram à percepção de que a mudança conceitual é um processo mais complexo. Pelas idéias da Ciência Cognitiva, a mudança conceitual é uma mudança progressiva dos modelos mentais que o aluno tem sobre o mundo físico, através de enriquecimento e revisão. A causa das Estações do Ano é um tópico sobre o qual a maioria dos estudantes apresenta concepções alternativas. Os autores fizeram um levantamento sobre as pré-concepções encontradas em trabalhos sobre o tema (16 referências), procurando encontrar elementos comuns que indicassem a presença de modelos mentais específicos. As pré-concepções encontradas na literatura foram obtidas usando-se diversas metodologias (desde entrevistas clínicas até questionários de múltipla escolha) e envolvendo alunos e professores de diferentes regiões geográficas. A partir de uma análise aprofundada de cada trabalho, e utilizando-se a técnica das Redes Sistêmicas, chegou-se a conclusão que as diversas pré-concepções identificadas (em torno de 50), poderiam ser representadas por 6 modelos mentais, onde a explicação da causa das estações do ano tem um mecanismo causal responsável. Os mecanismos causais identificados foram: a dependência da distância, a dependência da orientação, a dependência conjunta da distância e orientação, a dependência da obstrução, a dependência da velocidade e a dependência da inclinação dos raios solares. Foram ainda identificadas associações alternativas, que são um conjunto de pré-concepções, onde não existe a idéia de um modelo científico completo mas, sim, fragmentos de observação do dia a dia das pessoas.

78 FR 58559 - United States

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-24

... license to ten Modelo Brand Beers, including Corona Extra, this country's bestselling imported beer and... failure of the government to discharge its duty, the Court, in making its public interest finding, should...

Sobre a largura da última superfície de espalhamento

NASA Astrophysics Data System (ADS)

Nobre, M. A. S.; Pires, N.; Lima, J. A. S.

2003-08-01

De acordo com o modelo do "Big-Bang", no universo primordial a matéria estava em equilíbrio térmico com a radiação. Com a expansão a temperatura da radiação cai. Quando a temperatura chega em torno dos 4.000K, os espalhamentos diminuem, começando a recombinação dos prótons e elétrons em Hidrogênio neutro (era conhecida como da recombinação). Ao final da recombinação, os fótons se propagam livremente sofrendo, em princípio, somente os efeitos do "redshift" cosmológico. Esses fótons nos alcançam hoje como a radiação cósmica de fundo (RCF), e parecem vir de uma superfície esférica ao nosso redor, tal que o raio dela é a distância que ele viajou desde seu último espalhamento na época da recombinação. Naturalmente, esse processo não ocorreu abruptamente, implicando na existência de uma largura no espaço dos "redshifts" que deve depender do modelo cosmológico específico e dos processos físicos considerados. Neste trabalho analisamos os efeitos de diferentes modelos - a saber, aqueles com decaimento do vácuo L(t), criação de matéria, quintessência e gás de Chaplygin - sobre a última superfície de espalhamento da RCF, em particular sua largura e a função visibilidade, que determina a probabilidade de um fóton ter tido seu último espalhamento num "redshift" z. No caso particular dos modelos com decaimento do vácuo, existe uma forte dependência da função visibilidade com L(t). Tais efeitos poderão ser testados através da análise dos resultados de experimentos mais precisos que estão atualmente em andamento, como por exemplo, o WMAP.

Los cambios en la velocidad de rotación terrestre y los fenómenos geomagnéticos

NASA Astrophysics Data System (ADS)

Gianibelli, J. C.

Uno de los aspectos importantes relativos a la geodinámica del interior terrestre es la correlación entre los eventos de cambio en la velocidad de rotación terrestre y los determinados en los elementos del campo geomagnético por ejemplo, la Declinación Magnética, o los coeficientes de los modelos matemáticos de representación global de dicho campo. En este trabajo se presentan los resultados de las características espectrales de los cambios observados en la longitud del día (ldd), y su relación con la estructura espectral de las coeficientes de los modelos matemáticos de campo denominados Campo Internacional Geomagnético de Referencia (CIGR). El intervalo estudiado comprende los últimos 100 años. Los resultados muestran una correlación en las bandas de 60 y 30 años, con posibles períodos mucho mayores que no son posibles determinar a partir de los modelos de CIRG. Se efectúa una simulación a partir de los resultados obtenidos por la aplicación del método de máxima entropía con longitudes del filtro predictor de error comprendida entre el 10% y el 95% de la longitud de la serie analizada. Se observan procesos sicrónicos y asincrónicos que, en muy largos intervalos de tiempos, podrían suponerse como caóticos.

Modelizacion, control e implementacion de un procesador energetico paralelo para aplicacion en sistemas multisalida

NASA Astrophysics Data System (ADS)

Ferreres Sabater, Agustin

Cualquier sistema electronico que incluya un procesado o tratamiento de la senal, y ademas, algun tipo de actuador mecanico generalmente necesita, como minimo, dos tensiones diferentes de alimentacion. Excluyendo los sistemas de alimentacion distribuida, la solucion tecnica mas utilizada para proporcionar dos o mas tensiones consiste en las fuentes de alimentacion multisalida. En una fuente de alimentacion multisalida los diferentes circuitos que conforman cada salida comparten un mismo transformador de potencia optimizando coste, masa, y volumen. Las ventajas obtenidas con este procedimiento tienen en su contra el efecto que sobre cada salida individual provocan las demas en su conjunto debido, principalmente, a los efectos de los elementos parasitos de los componentes. Un cambio de carga en una de las salidas produce un transitorio que es visto por todas las demas como un efecto de impedancia cruzada, y al final del transitorio, la tension de cada salida es diferente respecto a la que tenian antes del transitorio. Este ultimo resultado se conoce como regulacion cruzada. La disminucion de los efectos de la regulacion cruzada ha sido objeto de estudio durante los ultimos anos. El objetivo ha sido el desarrollo de distintas estrategias que permiten, desde disminuir los efectos de la regulacion cruzada hasta los niveles deseables, a eliminarla completamente. El resultado final suele suponer una penalizacion sobre el diseno del sistema directamente proporcional al grado de regulacion a conseguir en las distintas salidas. Entre las soluciones propuestas para eliminar la regulacion cruzada las tecnicas de post-regulacion se han consolidado como la opcion mas aceptada ya que, pueden aplicarse a cualquier convertidor y no suponen ninguna complejidad adicional a la hora de plantear el diseno. En esta Tesis Doctoral se abordara el estudio de la tecnica conocida como postregulacion mediante transformador controlado, que si bien se ha empleado en convertidores resonantes, su modelizacion, y aplicacion en convertidores PWM, esta aun por estudiar y valorar. El primer Capitulo consiste en una breve introduccion al problema de la regulacion cruzada y la impedancia cruzada para posteriormente describir las tecnicas de post-regulacion actualmente mas empleadas, con especial atencion al post-regulador con transformador controlado. El Capitulo segundo trata del estudio de las caracteristicas estaticas del postregulador con transformador controlado. Partiendo de los estudios disponibles sobre el postregulador se plantean mejoras en su modo de actuacion y se discuten tres alternativas diferentes para controlar el transformador. Las dos primeras consisten en emplear un convertidor auxiliar Boost en sus dos modos de funcionamiento, continuo y discontinuo. La tercera consiste en controlar el transformador con una tension PWM directamente, sin filtrado. Finalmente se comprueba experimentalmente, para el estado estacionario, el funcionamiento del post-regulador para cada uno de los tres metodos de control. El Capitulo tercero trata de la dinamica de la salida controlada con el post-regulador cuando este emplea un convertidor auxiliar tipo Boost. Mediante la tecnica de promediado de variables de estado se propone el modelo de pequena senal, tanto para el modo continuo como para el modo discontinuo de funcionamiento del convertidor auxiliar. Los resultados mas significativos de esta seccion son las expresiones analiticas de las impedancias cruzadas y de la impedancia de la salida post-regulada. Como complemento al modelo de pequena senal se plantea un modelo de gran senal implementado sobre el simulador Pspice. Con este nuevo modelo se reproducen los resultados obtenidos con el modelo de pequena senal y ademas es posible simular los transitorios en las tensiones de salida ante cambios de carga. La modelizacion del convertidor cuando el transformador se controla con una tension PWM sin filtrar es el objetivo del Capitulo 4. En las secciones siguientes del Capitulo se plantea el correspondiente modelo de gran senal aplicado a un nuevo prototipo experimental, de mayor tension de entrada y mayores corrientes de salida. El final del Capitulo contrasta los resultados experimentales con los teoricos confirmando la utilidad del modelo de gran senal como una herramienta basica de diseno. Finalmente, en el Capitulo 5, se presentan las conclusiones y la valoracion de los diferentes estudios plateados a lo largo de la Tesis Doctoral.

Elastoplasticidad anisotropa de metales en grandes deformaciones

NASA Astrophysics Data System (ADS)

Caminero Torija, Miguel Angel

El objetivo de este trabajo es el desarrollo de modelos y algoritmos numericos que simulen el comportamiento del material bajo estas condiciones en el contexto de programas de elementos finitos, dando como resultado predicciones mas precisas de los procesos de conformado y deformacion plastica en general. Para lograr este objetivo se han desarrollado diversas tareas destinadas a mejorar las predicciones en tres aspectos fundamentales. El primer aspecto consiste en la mejora de la descripcion del endurecimiento cinematico anisotropo en pequenas deformaciones, lo cual se ha realizado a traves de modelos y algoritmos implicitos de superficies multiples. Ha sido estudiada la consistencia de este tipo de modelos tanto si estan basados en una regla implicita similar a la de Mroz o en la regla de Prager. Ademas se han simulado los ensayos de Lamba y Sidebottom, obteniendo, en contra de la creencia general, muy buenas predicciones con la regla de Prager. Dichos modelos podrian ser extendidos de forma relativamente facil para considerar grandes deformaciones a traves de procedimientos en deformaciones logaritmicas, similares a los desarrollados en esta tesis y detallados a continuacion. El segundo aspecto consiste en la descripcion de la anisotropia elastoplastica inicial. Esto se ha conseguido mediante el desarrollo de modelos y algoritmos para plasticidad anisotropa en grandes deformaciones, bien ignorando la posible anisotropia elastica, bien considerandola simultaneamente con la anisotropia plastica. Para ello ha sido necesario desarrollar primero un nuevo algoritmo de elastoplasticidad anisotropa en pequenas deformaciones consistentemente linealizado y sin despreciar ningun termino, de tal forma que se conserve la convergencia cuadratica de los metodos de Newton. Este algoritmo en pequenas deformaciones ha servido para realizar la correccion plastica de dos algoritmos en grandes deformaciones. El primero de estos algoritmos es una variacion del clasico algoritmo de Eterovic y Bathe para incluir la posibilidad de plasticidad anisotropa con endurecimiento mixto. Este primer algoritmo esta restringido a casos de isotropia elastica. La isotropia elastica es una hipotesis bastante habitual en plasticidad anisotropa y tiene la ventaja de que permite el uso de formulaciones mixtas u/p. El segundo algoritmo, mas complejo y general, incluye la posibilidad de elasticidad anisotropa, plasticidad anisotropa y endurecimiento mixto. Este algoritmo supone una contribucion importante ya que esta basado en hipotesis comunmente aceptadas y utilizadas en elastoplasticidad isotropa: descomposicion multiplicativa del gradiente de deformaciones en parte elastica y parte plastica, descripcion hiperelastica sencilla en funcion de deformaciones logaritmicas e integracion exponencial que conserva el volumen. Ademas, la estructura final del algoritmo es modular y relativamente sencilla, consistiendo en un pre- y un postprocesador geometrico y una correccion plastica realizada en pequenas deformaciones. El algoritmo esta consistentemente linealizado para conservar la convergencia cuadratica asintotica de los metodos de Newton y la forma final que toma dicha linealizacion es similar al caso de isotropia elastoplastica implementado; consiste en el modulo tangente algoritmico de pequenas deformaciones sobre el que se aplica una transformacion para convertirlo en el de grandes deformaciones. Todos estos modelos han sido implementados en un codigo propio de elementos finitos denominado DULCINEA, el cual tiene formulaciones lagrangianas totales y actualizadas para grandes deformaciones. Una de las tareas necesarias para poder realizar las simulaciones, ha sido el estudio e implementacion de diferentes elementos que no sufran el bloqueo volumetrico severo que se observa en formulaciones estandar basadas en desplazamientos. Este bloqueo se debe a la condicion de quasi-incompresibilidad que imponen los modelos de plasticidad desviadores y consiste en una respuesta exageradamente rigida de la solucion obtenida por el metodo de los elementos finitos estandar. Entre los elementos implementados cabe destacar el basado en la formulacion mixta u/p, que contiene una interpolacion adicional de grados de libertad de presion. Estos grados de libertad adicionales habitualmente son internos al elemento en mecanica de solidos. En este trabajo se ha desarrollado e implementado en DULCINEA una familia de elementos tridimensionales mixtos en grandes deformaciones que incluye el caso particular BMIX 27/27/4, basado en la formulacion u/p, constituido por 27 nudos, con 27 puntos de integracion estandar y 4 grados de libertad de presiones, y que pasa la condicion Inf-Sup o de Babuska-Brezzi. Sin embargo, se ha observado que la formulacion u/p presenta ciertas limitaciones bajo las hipotesis conjuntas de anisotropia elastica y anisotropia plastica. (Abstract shortened by UMI.)

Development of nonhuman adenoviruses as vaccine vectors

PubMed Central

Bangari, Dinesh S.; Mittal, Suresh K.

2006-01-01

Human adenoviral (HAd) vectors have demonstrated great potential as vaccine vectors. Preclinical and clinical studies have demonstrated the feasibility of vector design, robust antigen expression and protective immunity using this system. However, clinical use of adenoviral vectors for vaccine purposes is anticipated to be limited by vector immunity that is either preexisting or develops rapidly following the first inoculation with adenoviral vectors. Vector immunity inactivates the vector particles and rapidly removes the transduced cells, thereby limiting the duration of transgene expression. Due to strong vector immunity, subsequent use of the same vector is usually less efficient. In order to circumvent this limitation, nonhuman adenoviral vectors have been proposed as alternative vectors. In addition to eluding HAd immunity, these vectors possess most of the attractive features of HAd vectors. Several replication-competent or replication-defective nonhuman adenoviral vectors have been developed and investigated for their potential as vaccine delivery vectors. Here, we review recent advances in the design and characterization of various nonhuman adenoviral vectors, and discuss their potential applications for human and animal vaccination. PMID:16297508

Análise da medição do raio solar em ultravioleta

NASA Astrophysics Data System (ADS)

Saraiva, A. C. V.; Giménez de Castro, C. G.; Costa, J. E. R.; Selhorst, C. L.; Simões, P. J. A.

2003-08-01

A medição acurada do raio solar em qualquer banda do espectro eletromagnético é de relevância na formulação e calibração de modelos da estrutura e atmosfera solar. Esses modelos atribuem emissão do contínuo do Sol calmo em microondas à mesma região da linha Ha do Hell. Apresentamos a medição do raio solar em UV com imagens do EIT (Extreme Ultraviolet Image Telescope) entre 1996 e 2002, no comprimento de onda 30,9 nm (Ha do Hell), que se forma na região de transição/cromosfera solar. A técnica utilizada para o cálculo do raio UV foi baseada na transformada Wavelet B3spline. Fizemos um banco de dados com 1 imagem por dia durante o período citado. Obtivemos como resultado o raio médio da ordem de 975.61" e uma diminuição do mesmo para o período citado variando em média -0,45" /ano. Comparamos estes dados com os valores obtidos pelo ROI (Radio Observatório de Itapetinga) em 22/48 GHz e Nobeyama Radio Heliograph em 17 GHz mostrando que os raios médios são muito próximos o que indica que a região de formação nessas freqüências é a mesma conforme os modelos. Comparamos os resultados também com outros índices de atividade solar.

Vaxvec: The first web-based recombinant vaccine vector database and its data analysis

PubMed Central

Deng, Shunzhou; Martin, Carly; Patil, Rasika; Zhu, Felix; Zhao, Bin; Xiang, Zuoshuang; He, Yongqun

2015-01-01

A recombinant vector vaccine uses an attenuated virus, bacterium, or parasite as the carrier to express a heterologous antigen(s). Many recombinant vaccine vectors and related vaccines have been developed and extensively investigated. To compare and better understand recombinant vectors and vaccines, we have generated Vaxvec (http://www.violinet.org/vaxvec), the first web-based database that stores various recombinant vaccine vectors and those experimentally verified vaccines that use these vectors. Vaxvec has now included 59 vaccine vectors that have been used in 196 recombinant vector vaccines against 66 pathogens and cancers. These vectors are classified to 41 viral vectors, 15 bacterial vectors, 1 parasitic vector, and 1 fungal vector. The most commonly used viral vaccine vectors are double-stranded DNA viruses, including herpesviruses, adenoviruses, and poxviruses. For example, Vaxvec includes 63 poxvirus-based recombinant vaccines for over 20 pathogens and cancers. Vaxvec collects 30 recombinant vector influenza vaccines that use 17 recombinant vectors and were experimentally tested in 7 animal models. In addition, over 60 protective antigens used in recombinant vector vaccines are annotated and analyzed. User-friendly web-interfaces are available for querying various data in Vaxvec. To support data exchange, the information of vaccine vectors, vaccines, and related information is stored in the Vaccine Ontology (VO). Vaxvec is a timely and vital source of vaccine vector database and facilitates efficient vaccine vector research and development. PMID:26403370

MOBRAL: Un Modelo para la Educacion de Adultos?

ERIC Educational Resources Information Center

Convergence, 1974

1974-01-01

Written in Spanish, the article explains that expanding an adult basic education program, the Brazilian Literacy Movement (MOBRAL), necessitates considering the social orientation of MOBRAL in the context of Brazil and of Latin America as a whole. (AG)

DISE Summary Report (1992)

DTIC Science & Technology

1994-03-01

Specification and Network Time Protocol(NTP) over the Implementation. RFC-o 119, Network OSI Remote Operations Service. RFC- Working Group, September...approximately ISIS implements a powerful model of 94% of the total computation time. distributed computation known as modelo Timing results are

Implementación de un modelo de capacitación multimedial para brindar orientación alimentaria a los beneficiarios de un programa de ayuda social en México.

PubMed

Amaya-Castellanos, Maritza Alejandra; Morales-Ruan, María Del Carmen; Uribe-Carvajal, Rebeca; Jiménez-Aguilar, Alejandra; Salazar-Coronel, Araceli Apolonia; Martínez-Tapia, Brenda; Shamah-Levy, Teresa

2018-03-01

Introducción: Se implementó un modelo de capacitación en orientación alimentaria para la población beneficiaria y el personal operativo del Programa de Abasto Rural (PAR) de Diconsa, el cual es una iniciativa social de ayuda alimentaria que abastece productos básicos y complementarios, además de brindar capacitación en localidades de alta marginación en México. Objetivo: Documentar la utilización de la Metodología de Capacitación Multimedial (MCM) en el desarrollo de un esquema de capacitación sobre orientación alimentaria y su implementación en la población beneficiaria del PAR, a través de la propia estructura operativa del PAR. Metodología: El modelo se fundamenta en la MCM, integrada por cuatro elementos didácticos e indivisibles que conforman el paquete pedagógico multimedial (PPM), compuesto a su vez por tres videos y rotafolios, material impreso, prácticas y las relaciones interpersonales. Los ejes temáticos fueron: alimentación correcta para una vida saludable, alimentación materno-infantil, elecciones saludables y gasto familiar. El modelo fue replicado en cascada en los tres niveles operativos del PAR (responsables de capacitación, supervisores operativos y beneficiarios del PAR), con un componente de multiplicación horizontal, e implementado como piloto en cuatro estados de México. Resultados: Se observó un cambio positivo sobre los conocimientos en alimentación correcta en todos los niveles de capacitación, principalmente en los beneficiarios del PAR. La evaluación del proceso mostró conocimientos previos de los responsables de capacitación en los temas, buen desempeño como facilitadores, y habilidades de presentación y manejo del grupo de los supervisores operativos. A partir de las evaluaciones y del acompañamiento en la prueba piloto, fueron modificados las actividades, las estrategias y los materiales educativos del PPM. Conclusiones: La capacitación multimedial y la educación nutricional promueven procesos de cambio y desarrollo comunitario, posibles a través de la toma de conciencia y la puesta en práctica de acciones que favorecen la salud.

Versatile generation of optical vector fields and vector beams using a non-interferometric approach.

PubMed

Tripathi, Santosh; Toussaint, Kimani C

2012-05-07

We present a versatile, non-interferometric method for generating vector fields and vector beams which can produce all the states of polarization represented on a higher-order Poincaré sphere. The versatility and non-interferometric nature of this method is expected to enable exploration of various exotic properties of vector fields and vector beams. To illustrate this, we study the propagation properties of some vector fields and find that, in general, propagation alters both their intensity and polarization distribution, and more interestingly, converts some vector fields into vector beams. In the article, we also suggest a modified Jones vector formalism to represent vector fields and vector beams.

VectorBase: a home for invertebrate vectors of human pathogens

PubMed Central

Lawson, Daniel; Arensburger, Peter; Atkinson, Peter; Besansky, Nora J.; Bruggner, Robert V.; Butler, Ryan; Campbell, Kathryn S.; Christophides, George K.; Christley, Scott; Dialynas, Emmanuel; Emmert, David; Hammond, Martin; Hill, Catherine A.; Kennedy, Ryan C.; Lobo, Neil F.; MacCallum, M. Robert; Madey, Greg; Megy, Karine; Redmond, Seth; Russo, Susan; Severson, David W.; Stinson, Eric O.; Topalis, Pantelis; Zdobnov, Evgeny M.; Birney, Ewan; Gelbart, William M.; Kafatos, Fotis C.; Louis, Christos; Collins, Frank H.

2007-01-01

VectorBase () is a web-accessible data repository for information about invertebrate vectors of human pathogens. VectorBase annotates and maintains vector genomes providing an integrated resource for the research community. Currently, VectorBase contains genome information for two organisms: Anopheles gambiae, a vector for the Plasmodium protozoan agent causing malaria, and Aedes aegypti, a vector for the flaviviral agents causing Yellow fever and Dengue fever. PMID:17145709

Vaxvec: The first web-based recombinant vaccine vector database and its data analysis.

PubMed

Deng, Shunzhou; Martin, Carly; Patil, Rasika; Zhu, Felix; Zhao, Bin; Xiang, Zuoshuang; He, Yongqun

2015-11-27

A recombinant vector vaccine uses an attenuated virus, bacterium, or parasite as the carrier to express a heterologous antigen(s). Many recombinant vaccine vectors and related vaccines have been developed and extensively investigated. To compare and better understand recombinant vectors and vaccines, we have generated Vaxvec (http://www.violinet.org/vaxvec), the first web-based database that stores various recombinant vaccine vectors and those experimentally verified vaccines that use these vectors. Vaxvec has now included 59 vaccine vectors that have been used in 196 recombinant vector vaccines against 66 pathogens and cancers. These vectors are classified to 41 viral vectors, 15 bacterial vectors, 1 parasitic vector, and 1 fungal vector. The most commonly used viral vaccine vectors are double-stranded DNA viruses, including herpesviruses, adenoviruses, and poxviruses. For example, Vaxvec includes 63 poxvirus-based recombinant vaccines for over 20 pathogens and cancers. Vaxvec collects 30 recombinant vector influenza vaccines that use 17 recombinant vectors and were experimentally tested in 7 animal models. In addition, over 60 protective antigens used in recombinant vector vaccines are annotated and analyzed. User-friendly web-interfaces are available for querying various data in Vaxvec. To support data exchange, the information of vaccine vectors, vaccines, and related information is stored in the Vaccine Ontology (VO). Vaxvec is a timely and vital source of vaccine vector database and facilitates efficient vaccine vector research and development. Copyright © 2015 Elsevier Ltd. All rights reserved.

Algorithmic Classification of Five Characteristic Types of Paraphasias.

PubMed

Fergadiotis, Gerasimos; Gorman, Kyle; Bedrick, Steven

2016-12-01

This study was intended to evaluate a series of algorithms developed to perform automatic classification of paraphasic errors (formal, semantic, mixed, neologistic, and unrelated errors). We analyzed 7,111 paraphasias from the Moss Aphasia Psycholinguistics Project Database (Mirman et al., 2010) and evaluated the classification accuracy of 3 automated tools. First, we used frequency norms from the SUBTLEXus database (Brysbaert & New, 2009) to differentiate nonword errors and real-word productions. Then we implemented a phonological-similarity algorithm to identify phonologically related real-word errors. Last, we assessed the performance of a semantic-similarity criterion that was based on word2vec (Mikolov, Yih, & Zweig, 2013). Overall, the algorithmic classification replicated human scoring for the major categories of paraphasias studied with high accuracy. The tool that was based on the SUBTLEXus frequency norms was more than 97% accurate in making lexicality judgments. The phonological-similarity criterion was approximately 91% accurate, and the overall classification accuracy of the semantic classifier ranged from 86% to 90%. Overall, the results highlight the potential of tools from the field of natural language processing for the development of highly reliable, cost-effective diagnostic tools suitable for collecting high-quality measurement data for research and clinical purposes.

Short text sentiment classification based on feature extension and ensemble classifier

NASA Astrophysics Data System (ADS)

Liu, Yang; Zhu, Xie

2018-05-01

With the rapid development of Internet social media, excavating the emotional tendencies of the short text information from the Internet, the acquisition of useful information has attracted the attention of researchers. At present, the commonly used can be attributed to the rule-based classification and statistical machine learning classification methods. Although micro-blog sentiment analysis has made good progress, there still exist some shortcomings such as not highly accurate enough and strong dependence from sentiment classification effect. Aiming at the characteristics of Chinese short texts, such as less information, sparse features, and diverse expressions, this paper considers expanding the original text by mining related semantic information from the reviews, forwarding and other related information. First, this paper uses Word2vec to compute word similarity to extend the feature words. And then uses an ensemble classifier composed of SVM, KNN and HMM to analyze the emotion of the short text of micro-blog. The experimental results show that the proposed method can make good use of the comment forwarding information to extend the original features. Compared with the traditional method, the accuracy, recall and F1 value obtained by this method have been improved.

New cancer-treatment model of photodynamic therapy combined with a type I topoisomerase inhibitor, CPT-11, against HeLa cell tumors in nude mice used by OPO parametric tunable laser

NASA Astrophysics Data System (ADS)

Yoshida, Takato O.; Matsuzawa, Eiji; Matsuo, Tetsumichi; Koide, Yukio; Terakawa, Susumu; Yokokura, Teruo; Hirano, Toru

1995-03-01

A new cancer-treatment model, photodynamic therapy (PDT) combined with a type I topoisomerase inhibitor, camptothecin derivative (CPT-11), against HeLa cell tumors in BALB/c nude mice has been developed using a wide-band tunable coherent light source operated on optical parametric oscillation (OPO parametric tunable laser). The Photosan-3 PDT and CPT-11 combined therapy was remarkably effective, that is the inhibition rate (I.R.) 40 - 80%, as compared to PDT only in vivo. The analysis of HpD (Photosan-3) and CPT-11 effects on cultured HeLa cells in vitro has been studied by a video-enhanced contrast differential interference contrast microscope (VEC-DIC). Photosan-3 with 600 nm light killed cells by mitochondrial damage within 50 min, but not with 700 nm light. CPT-11 with 700 - 400 nm light killed cells within 50 min after nucleolus damage appeared after around 30 min. The localization of CPT-11 in cells was observed as fluorescence images in the nucleus, particularly the nucleoral area produced clear images using an Argus 100.

AltiVec performance increases for autonomous robotics for the MARSSCAPE architecture program

NASA Astrophysics Data System (ADS)

Gothard, Benny M.

2002-02-01

One of the main tall poles that must be overcome to develop a fully autonomous vehicle is the inability of the computer to understand its surrounding environment to a level that is required for the intended task. The military mission scenario requires a robot to interact in a complex, unstructured, dynamic environment. Reference A High Fidelity Multi-Sensor Scene Understanding System for Autonomous Navigation The Mobile Autonomous Robot Software Self Composing Adaptive Programming Environment (MarsScape) perception research addresses three aspects of the problem; sensor system design, processing architectures, and algorithm enhancements. A prototype perception system has been demonstrated on robotic High Mobility Multi-purpose Wheeled Vehicle and All Terrain Vehicle testbeds. This paper addresses the tall pole of processing requirements and the performance improvements based on the selected MarsScape Processing Architecture. The processor chosen is the Motorola Altivec-G4 Power PC(PPC) (1998 Motorola, Inc.), a highly parallized commercial Single Instruction Multiple Data processor. Both derived perception benchmarks and actual perception subsystems code will be benchmarked and compared against previous Demo II-Semi-autonomous Surrogate Vehicle processing architectures along with desktop Personal Computers(PC). Performance gains are highlighted with progress to date, and lessons learned and future directions are described.

Quantitative analysis of cardiovascular MR images.

PubMed

van der Geest, R J; de Roos, A; van der Wall, E E; Reiber, J H

1997-06-01

The diagnosis of cardiovascular disease requires the precise assessment of both morphology and function. Nearly all aspects of cardiovascular function and flow can be quantified nowadays with fast magnetic resonance (MR) imaging techniques. Conventional and breath-hold cine MR imaging allow the precise and highly reproducible assessment of global and regional left ventricular function. During the same examination, velocity encoded cine (VEC) MR imaging provides measurements of blood flow in the heart and great vessels. Quantitative image analysis often still relies on manual tracing of contours in the images. Reliable automated or semi-automated image analysis software would be very helpful to overcome the limitations associated with the manual and tedious processing of the images. Recent progress in MR imaging of the coronary arteries and myocardial perfusion imaging with contrast media, along with the further development of faster imaging sequences, suggest that MR imaging could evolve into a single technique ('one stop shop') for the evaluation of many aspects of heart disease. As a result, it is very likely that the need for automated image segmentation and analysis software algorithms will further increase. In this paper the developments directed towards the automated image analysis and semi-automated contour detection for cardiovascular MR imaging are presented.

Theoretical and experimental evidence of level repulsion states and evanescent modes in sonic crystal stubbed waveguides

NASA Astrophysics Data System (ADS)

Romero-García, V.; Vasseur, J. O.; Garcia-Raffi, L. M.; Hladky-Hennion, A. C.

2012-02-01

The complex band structures calculated using the extended plane wave expansion (EPWE) reveal the presence of evanescent modes in periodic systems, never predicted by the classical \\omega(\\vec {k}) methods, providing novel interpretations of several phenomena as well as a complete picture of the system. In this work, we theoretically and experimentally observe that in the ranges of frequencies where a deaf band is traditionally predicted, an evanescent mode with excitable symmetry appears, changing drastically the interpretation of the transmission properties. On the other hand, the simplicity of the sonic crystals in which only the longitudinal polarization can be excited is used to interpret, without loss of generality, the level repulsion between symmetric and antisymmetric bands in sonic crystals as the presence of an evanescent mode connecting both repelled bands. These evanescent modes, obtained using EPWE, explain both the attenuation produced in this range of frequencies and the transfer of symmetry from one band to the other in good agreement with both experimental results and multiple scattering predictions. Thus, the evanescent properties of the periodic system have been revealed to be necessary for the design of new acoustic and electromagnetic applications based on periodicity.

Parameter-Space Survey of Linear G-mode and Interchange in Extended Magnetohydrodynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Howell, E. C.; Sovinec, C. R.

The extended magnetohydrodynamic stability of interchange modes is studied in two configurations. In slab geometry, a local dispersion relation for the gravitational interchange mode (g-mode) with three different extensions of the MHD model [P. Zhu, et al., Phys. Rev. Lett. 101, 085005 (2008)] is analyzed. Our results delineate where drifts stablize the g-mode with gyroviscosity alone and with a two-fluid Ohm’s law alone. Including the two-fluid Ohm’s law produces an ion drift wave that interacts with the g-mode. This interaction then gives rise to a second instability at finite k y. A second instability is also observed in numerical extended MHD computations of linear interchange in cylindrical screw-pinch equilibria, the second configuration. Particularly with incomplete models, this mode limits the regions of stability for physically realistic conditions. But, applying a consistent two-temperature extended MHD model that includes the diamagnetic heat flux density (more » $$\\vec{q}$$ *) makes the onset of the second mode occur at larger Hall parameter. For conditions relevant to the SSPX experiment [E.B. Hooper, Plasma Phys. Controlled Fusion 54, 113001 (2012)], significant stabilization is observed for Suydam parameters as large as unity (D s≲1).« less

Parameter-Space Survey of Linear G-mode and Interchange in Extended Magnetohydrodynamics

DOE PAGES

Howell, E. C.; Sovinec, C. R.

2017-09-11

The extended magnetohydrodynamic stability of interchange modes is studied in two configurations. In slab geometry, a local dispersion relation for the gravitational interchange mode (g-mode) with three different extensions of the MHD model [P. Zhu, et al., Phys. Rev. Lett. 101, 085005 (2008)] is analyzed. Our results delineate where drifts stablize the g-mode with gyroviscosity alone and with a two-fluid Ohm’s law alone. Including the two-fluid Ohm’s law produces an ion drift wave that interacts with the g-mode. This interaction then gives rise to a second instability at finite k y. A second instability is also observed in numerical extended MHD computations of linear interchange in cylindrical screw-pinch equilibria, the second configuration. Particularly with incomplete models, this mode limits the regions of stability for physically realistic conditions. But, applying a consistent two-temperature extended MHD model that includes the diamagnetic heat flux density (more » $$\\vec{q}$$ *) makes the onset of the second mode occur at larger Hall parameter. For conditions relevant to the SSPX experiment [E.B. Hooper, Plasma Phys. Controlled Fusion 54, 113001 (2012)], significant stabilization is observed for Suydam parameters as large as unity (D s≲1).« less

Could we use beamlets as a tool for remote sensing of the magnetotail?

NASA Astrophysics Data System (ADS)

Dolgonosov, Maxim; Zelenyi, Lev; Zimbardo, Gaetano; Perri, Silvia; Kovrazhkin, Rostislav

2012-07-01

In our presentation we are going to raise a question of exploiting beamlets for remote sensing of magnetotail. There is a long history of investigation of particle dynamics and features of distribution functions with prescribed electric and magnetic fields that could be measured by spacecrafts. But we would like to focus our attention on small part of this story and study in detail the behavior of ion the vicinity of the current sheet. Burkhart and Chen [Burkhart and Chen, 1991,JGR] employed the modified Harris model of the current sheet magnetic field [vec{B}=B_{0} tanh (z/L)vec{e}_{x} +B_{z} vec{e}_{z} ] and found a signature of nonlinear particle dynamics and an underlying partitioning of phase space that manifests itself as a series of peaks in the ion distribution function. The separation between the peaks is proportional to the fourth root of the particle energy and quantities that describe the current sheet structure. Formation of these peaks in the ion distribution function was explained on the basis resonant condition proposed by Buchner and Zelenyi [Buchner and Zelenyi,1989, JGR]. The non-adiabatic dynamics of the ions at vicinity of equatorial plane can be characterized by the action integral I_{z} =1/2 π \\oint \\dot{z}dz , which serves as an approximate integral of motion [Sonnerup, 1971]. Chaos is generated by the jumps Δ I_{z} of this invariant which accompany the particle crossing of the current sheet, which can lead both to the almost regular (field-aligned) motion of particles and to the capture of particles in the center of the current sheet, due to the unavoidable chaotic scattering. However, a subset of the ``regularity'' regions can exist in the physical space for certain combinations of current sheet parameters. Successive jumps of the adiabatic invariant Iz within these regions at the entry of particle into the current sheet and its exit from the current sheet, in the first approximation compensate each other, and ions ejected from these regions form almost monoenergetic highly accelerated and spatially localized ion beams, the so-called beamlets. The quasi-stationary dawn-dusk electric field Ey in the magnetotail accelerates ions between these jumps [Buchner and Zelenyi, 1990; Zelenyi et al., 2006a; Grigorenko et al., 2007]. The sites of acceleration depend on the value of Bn, and for a typical energy of the ions coming from the mantle, the resonance condition is satisfied at a number of discrete positions downtail. Zelenyi et al. [Zelenyi et al., 2007, JETP Letters] found the universal scaling characterizing the chain of these "regularity" regions. This ``law'' gives a relation between the typical beamlet energy WN and corresponding number of resonant region N: W_{N} =4/3 log N. Later Dolgonosov et al. [Dolgonosov et al., 2010, JGR] modified ``universal'' scaling and showed that to study experimentally observed beamlets one should take into account presence of the electric field perpendicular to the plane of the current sheet. On the basis of this paper [Kovrakhin et al., 2012, JETP Letters] it was analyzed spacecraft data (Cluster and Interball) to study properties of thin current sheets. Evidently, nonlinear particle dynamic result to the generation of the regularity ``island'' with some characteristic features. In the paper of Zelenyi et al. [Zelenyi et al, 2006, GRL] modulation of the normal component of the magnetic field under influence of self-consistent currents of particles was investigated. Peaks of Bz modulation nearly coincided with ``regularity'' islands. This result indicates on the fact that turbulence in the plasma sheet could be resulted from the nonlinear particle dynamic and properties of these ``noise'' are governed by features of particle motion. Thereby influence of ``noise'' constrains exploiting beamlets for remote sensing. It is also natural to ask what happens with these ``resonant'' regions under influence of external noise (or externally driven turbulence). Experimental observation of the magnetic field in the plasma sheet indicate on the permanent perturbation of the magnetic field and this perturbation could be very significant δBz ˜Bz. At the same time measurements of beamlets at the PSBL show that beamlets are long living structures [Grigorenko, 2003, JETP Letters]. What is the value of the magnetic field perturbation that could destroy generation of beamlets? In our report we are going to discuss current sheet properties obtained from beamlets analysis and natural restrictions imposed by turbulence.

Autofrecuencias de las ecuaciones de Helmholtz y Liouville para un modelo de tierra tipo Jeffreys simplificado.

NASA Astrophysics Data System (ADS)

Sevilla, M. J.; González-Camacho, A.

The authors obtain expressions for the free frequencies of polar motion for an ellipsoidal, rotating and perturbed earth model constituted by an elastic mantle with an homogeneous liquid core of additional simple motion.

Complex matrix multiplication operations with data pre-conditioning in a high performance computing architecture

DOEpatents

Eichenberger, Alexandre E; Gschwind, Michael K; Gunnels, John A

2014-02-11

Mechanisms for performing a complex matrix multiplication operation are provided. A vector load operation is performed to load a first vector operand of the complex matrix multiplication operation to a first target vector register. The first vector operand comprises a real and imaginary part of a first complex vector value. A complex load and splat operation is performed to load a second complex vector value of a second vector operand and replicate the second complex vector value within a second target vector register. The second complex vector value has a real and imaginary part. A cross multiply add operation is performed on elements of the first target vector register and elements of the second target vector register to generate a partial product of the complex matrix multiplication operation. The partial product is accumulated with other partial products and a resulting accumulated partial product is stored in a result vector register.

Vector adaptive predictive coder for speech and audio

NASA Technical Reports Server (NTRS)

Chen, Juin-Hwey (Inventor); Gersho, Allen (Inventor)

1990-01-01

A real-time vector adaptive predictive coder which approximates each vector of K speech samples by using each of M fixed vectors in a first codebook to excite a time-varying synthesis filter and picking the vector that minimizes distortion. Predictive analysis for each frame determines parameters used for computing from vectors in the first codebook zero-state response vectors that are stored at the same address (index) in a second codebook. Encoding of input speech vectors s.sub.n is then carried out using the second codebook. When the vector that minimizes distortion is found, its index is transmitted to a decoder which has a codebook identical to the first codebook of the decoder. There the index is used to read out a vector that is used to synthesize an output speech vector s.sub.n. The parameters used in the encoder are quantized, for example by using a table, and the indices are transmitted to the decoder where they are decoded to specify transfer characteristics of filters used in producing the vector s.sub.n from the receiver codebook vector selected by the vector index transmitted.

Method and apparatus for optimized processing of sparse matrices

DOEpatents

Taylor, Valerie E.

1993-01-01

A computer architecture for processing a sparse matrix is disclosed. The apparatus stores a value-row vector corresponding to nonzero values of a sparse matrix. Each of the nonzero values is located at a defined row and column position in the matrix. The value-row vector includes a first vector including nonzero values and delimiting characters indicating a transition from one column to another. The value-row vector also includes a second vector which defines row position values in the matrix corresponding to the nonzero values in the first vector and column position values in the matrix corresponding to the column position of the nonzero values in the first vector. The architecture also includes a circuit for detecting a special character within the value-row vector. Matrix-vector multiplication is executed on the value-row vector. This multiplication is performed by multiplying an index value of the first vector value by a column value from a second matrix to form a matrix-vector product which is added to a previous matrix-vector product.

Comparative seroprevalence and immunogenicity of six rare serotype recombinant adenovirus vaccine vectors from subgroups B and D.

PubMed

Abbink, Peter; Lemckert, Angelique A C; Ewald, Bonnie A; Lynch, Diana M; Denholtz, Matthew; Smits, Shirley; Holterman, Lennart; Damen, Irma; Vogels, Ronald; Thorner, Anna R; O'Brien, Kara L; Carville, Angela; Mansfield, Keith G; Goudsmit, Jaap; Havenga, Menzo J E; Barouch, Dan H

2007-05-01

Recombinant adenovirus serotype 5 (rAd5) vector-based vaccines are currently being developed for both human immunodeficiency virus type 1 and other pathogens. The potential limitations associated with rAd5 vectors, however, have led to the construction of novel rAd vectors derived from rare Ad serotypes. Several rare serotype rAd vectors have already been described, but a detailed comparison of multiple rAd vectors from subgroups B and D has not previously been reported. Such a comparison is critical for selecting optimal rAd vectors for advancement into clinical trials. Here we describe the construction of three novel rAd vector systems from Ad26, Ad48, and Ad50. We report comparative seroprevalence and immunogenicity studies involving rAd11, rAd35, and rAd50 vectors from subgroup B; rAd26, rAd48, and rAd49 vectors from subgroup D; and rAd5 vectors from subgroup C. All six rAd vectors from subgroups B and D exhibited low seroprevalence in a cohort of 200 individuals from sub-Saharan Africa, and they elicited Gag-specific cellular immune responses in mice both with and without preexisting anti-Ad5 immunity. The rAd vectors from subgroup D were also evaluated using rhesus monkeys and were shown to be immunogenic after a single injection. The rAd26 vectors proved the most immunogenic among the rare serotype rAd vectors studied, although all rare serotype rAd vectors were still less potent than rAd5 vectors in the absence of anti-Ad5 immunity. These studies substantially expand the portfolio of rare serotype rAd vectors that may prove useful as vaccine vectors for the developing world.

Optimum instantaneous impulsive orbital injection to attain a specified asymptotic velocity vector.

NASA Technical Reports Server (NTRS)

Bean, W. C.

1971-01-01

A nalysis of the necessary conditions of Battin for instantaneous orbital injection, with consideration of the uniqueness of his solution, and of the further problem which arises in the degenerate case when radius vector and asymptotic vector are separated by 180 deg. It is shown that when the angular separation between radius vector and asymptotic velocity vector satisfies theta not equal to 180 deg, there are precisely two insertion-velocity vectors which permit attainment of the target asymptotic velocity vector, one yielding posigrade, the other retrograde motion. When theta equals to 180 deg, there is a family of insertion-velocity vectors which permit attainment of a specified asymptotic velocity vector with a unique insertion-velocity vector for every arbitrary orientation of a target unit angular momentum vector.

High-efficiency Transduction of Rhesus Hematopoietic Repopulating Cells by a Modified HIV1-based Lentiviral Vector

PubMed Central

Uchida, Naoya; Hargrove, Phillip W.; Lap, Coen J.; Evans, Molly E.; Phang, Oswald; Bonifacino, Aylin C.; Krouse, Allen E.; Metzger, Mark E.; Nguyen, Anh-Dao; Hsieh, Matthew M.; Wolfsberg, Tyra G.; Donahue, Robert E.; Persons, Derek A.; Tisdale, John F.

2012-01-01

Human immunodeficiency virus type 1 (HIV1) vectors poorly transduce rhesus hematopoietic cells due to species-specific restriction factors, including the tripartite motif-containing 5 isoformα (TRIM5α) which targets the HIV1 capsid. We previously developed a chimeric HIV1 (χHIV) vector system wherein the vector genome is packaged with the simian immunodeficiency virus (SIV) capsid for efficient transduction of both rhesus and human CD34+ cells. To evaluate whether χHIV vectors could efficiently transduce rhesus hematopoietic repopulating cells, we performed a competitive repopulation assay in rhesus macaques, in which half of the CD34+ cells were transduced with standard SIV vectors and the other half with χHIV vectors. As compared with SIV vectors, χHIV vectors achieved higher vector integration, and the transgene expression rates were two- to threefold higher in granulocytes and red blood cells and equivalent in lymphocytes and platelets for 2 years. A recipient of χHIV vector-only transduced cells reached up to 40% of transgene expression rates in granulocytes and lymphocytes and 20% in red blood cells. Similar to HIV1 and SIV vectors, χHIV vector frequently integrated into gene regions, especially into introns. In summary, our χHIV vector demonstrated efficient transduction for rhesus long-term repopulating cells, comparable with SIV vectors. This χHIV vector should allow preclinical testing of HIV1-based therapeutic vectors in large animal models. PMID:22871664

Comparação de modelos para o cálculo de perturbações orbitais devidas à maré terrestre

NASA Astrophysics Data System (ADS)

Vieira Pinto, J.; Vilhena de Moraes, R.

2003-08-01

Aplicações recentes de satélites artificiais com finalidades geodinâmicas requerem órbitas determinadas com bastante precisão. Em particular marés terrestres influenciam o potencial terrestre causando perturbações adicionais no movimento de satélites artificiais, as quais tem sido medidas por diversos processos. A atração exercida pela lua e pelo sol sobre a terra produz deslocamentos elásticos em seu interior e uma protuberância em sua superfície. O resultado é uma pequena variação na distribuição da massa na terra, consequentemente no geopotencial. As perturbações nos elementos orbitais de satélites artificiais terrestres devidas a maré terrestre podem ser estudadas a partir das equações de Lagrange, considerando-se um conveniente potencial. Por outro lado, como tem sido feito pelo IERS, as mudanças induzidas pela maré terrestre no geopotencial podem ser convenientemente modeladas como variações nos coeficientes Cnm e Snm do geopotencial. As duas teorias ainda não foram comparados para um mesmo satélite. Neste trabalho são apresentadas e comparadas as variações de longo período e seculares nas perturbações orbitais devidas à maré terrestre, calculadas por um modelo simples, o de Kozai, e pelo modelo do IERS. Resultados preliminares mostram, para os satélites SCD2 e CBERS1, e para a Lua em movimento elíptico e precessionando, as perturbações seculares no argumento do perigeu e na longitude do nodo ascendente.

Definition of Contravariant Velocity Components

NASA Technical Reports Server (NTRS)

Hung, Ching-moa; Kwak, Dochan (Technical Monitor)

2002-01-01

In this paper we have reviewed the basics of tensor analysis in an attempt to clarify some misconceptions regarding contravariant and covariant vector components as used in fluid dynamics. We have indicated that contravariant components are components of a given vector expressed as a unique combination of the covariant base vector system and, vice versa, that the covariant components are components of a vector expressed with the contravariant base vector system. Mathematically, expressing a vector with a combination of base vector is a decomposition process for a specific base vector system. Hence, the contravariant velocity components are decomposed components of velocity vector along the directions of coordinate lines, with respect to the covariant base vector system. However, the contravariant (and covariant) components are not physical quantities. Their magnitudes and dimensions are controlled by their corresponding covariant (and contravariant) base vectors.

Integral transformation solution of free-space cylindrical vector beams and prediction of modified Bessel-Gaussian vector beams.

PubMed

Li, Chun-Fang

2007-12-15

A unified description of free-space cylindrical vector beams is presented that is an integral transformation solution to the vector Helmholtz equation and the transversality condition. In the paraxial condition, this solution not only includes the known J(1) Bessel-Gaussian vector beam and the axisymmetric Laguerre-Gaussian vector beam that were obtained by solving the paraxial wave equations but also predicts two kinds of vector beam, called a modified Bessel-Gaussian vector beam.

RNAi in Arthropods: Insight into the Machinery and Applications for Understanding the Pathogen-Vector Interface

PubMed Central

Barnard, Annette-Christi; Nijhof, Ard M.; Fick, Wilma; Stutzer, Christian; Maritz-Olivier, Christine

2012-01-01

The availability of genome sequencing data in combination with knowledge of expressed genes via transcriptome and proteome data has greatly advanced our understanding of arthropod vectors of disease. Not only have we gained insight into vector biology, but also into their respective vector-pathogen interactions. By combining the strengths of postgenomic databases and reverse genetic approaches such as RNAi, the numbers of available drug and vaccine targets, as well as number of transgenes for subsequent transgenic or paratransgenic approaches, have expanded. These are now paving the way for in-field control strategies of vectors and their pathogens. Basic scientific questions, such as understanding the basic components of the vector RNAi machinery, is vital, as this allows for the transfer of basic RNAi machinery components into RNAi-deficient vectors, thereby expanding the genetic toolbox of these RNAi-deficient vectors and pathogens. In this review, we focus on the current knowledge of arthropod vector RNAi machinery and the impact of RNAi on understanding vector biology and vector-pathogen interactions for which vector genomic data is available on VectorBase. PMID:24705082

Optical implementation of inner product neural associative memory

NASA Technical Reports Server (NTRS)

Liu, Hua-Kuang (Inventor)

1995-01-01

An optical implementation of an inner-product neural associative memory is realized with a first spatial light modulator for entering an initial two-dimensional N-tuple vector and for entering a thresholded output vector image after each iteration until convergence is reached, and a second spatial light modulator for entering M weighted vectors of inner-product scalars multiplied with each of the M stored vectors, where the inner-product scalars are produced by multiplication of the initial input vector in the first iterative cycle (and thresholded vectors in subsequent iterative cycles) with each of the M stored vectors, and the weighted vectors are produced by multiplication of the scalars with corresponding ones of the stored vectors. A Hughes liquid crystal light valve is used for the dual function of summing the weighted vectors and thresholding the sum vector. The thresholded vector is then entered through the first spatial light modulator for reiteration of the process cycle until convergence is reached.

MODELO PARA EVALUACION DE DERRAMES DE HIDROCARBUROS (HSSM) GUIA DEL USUARIO

EPA Science Inventory

The U.S. Environmental Protection Agency is charged by Congress with protecting the Nation's land, air, and water resources. Under a mandate of national environmental laws, the Agency strives to formulate and implement actions leading to a compatible balance between human acti...

Dinámica de planetas extrasolares resonantes

NASA Astrophysics Data System (ADS)

Beauge, C.

Actualmente se han detectado 117 planetas alrededor de estrellas de Secuencia Principal, incluyendo 12 sistemas planetarios, cada uno con dos o tres miembros. De estos últimos, ocho poseen planetas en órbitas próximas y sus perturbaciones gravitacionales se convierten en un factor fundamental para la estabilidad orbital del sistema. Todos se encuentran en configuraciones resonantes, desde la conmensurabilidad de movimientos 2/1 de Gliese 876, hasta la resonancia secular de Ups And. En esta presentación analizamos varios aspectos de la dinámica resonante de los planetas extrasolares, incluyendo la existencia de soluciones de equilibrio, construcción de modelos analógicos y métodos para la determinación de masas individuales. También discutimos por qué las resonancias son tan frecuentes en estos sistemas, comparado con nuestro propio Sistema Solar. Por último, intentamos relacionar estos modelos con la hipótesis de migración planetaria, buscando límites en su extensión y en los posibles mecanismos que le dieron origen.

Vector nature of multi-soliton patterns in a passively mode-locked figure-eight fiber laser.

PubMed

Ning, Qiu-Yi; Liu, Hao; Zheng, Xu-Wu; Yu, Wei; Luo, Ai-Ping; Huang, Xu-Guang; Luo, Zhi-Chao; Xu, Wen-Cheng; Xu, Shan-Hui; Yang, Zhong-Min

2014-05-19

The vector nature of multi-soliton dynamic patterns was investigated in a passively mode-locked figure-eight fiber laser based on the nonlinear amplifying loop mirror (NALM). By properly adjusting the cavity parameters such as the pump power level and intra-cavity polarization controllers (PCs), in addition to the fundamental vector soliton, various vector multi-soliton regimes were observed, such as the random static distribution of vector multiple solitons, vector soliton cluster, vector soliton flow, and the state of vector multiple solitons occupying the whole cavity. Both the polarization-locked vector solitons (PLVSs) and the polarization-rotating vector solitons (PRVSs) were observed for fundamental soliton and each type of multi-soliton patterns. The obtained results further reveal the fundamental physics of multi-soliton patterns and demonstrate that the figure-eight fiber lasers are indeed a good platform for investigating the vector nature of different soliton types.

Efficient mouse airway transduction following recombination between AAV vectors carrying parts of a larger gene.

PubMed

Halbert, Christine L; Allen, James M; Miller, A Dusty

2002-07-01

The small packaging capacity of adeno-associated virus (AAV) vectors limits the utility of this promising vector system for transfer of large genes. We explored the possibility that larger genes could be reconstituted following homologous recombination between AAV vectors carrying overlapping gene fragments. An alkaline phosphatase (AP) gene was split between two such AAV vectors (rec vectors) and packaged using AAV2 or AAV6 capsid proteins. Rec vectors having either capsid protein recombined to express AP in cultured cells at about 1-2% of the rate observed for an intact vector. Surprisingly, the AAV6 rec vectors transduced lung cells in mice almost as efficiently as did an intact vector, with 10% of airway epithelial cells, the target for treatment of cystic fibrosis (CF), being positive. Thus AAV rec vectors may be useful for diseases such as CF that require transfer of large genes.

Method and system for operating an electric motor

DOEpatents

Gallegos-Lopez, Gabriel; Hiti, Silva; Perisic, Milun

2013-01-22

Methods and systems for operating an electric motor having a plurality of windings with an inverter having a plurality of switches coupled to a voltage source are provided. A first plurality of switching vectors is applied to the plurality of switches. The first plurality of switching vectors includes a first ratio of first magnitude switching vectors to second magnitude switching vectors. A direct current (DC) current associated with the voltage source is monitored during the applying of the first plurality of switching vectors to the plurality of switches. A second ratio of the first magnitude switching vectors to the second magnitude switching vectors is selected based on the monitoring of the DC current associated with the voltage source. A second plurality of switching vectors is applied to the plurality of switches. The second plurality of switching vectors includes the second ratio of the first magnitude switching vectors to the second magnitude switching vectors.

Syngeneic AAV pseudo-vectors potentiates full vector transduction

USDA-ARS?s Scientific Manuscript database

An excessive amount of empty capsids are generated during regular AAV vector production process. These pseudo-vectors often remain in final vectors used for animal studies or clinical trials. The potential effects of these pseudo-vectors on AAV transduction have been a major concern. In the current ...

Development of novel types of plastid transformation vectors and evaluation of factors controlling expression.

PubMed

Herz, Stefan; Füssl, Monika; Steiger, Sandra; Koop, Hans-Ulrich

2005-12-01

Two new vector types for plastid transformation were developed and uidA reporter gene expression was compared to standard transformation vectors. The first vector type does not contain any plastid promoter, instead it relies on extension of existing plastid operons and was therefore named "operon-extension" vector. When a strongly expressed plastid operon like psbA was extended by the reporter gene with this vector type, the expression level was superior to that of a standard vector under control of the 16S rRNA promoter. Different insertion sites, promoters and 5'-UTRs were analysed for their effect on reporter gene expression with standard and operon-extension vectors. The 5'-UTR of phage 7 gene 10 in combination with a modified N-terminus was found to yield the highest expression levels. Expression levels were also strongly dependent on external factors like plant or leaf age or light intensity. In the second vector type, named "split" plastid transformation vector, modules of the expression cassette were distributed on two separate vectors. Upon co-transformation of plastids with these vectors, the complete expression cassette became inserted into the plastome. This result can be explained by successive co-integration of the split vectors and final loop-out recombination of the duplicated sequences. The split vector concept was validated with different vector pairs.

The ecological foundations of transmission potential and vector-borne disease in urban landscapes.

PubMed

LaDeau, Shannon L; Allan, Brian F; Leisnham, Paul T; Levy, Michael Z

2015-07-01

Urban transmission of arthropod-vectored disease has increased in recent decades. Understanding and managing transmission potential in urban landscapes requires integration of sociological and ecological processes that regulate vector population dynamics, feeding behavior, and vector-pathogen interactions in these unique ecosystems. Vectorial capacity is a key metric for generating predictive understanding about transmission potential in systems with obligate vector transmission. This review evaluates how urban conditions, specifically habitat suitability and local temperature regimes, and the heterogeneity of urban landscapes can influence the biologically-relevant parameters that define vectorial capacity: vector density, survivorship, biting rate, extrinsic incubation period, and vector competence.Urban landscapes represent unique mosaics of habitat. Incidence of vector-borne disease in urban host populations is rarely, if ever, evenly distributed across an urban area. The persistence and quality of vector habitat can vary significantly across socio-economic boundaries to influence vector species composition and abundance, often generating socio-economically distinct gradients of transmission potential across neighborhoods.Urban regions often experience unique temperature regimes, broadly termed urban heat islands (UHI). Arthropod vectors are ectothermic organisms and their growth, survival, and behavior are highly sensitive to environmental temperatures. Vector response to UHI conditions is dependent on regional temperature profiles relative to the vector's thermal performance range. In temperate climates UHI can facilitate increased vector development rates while having countervailing influence on survival and feeding behavior. Understanding how urban heat island (UHI) conditions alter thermal and moisture constraints across the vector life cycle to influence transmission processes is an important direction for both empirical and modeling research.There remain persistent gaps in understanding of vital rates and drivers in mosquito-vectored disease systems, and vast holes in understanding for other arthropod vectored diseases. Empirical studies are needed to better understand the physiological constraints and socio-ecological processes that generate heterogeneity in critical transmission parameters, including vector survival and fitness. Likewise, laboratory experiments and transmission models must evaluate vector response to realistic field conditions, including variability in sociological and environmental conditions.

The role of remote sensing and GIS for spatial prediction of vector-borne diseases transmission: a systematic review.

PubMed

Palaniyandi, M

2012-12-01

There have been several attempts made to the appreciation of remote sensing and GIS for the study of vectors, biodiversity, vector presence, vector abundance and the vector-borne diseases with respect to space and time. This study was made for reviewing and appraising the potential use of remote sensing and GIS applications for spatial prediction of vector-borne diseases transmission. The nature of the presence and the abundance of vectors and vector-borne diseases, disease infection and the disease transmission are not ubiquitous and are confined with geographical, environmental and climatic factors, and are localized. The presence of vectors and vector-borne diseases is most complex in nature, however, it is confined and fueled by the geographical, climatic and environmental factors including man-made factors. The usefulness of the present day availability of the information derived from the satellite data including vegetation indices of canopy cover and its density, soil types, soil moisture, soil texture, soil depth, etc. is integrating the information in the expert GIS engine for the spatial analysis of other geoclimatic and geoenvironmental variables. The present study gives the detailed information on the classical studies of the past and present, and the future role of remote sensing and GIS for the vector-borne diseases control. The ecological modeling directly gives us the relevant information to understand the spatial variation of the vector biodiversity, vector presence, vector abundance and the vector-borne diseases in association with geoclimatic and the environmental variables. The probability map of the geographical distribution and seasonal variations of horizontal and vertical distribution of vector abundance and its association with vector -borne diseases can be obtained with low cost remote sensing and GIS tool with reliable data and speed.

A diagram for evaluating multiple aspects of model performance in simulating vector fields

NASA Astrophysics Data System (ADS)

Xu, Zhongfeng; Hou, Zhaolu; Han, Ying; Guo, Weidong

2016-12-01

Vector quantities, e.g., vector winds, play an extremely important role in climate systems. The energy and water exchanges between different regions are strongly dominated by wind, which in turn shapes the regional climate. Thus, how well climate models can simulate vector fields directly affects model performance in reproducing the nature of a regional climate. This paper devises a new diagram, termed the vector field evaluation (VFE) diagram, which is a generalized Taylor diagram and able to provide a concise evaluation of model performance in simulating vector fields. The diagram can measure how well two vector fields match each other in terms of three statistical variables, i.e., the vector similarity coefficient, root mean square length (RMSL), and root mean square vector difference (RMSVD). Similar to the Taylor diagram, the VFE diagram is especially useful for evaluating climate models. The pattern similarity of two vector fields is measured by a vector similarity coefficient (VSC) that is defined by the arithmetic mean of the inner product of normalized vector pairs. Examples are provided, showing that VSC can identify how close one vector field resembles another. Note that VSC can only describe the pattern similarity, and it does not reflect the systematic difference in the mean vector length between two vector fields. To measure the vector length, RMSL is included in the diagram. The third variable, RMSVD, is used to identify the magnitude of the overall difference between two vector fields. Examples show that the VFE diagram can clearly illustrate the extent to which the overall RMSVD is attributed to the systematic difference in RMSL and how much is due to the poor pattern similarity.

Thyra Abstract Interface Package

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bartlett, Roscoe A.

2005-09-01

Thrya primarily defines a set of abstract C++ class interfaces needed for the development of abstract numerical atgorithms (ANAs) such as iterative linear solvers, transient solvers all the way up to optimization. At the foundation of these interfaces are abstract C++ classes for vectors, vector spaces, linear operators and multi-vectors. Also included in the Thyra package is C++ code for creating concrete vector, vector space, linear operator, and multi-vector subclasses as well as other utilities to aid in the development of ANAs. Currently, very general and efficient concrete subclass implementations exist for serial and SPMD in-core vectors and multi-vectors. Codemore » also currently exists for testing objects and providing composite objects such as product vectors.« less

Vector 33: A reduce program for vector algebra and calculus in orthogonal curvilinear coordinates

NASA Astrophysics Data System (ADS)

Harper, David

1989-06-01

This paper describes a package with enables REDUCE 3.3 to perform algebra and calculus operations upon vectors. Basic algebraic operations between vectors and between scalars and vectors are provided, including scalar (dot) product and vector (cross) product. The vector differential operators curl, divergence, gradient and Laplacian are also defined, and are valid in any orthogonal curvilinear coordinate system. The package is written in RLISP to allow algebra and calculus to be performed using notation identical to that for operations. Scalars and vectors can be mixed quite freely in the same expression. The package will be of interest to mathematicians, engineers and scientists who need to perform vector calculations in orthogonal curvilinear coordinates.

Current Advances and Future Challenges in Adenoviral Vector Biology and Targeting

PubMed Central

Campos, Samuel K.; Barry, Michael A.

2008-01-01

Gene delivery vectors based on Adenoviral (Ad) vectors have enormous potential for the treatment of both hereditary and acquired disease. Detailed structural analysis of the Ad virion, combined with functional studies has broadened our knowledge of the structure/function relationships between Ad vectors and host cells/tissues and substantial achievement has been made towards a thorough understanding of the biology of Ad vectors. The widespread use of Ad vectors for clinical gene therapy is compromised by their inherent immunogenicity. The generation of safer and more effective Ad vectors, targeted to the site of disease, has therefore become a great ambition in the field of Ad vector development. This review provides a synopsis of the structure/function relationships between Ad vectors and host systems and summarizes the many innovative approaches towards achieving Ad vector targeting. PMID:17584037

Populações estelares do bojo galáctico

NASA Astrophysics Data System (ADS)

Escudero, A. V.; Costa, R. D. D.; Maciel, W. J.

2003-08-01

Os estudos mais recentes do bojo galáctico têm enfocado essencialmente as abundâncias químicas de elementos pesados, como o ferro, obtidos a partir das estrelas nas regiões centrais da galáxia. Elementos leves, como hélio, nitrogênio, oxigênio e argônio ainda são pouco estudados nestas regiões, devido à difícil determinação de suas abundâncias a partir de estrelas. Nestas condições as nebulosas planetárias desempenham um importante papel, pois permitem a determinação de abundâncias destes elementos usando técnicas de espectroscopia nebular. Neste trabalho, reportamos a análise das abundâncias químicas de uma nova amostra de nebulosas planetárias do bojo, bem como os resultados preliminares de um código numérico destinado a modelar a evolução química desta região. Usamos como vínculos observacionais os resultados obtidos das nebulosas planetárias, bem como de abundâncias estelares da região do bojo, obtidas da literatura. A partir deste modelo da evolução química e dos vínculos observacionais foi possível fazer um diagnóstico mais preciso das populações que constituem o bojo galáctico. O estudo destas populações que compõem a região central de nossa galáxia é de extrema importância para o maior entendimento da evolução química e dinâmica da galáxia como um todo. Por isto, verificamos a importância dos modelos de formação simples e mista utilizados para explicar características da população da região central da galáxia. Algumas destas características são: uma grande dispersão nos valores das abundâncias químicas e um grande espalhamento nas correlações entre as abundâcias de nitrogênio e oxigênio. Estas peculiaridades são dificilmente reproduzidas por modelos de formação simples, e portanto são importantes indícios da validade dos modelos de formação mista, tais como um rápido colapso do bojo seguido de uma evolução secular. (FAPESP, CNPq)

Elliptic-symmetry vector optical fields.

PubMed

Pan, Yue; Li, Yongnan; Li, Si-Min; Ren, Zhi-Cheng; Kong, Ling-Jun; Tu, Chenghou; Wang, Hui-Tian

2014-08-11

We present in principle and demonstrate experimentally a new kind of vector fields: elliptic-symmetry vector optical fields. This is a significant development in vector fields, as this breaks the cylindrical symmetry and enriches the family of vector fields. Due to the presence of an additional degrees of freedom, which is the interval between the foci in the elliptic coordinate system, the elliptic-symmetry vector fields are more flexible than the cylindrical vector fields for controlling the spatial structure of polarization and for engineering the focusing fields. The elliptic-symmetry vector fields can find many specific applications from optical trapping to optical machining and so on.

Kinematic sensitivity of robot manipulators

NASA Technical Reports Server (NTRS)

Vuskovic, Marko I.

1989-01-01

Kinematic sensitivity vectors and matrices for open-loop, n degrees-of-freedom manipulators are derived. First-order sensitivity vectors are defined as partial derivatives of the manipulator's position and orientation with respect to its geometrical parameters. The four-parameter kinematic model is considered, as well as the five-parameter model in case of nominally parallel joint axes. Sensitivity vectors are expressed in terms of coordinate axes of manipulator frames. Second-order sensitivity vectors, the partial derivatives of first-order sensitivity vectors, are also considered. It is shown that second-order sensitivity vectors can be expressed as vector products of the first-order sensitivity vectors.

Genetic variation in arthropod vectors of disease-causing organisms: obstacles and opportunities.

PubMed Central

Gooding, R H

1996-01-01

An overview of the genetic variation in arthropods that transmit pathogens to vertebrates is presented, emphasizing the genetics of vector-pathogen relationships and the biochemical genetics of vectors. Vector-pathogen interactions are reviewed briefly as a prelude to a discussion of the genetics of susceptibility and refractoriness in vectors. Susceptibility to pathogens is controlled by maternally inherited factors, sex-linked dominant alleles, and dominant and recessive autosomal genes. There is widespread interpopulation (including intercolony) and temporal variation in susceptibility to pathogens. The amount of biochemical genetic variation in vectors is similar to that found in other invertebrates. However, the amount varies widely among species, among populations within species, and temporally within populations. Biochemical genetic studies show that there is considerable genetic structuring of many vectors at the local, regional, and global levels. It is argued that genetic variation in vectors is critical in understanding vector-pathogen interactions and that genetic variation in vectors creates both obstacles to and opportunities for application of genetic techniques to the control of vectors. PMID:8809462

A Subdivision-Based Representation for Vector Image Editing.

PubMed

Liao, Zicheng; Hoppe, Hugues; Forsyth, David; Yu, Yizhou

2012-11-01

Vector graphics has been employed in a wide variety of applications due to its scalability and editability. Editability is a high priority for artists and designers who wish to produce vector-based graphical content with user interaction. In this paper, we introduce a new vector image representation based on piecewise smooth subdivision surfaces, which is a simple, unified and flexible framework that supports a variety of operations, including shape editing, color editing, image stylization, and vector image processing. These operations effectively create novel vector graphics by reusing and altering existing image vectorization results. Because image vectorization yields an abstraction of the original raster image, controlling the level of detail of this abstraction is highly desirable. To this end, we design a feature-oriented vector image pyramid that offers multiple levels of abstraction simultaneously. Our new vector image representation can be rasterized efficiently using GPU-accelerated subdivision. Experiments indicate that our vector image representation achieves high visual quality and better supports editing operations than existing representations.

Chromosomal integration of adenoviral vector DNA in vivo.

PubMed

Stephen, Sam Laurel; Montini, Eugenio; Sivanandam, Vijayshankar Ganesh; Al-Dhalimy, Muhseen; Kestler, Hans A; Finegold, Milton; Grompe, Markus; Kochanek, Stefan

2010-10-01

So far there has been no report of any clinical or preclinical evidence for chromosomal vector integration following adenovirus (Ad) vector-mediated gene transfer in vivo. We used liver gene transfer with high-capacity Ad vectors in the FAH(Deltaexon5) mouse model to analyze homologous and heterologous recombination events between vector and chromosomal DNA. Intravenous injection of Ad vectors either expressing a fumarylacetoacetate hydrolase (FAH) cDNA or carrying part of the FAH genomic locus resulted in liver nodules of FAH-expressing hepatocytes, demonstrating chromosomal vector integration. Analysis of junctions between vector and chromosomal DNA following heterologous recombination indicated integration of the vector genome through its termini. Heterologous recombination occurred with a median frequency of 6.72 x 10(-5) per transduced hepatocyte, while homologous recombination occurred more rarely with a median frequency of 3.88 x 10(-7). This study has established quantitative and qualitative data on recombination of adenoviral vector DNA with genomic DNA in vivo, contributing to a risk-benefit assessment of the biosafety of Ad vector-mediated gene transfer.

Adenoviral Vector Immunity: Its Implications and circumvention strategies

PubMed Central

Ahi, Yadvinder S.; Bangari, Dinesh S.; Mittal, Suresh K.

2014-01-01

Adenoviral (Ad) vectors have emerged as a promising gene delivery platform for a variety of therapeutic and vaccine purposes during last two decades. However, the presence of preexisting Ad immunity and the rapid development of Ad vector immunity still pose significant challenges to the clinical use of these vectors. Innate inflammatory response following Ad vector administration may lead to systemic toxicity, drastically limit vector transduction efficiency and significantly abbreviate the duration of transgene expression. Currently, a number of approaches are being extensively pursued to overcome these drawbacks by strategies that target either the host or the Ad vector. In addition, significant progress has been made in the development of novel Ad vectors based on less prevalent human Ad serotypes and nonhuman Ad. This review provides an update on our current understanding of immune responses to Ad vectors and delineates various approaches for eluding Ad vector immunity. Approaches targeting the host and those targeting the vector are discussed in light of their promises and limitations. PMID:21453277

Comparison of HIV- and EIAV-based vectors on their efficiency in transducing murine and human hematopoietic repopulating cells.

PubMed

Siapati, Elena K; Bigger, Brian W; Miskin, James; Chipchase, Daniel; Parsley, Kathryn L; Mitrophanous, Kyriacos; Themis, Mike; Thrasher, Adrian J; Bonnet, Dominique

2005-09-01

The use of lentiviral vectors for gene transfer into hematopoietic stem cells has raised considerable interest as these vectors can permanently integrate their genome into quiescent cells. Vectors based on alternative lentiviruses would theoretically be safer than HIV-1-based vectors and could also be used in HIV-positive patients, minimizing the risk of generating replication-competent virus. Here we report the use of third-generation equine infectious anemia virus (EIAV)- and HIV-1-based vectors with minimal viral sequences and absence of accessory proteins. We have compared their efficiency in transducing mouse and human hematopoietic stem cells both in vitro and in vivo to that of a previously documented second-generation HIV-1 vector. The third-generation EIAV- and HIV-based vectors gave comparable levels of transduction and transgene expression in both mouse and human NOD/SCID repopulating cells but were less efficient than the second-generation HIV-1 vector in human HSCs. For the EIAV vector this is possibly a reflection of the lower protein expression levels achieved in human cells, as vector copy number analysis revealed that this vector exhibited a trend to integrate equally efficiently compared to the third-generation HIV-1 vector in both mouse and human HSCs. Interestingly, the presence or absence of Tat in viral preparations did not influence the transduction efficiency of HIV-1 vectors in human HSCs.

Hexons from adenovirus serotypes 5 and 48 differentially protect adenovirus vectors from neutralization by mouse and human serum

PubMed Central

Harmon, Andrew W.; Moitra, Rituparna; Xu, Zhili

2018-01-01

Adenovirus vectors are widely used in gene therapy clinical trials, and preclinical studies with these vectors are often conducted in mice. It is therefore critical to understand whether mouse studies adequately predict the behavior of adenovirus vectors in humans. The most commonly-used adenovirus vectors are derived from adenovirus serotype 5 (Ad5). The Ad5 hexon protein can bind coagulation factor X (FX), and binding of FX has a major impact on vector interactions with other blood proteins. In mouse serum, FX protects Ad5 vectors from neutralization by natural antibodies and complement. In the current study, we similarly find that human FX inhibits neutralization of Ad5 vectors by human serum, and this finding is consistent among individual human sera. We show that human IgM and human IgG can each induce complement-mediated neutralization when Ad5 vectors are not protected by FX. Although mouse and human serum had similar effects on Ad5 vectors, we found that this was not true for a chimeric Ad5 vector that incorporated hexon regions from adenovirus serotype 48. Interestingly, this hexon-chimeric vector was neutralized by human serum, but not by mouse serum. These findings indicate that studies in mouse serum accurately predict the behavior of Ad5 vectors in human serum, but mouse serum is not an accurate model system for all adenovirus vectors. PMID:29401488

Iso-vector form factors of the delta and nucleon in QCD sum rules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ozpineci, A.

Form factors are important non-perturbative properties of hadrons. They give information about the internal structure of the hadrons. In this work, iso-vector axial-vector and iso-vector tensor form factors of the nucleon and the iso-vector axial-vector {Delta}{yields}N transition form factor calculations in QCD Sum Rules are presented.

Orthogonal vector algorithm to obtain the solar vector using the single-scattering Rayleigh model.

PubMed

Wang, Yinlong; Chu, Jinkui; Zhang, Ran; Shi, Chao

2018-02-01

Information obtained from a polarization pattern in the sky provides many animals like insects and birds with vital long-distance navigation cues. The solar vector can be derived from the polarization pattern using the single-scattering Rayleigh model. In this paper, an orthogonal vector algorithm, which utilizes the redundancy of the single-scattering Rayleigh model, is proposed. We use the intersection angles between the polarization vectors as the main criteria in our algorithm. The assumption that all polarization vectors can be considered coplanar is used to simplify the three-dimensional (3D) problem with respect to the polarization vectors in our simulation. The surface-normal vector of the plane, which is determined by the polarization vectors after translation, represents the solar vector. Unfortunately, the two-directionality of the polarization vectors makes the resulting solar vector ambiguous. One important result of this study is, however, that this apparent disadvantage has no effect on the complexity of the algorithm. Furthermore, two other universal least-squares algorithms were investigated and compared. A device was then constructed, which consists of five polarized-light sensors as well as a 3D attitude sensor. Both the simulation and experimental data indicate that the orthogonal vector algorithms, if used with a suitable threshold, perform equally well or better than the other two algorithms. Our experimental data reveal that if the intersection angles between the polarization vectors are close to 90°, the solar-vector angle deviations are small. The data also support the assumption of coplanarity. During the 51 min experiment, the mean of the measured solar-vector angle deviations was about 0.242°, as predicted by our theoretical model.

Insulated Foamy Viral Vectors

PubMed Central

Browning, Diana L.; Collins, Casey P.; Hocum, Jonah D.; Leap, David J.; Rae, Dustin T.; Trobridge, Grant D.

2016-01-01

Retroviral vector-mediated gene therapy is promising, but genotoxicity has limited its use in the clinic. Genotoxicity is highly dependent on the retroviral vector used, and foamy viral (FV) vectors appear relatively safe. However, internal promoters may still potentially activate nearby genes. We developed insulated FV vectors, using four previously described insulators: a version of the well-studied chicken hypersensitivity site 4 insulator (650cHS4), two synthetic CCCTC-binding factor (CTCF)-based insulators, and an insulator based on the CCAAT box-binding transcription factor/nuclear factor I (7xCTF/NF1). We directly compared these insulators for enhancer-blocking activity, effect on FV vector titer, and fidelity of transfer to both proviral long terminal repeats. The synthetic CTCF-based insulators had the strongest insulating activity, but reduced titers significantly. The 7xCTF/NF1 insulator did not reduce titers but had weak insulating activity. The 650cHS4-insulated FV vector was identified as the overall most promising vector. Uninsulated and 650cHS4-insulated FV vectors were both significantly less genotoxic than gammaretroviral vectors. Integration sites were evaluated in cord blood CD34+ cells and the 650cHS4-insulated FV vector had fewer hotspots compared with an uninsulated FV vector. These data suggest that insulated FV vectors are promising for hematopoietic stem cell gene therapy. PMID:26715244

Construction and Evaluation of Novel Rhesus Monkey Adenovirus Vaccine Vectors

PubMed Central

Abbink, Peter; Maxfield, Lori F.; Ng'ang'a, David; Borducchi, Erica N.; Iampietro, M. Justin; Bricault, Christine A.; Teigler, Jeffrey E.; Blackmore, Stephen; Parenteau, Lily; Wagh, Kshitij; Handley, Scott A.; Zhao, Guoyan; Virgin, Herbert W.; Korber, Bette

2014-01-01

ABSTRACT Adenovirus vectors are widely used as vaccine candidates for a variety of pathogens, including HIV-1. To date, human and chimpanzee adenoviruses have been explored in detail as vaccine vectors. The phylogeny of human and chimpanzee adenoviruses is overlapping, and preexisting humoral and cellular immunity to both are exhibited in human populations worldwide. More distantly related adenoviruses may therefore offer advantages as vaccine vectors. Here we describe the primary isolation and vectorization of three novel adenoviruses from rhesus monkeys. The seroprevalence of these novel rhesus monkey adenovirus vectors was extremely low in sub-Saharan Africa human populations, and these vectors proved to have immunogenicity comparable to that of human and chimpanzee adenovirus vaccine vectors in mice. These rhesus monkey adenoviruses phylogenetically clustered with the poorly described adenovirus species G and robustly stimulated innate immune responses. These novel adenoviruses represent a new class of candidate vaccine vectors. IMPORTANCE Although there have been substantial efforts in the development of vaccine vectors from human and chimpanzee adenoviruses, far less is known about rhesus monkey adenoviruses. In this report, we describe the isolation and vectorization of three novel rhesus monkey adenoviruses. These vectors exhibit virologic and immunologic characteristics that make them attractive as potential candidate vaccine vectors for both HIV-1 and other pathogens. PMID:25410856

Construction and evaluation of novel rhesus monkey adenovirus vaccine vectors.

PubMed

Abbink, Peter; Maxfield, Lori F; Ng'ang'a, David; Borducchi, Erica N; Iampietro, M Justin; Bricault, Christine A; Teigler, Jeffrey E; Blackmore, Stephen; Parenteau, Lily; Wagh, Kshitij; Handley, Scott A; Zhao, Guoyan; Virgin, Herbert W; Korber, Bette; Barouch, Dan H

2015-02-01

Adenovirus vectors are widely used as vaccine candidates for a variety of pathogens, including HIV-1. To date, human and chimpanzee adenoviruses have been explored in detail as vaccine vectors. The phylogeny of human and chimpanzee adenoviruses is overlapping, and preexisting humoral and cellular immunity to both are exhibited in human populations worldwide. More distantly related adenoviruses may therefore offer advantages as vaccine vectors. Here we describe the primary isolation and vectorization of three novel adenoviruses from rhesus monkeys. The seroprevalence of these novel rhesus monkey adenovirus vectors was extremely low in sub-Saharan Africa human populations, and these vectors proved to have immunogenicity comparable to that of human and chimpanzee adenovirus vaccine vectors in mice. These rhesus monkey adenoviruses phylogenetically clustered with the poorly described adenovirus species G and robustly stimulated innate immune responses. These novel adenoviruses represent a new class of candidate vaccine vectors. Although there have been substantial efforts in the development of vaccine vectors from human and chimpanzee adenoviruses, far less is known about rhesus monkey adenoviruses. In this report, we describe the isolation and vectorization of three novel rhesus monkey adenoviruses. These vectors exhibit virologic and immunologic characteristics that make them attractive as potential candidate vaccine vectors for both HIV-1 and other pathogens. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Vector Addition: Effect of the Context and Position of the Vectors

NASA Astrophysics Data System (ADS)

Barniol, Pablo; Zavala, Genaro

2010-10-01

In this article we investigate the effect of: 1) the context, and 2) the position of the vectors, on 2D vector addition tasks. We administered a test to 512 students completing introductory physics courses at a private Mexican university. In the first part, we analyze students' responses in three isomorphic problems: displacements, forces, and no physical context. Students were asked to draw two vectors and the vector sum. We analyzed students' procedures detecting the difficulties when drawing the vector addition and proved that the context matters, not only compared to the context-free case but also between the contexts. In the second part, we analyze students' responses with three different arrangements of the sum of two vectors: tail-to-tail, head-to-tail and separated vectors. We compared the frequencies of the errors in the three different positions to deduce students' conceptions in the addition of vectors.

Vectors and Rotations in 3-Dimensions: Vector Algebra for the C++ Programmer

DTIC Science & Technology

2016-12-01

Proving Ground, MD 21005-5068 This report describes 2 C++ classes: a Vector class for performing vector algebra in 3-dimensional space ( 3D ) and a Rotation...class for performing rotations of vectors in 3D . Each class is self-contained in a single header file (Vector.h and Rotation.h) so that a C...vector, rotation, 3D , quaternion, C++ tools, rotation sequence, Euler angles, yaw, pitch, roll, orientation 98 Richard Saucier 410-278-6721Unclassified

Effects of internal yaw-vectoring devices on the static performance of a pitch-vectoring nonaxisymmetric convergent-divergent nozzle

NASA Technical Reports Server (NTRS)

Asbury, Scott C.

1993-01-01

An investigation was conducted in the static test facility of the Langley 16-Foot Transonic Tunnel to evaluate the internal performance of a nonaxisymmetric convergent divergent nozzle designed to have simultaneous pitch and yaw thrust vectoring capability. This concept utilized divergent flap deflection for thrust vectoring in the pitch plane and flow-turning deflectors installed within the divergent flaps for yaw thrust vectoring. Modifications consisting of reducing the sidewall length and deflecting the sidewall outboard were investigated as means to increase yaw-vectoring performance. This investigation studied the effects of multiaxis (pitch and yaw) thrust vectoring on nozzle internal performance characteristics. All tests were conducted with no external flow, and nozzle pressure ratio was varied from 2.0 to approximately 13.0. The results indicate that this nozzle concept can successfully generate multiaxis thrust vectoring. Deflection of the divergent flaps produced resultant pitch vector angles that, although dependent on nozzle pressure ratio, were nearly equal to the geometric pitch vector angle. Losses in resultant thrust due to pitch vectoring were small or negligible. The yaw deflectors produced resultant yaw vector angles up to 21 degrees that were controllable by varying yaw deflector rotation. However, yaw deflector rotation resulted in significant losses in thrust ratios and, in some cases, nozzle discharge coefficient. Either of the sidewall modifications generally reduced these losses and increased maximum resultant yaw vector angle. During multiaxis (simultaneous pitch and yaw) thrust vectoring, little or no cross coupling between the thrust vectoring processes was observed.

VectorBase: a data resource for invertebrate vector genomics

PubMed Central

Lawson, Daniel; Arensburger, Peter; Atkinson, Peter; Besansky, Nora J.; Bruggner, Robert V.; Butler, Ryan; Campbell, Kathryn S.; Christophides, George K.; Christley, Scott; Dialynas, Emmanuel; Hammond, Martin; Hill, Catherine A.; Konopinski, Nathan; Lobo, Neil F.; MacCallum, Robert M.; Madey, Greg; Megy, Karine; Meyer, Jason; Redmond, Seth; Severson, David W.; Stinson, Eric O.; Topalis, Pantelis; Birney, Ewan; Gelbart, William M.; Kafatos, Fotis C.; Louis, Christos; Collins, Frank H.

2009-01-01

VectorBase (http://www.vectorbase.org) is an NIAID-funded Bioinformatic Resource Center focused on invertebrate vectors of human pathogens. VectorBase annotates and curates vector genomes providing a web accessible integrated resource for the research community. Currently, VectorBase contains genome information for three mosquito species: Aedes aegypti, Anopheles gambiae and Culex quinquefasciatus, a body louse Pediculus humanus and a tick species Ixodes scapularis. Since our last report VectorBase has initiated a community annotation system, a microarray and gene expression repository and controlled vocabularies for anatomy and insecticide resistance. We have continued to develop both the software infrastructure and tools for interrogating the stored data. PMID:19028744

Production, concentration and titration of pseudotyped HIV-1-based lentiviral vectors.

PubMed

Kutner, Robert H; Zhang, Xian-Yang; Reiser, Jakob

2009-01-01

Over the past decade, lentiviral vectors have emerged as powerful tools for transgene delivery. The use of lentiviral vectors has become commonplace and applications in the fields of neuroscience, hematology, developmental biology, stem cell biology and transgenesis are rapidly emerging. Also, lentiviral vectors are at present being explored in the context of human clinical trials. Here we describe improved protocols to generate highly concentrated lentiviral vector pseudotypes involving different envelope glycoproteins. In this protocol, vector stocks are prepared by transient transfection using standard cell culture media or serum-free media. Such stocks are then concentrated by ultracentrifugation and/or ion exchange chromatography, or by precipitation using polyethylene glycol 6000, resulting in vector titers of up to 10(10) transducing units per milliliter and above. We also provide reliable real-time PCR protocols to titrate lentiviral vectors based on proviral DNA copies present in genomic DNA extracted from transduced cells or on vector RNA. These production/concentration methods result in high-titer vector preparations that show reduced toxicity compared with lentiviral vectors produced using standard protocols involving ultracentrifugation-based methods. The vector production and titration protocol described here can be completed within 8 d.

Helper-Free Foamy Virus Vectors

PubMed Central

TROBRIDGE, GRANT D.; RUSSELL, DAVID W.

2010-01-01

Retroviral vectors based on human foamy virus (HFV) have been developed and show promise as gene therapy vehicles. Here we describe a method for the production of HFV vector stocks free of detectable helper virus. The helper and vector plasmid constructs used both lack the HFV bel genes, so recombination between these constructs cannot create a wild-type virus. A fusion promoter that combines portions of the cytomegalovirus (CMV) immediate-early and HFV long terminal repeat (LTR) promoters was used to drive expression of both the helper and vector constructs. The CMV–LTR fusion promoter allows for HFV vector production in the absence of the Bel-1 trans-activator protein, which would otherwise be necessary for efficient transcription from the HFV LTR. Vector stocks containing either neomycin phosphotransferase or alkaline phosphatase reporter genes were produced by transient transfection at titers greater than 105 transducing units/ml. G418-resistant BHK-21 cells obtained by transduction with neo vectors contained randomly integrated HFV vector proviruses without detectable deletions or rearrangements. The vector stocks generated were free of replication-competent retrovirus (RCR), as determined by assays for LTR trans-activation and a marker rescue assay developed here for the detection of Bel-independent RCR. OVERVIEW SUMMARY Vectors based on human foamy virus have been developed but low titers and the presence of replication-competent retrovirus (RCR) in vector stocks have prevented their use in preclinical animal experiments. We have developed a transient transfection method that can be used to produce replication-incompetent HFV vector stocks at titers greater than 105/ml, and that does not produce contaminating RCR. The use of CMV-HFV LTR fusion promoters in the helper and vector constructs has circumvented the requirement for the HFV Bel-1 trans-activator protein. Consequently, the potential for generating wild-type HFV by recombination between helper and vector constructs during vector production has been eliminated. Here we describe HFV vector production using this Bel-independent system. PMID:9853518

Repeat Transduction in the Mouse Lung by Using Adeno-Associated Virus Vectors with Different Serotypes

PubMed Central

Halbert, Christine L.; Rutledge, Elizabeth A.; Allen, James M.; Russell, David W.; Miller, A. Dusty

2000-01-01

Vectors derived from adeno-associated virus type 2 (AAV2) promote gene transfer and expression in the lung; however, we have found that while gene expression can persist for at least 8 months in mice, it was reduced dramatically in rabbits over a period of 2 months. The efficiency and persistence of AAV2-mediated gene expression in the human lung have yet to be determined, but it seems likely that readministration will be necessary over the lifetime of an individual. Unfortunately, we have found that transduction by a second administration of an AAV2 vector is blocked, presumably due to neutralizing antibodies generated in response to the primary vector exposure. Here, we have explored the use of AAV2 vectors pseudotyped with capsid proteins from AAV serotypes 2, 3, and 6 for readministration in the mouse lung. We found that an AAV6 vector transduced airway epithelial and alveolar cells in the lung at rates that were at least as high as those of AAV2 pseudotype vectors, while transduction rates mediated by AAV3 were much lower. AAV6 pseudotype vector transduction was unaffected by prior administration of an AAV2 or AAV3 vector, and transduction by an AAV2 pseudotype vector was unaffected by prior AAV6 vector administration, showing that cross-reactive neutralizing antibodies against AAV2 and AAV6 are not generated in mice. Interestingly, while prior administration of an AAV2 vector completely blocked transduction by a second AAV2 pseudotype vector, prior administration of an AAV6 vector only partially inhibited transduction by a second administration of an AAV6 pseudotype vector. Analysis of sera obtained from mice and humans showed that AAV6 is less immunogenic than AAV2, which helps explain this finding. These results support the development of AAV6 vectors for lung gene therapy both alone and in combination with AAV2 vectors. PMID:10627564

Cómo calcular el índice UV

EPA Pesticide Factsheets

Información sobre cómo calcular el Índice ultravioleta (UV) a través de un modelo numérico que relaciona la intensidad de la radiación solar ultra violeta (UV) en la superficie terrestre con la concentración pronosticada de ozono estratosférico.

The effects of noise due to random undetected tilts and paleosecular variation on regional paleomagnetic directions

USGS Publications Warehouse

Calderone, G.J.; Butler, R.F.

1991-01-01

Random tilting of a single paleomagnetic vector produces a distribution of vectors which is not rotationally symmetric about the original vector and therefore not Fisherian. Monte Carlo simulations were performed on two types of vector distributions: 1) distributions of vectors formed by perturbing a single original vector with a Fisher distribution of bedding poles (each defining a tilt correction) and 2) standard Fisher distributions. These simulations demonstrate that inclinations of vectors drawn from both distributions are biased toward shallow inclinations. The Fisher mean direction of the distribution of vectors formed by perturbing a single vector with random undetected tilts is biased toward shallow inclinations, but this bias is insignificant for angular dispersions of bedding poles less than 20??. -from Authors

Fuzzy model to estimate the number of hospitalizations for asthma and pneumonia under the effects of air pollution.

PubMed

Chaves, Luciano Eustáquio; Nascimento, Luiz Fernando Costa; Rizol, Paloma Maria Silva Rocha

2017-06-22

Predict the number of hospitalizations for asthma and pneumonia associated with exposure to air pollutants in the city of São José dos Campos, São Paulo State. This is a computational model using fuzzy logic based on Mamdani's inference method. For the fuzzification of the input variables of particulate matter, ozone, sulfur dioxide and apparent temperature, we considered two relevancy functions for each variable with the linguistic approach: good and bad. For the output variable number of hospitalizations for asthma and pneumonia, we considered five relevancy functions: very low, low, medium, high and very high. DATASUS was our source for the number of hospitalizations in the year 2007 and the result provided by the model was correlated with the actual data of hospitalization with lag from zero to two days. The accuracy of the model was estimated by the ROC curve for each pollutant and in those lags. In the year of 2007, 1,710 hospitalizations by pneumonia and asthma were recorded in São José dos Campos, State of São Paulo, with a daily average of 4.9 hospitalizations (SD = 2.9). The model output data showed positive and significant correlation (r = 0.38) with the actual data; the accuracies evaluated for the model were higher for sulfur dioxide in lag 0 and 2 and for particulate matter in lag 1. Fuzzy modeling proved accurate for the pollutant exposure effects and hospitalization for pneumonia and asthma approach. Prever o número de internações por asma e pneumonia associadas à exposição a poluentes do ar no município em São José dos Campos, estado de São Paulo. Trata-se de um modelo computacional que utiliza a lógica fuzzy baseado na técnica de inferência de Mamdani. Para a fuzzificação das variáveis de entrada material particulado, ozônio, dióxido de enxofre e temperatura aparente foram consideradas duas funções de pertinência para cada variável com abordagem linguísticas: bom e ruim. Para a variável de saída número internações por asma e pneumonia, foram consideradas cinco funções de pertinências: muito baixo, baixo, médio, alto e muito alto. O número de internações no ano de 2007 foi obtido do Datasus e o resultado fornecido pelo modelo foi correlacionado com os dados reais de internação com defasagem (lag) de zero a dois dias. A acurácia do modelo foi estimada pela curva ROC para cada poluente e nestas defasagens. No ano de 2007 foram registradas 1.710 internações por pneumonia e asma em São José dos Campos, SP, com média diária de 4,9 internações (dp = 2,9). Os dados de saída do modelo mostraram correlação positiva e significativa (r = 0,38) com os dados reais; as acurácias avaliadas para o modelo foram maiores para o dióxido de enxofre nos lag 0 e 2 e para o material particulado no lag 1. Modelagem fuzzy se mostrou acurada para a abordagem de efeitos da exposição aos poluentes e internação por pneumonia e asma.

Study and optimization of the macroscopic electrical response of carbon based nanocomposites for advanced applications

NASA Astrophysics Data System (ADS)

Silva, Jaime Pedro Oliveira da

A presente tese centrou-se no estudo da resposta da constante dieletrica e condutividade eletrica em materiais compositos nos quais o reforco tinha uma elevada proporcao entre comprimento e diametro. O objeto de estudo foi o efeito de um reforco com uma elevada razao entre comprimento e diametro, concentracao e orientacao na resposta eletrica e dieletrica de um composito. Estes compositos tem uma grande importancia no desenvolvimento de materiais para sensores e atuadores. Num primeiro momento da dissertacao, explorou-se a resposta da constante dieletrica de um composito constituido por nanotubos de carbono como reforco e uma matriz polimerica. Verificou-se que um aumento da razao entre comprimento e diametro do reforco tem o efeito de aumentar a constante dieletrica do composito para uma igual fracao volumetrica de reforco. Constatou-se tambem que materiais na fase nematica demonstram uma constante dieletrica mais baixa quando comparados com materiais onde o reforco esta distribuido aleatoriamente. Ficou ainda demonstrado nesta dissertacao que materiais na fase nematica com razoes entre o comprimento e diametro diferentes a constante dieletrica segue uma lei de potencia. Numa segunda fase do trabalho, foi explorada a condutividade de nanocompositos polimericos reforcados com nanotubos de carbono, atraves de um modelo baseado em cilindros impenetraveis. Ficou demonstrado que o modelo e apropriado para descrever a condutividade eletrica de um nanocomposito polimerico reforcado com nanotubos. As simulacoes desenvolvidas demonstram que, aumentando a razao entre o comprimento e o diametro dos nanotubos de carbono, aumenta a condutividade eletrica do nanocomposito. No entanto, verifica-se que aumentando a anisotropia diminui a condutividade, sendo este efeito mais evidente para fracoes volumetricas maiores. Nesta dissertacao comprovou-se ainda que uma microestrutura gerada por um algoritmo de empacotamento sequencial pode ser descrita por um grafo aleatorio e que a condutividade num composito reforcado com nanofibras de carbono pode ser descrito por uma rede de Bethe. Atraves do uso da teoria das redes complexas, chegou-se a uma expressao para o limite de percolacao e, do mesmo modo, demonstrou-se que “hopping” entre fibras adjacentes resulta numa expressao que corresponde a um regime de desordem fraca. No trabalho desenvolvido tambem foi calculado os expoentes criticos, atraves da teoria das redes, para um sistema 3D composto por cilindros impenetraveis com uma interacao de curto alcance, demonstrando que os expoentes criticos estao relacionados por uma relacao de hiperescala comum para 3D e nao pertencem a mesma classe de universalidade como a percolacao numa rede. A aplicacao do modelo desenvolvido a compositos de epoxy reforcada, com diferentes metodos de dispersao de nanofibras de carbono, revelou que os metodos de dispersao usados para preparar os compositos tem uma forte influencia nas propriedades eletricas que podem ser capturadas pelo modelo. Neste contexto, ficou ainda demonstrado que a condutividade eletrica pode ser descrita por um regime de desordem fraca, isto ´e, um regime onde todas as conexoes fibra-fibra participam na condutividade do composito. O modelo desenvolvido foi aplicado igualmente a compositos de poly (vinylidene fluoride) reforcado com nanotubos de carbono com diferentes tratamentos de termicos de oxidacao. Verificou-se que os tratamentos de superficie aumentam o limite de percolacao e diminuem a condutividade. Nesta dissertacao provamos ainda que a condutividade do composito pode ser atribuida a um mecanismo de “hopping”, fortemente afetado pelos tratamentos de superficie dos reforcos.

The application of vector concepts on two skew lines

NASA Astrophysics Data System (ADS)

Alghadari, F.; Turmudi; Herman, T.

2018-01-01

The purpose of this study is knowing how to apply vector concepts on two skew lines in three-dimensional (3D) coordinate and its utilization. Several mathematical concepts have a related function for the other, but the related between the concept of vector and 3D have not applied in learning classroom. In fact, there are studies show that female students have difficulties in learning of 3D than male. It is because of personal spatial intelligence. The relevance of vector concepts creates both learning achievement and mathematical ability of male and female students enables to be balanced. The distance like on a cube, cuboid, or pyramid whose are drawn on the rectangular coordinates of a point in space. Two coordinate points of the lines can be created a vector. The vector of two skew lines has the shortest distance and the angle. Calculating of the shortest distance is started to create two vectors as a representation of line by vector position concept, next to determining a norm-vector of two vector which was obtained by cross-product, and then to create a vector from two combination of pair-points which was passed by two skew line, the shortest distance is scalar orthogonal projection of norm-vector on a vector which is a combination of pair-points. While calculating the angle are used two vectors as a representation of line to dot-product, and the inverse of cosine is yield. The utilization of its application on mathematics learning and orthographic projection method.

Unique Safety Issues Associated with Virus Vectored Vaccines: Potential for and Theoretical Consequences of Recombination with Wild Type Virus Strains

PubMed Central

Condit, Richard C.; Williamson, Anna-Lise; Sheets, Rebecca; Seligman, Stephen J.; Monath, Thomas P.; Excler, Jean-Louis; Gurwith, Marc; Bok, Karin; Robertson, James S.; Kim, Denny; Hendry, Michael; Singh, Vidisha; Mac, Lisa M.; Chen, Robert T.

2016-01-01

In 2003 and 2013, the World Health Organization convened informal consultations on characterization and quality aspects of vaccines based on live virus vectors. In the resulting reports, one of several issues raised for future study was the potential for recombination of virus-vectored vaccines with wild type pathogenic virus strains. This paper presents an assessment of this issue formulated by the Brighton Collaboration. To provide an appropriate context for understanding the potential for recombination of virus-vectored vaccines, we review briefly the current status of virus vectored vaccines, mechanisms of recombination between viruses, experience with recombination involving live attenuated vaccines in the field, and concerns raised previously in the literature regarding recombination of virus-vectored vaccines with wild type virus strains. We then present a discussion of the major variables that could influence recombination between a virus-vectored vaccine and circulating wild type virus and the consequences of such recombination, including intrinsic recombination properties of the parent virus used as a vector; sequence relatedness of vector and wild virus; virus host range, pathogenesis and transmission; replication competency of vector in target host; mechanism of vector attenuation; additional factors potentially affecting virulence; and circulation of multiple recombinant vectors in the same target population. Finally, we present some guiding principles for vector design and testing intended to anticipate and mitigate the potential for and consequences of recombination of virus-vectored vaccines with wild type pathogenic virus strains. PMID:27346303

The assisted prediction modelling frame with hybridisation and ensemble for business risk forecasting and an implementation

NASA Astrophysics Data System (ADS)

Li, Hui; Hong, Lu-Yao; Zhou, Qing; Yu, Hai-Jie

2015-08-01

The business failure of numerous companies results in financial crises. The high social costs associated with such crises have made people to search for effective tools for business risk prediction, among which, support vector machine is very effective. Several modelling means, including single-technique modelling, hybrid modelling, and ensemble modelling, have been suggested in forecasting business risk with support vector machine. However, existing literature seldom focuses on the general modelling frame for business risk prediction, and seldom investigates performance differences among different modelling means. We reviewed researches on forecasting business risk with support vector machine, proposed the general assisted prediction modelling frame with hybridisation and ensemble (APMF-WHAE), and finally, investigated the use of principal components analysis, support vector machine, random sampling, and group decision, under the general frame in forecasting business risk. Under the APMF-WHAE frame with support vector machine as the base predictive model, four specific predictive models were produced, namely, pure support vector machine, a hybrid support vector machine involved with principal components analysis, a support vector machine ensemble involved with random sampling and group decision, and an ensemble of hybrid support vector machine using group decision to integrate various hybrid support vector machines on variables produced from principle components analysis and samples from random sampling. The experimental results indicate that hybrid support vector machine and ensemble of hybrid support vector machines were able to produce dominating performance than pure support vector machine and support vector machine ensemble.

Learning with LOGO: Logo and Vectors.

ERIC Educational Resources Information Center

Lough, Tom; Tipps, Steve

1986-01-01

This is the first of a two-part series on the general concept of vector space. Provides tool procedures to allow investigation of vector properties, vector addition and subtraction, and X and Y components. Lists several sources of additional vector ideas. (JM)

The Design of a Templated C++ Small Vector Class for Numerical Computing

NASA Technical Reports Server (NTRS)

Moran, Patrick J.

2000-01-01

We describe the design and implementation of a templated C++ class for vectors. The vector class is templated both for vector length and vector component type; the vector length is fixed at template instantiation time. The vector implementation is such that for a vector of N components of type T, the total number of bytes required by the vector is equal to N * size of (T), where size of is the built-in C operator. The property of having a size no bigger than that required by the components themselves is key in many numerical computing applications, where one may allocate very large arrays of small, fixed-length vectors. In addition to the design trade-offs motivating our fixed-length vector design choice, we review some of the C++ template features essential to an efficient, succinct implementation. In particular, we highlight some of the standard C++ features, such as partial template specialization, that are not supported by all compilers currently. This report provides an inventory listing the relevant support currently provided by some key compilers, as well as test code one can use to verify compiler capabilities.

The quest for a non-vector psyllid: Natural variation in acquisition and transmission of the huanglongbing pathogen 'Candidatus Liberibacter asiaticus' by Asian citrus psyllid isofemale lines

USDA-ARS?s Scientific Manuscript database

Genetic variability in insect vectors is valuable to study vector competence determinants and to select non-vector populations that may help reduce the spread of vector-borne pathogens. We collected and tested vector competency of 15 isofemale lines of Asian citrus psyllid (ACP) Diaphorina citri, v...

All That Glisters Is Not Gold: Sampling-Process Uncertainty in Disease-Vector Surveys with False-Negative and False-Positive Detections

PubMed Central

Abad-Franch, Fernando; Valença-Barbosa, Carolina; Sarquis, Otília; Lima, Marli M.

2014-01-01

Background Vector-borne diseases are major public health concerns worldwide. For many of them, vector control is still key to primary prevention, with control actions planned and evaluated using vector occurrence records. Yet vectors can be difficult to detect, and vector occurrence indices will be biased whenever spurious detection/non-detection records arise during surveys. Here, we investigate the process of Chagas disease vector detection, assessing the performance of the surveillance method used in most control programs – active triatomine-bug searches by trained health agents. Methodology/Principal Findings Control agents conducted triplicate vector searches in 414 man-made ecotopes of two rural localities. Ecotope-specific ‘detection histories’ (vectors or their traces detected or not in each individual search) were analyzed using ordinary methods that disregard detection failures and multiple detection-state site-occupancy models that accommodate false-negative and false-positive detections. Mean (±SE) vector-search sensitivity was ∼0.283±0.057. Vector-detection odds increased as bug colonies grew denser, and were lower in houses than in most peridomestic structures, particularly woodpiles. False-positive detections (non-vector fecal streaks misidentified as signs of vector presence) occurred with probability ∼0.011±0.008. The model-averaged estimate of infestation (44.5±6.4%) was ∼2.4–3.9 times higher than naïve indices computed assuming perfect detection after single vector searches (11.4–18.8%); about 106–137 infestation foci went undetected during such standard searches. Conclusions/Significance We illustrate a relatively straightforward approach to addressing vector detection uncertainty under realistic field survey conditions. Standard vector searches had low sensitivity except in certain singular circumstances. Our findings suggest that many infestation foci may go undetected during routine surveys, especially when vector density is low. Undetected foci can cause control failures and induce bias in entomological indices; this may confound disease risk assessment and mislead program managers into flawed decision making. By helping correct bias in naïve indices, the approach we illustrate has potential to critically strengthen vector-borne disease control-surveillance systems. PMID:25233352

Balancing aggregation and smoothing errors in inverse models

DOE PAGES

Turner, A. J.; Jacob, D. J.

2015-06-30

Inverse models use observations of a system (observation vector) to quantify the variables driving that system (state vector) by statistical optimization. When the observation vector is large, such as with satellite data, selecting a suitable dimension for the state vector is a challenge. A state vector that is too large cannot be effectively constrained by the observations, leading to smoothing error. However, reducing the dimension of the state vector leads to aggregation error as prior relationships between state vector elements are imposed rather than optimized. Here we present a method for quantifying aggregation and smoothing errors as a function ofmore » state vector dimension, so that a suitable dimension can be selected by minimizing the combined error. Reducing the state vector within the aggregation error constraints can have the added advantage of enabling analytical solution to the inverse problem with full error characterization. We compare three methods for reducing the dimension of the state vector from its native resolution: (1) merging adjacent elements (grid coarsening), (2) clustering with principal component analysis (PCA), and (3) applying a Gaussian mixture model (GMM) with Gaussian pdfs as state vector elements on which the native-resolution state vector elements are projected using radial basis functions (RBFs). The GMM method leads to somewhat lower aggregation error than the other methods, but more importantly it retains resolution of major local features in the state vector while smoothing weak and broad features.« less

Balancing aggregation and smoothing errors in inverse models

NASA Astrophysics Data System (ADS)

Turner, A. J.; Jacob, D. J.

2015-01-01

Inverse models use observations of a system (observation vector) to quantify the variables driving that system (state vector) by statistical optimization. When the observation vector is large, such as with satellite data, selecting a suitable dimension for the state vector is a challenge. A state vector that is too large cannot be effectively constrained by the observations, leading to smoothing error. However, reducing the dimension of the state vector leads to aggregation error as prior relationships between state vector elements are imposed rather than optimized. Here we present a method for quantifying aggregation and smoothing errors as a function of state vector dimension, so that a suitable dimension can be selected by minimizing the combined error. Reducing the state vector within the aggregation error constraints can have the added advantage of enabling analytical solution to the inverse problem with full error characterization. We compare three methods for reducing the dimension of the state vector from its native resolution: (1) merging adjacent elements (grid coarsening), (2) clustering with principal component analysis (PCA), and (3) applying a Gaussian mixture model (GMM) with Gaussian pdfs as state vector elements on which the native-resolution state vector elements are projected using radial basis functions (RBFs). The GMM method leads to somewhat lower aggregation error than the other methods, but more importantly it retains resolution of major local features in the state vector while smoothing weak and broad features.

Balancing aggregation and smoothing errors in inverse models

NASA Astrophysics Data System (ADS)

Turner, A. J.; Jacob, D. J.

2015-06-01

Inverse models use observations of a system (observation vector) to quantify the variables driving that system (state vector) by statistical optimization. When the observation vector is large, such as with satellite data, selecting a suitable dimension for the state vector is a challenge. A state vector that is too large cannot be effectively constrained by the observations, leading to smoothing error. However, reducing the dimension of the state vector leads to aggregation error as prior relationships between state vector elements are imposed rather than optimized. Here we present a method for quantifying aggregation and smoothing errors as a function of state vector dimension, so that a suitable dimension can be selected by minimizing the combined error. Reducing the state vector within the aggregation error constraints can have the added advantage of enabling analytical solution to the inverse problem with full error characterization. We compare three methods for reducing the dimension of the state vector from its native resolution: (1) merging adjacent elements (grid coarsening), (2) clustering with principal component analysis (PCA), and (3) applying a Gaussian mixture model (GMM) with Gaussian pdfs as state vector elements on which the native-resolution state vector elements are projected using radial basis functions (RBFs). The GMM method leads to somewhat lower aggregation error than the other methods, but more importantly it retains resolution of major local features in the state vector while smoothing weak and broad features.

Declining Prevalence of Disease Vectors Under Climate Change

NASA Astrophysics Data System (ADS)

Escobar, Luis E.; Romero-Alvarez, Daniel; Leon, Renato; Lepe-Lopez, Manuel A.; Craft, Meggan E.; Borbor-Cordova, Mercy J.; Svenning, Jens-Christian

2016-12-01

More than half of the world population is at risk of vector-borne diseases including dengue fever, chikungunya, zika, yellow fever, leishmaniasis, chagas disease, and malaria, with highest incidences in tropical regions. In Ecuador, vector-borne diseases are present from coastal and Amazonian regions to the Andes Mountains; however, a detailed characterization of the distribution of their vectors has never been carried out. We estimate the distribution of 14 vectors of the above vector-borne diseases under present-day and future climates. Our results consistently suggest that climate warming is likely threatening some vector species with extinction, locally or completely. These results suggest that climate change could reduce the burden of specific vector species. Other vector species are likely to shift and constrain their geographic range to the highlands in Ecuador potentially affecting novel areas and populations. These forecasts show the need for development of early prevention strategies for vector species currently absent in areas projected as suitable under future climate conditions. Informed interventions could reduce the risk of human exposure to vector species with distributional shifts, in response to current and future climate changes. Based on the mixed effects of future climate on human exposure to disease vectors, we argue that research on vector-borne diseases should be cross-scale and include climatic, demographic, and landscape factors, as well as forces facilitating disease transmission at fine scales.

Multineuronal vectorization is more efficient than time-segmental vectorization for information extraction from neuronal activities in the inferior temporal cortex.

PubMed

Kaneko, Hidekazu; Tamura, Hiroshi; Tate, Shunta; Kawashima, Takahiro; Suzuki, Shinya S; Fujita, Ichiro

2010-08-01

In order for patients with disabilities to control assistive devices with their own neural activity, multineuronal spike trains must be efficiently decoded because only limited computational resources can be used to generate prosthetic control signals in portable real-time applications. In this study, we compare the abilities of two vectorizing procedures (multineuronal and time-segmental) to extract information from spike trains during the same total neuron-seconds. In the multineuronal vectorizing procedure, we defined a response vector whose components represented the spike counts of one to five neurons. In the time-segmental vectorizing procedure, a response vector consisted of components representing a neuron's spike counts for one to five time-segment(s) of a response period of 1 s. Spike trains were recorded from neurons in the inferior temporal cortex of monkeys presented with visual stimuli. We examined whether the amount of information of the visual stimuli carried by these neurons differed between the two vectorizing procedures. The amount of information calculated with the multineuronal vectorizing procedure, but not the time-segmental vectorizing procedure, significantly increased with the dimensions of the response vector. We conclude that the multineuronal vectorizing procedure is superior to the time-segmental vectorizing procedure in efficiently extracting information from neuronal signals. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Large Animal Models for Foamy Virus Vector Gene Therapy

PubMed Central

Trobridge, Grant D.; Horn, Peter A.; Beard, Brian C.; Kiem, Hans-Peter

2012-01-01

Foamy virus (FV) vectors have shown great promise for hematopoietic stem cell (HSC) gene therapy. Their ability to efficiently deliver transgenes to multi-lineage long-term repopulating cells in large animal models suggests they will be effective for several human hematopoietic diseases. Here, we review FV vector studies in large animal models, including the use of FV vectors with the mutant O6-methylguanine-DNA methyltransferase, MGMTP140K to increase the number of genetically modified cells after transplantation. In these studies, FV vectors have mediated efficient gene transfer to polyclonal repopulating cells using short ex vivo transduction protocols designed to minimize the negative effects of ex vivo culture on stem cell engraftment. In this regard, FV vectors appear superior to gammaretroviral vectors, which require longer ex vivo culture to effect efficient transduction. FV vectors have also compared favorably with lentiviral vectors when directly compared in the dog model. FV vectors have corrected leukocyte adhesion deficiency and pyruvate kinase deficiency in the dog large animal model. FV vectors also appear safer than gammaretroviral vectors based on a reduced frequency of integrants near promoters and also near proto-oncogenes in canine repopulating cells. Together, these studies suggest that FV vectors should be highly effective for several human hematopoietic diseases, including those that will require relatively high percentages of gene-modified cells to achieve clinical benefit. PMID:23223198

Helminths as vectors of pathogens in vertebrate hosts: a theoretical approach.

PubMed

Perkins, Sarah E; Fenton, Andy

2006-07-01

Pathogens frequently use vectors to facilitate transmission between hosts and, for vertebrate hosts, the vectors are typically ectoparasitic arthropods. However, other parasites that are intimately associated with their hosts may also be ideal candidate vectors; namely the parasitic helminths. Here, we present empirical evidence that helminth vectoring of pathogens occurs in a range of vertebrate systems by a variety of helminth taxa. Using a novel theoretical framework we explore the dynamics of helminth vectoring and determine which host-helminth-pathogen characteristics may favour the evolution of helminth vectoring. We use two theoretical models: the first is a population dynamic model amalgamated from standard macro- and microparasite models, which serves as a framework for investigation of within-host interactions between co-infecting pathogens and helminths. The second is an evolutionary model, which we use to predict the ecological conditions under which we would expect helminth vectoring to evolve. We show that, like arthropod vectors, helminth vectors increase pathogen fitness. However, unlike arthropod vectors, helminth vectoring increases the pathogenic impact on the host and may allow the evolution of high pathogen virulence. We show that concomitant infection of a host with a helminth and pathogen are not necessarily independent of one another, due to helminth vectoring of microparasites, with profound consequences for pathogen persistence and the impact of disease on the host population.

Impact of Vector Dispersal and Host-Plant Fidelity on the Dissemination of an Emerging Plant Pathogen

PubMed Central

Johannesen, Jes; Foissac, Xavier; Kehrli, Patrik; Maixner, Michael

2012-01-01

Dissemination of vector-transmitted pathogens depend on the survival and dispersal of the vector and the vector's ability to transmit the pathogen, while the host range of vector and pathogen determine the breath of transmission possibilities. In this study, we address how the interaction between dispersal and plant fidelities of a pathogen (stolbur phytoplasma tuf-a) and its vector (Hyalesthes obsoletus: Cixiidae) affect the emergence of the pathogen. Using genetic markers, we analysed the geographic origin and range expansion of both organisms in Western Europe and, specifically, whether the pathogen's dissemination in the northern range is caused by resident vectors widening their host-plant use from field bindweed to stinging nettle, and subsequent host specialisation. We found evidence for common origins of pathogen and vector south of the European Alps. Genetic patterns in vector populations show signals of secondary range expansion in Western Europe leading to dissemination of tuf-a pathogens, which might be newly acquired and of hybrid origin. Hence, the emergence of stolbur tuf-a in the northern range was explained by secondary immigration of vectors carrying stinging nettle-specialised tuf-a, not by widening the host-plant spectrum of resident vectors with pathogen transmission from field bindweed to stinging nettle nor by primary co-migration from the resident vector's historical area of origin. The introduction of tuf-a to stinging nettle in the northern range was therefore independent of vector's host-plant specialisation but the rapid pathogen dissemination depended on the vector's host shift, whereas the general dissemination elsewhere was linked to plant specialisation of the pathogen but not of the vector. PMID:23284774

Adeno-Associated Virus Type 6 (AAV6) Vectors Mediate Efficient Transduction of Airway Epithelial Cells in Mouse Lungs Compared to That of AAV2 Vectors

PubMed Central

Halbert, Christine L.; Allen, James M.; Miller, A. Dusty

2001-01-01

Although vectors derived from adeno-associated virus type 2 (AAV2) promote gene transfer and expression in many somatic tissues, studies with animal models and cultured cells show that the apical surface of airway epithelia is resistant to transduction by AAV2 vectors. Approaches to increase transduction rates include increasing the amount of vector and perturbing the integrity of the epithelia. In this study, we explored the use of vectors based on AAV6 to increase transduction rates in airways. AAV vectors were made using combinations of rep, cap, and packaged genomes from AAV2 or AAV6. The packaged genomes encoded human placental alkaline phosphatase and contained terminal repeat sequences from AAV2 or AAV6. We found that transduction efficiency was primarily dependent on the source of Cap protein, defined here as the vector pseudotype. The AAV6 and AAV2 pseudotype vectors exhibited different tropisms in tissue-cultured cells, and cell transduction by AAV6 vectors was not inhibited by heparin, nor did they compete for entry in a transduction assay, indicating that AAV6 and AAV2 capsid bind different receptors. In vivo analysis of vectors showed that AAV2 pseudotype vectors gave high transduction rates in alveolar cells but much lower rates in the airway epithelium. In contrast, the AAV6 pseudotype vectors exhibited much more efficient transduction of epithelial cells in large and small airways, showing up to 80% transduction in some airways. These results, combined with our previous results showing lower immunogenicity of AAV6 than of AAV2 vectors, indicate that AAV6 vectors may provide significant advantages over AAV2 for gene therapy of lung diseases like cystic fibrosis. PMID:11413329

Unrestricted Hepatocyte Transduction with Adeno-Associated Virus Serotype 8 Vectors in Mice

PubMed Central

Nakai, Hiroyuki; Fuess, Sally; Storm, Theresa A.; Muramatsu, Shin-ichi; Nara, Yuko; Kay, Mark A.

2005-01-01

Recombinant adeno-associated virus (rAAV) vectors can mediate long-term stable transduction in various target tissues. However, with rAAV serotype 2 (rAAV2) vectors, liver transduction is confined to only a small portion of hepatocytes even after administration of extremely high vector doses. In order to investigate whether rAAV vectors of other serotypes exhibit similar restricted liver transduction, we performed a dose-response study by injecting mice with β-galactosidase-expressing rAAV1 and rAAV8 vectors via the portal vein. The rAAV1 vector showed a blunted dose-response similar to that of rAAV2 at high doses, while the rAAV8 vector dose-response remained unchanged at any dose and ultimately could transduce all the hepatocytes at a dose of 7.2 × 1012 vector genomes/mouse without toxicity. This indicates that all hepatocytes have the ability to process incoming single-stranded vector genomes into duplex DNA. A single tail vein injection of the rAAV8 vector was as efficient as portal vein injection at any dose. In addition, intravascular administration of the rAAV8 vector at a high dose transduced all the skeletal muscles throughout the body, including the diaphragm, the entire cardiac muscle, and substantial numbers of cells in the pancreas, smooth muscles, and brain. Thus, rAAV8 is a robust vector for gene transfer to the liver and provides a promising research tool for delivering genes to various target organs. In addition, the rAAV8 vector may offer a potential therapeutic agent for various diseases affecting nonhepatic tissues, but great caution is required for vector spillover and tight control of tissue-specific gene expression. PMID:15596817

Impact of vector dispersal and host-plant fidelity on the dissemination of an emerging plant pathogen.

PubMed

Johannesen, Jes; Foissac, Xavier; Kehrli, Patrik; Maixner, Michael

2012-01-01

Dissemination of vector-transmitted pathogens depend on the survival and dispersal of the vector and the vector's ability to transmit the pathogen, while the host range of vector and pathogen determine the breath of transmission possibilities. In this study, we address how the interaction between dispersal and plant fidelities of a pathogen (stolbur phytoplasma tuf-a) and its vector (Hyalesthes obsoletus: Cixiidae) affect the emergence of the pathogen. Using genetic markers, we analysed the geographic origin and range expansion of both organisms in Western Europe and, specifically, whether the pathogen's dissemination in the northern range is caused by resident vectors widening their host-plant use from field bindweed to stinging nettle, and subsequent host specialisation. We found evidence for common origins of pathogen and vector south of the European Alps. Genetic patterns in vector populations show signals of secondary range expansion in Western Europe leading to dissemination of tuf-a pathogens, which might be newly acquired and of hybrid origin. Hence, the emergence of stolbur tuf-a in the northern range was explained by secondary immigration of vectors carrying stinging nettle-specialised tuf-a, not by widening the host-plant spectrum of resident vectors with pathogen transmission from field bindweed to stinging nettle nor by primary co-migration from the resident vector's historical area of origin. The introduction of tuf-a to stinging nettle in the northern range was therefore independent of vector's host-plant specialisation but the rapid pathogen dissemination depended on the vector's host shift, whereas the general dissemination elsewhere was linked to plant specialisation of the pathogen but not of the vector.

Advances in Non-Viral DNA Vectors for Gene Therapy

PubMed Central

Hardee, Cinnamon L.; Arévalo-Soliz, Lirio Milenka; Hornstein, Benjamin D.; Zechiedrich, Lynn

2017-01-01

Uses of viral vectors have thus far eclipsed uses of non-viral vectors for gene therapy delivery in the clinic. Viral vectors, however, have certain issues involving genome integration, the inability to be delivered repeatedly, and possible host rejection. Fortunately, development of non-viral DNA vectors has progressed steadily, especially in plasmid vector length reduction, now allowing these tools to fill in specifically where viral or other non-viral vectors may not be the best options. In this review, we examine the improvements made to non-viral DNA gene therapy vectors, highlight opportunities for their further development, address therapeutic needs for which their use is the logical choice, and discuss their future expansion into the clinic. PMID:28208635

Non-coaxial superposition of vector vortex beams.

PubMed

Aadhi, A; Vaity, Pravin; Chithrabhanu, P; Reddy, Salla Gangi; Prabakar, Shashi; Singh, R P

2016-02-10

Vector vortex beams are classified into four types depending upon spatial variation in their polarization vector. We have generated all four of these types of vector vortex beams by using a modified polarization Sagnac interferometer with a vortex lens. Further, we have studied the non-coaxial superposition of two vector vortex beams. It is observed that the superposition of two vector vortex beams with same polarization singularity leads to a beam with another kind of polarization singularity in their interaction region. The results may be of importance in ultrahigh security of the polarization-encrypted data that utilizes vector vortex beams and multiple optical trapping with non-coaxial superposition of vector vortex beams. We verified our experimental results with theory.

An Algorithm for Converting Static Earth Sensor Measurements into Earth Observation Vectors

NASA Technical Reports Server (NTRS)

Harman, R.; Hashmall, Joseph A.; Sedlak, Joseph

2004-01-01

An algorithm has been developed that converts penetration angles reported by Static Earth Sensors (SESs) into Earth observation vectors. This algorithm allows compensation for variation in the horizon height including that caused by Earth oblateness. It also allows pitch and roll to be computed using any number (greater than 1) of simultaneous sensor penetration angles simplifying processing during periods of Sun and Moon interference. The algorithm computes body frame unit vectors through each SES cluster. It also computes GCI vectors from the spacecraft to the position on the Earth's limb where each cluster detects the Earth's limb. These body frame vectors are used as sensor observation vectors and the GCI vectors are used as reference vectors in an attitude solution. The attitude, with the unobservable yaw discarded, is iteratively refined to provide the Earth observation vector solution.

40 CFR 503.15 - Operational standards-pathogens and vector attraction reduction.

Code of Federal Regulations, 2011 CFR

2011-07-01

... vector attraction reduction. 503.15 Section 503.15 Protection of Environment ENVIRONMENTAL PROTECTION... § 503.15 Operational standards—pathogens and vector attraction reduction. (a) Pathogens—sewage sludge... reclamation site. (c) Vector attraction reduction—sewage sludge. (1) One of the vector attraction reduction...

A Multivariate Model for Prediction of Obstructive Coronary Disease in Patients with Acute Chest Pain: Development and Validation.

PubMed

Correia, Luis Cláudio Lemos; Cerqueira, Maurício; Carvalhal, Manuela; Ferreira, Felipe; Garcia, Guilherme; Silva, André Barcelos da; Sá, Nicole de; Lopes, Fernanda; Barcelos, Ana Clara; Noya-Rabelo, Márcia

2017-04-01

Currently, there is no validated multivariate model to predict probability of obstructive coronary disease in patients with acute chest pain. To develop and validate a multivariate model to predict coronary artery disease (CAD) based on variables assessed at admission to the coronary care unit (CCU) due to acute chest pain. A total of 470 patients were studied, 370 utilized as the derivation sample and the subsequent 100 patients as the validation sample. As the reference standard, angiography was required to rule in CAD (stenosis ≥ 70%), while either angiography or a negative noninvasive test could be used to rule it out. As predictors, 13 baseline variables related to medical history, 14 characteristics of chest discomfort, and eight variables from physical examination or laboratory tests were tested. The prevalence of CAD was 48%. By logistic regression, six variables remained independent predictors of CAD: age, male gender, relief with nitrate, signs of heart failure, positive electrocardiogram, and troponin. The area under the curve (AUC) of this final model was 0.80 (95% confidence interval [95%CI] = 0.75 - 0.84) in the derivation sample and 0.86 (95%CI = 0.79 - 0.93) in the validation sample. Hosmer-Lemeshow's test indicated good calibration in both samples (p = 0.98 and p = 0.23, respectively). Compared with a basic model containing electrocardiogram and troponin, the full model provided an AUC increment of 0.07 in both derivation (p = 0.0002) and validation (p = 0.039) samples. Integrated discrimination improvement was 0.09 in both derivation (p < 0.001) and validation (p < 0.0015) samples. A multivariate model was derived and validated as an accurate tool for estimating the pretest probability of CAD in patients with acute chest pain. Atualmente, não existe um modelo multivariado validado para predizer a probabilidade de doença coronariana obstrutiva em pacientes com dor torácica aguda. Desenvolver e validar um modelo multivariado para predizer doença arterial coronariana (DAC) com base em variáveis avaliadas à admissão na unidade coronariana (UC) devido a dor torácica aguda. Foram estudados um total de 470 pacientes, 370 utilizados como amostra de derivação e os subsequentes 100 pacientes como amostra de validação. Como padrão de referência, a angiografia foi necessária para descartar DAC (estenose ≥ 70%), enquanto a angiografia ou um teste não invasivo negativo foi utilizado para confirmar a doença. Foram testadas como preditoras 13 variáveis basais relacionadas à história médica, 14 características de desconforto torácico e oito variáveis relacionadas ao exame físico ou testes laboratoriais. A prevalência de DAC foi de 48%. Por regressão logística, seis variáveis permaneceram como preditoras independentes de DAC: idade, gênero masculino, alívio com nitrato, sinais de insuficiência cardíaca, e eletrocardiograma e troponina positivos. A área sob a curva (area under the curve, AUC) deste modelo final foi de 0,80 (intervalo de confiança de 95% [IC95%] = 0,75 - 0,84) na amostra de derivação e 0,86 (IC95% = 0,79 - 0,93) na amostra de validação. O teste de Hosmer-Lemeshow indicou uma boa calibração em ambas as amostras (p = 0,98 e p = 0,23, respectivamente). Em comparação com o modelo básico contendo eletrocardiograma e troponina, o modelo completo ofereceu um incremento na AUC de 0,07 tanto na amostra de derivação (p = 0,0002) quanto na de validação (p = 0,039). A melhoria na discriminação integrada foi de 0,09 nas amostras de derivação (p < 0,001) e validação (p < 0,0015). Um modelo multivariado foi derivado e validado como uma ferramenta acurada para estimar a probabilidade pré-teste de DAC em pacientes com dor torácica aguda.

O Electromagnetic Power Waves and Power Density Components.

NASA Astrophysics Data System (ADS)

Petzold, Donald Wayne

1980-12-01

On January 10, 1884 Lord Rayleigh presented a paper entitled "On the Transfer of Energy in the Electromagnetic Field" to the Royal Society of London. This paper had been authored by the late Fellow of Trinity College, Cambridge, Professor J. H. Poynting and in it he claimed that there was a general law for the transfer of electromagnetic energy. He argued that associated with each point in space is a quantity, that has since been called the Poynting vector, that is a measure of the rate of energy flow per unit area. His analysis was concerned with the integration of this power density vector at all points over an enclosing surface of a specific volume. The interpretation of this Poynting vector as a true measure of the local power density was viewed with great skepticism unless the vector was integrated over a closed surface, as the development of the concept required. However, within the last decade or so Shadowitz indicates that a number of prominent authors have argued that the criticism of the interpretation of Poynting's vector as a local power density vector is unjustified. The present paper is not concerned with these arguments but instead is concerned with a decomposition of Poynting's power density vector into two and only two components: one vector which has the same direction as Poynting's vector and which is called the forward power density vector, and another vector, directed opposite to the Poynting vector and called the reverse power density vector. These new local forward and reverse power density vectors will be shown to be dependent upon forward and reverse power wave vectors and these vectors in turn will be related to newly defined forward and reverse components of the electric and magnetic fields. The sum of these forward and reverse power density vectors, which is simply the original Poynting vector, is associated with the total electromagnetic energy traveling past the local point. Another vector which is the difference between the forward and reverse power density vectors and which will be shown to be associated with the total electric and magnetic field energy densities existing at a local point will also be introduced. These local forward and reverse power density vectors may be integrated over a surface to determine the forward and reverse powers and from these results problems related to maximum power transfer or efficiency of electromagnetic energy transmission in space may be studied in a manner similar to that presently being done with transmission lines, wave guides, and more recently with two port multiport lumped parameter systems. These new forward and reverse power density vectors at a point in space are analogous to the forward and revoltages or currents and power waves as used with the transmission line, waveguide, or port. These power wave vectors in space are a generalization of the power waves as developed by Penfield, Youla, and Kurokawa and used with the scattering parameters associated with transmission lines, waveguides and ports.

The Cross Product of Two Vectors Is Not Just Another Vector--A Major Misconception Being Perpetuated in Calculus and Vector Analysis Textbooks.

ERIC Educational Resources Information Center

Elk, Seymour B.

1997-01-01

Suggests that the cross product of two vectors can be more easily and accurately explained by starting from the perspective of dyadics because then the concept of vector multiplication has a simple geometrical picture that encompasses both the dot and cross products in any number of dimensions in terms of orthogonal unit vector components. (AIM)

Application of Genomics for Understanding Plant Virus-Insect Vector Interactions and Insect Vector Control.

PubMed

Kaur, Navneet; Hasegawa, Daniel K; Ling, Kai-Shu; Wintermantel, William M

2016-10-01

The relationships between plant viruses and their vectors have evolved over the millennia, and yet, studies on viruses began <150 years ago and investigations into the virus and vector interactions even more recently. The advent of next generation sequencing, including rapid genome and transcriptome analysis, methods for evaluation of small RNAs, and the related disciplines of proteomics and metabolomics offer a significant shift in the ability to elucidate molecular mechanisms involved in virus infection and transmission by insect vectors. Genomic technologies offer an unprecedented opportunity to examine the response of insect vectors to the presence of ingested viruses through gene expression changes and altered biochemical pathways. This review focuses on the interactions between viruses and their whitefly or thrips vectors and on potential applications of genomics-driven control of the insect vectors. Recent studies have evaluated gene expression in vectors during feeding on plants infected with begomoviruses, criniviruses, and tospoviruses, which exhibit very different types of virus-vector interactions. These studies demonstrate the advantages of genomics and the potential complementary studies that rapidly advance our understanding of the biology of virus transmission by insect vectors and offer additional opportunities to design novel genetic strategies to manage insect vectors and the viruses they transmit.

Gene therapy using retrovirus vectors: vector development and biosafety at clinical trials.

PubMed

Doi, Knayo; Takeuchi, Yasuhiro

2015-01-01

Retrovirus vectors (gammaretroviral and lentiviral vectors) have been considered as promising tools to transfer therapeutic genes into patient cells because they can permanently integrate into host cellular genome. To treat monogenic, inherited diseases, retroviral vectors have been used to add correct genes into patient cells. Conventional gammaretroviral vectors achieved successful results in clinical trials: treated patients had therapeutic gene expression in target cells and had improved symptoms of diseases. However, serious side-effects of leukemia occurred, caused by retroviral insertional mutagenesis (IM). These incidences stressed the importance of monitoring vector integration sites in patient cells as well as of re-consideration on safer vectors. More recently lentiviral vectors which can deliver genes into non-dividing cells started to be used in clinical trials including neurological disorders, showing their efficacy. Vector integration site analysis revealed that lentiviruses integrate less likely to near promoter regions of oncogenes than gammaretroviruses and no adverse events have been reported in lentiviral vector-mediated gene therapy clinical trials. Therefore lentiviral vectors have promises to be applied to a wide range of common diseases in near future. For example, T cells from cancer patients were transduced to express chimeric T cell receptors recognizing their tumour cells enhancing patients' anti-cancer immunity.

Multi-perspective views of students’ difficulties with one-dimensional vector and two-dimensional vector

NASA Astrophysics Data System (ADS)

Fauzi, Ahmad; Ratna Kawuri, Kunthi; Pratiwi, Retno

2017-01-01

Researchers of students’ conceptual change usually collects data from written tests and interviews. Moreover, reports of conceptual change often simply refer to changes in concepts, such as on a test, without any identification of the learning processes that have taken place. Research has shown that students have difficulties with vectors in university introductory physics courses and high school physics courses. In this study, we intended to explore students’ understanding of one-dimensional and two-dimensional vector in multi perspective views. In this research, we explore students’ understanding through test perspective and interviews perspective. Our research study adopted the mixed-methodology design. The participants of this research were sixty students of third semester of physics education department. The data of this research were collected by testand interviews. In this study, we divided the students’ understanding of one-dimensional vector and two-dimensional vector in two categories, namely vector skills of the addition of one-dimensionaland two-dimensional vector and the relation between vector skills and conceptual understanding. From the investigation, only 44% of students provided correct answer for vector skills of the addition of one-dimensional and two-dimensional vector and only 27% students provided correct answer for the relation between vector skills and conceptual understanding.

Mapping of Malaria Vectors at District Level in India: Changing Scenario and Identified Gaps.

PubMed

Singh, Poonam; Lingala, Mercy Aparna L; Sarkar, Soma; Dhiman, Ramesh C

2017-02-01

Malaria is one of the six major vector-borne diseases in India, the endemicity of which changes with changes in ecological, climatic, and sociodevelopmental conditions. The anopheline vectors are greatly affected by ecological conditions such as deforestation, urbanization, climate and lifestyle. Despite the advent of tools such as Geographic Information System (GIS), the updated information on the distribution of anopheline vectors of malaria is not available. In India, the plan for vector control is organized at subcentral level but information about vectors is unavailable even at the district level. Therefore, a systematic presentation of vector distribution has been made to provide maps in respect of major vector species. A search of the literature for major vector species, that is, Anopheles culicifacies, Anopheles fluviatilis, Anopheles stephensi, Anopheles minimus, and Anopheles dirus sensu lato, since 1927 till 2015 was carried out. Data have been presented as present, absent, and no information about vector species during pre-eradication (1927-1958), posteradication (1959-1999), and current scenario (2000-2015). Vectors' distribution and malaria endemicity were mapped using Arc GIS. Of 630 districts of India, major vectors An. culicifacies, An. fluviatilis, and An. stephensi were present in 420, 241, and 243 districts, respectively. In 183 districts, there is no information on any major malaria vector species although 27 of them from the states of Arunachal Pradesh, Jharkhand, Manipur, and Mizoram are highly endemic for malaria, having incidences of 2-40 cases/1000/year. The identified gaps in vector distribution, particularly in malaria endemic areas, necessitate further surveys so as to generate the missing information.

Identification and characterization of a type III secretion-associated chaperone in the type III secretion system 1 of Vibrio parahaemolyticus.

PubMed

Akeda, Yukihiro; Okayama, Kanna; Kimura, Tomomi; Dryselius, Rikard; Kodama, Toshio; Oishi, Kazunori; Iida, Tetsuya; Honda, Takeshi

2009-07-01

Vibrio parahaemolyticus causes human gastroenteritis. Genomic sequencing of this organism has revealed that it has two sets of type III secretion systems, T3SS1 and T3SS2, both of which are important for its pathogenicity. However, the mechanism of protein secretion via T3SSs is unknown. A characteristic of many effectors is that they require specific chaperones for efficient delivery via T3SSs; however, no chaperone has been experimentally identified in the T3SSs of V. parahaemolyticus. In this study, we identified candidate T3SS1-associated chaperones from genomic sequence data and examined their roles in effector secretion/translocation and binding to their cognate substrates. From these experiments, we concluded that there is a T3S-associated chaperone, VecA, for a cytotoxic T3SS1-dependent effector, VepA. Further analysis using pulldown and secretion assays characterized the chaperone-binding domain encompassing the first 30-100 amino acids and an amino terminal secretion signal encompassing the first 5-20 amino acids on VepA. These findings will provide a strategy to clarify how the T3SS1 of V. parahaemolyticus secretes its specific effectors.

Photon beam asymmetry Σ in the reaction γ → p → p ω for E γ = 1.152 to 1.876 GeV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collins, P.; Ritchie, B. G.; Dugger, M.

Photon beam asymmetrymore » $$\\Sigma$$ measurements for $$\\omega$$ photoproduction in the reaction $$\\vec{\\gamma} p \\to \\omega p$$ are reported for photon energies from 1.152 to 1.876 GeV. Data were taken using a linearly-polarized tagged photon beam, a cryogenic hydrogen target, and the CLAS spectrometer in Hall B at Jefferson Lab. The measurements we obtained markedly increase the size of the database for this observable, extend coverage to higher energies, and resolve discrepancies in previously published data. Comparisons of these new results with predictions from a chiral-quark-based model and from a dynamical coupled-channels model indicate the importance of interferences between $t$-channel meson exchange and $s$- and $u$-channel contributions, underscoring sensitivity to the nucleon resonances included in those descriptions. Comparisons with the Bonn-Gatchina partial-wave analysis indicate the $$\\Sigma$$ data reported here help to fix the magnitudes of the interference terms between the leading amplitudes in that calculation (Pomeron exchange and the resonant portion of the $J^P=3/2^+$ partial wave), as well as the resonant portions of the smaller partial waves with $J^P$= $1/2^-$, $3/2^-$, and $5/2^+$.« less

Deep Learning from EEG Reports for Inferring Underspecified Information

PubMed Central

Goodwin, Travis R.; Harabagiu, Sanda M.

2017-01-01

Secondary use1of electronic health records (EHRs) often relies on the ability to automatically identify and extract information from EHRs. Unfortunately, EHRs are known to suffer from a variety of idiosyncrasies – most prevalently, they have been shown to often omit or underspecify information. Adapting traditional machine learning methods for inferring underspecified information relies on manually specifying features characterizing the specific information to recover (e.g. particular findings, test results, or physician’s impressions). By contrast, in this paper, we present a method for jointly (1) automatically extracting word- and report-level features and (2) inferring underspecified information from EHRs. Our approach accomplishes these two tasks jointly by combining recent advances in deep neural learning with access to textual data in electroencephalogram (EEG) reports. We evaluate the performance of our model on the problem of inferring the neurologist’s over-all impression (normal or abnormal) from electroencephalogram (EEG) reports and report an accuracy of 91.4% precision of 94.4% recall of 91.2% and F1 measure of 92.8% (a 40% improvement over the performance obtained using Doc2Vec). These promising results demonstrate the power of our approach, while error analysis reveals remaining obstacles as well as areas for future improvement. PMID:28815118

Technological and Probiotic Traits of the Lactobacilli Isolated From Vaginal Tract of the Healthy Women for Probiotic Use.

PubMed

Bouridane, Hamida; Sifour, Mohamed; Idoui, Tayeb; Annick, Lejeune; Thonard, Philip

2016-09-01

For biotechnological application, selected lactic acid bacteria strains belonging to the genera Lactobacillus (Lb) are proposed as an alternative to the antibiotics for the prevention and treatment of urogenital tract infections. Isolating and selecting vaginal lactobacilli strains for probiotic use based on their technological and probiotic aptitudes. The vaginal isolates were examined for their essential characteristics as the potential probiotic such as low pH tolerance, bile-salt and simulated human intestinal fluid (SIF) resistance, adhesion to the vaginal epithelial cells (VECs), aggregation and coaggregation, surface hydrophobicity, antimicrobial activity, acid production, antibiotic resistance, and resistance to spermicides. The best strain was identified by PCR. From 70 lactobacilli isolates and according to the 16 rDNA sequences, isolates B6 and B10 showed the closest homology (99%) to the Lb. gasseri and Lb. plantarum respectively. They produced hydrogen peroxide (H 2 O 2 ), tolerant to acid, bile, simulated human intestinal fluid, present a strong adhesion, highest percentages of aggregation, and antibacterial activity. These strains are resistant to the spermicide and actively acidify the growth medium. Strains Lb. plantarum B10 and Lb. gasseri B6 have a strong potential probiotic confirming their value as a tool for prevention against urinary and vaginal infections.

Technological and Probiotic Traits of the Lactobacilli Isolated From Vaginal Tract of the Healthy Women for Probiotic Use

PubMed Central

Bouridane, Hamida; Sifour, Mohamed; Idoui, Tayeb; Annick, Lejeune; Thonard, Philip

2016-01-01

Background For biotechnological application, selected lactic acid bacteria strains belonging to the genera Lactobacillus (Lb) are proposed as an alternative to the antibiotics for the prevention and treatment of urogenital tract infections. Objectives Isolating and selecting vaginal lactobacilli strains for probiotic use based on their technological and probiotic aptitudes. Materials and Methods The vaginal isolates were examined for their essential characteristics as the potential probiotic such as low pH tolerance, bile-salt and simulated human intestinal fluid (SIF) resistance, adhesion to the vaginal epithelial cells (VECs), aggregation and coaggregation, surface hydrophobicity, antimicrobial activity, acid production, antibiotic resistance, and resistance to spermicides. The best strain was identified by PCR. Results From 70 lactobacilli isolates and according to the 16 rDNA sequences, isolates B6 and B10 showed the closest homology (99%) to the Lb. gasseri and Lb. plantarum respectively. They produced hydrogen peroxide (H2O2), tolerant to acid, bile, simulated human intestinal fluid, present a strong adhesion, highest percentages of aggregation, and antibacterial activity. These strains are resistant to the spermicide and actively acidify the growth medium. Conclusions Strains Lb. plantarum B10 and Lb. gasseri B6 have a strong potential probiotic confirming their value as a tool for prevention against urinary and vaginal infections. PMID:28959336

Levels of soluble vascular cell adhesion molecule-1 and soluble intercellular adhesion molecule-2 in plasma of patients with hemorrhagic fever with renal syndrome, and significance of the changes in level.

PubMed

Qi, Bao-Tai; Wang, Ping; Li, Jie; Ren, Hui-Xun; Xie, Ming

2006-01-01

Hemorrhagic fever with renal syndrome (HFRS) is an acute viral disease characterized by endothelial dysfunction. Vascular cell adhesion molecule (VCAM)-1 and intercellular adhesion molecule (ICAM)-2 provide costimulatory signals for the activation of T lymphocytes; these adhesion molecules play key roles in leukocyte adherence and propagation of inflammatory responses. They may be involved in the immunologic response that leads to vascular endothelial cell (VEC) and kidney damage of HFRS patients, and increased levels of soluble (s)VCAM-1 and sICAM-2 in plasma may indicate the severity of HFRS. We examined the presence of sVCAM-1 and sICAM-2 in 52 plasma samples collected from 52 patients. We tested these plasma samples for sVCAM-1 and sICAM-2 by double-antibody sandwich ELISA. We found variable, but persistently elevated, levels of sVCAM-1 and sICAM-2 throughout the various phases and types of the disease, which suggested sVCAM-1 may play an important role in the immunopathological lesions of HFRS and is closely correlated to the severity of HFRS and the degree of kidney damage. sICAM-2 may be associated with the hyperfunctioning of the cellular immune response.

Photon beam asymmetry Σ in the reaction γ → p → p ω for E γ = 1.152 to 1.876 GeV

DOE PAGES

Collins, P.; Ritchie, B. G.; Dugger, M.; ...

2017-08-18

Photon beam asymmetrymore » $$\\Sigma$$ measurements for $$\\omega$$ photoproduction in the reaction $$\\vec{\\gamma} p \\to \\omega p$$ are reported for photon energies from 1.152 to 1.876 GeV. Data were taken using a linearly-polarized tagged photon beam, a cryogenic hydrogen target, and the CLAS spectrometer in Hall B at Jefferson Lab. The measurements we obtained markedly increase the size of the database for this observable, extend coverage to higher energies, and resolve discrepancies in previously published data. Comparisons of these new results with predictions from a chiral-quark-based model and from a dynamical coupled-channels model indicate the importance of interferences between $t$-channel meson exchange and $s$- and $u$-channel contributions, underscoring sensitivity to the nucleon resonances included in those descriptions. Comparisons with the Bonn-Gatchina partial-wave analysis indicate the $$\\Sigma$$ data reported here help to fix the magnitudes of the interference terms between the leading amplitudes in that calculation (Pomeron exchange and the resonant portion of the $J^P=3/2^+$ partial wave), as well as the resonant portions of the smaller partial waves with $J^P$= $1/2^-$, $3/2^-$, and $5/2^+$.« less

Release behavior and kinetic evaluation of berberine hydrochloride from ethyl cellulose/chitosan microspheres

NASA Astrophysics Data System (ADS)

Zhou, Hui-Yun; Cao, Pei-Pei; Zhao, Jie; Wang, Zhi-Ying; Li, Jun-Bo; Zhang, Fa-Liang

2014-12-01

Novel ethyl cellulose/chitosan microspheres (ECCMs) were prepared by the method of w/o/w emulsion and solvent evaporation. The microspheres were spherical, adhesive, and aggregated loosely with a size not bigger than 5 μm. The drug loading efficiency of berberine hydrochloride (BH) loaded in microspheres were affected by chitosan (CS) concentration, EC concentration and the volume ratio of V(CS)/ V(EC). ECCMs prepared had sustained release efficiency on BH which was changed with different preparation parameters. In addition, the pH value of release media had obvious effect on the release character of ECCMs. The release rate of BH from sample B was only a little more than 30% in diluted hydrochloric acid (dHCl) and that was almost 90% in PBS during 24 h. Furthermore, the drug release data were fitted to different kinetic models to analyze the release kinetics and the mechanism from the microspheres. The released results of BH indicated that ECCMs exhibited non-Fickian diffusion mechanism in dHCl and diffusion-controlled drug release based on Fickian diffusion in PBS. So the ECCMs might be an ideal sustained release system especially in dHCl and the drug release was governed by both diffusion of the drug and dissolution of the polymeric network.

A pair of new BAC and BIBAC vectors that facilitate BAC/BIBAC library construction and intact large genomic DNA insert exchange.

PubMed

Shi, Xue; Zeng, Haiyang; Xue, Yadong; Luo, Meizhong

2011-10-11

Large-insert BAC and BIBAC libraries are important tools for structural and functional genomics studies of eukaryotic genomes. To facilitate the construction of BAC and BIBAC libraries and the transfer of complete large BAC inserts into BIBAC vectors, which is desired in positional cloning, we developed a pair of new BAC and BIBAC vectors. The new BAC vector pIndigoBAC536-S and the new BIBAC vector BIBAC-S have the following features: 1) both contain two 18-bp non-palindromic I-SceI sites in an inverted orientation at positions that flank an identical DNA fragment containing the lacZ selection marker and the cloning site. Large DNA inserts can be excised from the vectors as single fragments by cutting with I-SceI, allowing the inserts to be easily sized. More importantly, because the two vectors contain different antibiotic resistance genes for transformant selection and produce the same non-complementary 3' protruding ATAA ends by I-SceI that suppress self- and inter-ligations, the exchange of intact large genomic DNA inserts between the BAC and BIBAC vectors is straightforward; 2) both were constructed as high-copy composite vectors. Reliable linearized and dephosphorylated original low-copy pIndigoBAC536-S and BIBAC-S vectors that are ready for library construction can be prepared from the high-copy composite vectors pHZAUBAC1 and pHZAUBIBAC1, respectively, without the need for additional preparation steps or special reagents, thus simplifying the construction of BAC and BIBAC libraries. BIBAC clones constructed with the new BIBAC-S vector are stable in both E. coli and Agrobacterium. The vectors can be accessed through our website http://GResource.hzau.edu.cn. The two new vectors and their respective high-copy composite vectors can largely facilitate the construction and characterization of BAC and BIBAC libraries. The transfer of complete large genomic DNA inserts from one vector to the other is made straightforward.

Dealing with spatial heterogeneity

NASA Astrophysics Data System (ADS)

Marsily, Gh.; Delay, F.; Gonçalvès, J.; Renard, Ph.; Teles, V.; Violette, S.

2005-03-01

Heterogeneity can be dealt with by defining homogeneous equivalent properties, known as averaging, or by trying to describe the spatial variability of the rock properties from geologic observations and local measurements. The techniques available for these descriptions are mostly continuous Geostatistical models, or discontinuous facies models such as the Boolean, Indicator or Gaussian-Threshold models and the Markov chain model. These facies models are better suited to treating issues of rock strata connectivity, e.g. buried high permeability channels or low permeability barriers, which greatly affect flow and, above all, transport in aquifers. Genetic models provide new ways to incorporate more geology into the facies description, an approach that has been well developed in the oil industry, but not enough in hydrogeology. The conclusion is that future work should be focused on improving the facies models, comparing them, and designing new in situ testing procedures (including geophysics) that would help identify the facies geometry and properties. A world-wide catalog of aquifer facies geometry and properties, which could combine site genesis and description with methods used to assess the system, would be of great value for practical applications. On peut aborder le problème de l'hétérogénéité en s'efforçant de définir une perméabilité équivalente homogène, par prise de moyenne, ou au contraire en décrivant la variation dans l'espace des propriétés des roches à partir des observations géologiques et des mesures locales. Les techniques disponibles pour une telle description sont soit continues, comme l'approche Géostatistique, soit discontinues, comme les modèles de faciès, Booléens, ou bien par Indicatrices ou Gaussiennes Seuillées, ou enfin Markoviens. Ces modèles de faciès sont mieux capables de prendre en compte la connectivité des strates géologiques, telles que les chenaux enfouis à forte perméabilité, ou au contraire les faciès fins de barrières de perméabilité, qui ont une influence importante sur les écoulement, et, plus encore, sur le transport. Les modè les génétiques récemment apparus ont la capacité de mieux incorporer dans les modèles de faciès les observations géologiques, chose courante dans l'industrie pétrolière, mais insuffisamment développée en hydrogéologie. On conclut que les travaux de recherche ultérieurs devraient s'attacher à développer les modèles de faciès, à les comparer entre eux, et à mettre au point de nouvelles méthodes d'essais in situ, comprenant les méthodes géophysiques, capables de reconnaître la géométrie et les propriétés des faciès. La constitution d'un catalogue mondial de la géométrie et des propriétés des faciès aquifères, ainsi que des méthodes de reconnaissance utilisées pour arriver à la détermination de ces systèmes, serait d'une grande importance pratique pour les applications. La heterogeneidad se puede manejar por medio de la definición de características homogéneas equivalentes, conocidas como promediar o tratando de describir la variabilidad espacial de las características de las rocas a partir de observaciones geológicas y medidas locales. Las técnicas disponibles para estas descripciones son generalmente modelos geoestadísticos continuos o modelos de facies discontinuos como los modelos Boolean, de Indicador o de umbral de Gaussian y el modelo de cadena de Markow. Estos modelos de facies son mas adecuados para tratar la conectvidad de estratos geológicos (por ejemplo canales de alta permeabilidad enterrados o barreras de baja permeabilidad que tienen efectos importantes sobre el flujo y especialmente sobre el transporte en los acuíferos. Los modelos genéticos ofrecen nuevas formas de incorporar más geología en las descripciones de facies, un enfoque que está bien desarollado en la industria petrolera, pero insuficientemente en la hidrogeología. Se concluye que los trabajos futuros deberían estar más enfocados en mejorar los modelos de facies, en establecer comparaciones y en diseñar nuevos procedimientos para pruebas in-situ (incuyendo la geofísica) que pueden ayudar a identificar la geometría de las facies y sus propiedades. Un catálogo global de la geometría de las facies de los acuíferos y sus características, que podría combinar la génesis de los sitios y descripciones de los métodos utilizados para evaluar el sistema, sería de gran valor para las aplicaciones prácticas.

Rotations with Rodrigues' Vector

ERIC Educational Resources Information Center

Pina, E.

2011-01-01

The rotational dynamics was studied from the point of view of Rodrigues' vector. This vector is defined here by its connection with other forms of parametrization of the rotation matrix. The rotation matrix was expressed in terms of this vector. The angular velocity was computed using the components of Rodrigues' vector as coordinates. It appears…

Study of Equatorial Ionospheric irregularities and Mapping of Electron Density Profiles and Ionograms

DTIC Science & Technology

2012-03-09

equation is a product of a complex basis vector in Jackson and a linear combination of plane wave functions. We convert both the amplitudes and the...wave function arguments from complex scalars to complex vectors . This conversion allows us to separate the electric field vector and the imaginary...magnetic field vector , because exponentials of imaginary scalars convert vectors to imaginary vectors and vice versa, while ex- ponentials of imaginary

Elements of the quality management in the materials' industry

NASA Astrophysics Data System (ADS)

Ioana, Adrian; Semenescu, Augustin; Costoiu, Mihnea; Marcu, Dragoş

2017-12-01

The criteria function concept consists of transforming the criteria function (CF) in a quality-economical matrix math MQE. The levels of prescribing the criteria function was obtained by using a composition algorithm for three vectors: T¯ vector - technical parameters' vector (ti); Ē vector - economical parameters' vector (ej) and P¯ vector - weight vector (p1). For each product or service, the area of the circle represents the value of its sales. The BCG Matrix thus offers a very useful map of the organization's service strengths and weaknesses, at least in terms of current profitability, as well as the likely cash flows.

Vector-transmitted disease vaccines: targeting salivary proteins in transmission (SPIT).

PubMed

McDowell, Mary Ann

2015-08-01

More than half the population of the world is at risk for morbidity and mortality from vector-transmitted diseases, and emerging vector-transmitted infections are threatening new populations. Rising insecticide resistance and lack of efficacious vaccines highlight the need for novel control measures. One such approach is targeting the vector-host interface by incorporating vector salivary proteins in anti-pathogen vaccines. Debate remains about whether vector saliva exposure exacerbates or protects against more severe clinical manifestations, induces immunity through natural exposure or extends to all vector species and associated pathogens. Nevertheless, exploiting this unique biology holds promise as a viable strategy for the development of vaccines against vector-transmitted diseases. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Effects of plant viruses on vector and non-vector herbivorous arthropods and their natural enemies: a mini review].

PubMed

He, Xiao-Chan; Xu, Hong-Xing; Zhou, Xiao-Jun; Zheng, Xu-Song; Sun, Yu-Jian; Yang, Ya-Jun; Tian, Jun-Ce; Lü, Zhong-Xian

2014-05-01

Plant viruses transmitted by arthropods, as an important biotic factor, may not only directly affect the yield and quality of host plants, and development, physiological characteristics and ecological performances of their vector arthropods, but also directly or indirectly affect the non-vector herbivorous arthropods and their natural enemies in the same ecosystem, thereby causing influences to the whole agro-ecosystem. This paper reviewed the progress on the effects of plant viruses on herbivorous arthropods, including vector and non-vector, and their natural enemies, and on their ecological mechanisms to provide a reference for optimizing the management of vector and non-vector arthropod populations and sustainable control of plant viruses in agro-ecosystem.

A Discriminant Distance Based Composite Vector Selection Method for Odor Classification

PubMed Central

Choi, Sang-Il; Jeong, Gu-Min

2014-01-01

We present a composite vector selection method for an effective electronic nose system that performs well even in noisy environments. Each composite vector generated from a electronic nose data sample is evaluated by computing the discriminant distance. By quantitatively measuring the amount of discriminative information in each composite vector, composite vectors containing informative variables can be distinguished and the final composite features for odor classification are extracted using the selected composite vectors. Using the only informative composite vectors can be also helpful to extract better composite features instead of using all the generated composite vectors. Experimental results with different volatile organic compound data show that the proposed system has good classification performance even in a noisy environment compared to other methods. PMID:24747735

Construction and Evaluation of Novel Rhesus Monkey Adenovirus Vaccine Vectors

DOE PAGES

Abbink, Peter; Maxfield, Lori F.; Ng'ang'a, David; ...

2014-11-19

Adenovirus vectors are widely used as vaccine candidates for a variety of pathogens, including HIV-1. To date, human and chimpanzee adenoviruses have been explored in detail as vaccine vectors. Furthermore, the phylogeny of human and chimpanzee adenoviruses is overlapping, and preexisting humoral and cellular immunity to both are exhibited in human populations worldwide. More distantly related adenoviruses may therefore offer advantages as vaccine vectors. We describe the primary isolation and vectorization of three novel adenoviruses from rhesus monkeys. The seroprevalence of these novel rhesus monkey adenovirus vectors was extremely low in sub-Saharan Africa human populations, and these vectors proved tomore » have immunogenicity comparable to that of human and chimpanzee adenovirus vaccine vectors in mice. These rhesus monkey adenoviruses phylogenetically clustered with the poorly described adenovirus species G and robustly stimulated innate immune responses. These novel adenoviruses represent a new class of candidate vaccine vectors.« less

Construction and Evaluation of Novel Rhesus Monkey Adenovirus Vaccine Vectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abbink, Peter; Maxfield, Lori F.; Ng'ang'a, David

Adenovirus vectors are widely used as vaccine candidates for a variety of pathogens, including HIV-1. To date, human and chimpanzee adenoviruses have been explored in detail as vaccine vectors. Furthermore, the phylogeny of human and chimpanzee adenoviruses is overlapping, and preexisting humoral and cellular immunity to both are exhibited in human populations worldwide. More distantly related adenoviruses may therefore offer advantages as vaccine vectors. We describe the primary isolation and vectorization of three novel adenoviruses from rhesus monkeys. The seroprevalence of these novel rhesus monkey adenovirus vectors was extremely low in sub-Saharan Africa human populations, and these vectors proved tomore » have immunogenicity comparable to that of human and chimpanzee adenovirus vaccine vectors in mice. These rhesus monkey adenoviruses phylogenetically clustered with the poorly described adenovirus species G and robustly stimulated innate immune responses. These novel adenoviruses represent a new class of candidate vaccine vectors.« less

Human action classification using procrustes shape theory

NASA Astrophysics Data System (ADS)

Cho, Wanhyun; Kim, Sangkyoon; Park, Soonyoung; Lee, Myungeun

2015-02-01

In this paper, we propose new method that can classify a human action using Procrustes shape theory. First, we extract a pre-shape configuration vector of landmarks from each frame of an image sequence representing an arbitrary human action, and then we have derived the Procrustes fit vector for pre-shape configuration vector. Second, we extract a set of pre-shape vectors from tanning sample stored at database, and we compute a Procrustes mean shape vector for these preshape vectors. Third, we extract a sequence of the pre-shape vectors from input video, and we project this sequence of pre-shape vectors on the tangent space with respect to the pole taking as a sequence of mean shape vectors corresponding with a target video. And we calculate the Procrustes distance between two sequences of the projection pre-shape vectors on the tangent space and the mean shape vectors. Finally, we classify the input video into the human action class with minimum Procrustes distance. We assess a performance of the proposed method using one public dataset, namely Weizmann human action dataset. Experimental results reveal that the proposed method performs very good on this dataset.

Attenuation of Replication-Competent Adenovirus Serotype 26 Vaccines by Vectorization

PubMed Central

Maxfield, Lori F.; Abbink, Peter; Stephenson, Kathryn E.; Borducchi, Erica N.; Ng'ang'a, David; Kirilova, Marinela M.; Paulino, Noelix; Boyd, Michael; Shabram, Paul; Ruan, Qian; Patel, Mayank

2015-01-01

Replication-competent adenovirus (rcAd)-based vaccine vectors may theoretically provide immunological advantages over replication-incompetent Ad vectors, but they also raise additional potential clinical and regulatory issues. We produced replication-competent Ad serotype 26 (rcAd26) vectors by adding the E1 region back into a replication-incompetent Ad26 vector backbone with the E3 or E3/E4 regions deleted. We assessed the effect of vectorization on the replicative capacity of the rcAd26 vaccines. Attenuation occurred in a stepwise fashion, with E3 deletion, E4 deletion, and human immunodeficiency virus type 1 (HIV-1) envelope (Env) gene insertion all contributing to reduced replicative capacity compared to that with the wild-type Ad26 vector. The rcAd26 vector with E3 and E4 deleted and containing the Env transgene exhibited 2.7- to 4.4-log-lower replicative capacity than that of the wild-type Ad26 in vitro. This rcAd26 vector is currently being evaluated in a phase 1 clinical trial. Attenuation as a result of vectorization and transgene insertion has implications for the clinical development of replication-competent vaccine vectors. PMID:26376928

Attenuation of Replication-Competent Adenovirus Serotype 26 Vaccines by Vectorization.

PubMed

Maxfield, Lori F; Abbink, Peter; Stephenson, Kathryn E; Borducchi, Erica N; Ng'ang'a, David; Kirilova, Marinela M; Paulino, Noelix; Boyd, Michael; Shabram, Paul; Ruan, Qian; Patel, Mayank; Barouch, Dan H

2015-11-01

Replication-competent adenovirus (rcAd)-based vaccine vectors may theoretically provide immunological advantages over replication-incompetent Ad vectors, but they also raise additional potential clinical and regulatory issues. We produced replication-competent Ad serotype 26 (rcAd26) vectors by adding the E1 region back into a replication-incompetent Ad26 vector backbone with the E3 or E3/E4 regions deleted. We assessed the effect of vectorization on the replicative capacity of the rcAd26 vaccines. Attenuation occurred in a stepwise fashion, with E3 deletion, E4 deletion, and human immunodeficiency virus type 1 (HIV-1) envelope (Env) gene insertion all contributing to reduced replicative capacity compared to that with the wild-type Ad26 vector. The rcAd26 vector with E3 and E4 deleted and containing the Env transgene exhibited 2.7- to 4.4-log-lower replicative capacity than that of the wild-type Ad26 in vitro. This rcAd26 vector is currently being evaluated in a phase 1 clinical trial. Attenuation as a result of vectorization and transgene insertion has implications for the clinical development of replication-competent vaccine vectors. Copyright © 2015, Maxfield et al.

Epidemiological Implications of Host Biodiversity and Vector Biology: Key Insights from Simple Models.

PubMed

Dobson, Andrew D M; Auld, Stuart K J R

2016-04-01

Models used to investigate the relationship between biodiversity change and vector-borne disease risk often do not explicitly include the vector; they instead rely on a frequency-dependent transmission function to represent vector dynamics. However, differences between classes of vector (e.g., ticks and insects) can cause discrepancies in epidemiological responses to environmental change. Using a pair of disease models (mosquito- and tick-borne), we simulated substitutive and additive biodiversity change (where noncompetent hosts replaced or were added to competent hosts, respectively), while considering different relationships between vector and host densities. We found important differences between classes of vector, including an increased likelihood of amplified disease risk under additive biodiversity change in mosquito models, driven by higher vector biting rates. We also draw attention to more general phenomena, such as a negative relationship between initial infection prevalence in vectors and likelihood of dilution, and the potential for a rise in density of infected vectors to occur simultaneously with a decline in proportion of infected hosts. This has important implications; the density of infected vectors is the most valid metric for primarily zoonotic infections, while the proportion of infected hosts is more relevant for infections where humans are a primary host.

Predators indirectly reduce the prevalence of an insect-vectored plant pathogen independent of predator diversity.

PubMed

Long, Elizabeth Y; Finke, Deborah L

2015-04-01

A widely cited benefit of predator diversity is greater suppression of insect herbivores, with corresponding increases in plant biomass. In the context of a vector-borne pathogen system, predator species richness may also influence plant disease risk via the direct effects of predators on the abundance and behavior of herbivores that also act as pathogen vectors. Using an assemblage of generalist insect predators, we examined the relationship between predator species richness and the prevalence of the aphid-vectored cereal yellow dwarf virus in wheat. We found that increasing predator richness enhanced suppression of the vector population and that pathogen prevalence was reduced when predators were present, but the reduction in prevalence was independent of predator species richness. To determine the mechanism(s) by which predator species richness contributes to vector suppression, but not pathogen prevalence, we evaluated vector movement and host plant occupancy in response to predator treatments. We found that pathogen prevalence was unrelated to vector suppression because host plant occupancy by vectors did not vary as a function of vector abundance. However, the presence of predators reduced pathogen prevalence because predators stimulated greater plant-to-plant movement by vectors, which likely diminished vector feeding time and reduced the transmission efficiency of this persistent pathogen. We conclude that community structure (i.e., the presence of predators), but not predator diversity, is a potential factor influencing local plant infection by this insect-vectored pathogen.

Molecular analysis of vector genome structures after liver transduction by conventional and self-complementary adeno-associated viral serotype vectors in murine and nonhuman primate models.

PubMed

Sun, Xun; Lu, You; Bish, Lawrence T; Calcedo, Roberto; Wilson, James M; Gao, Guangping

2010-06-01

Vectors based on several new adeno-associated viral (AAV) serotypes demonstrated strong hepatocyte tropism and transduction efficiency in both small- and large-animal models for liver-directed gene transfer. Efficiency of liver transduction by AAV vectors can be further improved in both murine and nonhuman primate (NHP) animals when the vector genomes are packaged in a self-complementary (sc) format. In an attempt to understand potential molecular mechanism(s) responsible for enhanced transduction efficiency of the sc vector in liver, we performed extensive molecular studies of genome structures of conventional single-stranded (ss) and sc AAV vectors from liver after AAV gene transfer in both mice and NHPs. These included treatment with exonucleases with specific substrate preferences, single-cutter restriction enzyme digestion and polarity-specific hybridization-based vector genome mapping, and bacteriophage phi29 DNA polymerase-mediated and double-stranded circular template-specific rescue of persisted circular genomes. In mouse liver, vector genomes of both genome formats seemed to persist primarily as episomal circular forms, but sc vectors converted into circular forms more rapidly and efficiently. However, the overall differences in vector genome abundance and structure in the liver between ss and sc vectors could not account for the remarkable differences in transduction. Molecular structures of persistent genomes of both ss and sc vectors were significantly more heterogeneous in macaque liver, with noticeable structural rearrangements that warrant further characterizations.

Molecular Analysis of Vector Genome Structures After Liver Transduction by Conventional and Self-Complementary Adeno-Associated Viral Serotype Vectors in Murine and Nonhuman Primate Models

PubMed Central

Sun, Xun; Lu, You; Bish, Lawrence T.; Calcedo, Roberto; Wilson, James M.

2010-01-01

Abstract Vectors based on several new adeno-associated viral (AAV) serotypes demonstrated strong hepatocyte tropism and transduction efficiency in both small- and large-animal models for liver-directed gene transfer. Efficiency of liver transduction by AAV vectors can be further improved in both murine and nonhuman primate (NHP) animals when the vector genomes are packaged in a self-complementary (sc) format. In an attempt to understand potential molecular mechanism(s) responsible for enhanced transduction efficiency of the sc vector in liver, we performed extensive molecular studies of genome structures of conventional single-stranded (ss) and sc AAV vectors from liver after AAV gene transfer in both mice and NHPs. These included treatment with exonucleases with specific substrate preferences, single-cutter restriction enzyme digestion and polarity-specific hybridization-based vector genome mapping, and bacteriophage ϕ29 DNA polymerase-mediated and double-stranded circular template-specific rescue of persisted circular genomes. In mouse liver, vector genomes of both genome formats seemed to persist primarily as episomal circular forms, but sc vectors converted into circular forms more rapidly and efficiently. However, the overall differences in vector genome abundance and structure in the liver between ss and sc vectors could not account for the remarkable differences in transduction. Molecular structures of persistent genomes of both ss and sc vectors were significantly more heterogeneous in macaque liver, with noticeable structural rearrangements that warrant further characterizations. PMID:20113166

High-performance ultra-low power VLSI analog processor for data compression

NASA Technical Reports Server (NTRS)

Tawel, Raoul (Inventor)

1996-01-01

An apparatus for data compression employing a parallel analog processor. The apparatus includes an array of processor cells with N columns and M rows wherein the processor cells have an input device, memory device, and processor device. The input device is used for inputting a series of input vectors. Each input vector is simultaneously input into each column of the array of processor cells in a pre-determined sequential order. An input vector is made up of M components, ones of which are input into ones of M processor cells making up a column of the array. The memory device is used for providing ones of M components of a codebook vector to ones of the processor cells making up a column of the array. A different codebook vector is provided to each of the N columns of the array. The processor device is used for simultaneously comparing the components of each input vector to corresponding components of each codebook vector, and for outputting a signal representative of the closeness between the compared vector components. A combination device is used to combine the signal output from each processor cell in each column of the array and to output a combined signal. A closeness determination device is then used for determining which codebook vector is closest to an input vector from the combined signals, and for outputting a codebook vector index indicating which of the N codebook vectors was the closest to each input vector input into the array.

[What makes an insect a vector?].

PubMed

Kampen, Helge

2009-01-01

Blood-feeding insects transmit numerous viruses, bacteria, protozoans and helminths to vertebrates. The developmental cycles of the microorganisms in their vectors and the mechanisms of transmission are generally extremely complex and the result of a long-lasting coevolution of vector and vectored pathogen based on mutual adaptation. The conditions necessary for an insect to become a vector are multiple but require an innate vector competence as a genetic basis. Next to the vector competence plenty of entomological, ecological and pathogen-related factors are decisive, given the availability of infection sources. The various modes of pathogen transmission by vectors are connected to the developmental routes of the microorganisms in their vectors. In particular, pathogens transmitted by saliva encounter a lot of cellular and acellular barriers during their migration from the insect's midgut through the hemocele into the salivary fluid, including components of the insect's immune system. With regard to intracellular development, receptor-mediated invasion mechanisms are of relevance. As an environmental factor, the temperature has a paramount impact on the vectorial roles of hematophagous insects. Not only has it a considerable influence on the duration of a pathogen's development in its vector (extrinsic incubation period) but it can render putatively vector-incompetent insects to vectors ("leaky gut" phenomenon). Equally crucial are behavioural aspects of both the insect and the pathogen such as blood host preferences, seasonal appearance and circadian biting activity on the vector's side and diurnal/nocturnal periodicity on the pathogen's side which facilitate a contact in the first place.

Vector-Borne Bacterial Plant Pathogens: Interactions with Hemipteran Insects and Plants

PubMed Central

Perilla-Henao, Laura M.; Casteel, Clare L.

2016-01-01

Hemipteran insects are devastating pests of crops due to their wide host range, rapid reproduction, and ability to transmit numerous plant-infecting pathogens as vectors. While the field of plant–virus–vector interactions has flourished in recent years, plant–bacteria–vector interactions remain poorly understood. Leafhoppers and psyllids are by far the most important vectors of bacterial pathogens, yet there are still significant gaps in our understanding of their feeding behavior, salivary secretions, and plant responses as compared to important viral vectors, such as whiteflies and aphids. Even with an incomplete understanding of plant–bacteria–vector interactions, some common themes have emerged: (1) all known vector-borne bacteria share the ability to propagate in the plant and insect host; (2) particular hemipteran families appear to be incapable of transmitting vector-borne bacteria; (3) all known vector-borne bacteria have highly reduced genomes and coding capacity, resulting in host-dependence; and (4) vector-borne bacteria encode proteins that are essential for colonization of specific hosts, though only a few types of proteins have been investigated. Here, we review the current knowledge on important vector-borne bacterial pathogens, including Xylella fastidiosa, Spiroplasma spp., Liberibacter spp., and ‘Candidatus Phytoplasma spp.’. We then highlight recent approaches used in the study of vector-borne bacteria. Finally, we discuss the application of this knowledge for control and future directions that will need to be addressed in the field of vector–plant–bacteria interactions. PMID:27555855

Characteristics of Minimally Oversized Adeno-Associated Virus Vectors Encoding Human Factor VIII Generated Using Producer Cell Lines and Triple Transfection.

PubMed

Nambiar, Bindu; Cornell Sookdeo, Cathleen; Berthelette, Patricia; Jackson, Robert; Piraino, Susan; Burnham, Brenda; Nass, Shelley; Souza, David; O'Riordan, Catherine R; Vincent, Karen A; Cheng, Seng H; Armentano, Donna; Kyostio-Moore, Sirkka

2017-02-01

Several ongoing clinical studies are evaluating recombinant adeno-associated virus (rAAV) vectors as gene delivery vehicles for a variety of diseases. However, the production of vectors with genomes >4.7 kb is challenging, with vector preparations frequently containing truncated genomes. To determine whether the generation of oversized rAAVs can be improved using a producer cell-line (PCL) process, HeLaS3-cell lines harboring either a 5.1 or 5.4 kb rAAV vector genome encoding codon-optimized cDNA for human B-domain deleted Factor VIII (FVIII) were isolated. High-producing "masterwells" (MWs), defined as producing >50,000 vg/cell, were identified for each oversized vector. These MWs provided stable vector production for >20 passages. The quality and potency of the AAVrh8R/FVIII-5.1 and AAVrh8R/FVIII-5.4 vectors generated by the PCL method were then compared to those prepared via transient transfection (TXN). Southern and dot blot analyses demonstrated that both production methods resulted in packaging of heterogeneously sized genomes. However, the PCL-derived rAAV vector preparations contained some genomes >4.7 kb, whereas the majority of genomes generated by the TXN method were ≤4.7 kb. The PCL process reduced packaging of non-vector DNA for both the AAVrh8R/FVIII-5.1 and the AAVrh8R/FVIII-5.4 kb vector preparations. Furthermore, more DNA-containing viral particles were obtained for the AAVrh8R/FVIII-5.1 vector. In a mouse model of hemophilia A, animals administered a PCL-derived rAAV vector exhibited twofold higher plasma FVIII activity and increased levels of vector genomes in the liver than mice treated with vector produced via TXN did. Hence, the quality of oversized vectors prepared using the PCL method is greater than that of vectors generated using the TXN process, and importantly this improvement translates to enhanced performance in vivo.

Stability of Lentiviral Vector-Mediated Transgene Expression in the Brain in the Presence of Systemic Antivector Immune Responses

PubMed Central

ABORDO-ADESIDA, EVELYN; FOLLENZI, ANTONIA; BARCIA, CARLOS; SCIASCIA, SANDRA; CASTRO, MARIA G.; NALDINI, LUIGI; LOWENSTEIN, PEDRO R.

2009-01-01

Lentiviral vectors are promising tools for gene therapy in the CNS. It is therefore important to characterize their interactions with the immune system in the CNS. This work characterizes transgene expression and brain inflammation in the presence or absence of immune responses generated after systemic immunization with lentiviral vectors. We characterized transduction with SIN-LV vectors in the CNS. A dose—response curve using SIN-LV-GFP demonstrated detectable transgene expression in the striatum at a dose of 102, and maximum expression at 106, transducing units of lentiviral vector, with minimal increase in inflammatory markers between the lowest and highest dose of vector injected. Our studies demonstrate that injection of a lentiviral vector into the CNS did not cause a measurable inflammatory response. Systemic immunization after CNS injection, with the lentiviral vector expressing the same transgene as a vector injected into the CNS, caused a decrease in transgene expression in the CNS, concomitantly with an infiltration of inflammatory cells into the CNS parenchyma at the injection site. However, peripheral immunization with a lentiviral vector carrying a different transgene did not diminish transgene expression, or cause CNS inflammation. Systemic immunization preceding injection of lentiviral vectors into the CNS determined that preexisting antilentiviral immunity, regardless of the transgene, did not affect transgene expression. Furthermore, we showed that the transgene, but not the virion or vector components, is responsible for providing antigenic epitopes to the activated immune system, on systemic immunization with lentivirus. Low immunogenicity and prolonged transgene expression in the presence of preexisting lentiviral immunity are encouraging data for the future use of lentiviral vectors in CNS gene therapy. In summary, the lentiviral vectors tested induced undetectable activation of innate immune responses, and stimulation of adaptive immune responses against lentiviral vectors was effective in causing a decrease in transgene expression only if the immune response was directed against the transgene. A systemic immune response against vector components alone did not cause brain inflammation, possibly because vector-derived epitopes were not being presented in the CNS. PMID:15960605

Predators indirectly control vector-borne disease: linking predator-prey and host-pathogen models.

PubMed

Moore, Sean M; Borer, Elizabeth T; Hosseini, Parviez R

2010-01-06

Pathogens transmitted by arthropod vectors are common in human populations, agricultural systems and natural communities. Transmission of these vector-borne pathogens depends on the population dynamics of the vector species as well as its interactions with other species within the community. In particular, predation may be sufficient to control pathogen prevalence indirectly via the vector. To examine the indirect effect of predators on vectored-pathogen dynamics, we developed a theoretical model that integrates predator-prey and host-pathogen theory. We used this model to determine whether predation can prevent pathogen persistence or alter the stability of host-pathogen dynamics. We found that, in the absence of predation, pathogen prevalence in the host increases with vector fecundity, whereas predation on the vector causes pathogen prevalence to decline, or even become extinct, with increasing vector fecundity. We also found that predation on a vector may drastically slow the initial spread of a pathogen. The predator can increase host abundance indirectly by reducing or eliminating infection in the host population. These results highlight the importance of studying interactions that, within the greater community, may alter our predictions when studying disease dynamics. From an applied perspective, these results also suggest situations where an introduced predator or the natural enemies of a vector may slow the rate of spread of an emerging vector-borne pathogen.

Analytic calculation of finite-population reproductive numbers for direct- and vector-transmitted diseases with homogeneous mixing.

PubMed

Keegan, Lindsay; Dushoff, Jonathan

2014-05-01

The basic reproductive number, R0, provides a foundation for evaluating how various factors affect the incidence of infectious diseases. Recently, it has been suggested that, particularly for vector-transmitted diseases, R0 should be modified to account for the effects of finite host population within a single disease transmission generation. Here, we use a transmission factor approach to calculate such "finite-population reproductive numbers," under the assumption of homogeneous mixing, for both vector-borne and directly transmitted diseases. In the case of vector-borne diseases, we estimate finite-population reproductive numbers for both host-to-host and vector-to-vector generations, assuming that the vector population is effectively infinite. We find simple, interpretable formulas for all three of these quantities. In the direct case, we find that finite-population reproductive numbers diverge from R0 before R0 reaches half of the population size. In the vector-transmitted case, we find that the host-to-host number diverges at even lower values of R0, while the vector-to-vector number diverges very little over realistic parameter ranges.

Detection of ferromagnetic target based on mobile magnetic gradient tensor system

NASA Astrophysics Data System (ADS)

Gang, Y. I. N.; Yingtang, Zhang; Zhining, Li; Hongbo, Fan; Guoquan, Ren

2016-03-01

Attitude change of mobile magnetic gradient tensor system critically affects the precision of gradient measurements, thereby increasing ambiguity in target detection. This paper presents a rotational invariant-based method for locating and identifying ferromagnetic targets. Firstly, unit magnetic moment vector was derived based on the geometrical invariant, such that the intermediate eigenvector of the magnetic gradient tensor is perpendicular to the magnetic moment vector and the source-sensor displacement vector. Secondly, unit source-sensor displacement vector was derived based on the characteristic that the angle between magnetic moment vector and source-sensor displacement is a rotational invariant. By introducing a displacement vector between two measurement points, the magnetic moment vector and the source-sensor displacement vector were theoretically derived. To resolve the problem of measurement noises existing in the realistic detection applications, linear equations were formulated using invariants corresponding to several distinct measurement points and least square solution of magnetic moment vector and source-sensor displacement vector were obtained. Results of simulation and principal verification experiment showed the correctness of the analytical method, along with the practicability of the least square method.

Large-scale adenovirus and poxvirus-vectored vaccine manufacturing to enable clinical trials.

PubMed

Kallel, Héla; Kamen, Amine A

2015-05-01

Efforts to make vaccines against infectious diseases and immunotherapies for cancer have evolved to utilize a variety of heterologous expression systems such as viral vectors. These vectors are often attenuated or engineered to safely deliver genes encoding antigens of different pathogens. Adenovirus and poxvirus vectors are among the viral vectors that are most frequently used to develop prophylactic vaccines against infectious diseases as well as therapeutic cancer vaccines. This mini-review describes the trends and processes in large-scale production of adenovirus and poxvirus vectors to meet the needs of clinical applications. We briefly describe the general principles for the production and purification of adenovirus and poxvirus viral vectors. Currently, adenovirus and poxvirus vector manufacturing methods rely on well-established cell culture technologies. Several improvements have been evaluated to increase the yield and to reduce the overall manufacturing cost, such as cultivation at high cell densities and continuous downstream processing. Additionally, advancements in vector characterization will greatly facilitate the development of novel vectored vaccine candidates. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of Climate and Climate Change on Vectors and Vector-Borne Diseases: Ticks Are Different.

PubMed

Ogden, Nick H; Lindsay, L Robbin

2016-08-01

There has been considerable debate as to whether global risk from vector-borne diseases will be impacted by climate change. This has focussed on important mosquito-borne diseases that are transmitted by the vectors from infected to uninfected humans. However, this debate has mostly ignored the biological diversity of vectors and vector-borne diseases. Here, we review how climate and climate change may impact those most divergent of arthropod disease vector groups: multivoltine insects and hard-bodied (ixodid) ticks. We contrast features of the life cycles and behaviour of these arthropods, and how weather, climate, and climate change may have very different impacts on the spatiotemporal occurrence and abundance of vectors, and the pathogens they transmit. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

A vectorization of the Jameson-Caughey NYU transonic swept-wing computer program FLO-22-V1 for the STAR-100 computer

NASA Technical Reports Server (NTRS)

Smith, R. E.; Pitts, J. I.; Lambiotte, J. J., Jr.

1978-01-01

The computer program FLO-22 for analyzing inviscid transonic flow past 3-D swept-wing configurations was modified to use vector operations and run on the STAR-100 computer. The vectorized version described herein was called FLO-22-V1. Vector operations were incorporated into Successive Line Over-Relaxation in the transformed horizontal direction. Vector relational operations and control vectors were used to implement upwind differencing at supersonic points. A high speed of computation and extended grid domain were characteristics of FLO-22-V1. The new program was not the optimal vectorization of Successive Line Over-Relaxation applied to transonic flow; however, it proved that vector operations can readily be implemented to increase the computation rate of the algorithm.

Critical Analysis of the Mathematical Formalism of Theoretical Physics. II. Foundations of Vector Calculus

NASA Astrophysics Data System (ADS)

Kalanov, Temur Z.

2014-03-01

A critical analysis of the foundations of standard vector calculus is proposed. The methodological basis of the analysis is the unity of formal logic and of rational dialectics. It is proved that the vector calculus is incorrect theory because: (a) it is not based on a correct methodological basis - the unity of formal logic and of rational dialectics; (b) it does not contain the correct definitions of ``movement,'' ``direction'' and ``vector'' (c) it does not take into consideration the dimensions of physical quantities (i.e., number names, denominate numbers, concrete numbers), characterizing the concept of ''physical vector,'' and, therefore, it has no natural-scientific meaning; (d) operations on ``physical vectors'' and the vector calculus propositions relating to the ''physical vectors'' are contrary to formal logic.

La Educacion Continua de Profesionales de la Salud--Un Modelo para su Desarrollo

ERIC Educational Resources Information Center

Stensland, Per G.

1974-01-01

The author suggests a framework for planning and evaluating continuing education, giving attention to the learner, his objectives, and the learning process; these components are discussed in determining the special characteristics of the continuing education of professional health workers, and a model program is presented. The article is in…

Modelos para la Unificacion de Conceptos, Metodos y Procedimientos Administrativos (Guidelines for Uniform Administrative Concepts, Methods, and Procedures).

ERIC Educational Resources Information Center

Serrano, Jorge A., Ed.

These documents, discussed and approved during the first meeting of the university administrators affiliated with the Federation of Private Universities of Central America and Panama (FUPAC), seek to establish uniform administrative concepts, methods, and procedures, particularly with respect to budgetary matters. The documents define relevant…

La comunidad en el aula y el aula en la comunidad: Un modelo (The Community in the Classroom and the Classroom in the Community: A Model).

ERIC Educational Resources Information Center

Varona, Lucia T.

1999-01-01

Describes an advanced conversational Spanish language course based on community experiences, multicultural education, and collaborative research taught at the University of Santa Clara in California. The class combined authentic materials with real-life experiences. (Author/VWL)

Detectable reporter gene expression following transduction of adenovirus and adeno-associated virus serotype 2 vectors within full-thickness osteoarthritic and unaffected canine cartilage in vitro and unaffected guinea pig cartilage in vivo.

PubMed

Santangelo, Kelly S; Baker, Sarah A; Nuovo, Gerard; Dyce, Jonathan; Bartlett, Jeffrey S; Bertone, Alicia L

2010-02-01

This study quantified and compared the transduction efficiencies of adenoviral (Ad), Arg-Gly-Asp (RGD)-modified Ad, adeno-associated viral serotype 2 (AAV2), and self-complementary AAV2 (scAAV2) vectors within full-thickness osteoarthritic (OA) and unaffected canine cartilage explants in vitro. Intraarticular administration of Ad and scAAV2 vectors was performed to determine the ability of these vectors to transduce unaffected guinea pig cartilage in vivo. Following explant exposure to vector treatment or control, the onset and surface distribution of reporter gene expression was monitored daily with fluorescent microscopy. At termination, explants were divided: one half was digested for analysis using flow cytometry; the remaining portion was used for histology and immunohistochemistry (IHC). Intact articular joints were collected for real-time RT-PCR and IHC to detect reporter gene expression following injection of selected vectors. Ad vector transduced focal areas along the perimeters of explants; the remaining vectors transduced chondrocytes across 100% of the surface. Greater mean transduction efficiencies were found with both AAV2 vectors as compared to the Ad vector (p < or = 0.026). Ad and Ad-RGD vectors transduced only superficial chondrocytes of OA and unaffected cartilage. Uniform reporter gene expression from AAV2 and scAAV2 was detected in the tangential and transitional zones of OA cartilage, but not deeper zones. AAV2 and scAAV2 vectors achieved partial and full-thickness transduction of unaffected cartilage. In vivo work revealed that scAAV2 vector, but not Ad vector, transduced deeper zones of cartilage and menisci. This study demonstrates that AAV2 and scAAV2 are reliable vectors for use in cartilage in vitro and in vivo. (c) 2009 Orthopaedic Research Society.

Video Vectorization via Tetrahedral Remeshing.

PubMed

Wang, Chuan; Zhu, Jie; Guo, Yanwen; Wang, Wenping

2017-02-09

We present a video vectorization method that generates a video in vector representation from an input video in raster representation. A vector-based video representation offers the benefits of vector graphics, such as compactness and scalability. The vector video we generate is represented by a simplified tetrahedral control mesh over the spatial-temporal video volume, with color attributes defined at the mesh vertices. We present novel techniques for simplification and subdivision of a tetrahedral mesh to achieve high simplification ratio while preserving features and ensuring color fidelity. From an input raster video, our method is capable of generating a compact video in vector representation that allows a faithful reconstruction with low reconstruction errors.

Scalar/Vector potential formulation for compressible viscous unsteady flows

NASA Technical Reports Server (NTRS)

Morino, L.

1985-01-01

A scalar/vector potential formulation for unsteady viscous compressible flows is presented. The scalar/vector potential formulation is based on the classical Helmholtz decomposition of any vector field into the sum of an irrotational and a solenoidal field. The formulation is derived from fundamental principles of mechanics and thermodynamics. The governing equations for the scalar potential and vector potential are obtained, without restrictive assumptions on either the equation of state or the constitutive relations or the stress tensor and the heat flux vector.

A Code Generation Approach for Auto-Vectorization in the Spade Compiler

NASA Astrophysics Data System (ADS)

Wang, Huayong; Andrade, Henrique; Gedik, Buğra; Wu, Kun-Lung

We describe an auto-vectorization approach for the Spade stream processing programming language, comprising two ideas. First, we provide support for vectors as a primitive data type. Second, we provide a C++ library with architecture-specific implementations of a large number of pre-vectorized operations as the means to support language extensions. We evaluate our approach with several stream processing operators, contrasting Spade's auto-vectorization with the native auto-vectorization provided by the GNU gcc and Intel icc compilers.

Vector systems for prenatal gene therapy: principles of retrovirus vector design and production.

PubMed

Howe, Steven J; Chandrashekran, Anil

2012-01-01

Vectors derived from the Retroviridae family have several attributes required for successful gene delivery. Retroviral vectors have an adequate payload size for the coding regions of most genes; they are safe to handle and simple to produce. These vectors can be manipulated to target different cell types with low immunogenicity and can permanently insert genetic information into the host cells' genome. Retroviral vectors have been used in gene therapy clinical trials and successfully applied experimentally in vitro, in vivo, and in utero.

High-capacity 'gutless' adenoviral vectors.

PubMed

Kochanek, S; Schiedner, G; Volpers, C

2001-10-01

Adenoviral vectors are promising gene transfer vehicles for different gene therapy applications. High-capacity adenoviral (HC-Ad) vectors address some of the problems that have been observed with replication-defective, E1-deleted first-generation adenoviral vectors: toxicity and immunogenicity due to viral gene expression and 7 to 8 kb capacity limit for the transport of therapeutic DNA. This review summarizes HC-Ad vector-related publications from the past 18 months that are mainly concerned with vector design/production and in vivo applications in different murine models.

Constraining performance assessment models with tracer test results: a comparison between two conceptual models

NASA Astrophysics Data System (ADS)

McKenna, Sean A.; Selroos, Jan-Olof

Tracer tests are conducted to ascertain solute transport parameters of a single rock feature over a 5-m transport pathway. Two different conceptualizations of double-porosity solute transport provide estimates of the tracer breakthrough curves. One of the conceptualizations (single-rate) employs a single effective diffusion coefficient in a matrix with infinite penetration depth. However, the tracer retention between different flow paths can vary as the ratio of flow-wetted surface to flow rate differs between the path lines. The other conceptualization (multirate) employs a continuous distribution of multiple diffusion rate coefficients in a matrix with variable, yet finite, capacity. Application of these two models with the parameters estimated on the tracer test breakthrough curves produces transport results that differ by orders of magnitude in peak concentration and time to peak concentration at the performance assessment (PA) time and length scales (100,000 years and 1,000 m). These differences are examined by calculating the time limits for the diffusive capacity to act as an infinite medium. These limits are compared across both conceptual models and also against characteristic times for diffusion at both the tracer test and PA scales. Additionally, the differences between the models are examined by re-estimating parameters for the multirate model from the traditional double-porosity model results at the PA scale. Results indicate that for each model the amount of the diffusive capacity that acts as an infinite medium over the specified time scale explains the differences between the model results and that tracer tests alone cannot provide reliable estimates of transport parameters for the PA scale. Results of Monte Carlo runs of the transport models with varying travel times and path lengths show consistent results between models and suggest that the variation in flow-wetted surface to flow rate along path lines is insignificant relative to variability in the amount of diffusive capacity that can be accessed along the transport pathway. Contraindre le bilan des performances des modèles avec les résultats de traçages: une comparaison entre deux modèles conceptuels. Des tests de traçage sont mis en oeuvre pour étudier les paramètres de transport de soluté d'une roche sur une longueur de 5 m. Deux différents modèles de transport de soluté dans un milieu à double porosité fournissent des estimation des courbes de restitution. L'une des conceptualisations (unique taux de restitution) emploie un seul coefficient effectif de diffusion dans une matrice possédant une pénétration infinie en profondeur. Par ailleurs, la rétention du traceur entre les différentes lignes d'écoulement peut varier comme le rapport des débits aux surfaces mouillées et comme le rapport de la différence de débits entres les lignes d'écoulement. L'autre conceptualisation (taux multiple) emploie une distribution continue de coefficients de diffusion dans une matrice à capacité variable et finit. L'application de ces deux modèles avec les pa! ramètres estimés grâce aux courbes de restitution produit des résultats de transport qui différent de plusieurs ordres de grandeur dans la magnitude du pic, le temps du pic de concentration, au bilan des performances (PA) et aux échelles de distance (100,000 ans et 1,000 m). Ces différences sont éxaminées par l'intermédiaire des temps limites pour que la capacité diffusive équivaille à un milieu infini. Ces limites sont comparées à travers les modèles conceptuels ainsi que les temps caractéristiques de diffusion à l'échelle du test de traçage et à l'échelle du PA. Par ailleurs, les différences entre les modèles sont éxaminées en réestimant les paramètres pour le modèle à taux multiple à partir des résultats du modèle à double porosité à l'échelle du PA. Les résultats indiquent que pour chaque modèle la valeur de la capacité diffusive dans un milieu infini sur une période de temps spécifiée explique les différences entre les modèles et le ! fait que le test de traçage seul ne permet pas de déterminer les paramètres de transport à l'échelle du PA. Les résultats des simulations Monte Carlo du modèle de transport avec des temps et des distances de transport variables montrent des résultats concordances entre les différents modèles et suggère que la variation que la variation entre surface mouillée et le rapport de la différence de débits entre les lignes d'écoulement est insignifiante, en regard de la variabilité du montant de la capacité diffusive qui peut être accessible le long de la ligne de transport. Delimitando la eficacia de modelos de evaluación con resultados de pruebas de trazadores: una comparación entre dos modelos conceptuales. Se llevaron a cabo pruebas de trazadores para evaluar los parámetros de transporte de solutos en un rasgo rocoso a lo largo de una trayectoria de transporte de 5 m. Dos diferentes conceptualizaciones del transporte de solutos de porosidad doble aportan estimados de las curvas de avance de trazadores. Una de las conceptualizaciones (ritmo único) utiliza un coeficiente de difusión efectiva único en una matriz con profundidad de penetración infinita. Sin embargo, la retención del trazador entre diferentes trayectorias de flujo puede variar debido a que la relación entre la superficie mojada de flujo y el ritmo de flujo difiere entre las líneas de trayectoria. La otra conceptualización (multi-ritmo) utiliza una distribución continua de coeficientes de ritmos de difusión múltiple en una matriz con capacidad variable pero finita. La aplicación de los dos modelos con los parámetros estimados en base a las curvas de avance de trazadores producen resultados de transporte que difieren en varios órdenes de magnitud, tanto en concentración pico como en el tiempo en que se alcanza la concentración pico, en las escalas de evaluación de eficacia (PA) de tiempo y longitud (100,000 años y 1,000 m). Estas diferencias se examinan mediante el cálculo de límites de tiempo en que se considera que la capacidad difusiva actúa como un medio infinito. Estos límites se comparan en ambos modelos conceptuales y contra los tiempos característicos para difusión en escalas de PA y de prueba de trazador. Adicionalmente, se examinan las diferencias entre los modelos calculando de nuevo los parámetros para el modelo multi-ritmo a partir del modelo tradicional de doble porosidad a escala PA. Los resultados indican que para cada modelo la cantidad de la capacidad difusiva que actúa como un medio infinito sobre la escala de tiempo especificada explica las diferencias entre los resultados del modelo y que las pruebas de trazadores por sí solas no aportan cálculos confiables de los parámetros de transporte para la escala PA. Los resultados provenientes de corridas Monte Carlo de los modelos de transporte con distintos tiempos de viaje y diferentes longitudes de trayectorias muestran resultados consistentes entre modelos y sugieren que la variación en la relación de superficie de flujo mojada a ritmo de flujo a lo largo de las líneas de trayectoria es insignificante en relación con la variabilidad en la cantidad de capacidad difusiva que puede alcanzarse a lo largo de la trayectoria de transporte.

Evidence that implicit assumptions of ‘no evolution’ of disease vectors in changing environments can be violated on a rapid timescale

PubMed Central

Egizi, Andrea; Fefferman, Nina H.; Fonseca, Dina M.

2015-01-01

Projected impacts of climate change on vector-borne disease dynamics must consider many variables relevant to hosts, vectors and pathogens, including how altered environmental characteristics might affect the spatial distributions of vector species. However, many predictive models for vector distributions consider their habitat requirements to be fixed over relevant time-scales, when they may actually be capable of rapid evolutionary change and even adaptation. We examine the genetic signature of a spatial expansion by an invasive vector into locations with novel temperature conditions compared to its native range as a proxy for how existing vector populations may respond to temporally changing habitat. Specifically, we compare invasions into different climate ranges and characterize the importance of selection from the invaded habitat. We demonstrate that vector species can exhibit evolutionary responses (altered allelic frequencies) to a temperature gradient in as little as 7–10 years even in the presence of high gene flow, and further, that this response varies depending on the strength of selection. We interpret these findings in the context of climate change predictions for vector populations and emphasize the importance of incorporating vector evolution into models of future vector-borne disease dynamics. PMID:25688024

Re-engineering adenovirus vector systems to enable high-throughput analyses of gene function.

PubMed

Stanton, Richard J; McSharry, Brian P; Armstrong, Melanie; Tomasec, Peter; Wilkinson, Gavin W G

2008-12-01

With the enhanced capacity of bioinformatics to interrogate extensive banks of sequence data, more efficient technologies are needed to test gene function predictions. Replication-deficient recombinant adenovirus (Ad) vectors are widely used in expression analysis since they provide for extremely efficient expression of transgenes in a wide range of cell types. To facilitate rapid, high-throughput generation of recombinant viruses, we have re-engineered an adenovirus vector (designated AdZ) to allow single-step, directional gene insertion using recombineering technology. Recombineering allows for direct insertion into the Ad vector of PCR products, synthesized sequences, or oligonucleotides encoding shRNAs without requirement for a transfer vector Vectors were optimized for high-throughput applications by making them "self-excising" through incorporating the I-SceI homing endonuclease into the vector removing the need to linearize vectors prior to transfection into packaging cells. AdZ vectors allow genes to be expressed in their native form or with strep, V5, or GFP tags. Insertion of tetracycline operators downstream of the human cytomegalovirus major immediate early (HCMV MIE) promoter permits silencing of transgenes in helper cells expressing the tet repressor thus making the vector compatible with the cloning of toxic gene products. The AdZ vector system is robust, straightforward, and suited to both sporadic and high-throughput applications.

Environmental management: a re-emerging vector control strategy.

PubMed

Ault, S K

1994-01-01

Vector control may be accomplished by environmental management (EM), which consists of permanent or long-term modification of the environment, temporary or seasonal manipulation of the environment, and modifying or changing our life styles and practices to reduce human contact with infective vectors. The primary focus of this paper is EM in the control of human malaria, filariasis, arboviruses, Chagas' disease, and schistosomiasis. Modern EM developed as a discipline based primarily in ecologic principles and lessons learned from the adverse environmental impacts of rural development projects. Strategies such as the suppression of vector populations through the provision of safe water supplies, proper sanitation, solid waste management facilities, sewerage and excreta disposal systems, water manipulation in dams and irrigation systems, vector diversion by zooprophylaxis, and vector exclusion by improved housing, are discussed with appropriate examples. Vectors of malaria, filariasis, Chagas' disease, and schistosomiasis have been controlled by drainage or filling aquatic breeding sites, improved housing and sanitation, the use of expanded polystyrene beads, zooprophylaxis, or the provision of household water supplies. Community participation has been effective in the suppression of dengue vectors in Mexico and the Dominican Republic. Alone or combined with other vector control methods, EM has been proven to be a successful approach to vector control in a number of places. The future of EM in vector control looks promising.

Density-dependent host choice by disease vectors: epidemiological implications of the ideal free distribution.

PubMed

Basáñez, María-Gloria; Razali, Karina; Renz, Alfons; Kelly, David

2007-03-01

The proportion of vector blood meals taken on humans (the human blood index, h) appears as a squared term in classical expressions of the basic reproduction ratio (R(0)) for vector-borne infections. Consequently, R(0) varies non-linearly with h. Estimates of h, however, constitute mere snapshots of a parameter that is predicted, from evolutionary theory, to vary with vector and host abundance. We test this prediction using a population dynamics model of river blindness assuming that, before initiation of vector control or chemotherapy, recorded measures of vector density and human infection accurately represent endemic equilibrium. We obtain values of h that satisfy the condition that the effective reproduction ratio (R(e)) must equal 1 at equilibrium. Values of h thus obtained decrease with vector density, decrease with the vector:human ratio and make R(0) respond non-linearly rather than increase linearly with vector density. We conclude that if vectors are less able to obtain human blood meals as their density increases, antivectorial measures may not lead to proportional reductions in R(0) until very low vector levels are achieved. Density dependence in the contact rate of infectious diseases transmitted by insects may be an important non-linear process with implications for their epidemiology and control.

[Construction and selection of effective mouse Smad6 recombinant lenti-virus interference vectors].

PubMed

Yu, Jing; Qi, Mengchun; Deng, Jiupeng; Liu, Gang; Chen, Huaiqing

2010-10-01

This experiment was designed to construct mouse Smad6 recombinant RNA interference vectors and determine their interference effects on bone marrow mesenchymal stem cells (BMSCs). Three recombinant Smad6 RNA interference vectors were constructed by molecular clone techniques with a lenti-virus vector expressing green fluorescent protein (GFP), and the correctness of recombinant vectors was verified by DNA sequencing. Mouse BMSCs were used for transfection experiments and BMP-2 was in use for osteogenic induction of MSCs. The transfection efficiency of recombinant vectors was examined by Laser confocal scanning microscope and the interference effect of recombinant vectors on Smad6 gene expression was determined by real-time RT-PCR and Western blot, respectively. Three Smad6 recombinant RNA interference vectors were successfully constructed and their correctness was proved by DNA sequencing. After transfection, GFPs were effectively expressed in MSCs and all of three recombinant vectors gained high transfection efficiency (> 95%). Both real-time PCR and Western blot examination indicated that among three recombinant vectors, No. 2 Svector had the best interference effect and the interference effect was nearly 91% at protein level. In conclusion, Mouse recombinant Smad6 RNA interference (RNAi) vector was successfully constructed and it provided an effective tool for further studies on BMP signal pathways.

Validation of SplitVectors Encoding for Quantitative Visualization of Large-Magnitude-Range Vector Fields

PubMed Central

Zhao, Henan; Bryant, Garnett W.; Griffin, Wesley; Terrill, Judith E.; Chen, Jian

2017-01-01

We designed and evaluated SplitVectors, a new vector field display approach to help scientists perform new discrimination tasks on large-magnitude-range scientific data shown in three-dimensional (3D) visualization environments. SplitVectors uses scientific notation to display vector magnitude, thus improving legibility. We present an empirical study comparing the SplitVectors approach with three other approaches - direct linear representation, logarithmic, and text display commonly used in scientific visualizations. Twenty participants performed three domain analysis tasks: reading numerical values (a discrimination task), finding the ratio between values (a discrimination task), and finding the larger of two vectors (a pattern detection task). Participants used both mono and stereo conditions. Our results suggest the following: (1) SplitVectors improve accuracy by about 10 times compared to linear mapping and by four times to logarithmic in discrimination tasks; (2) SplitVectors have no significant differences from the textual display approach, but reduce cluttering in the scene; (3) SplitVectors and textual display are less sensitive to data scale than linear and logarithmic approaches; (4) using logarithmic can be problematic as participants' confidence was as high as directly reading from the textual display, but their accuracy was poor; and (5) Stereoscopy improved performance, especially in more challenging discrimination tasks. PMID:28113469

Validation of SplitVectors Encoding for Quantitative Visualization of Large-Magnitude-Range Vector Fields.

PubMed

Henan Zhao; Bryant, Garnett W; Griffin, Wesley; Terrill, Judith E; Jian Chen

2017-06-01

We designed and evaluated SplitVectors, a new vector field display approach to help scientists perform new discrimination tasks on large-magnitude-range scientific data shown in three-dimensional (3D) visualization environments. SplitVectors uses scientific notation to display vector magnitude, thus improving legibility. We present an empirical study comparing the SplitVectors approach with three other approaches - direct linear representation, logarithmic, and text display commonly used in scientific visualizations. Twenty participants performed three domain analysis tasks: reading numerical values (a discrimination task), finding the ratio between values (a discrimination task), and finding the larger of two vectors (a pattern detection task). Participants used both mono and stereo conditions. Our results suggest the following: (1) SplitVectors improve accuracy by about 10 times compared to linear mapping and by four times to logarithmic in discrimination tasks; (2) SplitVectors have no significant differences from the textual display approach, but reduce cluttering in the scene; (3) SplitVectors and textual display are less sensitive to data scale than linear and logarithmic approaches; (4) using logarithmic can be problematic as participants' confidence was as high as directly reading from the textual display, but their accuracy was poor; and (5) Stereoscopy improved performance, especially in more challenging discrimination tasks.

Substitution of blood coagulation factor X-binding to Ad5 by position-specific PEGylation: Preventing vector clearance and preserving infectivity.

PubMed

Krutzke, L; Prill, J M; Engler, T; Schmidt, C Q; Xu, Z; Byrnes, A P; Simmet, T; Kreppel, F

2016-08-10

The biodistribution of adenovirus type 5 (Ad5) vector particles is heavily influenced by interaction of the particles with plasma proteins, including coagulation factor X (FX), which binds specifically to the major Ad5 capsid protein hexon. FX mediates hepatocyte transduction by intravenously-injected Ad5 vectors and shields vector particles from neutralization by natural antibodies and complement. In mice, mutant Ad5 vectors that are ablated for FX-binding become detargeted from hepatocytes, which is desirable for certain applications, but unfortunately such FX-nonbinding vectors also become sensitive to neutralization by mouse plasma proteins. To improve the properties of Ad5 vectors for systemic delivery, we developed a strategy to replace the natural FX shield by a site-specific chemical polyethylene glycol shield. Coupling of polyethylene glycol to a specific site in hexon hypervariable region 1 yielded vector particles that were protected from neutralization by natural antibodies and complement although they were unable to bind FX. These vector particles evaded macrophages in vitro and showed significantly improved pharmacokinetics and hepatocyte transduction in vivo. Thus, site-specific shielding of Ad5 vectors with polyethylene glycol rendered vectors FX-independent and greatly improved their properties for systemic gene therapy. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

The Effects of Climate Change and Globalization on Mosquito Vectors: Evidence from Jeju Island, South Korea on the Potential for Asian Tiger Mosquito (Aedes albopictus) Influxes and Survival from Vietnam Rather Than Japan

PubMed Central

Jeong, Ji Yeon; Yoo, Seung Jin; Koh, Young-Sang; Lee, Seogjae; Heo, Sang Taek; Seong, Seung-Yong; Lee, Keun Hwa

2013-01-01

Background Climate change affects the survival and transmission of arthropod vectors as well as the development rates of vector-borne pathogens. Increased international travel is also an important factor in the spread of vector-borne diseases (VBDs) such as dengue, West Nile, yellow fever, chikungunya, and malaria. Dengue is the most important vector-borne viral disease. An estimated 2.5 billion people are at risk of infection in the world and there are approximately 50 million dengue infections and an estimated 500,000 individuals are hospitalized with dengue haemorrhagic fever annually. The Asian tiger mosquito (Aedes albopictus) is one of the vectors of dengue virus, and populations already exist on Jeju Island, South Korea. Currently, colder winter temperatures kill off Asian tiger mosquito populations and there is no evidence of the mosquitos being vectors for the dengue virus in this location. However, dengue virus-bearing mosquito vectors can inflow to Jeju Island from endemic area such as Vietnam by increased international travel, and this mosquito vector's survival during colder winter months will likely occur due to the effects of climate change. Methods and Results In this section, we show the geographical distribution of medically important mosquito vectors such as Ae. albopictus, a vector of both dengue and chikungunya viruses; Culex pipiens, a vector of West Nile virus; and Anopheles sinensis, a vector of Plasmodium vivax, within Jeju Island, South Korea. We found a significant association between the mean temperature, amount of precipitation, and density of mosquitoes. The phylogenetic analyses show that an Ae. albopictus, collected in southern area of Jeju Island, was identical to specimens found in Ho Chi Minh, Vietnam, and not Nagasaki, Japan. Conclusion Our results suggest that mosquito vectors or virus-bearing vectors can transmit from epidemic regions of Southeast Asia to Jeju Island and can survive during colder winter months. Therefore, Jeju Island is no longer safe from vector borne diseases (VBDs) due to the effects of globalization and climate change, and we should immediately monitor regional climate change to identify newly emerging VBDs. PMID:23894312

Floral traits influence pollen vectors' choices in higher elevation communities in the Himalaya-Hengduan Mountains.

PubMed

Zhao, Yan-Hui; Ren, Zong-Xin; Lázaro, Amparo; Wang, Hong; Bernhardt, Peter; Li, Hai-Dong; Li, De-Zhu

2016-05-24

How floral traits and community composition influence plant specialization is poorly understood and the existing evidence is restricted to regions where plant diversity is low. Here, we assessed whether plant specialization varied among four species-rich subalpine/alpine communities on the Yulong Mountain, SW China (elevation from 2725 to 3910 m). We analyzed two factors (floral traits and pollen vector community composition: richness and density) to determine the degree of plant specialization across 101 plant species in all four communities. Floral visitors were collected and pollen load analyses were conducted to identify and define pollen vectors. Plant specialization of each species was described by using both pollen vector diversity (Shannon's diversity index) and plant selectiveness (d' index), which reflected how selective a given species was relative to available pollen vectors. Pollen vector diversity tended to be higher in communities at lower elevations, while plant selectiveness was significantly lower in a community with the highest proportion of unspecialized flowers (open flowers and clusters of flowers in open inflorescences). In particular, we found that plant species with large and unspecialized flowers attracted a greater diversity of pollen vectors and showed higher selectiveness in their use of pollen vectors. Plant species with large floral displays and high flower abundance were more selective in their exploitation of pollen vectors. Moreover, there was a negative relationship between plant selectiveness and pollen vector density. These findings suggest that flower shape and flower size can increase pollen vector diversity but they also increased plant selectiveness. This indicated that those floral traits that were more attractive to insects increased the diversity of pollen vectors to plants while decreasing overlap among co-blooming plant species for the same pollen vectors. Furthermore, floral traits had a more important impact on the diversity of pollen vectors than the composition of anthophilous insect communities. Plant selectiveness of pollen vectors was strongly influenced by both floral traits and insect community composition. These findings provide a basis for a better understanding of how floral traits and community context shape interactions between flowers and their pollen vectors in species-rich communities.

The effects of climate change and globalization on mosquito vectors: evidence from Jeju Island, South Korea on the potential for Asian tiger mosquito (Aedes albopictus) influxes and survival from Vietnam rather than Japan.

PubMed

Lee, Su Hyun; Nam, Kwang Woo; Jeong, Ji Yeon; Yoo, Seung Jin; Koh, Young-Sang; Lee, Seogjae; Heo, Sang Taek; Seong, Seung-Yong; Lee, Keun Hwa

2013-01-01

Climate change affects the survival and transmission of arthropod vectors as well as the development rates of vector-borne pathogens. Increased international travel is also an important factor in the spread of vector-borne diseases (VBDs) such as dengue, West Nile, yellow fever, chikungunya, and malaria. Dengue is the most important vector-borne viral disease. An estimated 2.5 billion people are at risk of infection in the world and there are approximately 50 million dengue infections and an estimated 500,000 individuals are hospitalized with dengue haemorrhagic fever annually. The Asian tiger mosquito (Aedes albopictus) is one of the vectors of dengue virus, and populations already exist on Jeju Island, South Korea. Currently, colder winter temperatures kill off Asian tiger mosquito populations and there is no evidence of the mosquitos being vectors for the dengue virus in this location. However, dengue virus-bearing mosquito vectors can inflow to Jeju Island from endemic area such as Vietnam by increased international travel, and this mosquito vector's survival during colder winter months will likely occur due to the effects of climate change. In this section, we show the geographical distribution of medically important mosquito vectors such as Ae. albopictus, a vector of both dengue and chikungunya viruses; Culex pipiens, a vector of West Nile virus; and Anopheles sinensis, a vector of Plasmodium vivax, within Jeju Island, South Korea. We found a significant association between the mean temperature, amount of precipitation, and density of mosquitoes. The phylogenetic analyses show that an Ae. albopictus, collected in southern area of Jeju Island, was identical to specimens found in Ho Chi Minh, Vietnam, and not Nagasaki, Japan. Our results suggest that mosquito vectors or virus-bearing vectors can transmit from epidemic regions of Southeast Asia to Jeju Island and can survive during colder winter months. Therefore, Jeju Island is no longer safe from vector borne diseases (VBDs) due to the effects of globalization and climate change, and we should immediately monitor regional climate change to identify newly emerging VBDs.

Project Physics Programmed Instruction, Vectors 1.

ERIC Educational Resources Information Center

Harvard Univ., Cambridge, MA. Harvard Project Physics.

This programmed instruction booklet is an interim version of instructional materials being developed by Harvard Project Physics. It is the first in a series of three booklets on vectors and covers the definitions of vectors and scalars, drawing vector quantities to scale, and negative vectors. For others in this series, see SE 015 550 and SE 015…

Project Physics Programmed Instruction, Vectors 2.

ERIC Educational Resources Information Center

Harvard Univ., Cambridge, MA. Harvard Project Physics.

This is the second of a series of three programmed instruction booklets on vectors developed by Harvard Project Physics. It covers adding two or more vectors together, and finding a third vector that could be added to two given vectors to make a sum of zero. For other booklets in this series, see SE 015 549 and SE 015 551. (DT)

Fluorescent tagged episomals for stoichiometric induced pluripotent stem cell reprogramming.

PubMed

Schmitt, Christopher E; Morales, Blanca M; Schmitz, Ellen M H; Hawkins, John S; Lizama, Carlos O; Zape, Joan P; Hsiao, Edward C; Zovein, Ann C

2017-06-05

Non-integrating episomal vectors have become an important tool for induced pluripotent stem cell reprogramming. The episomal vectors carrying the "Yamanaka reprogramming factors" (Oct4, Klf, Sox2, and L-Myc + Lin28) are critical tools for non-integrating reprogramming of cells to a pluripotent state. However, the reprogramming process remains highly stochastic, and is hampered by an inability to easily identify clones that carry the episomal vectors. We modified the original set of vectors to express spectrally separable fluorescent proteins to allow for enrichment of transfected cells. The vectors were then tested against the standard original vectors for reprogramming efficiency and for the ability to enrich for stoichiometric ratios of factors. The reengineered vectors allow for cell sorting based on reprogramming factor expression. We show that these vectors can assist in tracking episomal expression in individual cells and can select the reprogramming factor dosage. Together, these modified vectors are a useful tool for understanding the reprogramming process and improving induced pluripotent stem cell isolation efficiency.

Increasing the Efficacy of Oncolytic Adenovirus Vectors

PubMed Central

Toth, Karoly; Wold, William S. M.

2010-01-01

Oncolytic adenovirus (Ad) vectors present a new modality to treat cancer. These vectors attack tumors via replicating in and killing cancer cells. Upon completion of the vector replication cycle, the infected tumor cell lyses and releases progeny virions that are capable of infecting neighboring tumor cells. Repeated cycles of vector replication and cell lysis can destroy the tumor. Numerous Ad vectors have been generated and tested, some of them reaching human clinical trials. In 2005, the first oncolytic Ad was approved for the treatment of head-and-neck cancer by the Chinese FDA. Oncolytic Ads have been proven to be safe, with no serious adverse effects reported even when high doses of the vector were injected intravenously. The vectors demonstrated modest anti-tumor effect when applied as a single agent; their efficacy improved when they were combined with another modality. The efficacy of oncolytic Ads can be improved using various approaches, including vector design, delivery techniques, and ancillary treatment, which will be discussed in this review. PMID:21994711

Generation of arbitrary vector fields based on a pair of orthogonal elliptically polarized base vectors.

PubMed

Xu, Danfeng; Gu, Bing; Rui, Guanghao; Zhan, Qiwen; Cui, Yiping

2016-02-22

We present an arbitrary vector field with hybrid polarization based on the combination of a pair of orthogonal elliptically polarized base vectors on the Poincaré sphere. It is shown that the created vector field is only dependent on the latitude angle 2χ but is independent on the longitude angle 2ψ on the Poincaré sphere. By adjusting the latitude angle 2χ, which is related to two identical waveplates in a common path interferometric arrangement, one could obtain arbitrary type of vector fields. Experimentally, we demonstrate the generation of such kind of vector fields and confirm the distribution of state of polarization by the measurement of Stokes parameters. Besides, we investigate the tight focusing properties of these vector fields. It is found that the additional degree of freedom 2χ provided by arbitrary vector field with hybrid polarization allows one to control the spatial structure of polarization and to engineer the focusing field.

Polarization ellipse and Stokes parameters in geometric algebra.

PubMed

Santos, Adler G; Sugon, Quirino M; McNamara, Daniel J

2012-01-01

In this paper, we use geometric algebra to describe the polarization ellipse and Stokes parameters. We show that a solution to Maxwell's equation is a product of a complex basis vector in Jackson and a linear combination of plane wave functions. We convert both the amplitudes and the wave function arguments from complex scalars to complex vectors. This conversion allows us to separate the electric field vector and the imaginary magnetic field vector, because exponentials of imaginary scalars convert vectors to imaginary vectors and vice versa, while exponentials of imaginary vectors only rotate the vector or imaginary vector they are multiplied to. We convert this expression for polarized light into two other representations: the Cartesian representation and the rotated ellipse representation. We compute the conversion relations among the representation parameters and their corresponding Stokes parameters. And finally, we propose a set of geometric relations between the electric and magnetic fields that satisfy an equation similar to the Poincaré sphere equation.

Research on bearing fault diagnosis of large machinery based on mathematical morphology

NASA Astrophysics Data System (ADS)

Wang, Yu

2018-04-01

To study the automatic diagnosis of large machinery fault based on support vector machine, combining the four common faults of the large machinery, the support vector machine is used to classify and identify the fault. The extracted feature vectors are entered. The feature vector is trained and identified by multi - classification method. The optimal parameters of the support vector machine are searched by trial and error method and cross validation method. Then, the support vector machine is compared with BP neural network. The results show that the support vector machines are short in time and high in classification accuracy. It is more suitable for the research of fault diagnosis in large machinery. Therefore, it can be concluded that the training speed of support vector machines (SVM) is fast and the performance is good.

Matrix multiplication operations using pair-wise load and splat operations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eichenberger, Alexandre E.; Gschwind, Michael K.; Gunnels, John A.

Mechanisms for performing a matrix multiplication operation are provided. A vector load operation is performed to load a first vector operand of the matrix multiplication operation to a first target vector register. A pair-wise load and splat operation is performed to load a pair of scalar values of a second vector operand and replicate the pair of scalar values within a second target vector register. An operation is performed on elements of the first target vector register and elements of the second target vector register to generate a partial product of the matrix multiplication operation. The partial product is accumulatedmore » with other partial products and a resulting accumulated partial product is stored. This operation may be repeated for a second pair of scalar values of the second vector operand.« less

Covariantized vector Galileons

NASA Astrophysics Data System (ADS)

Hull, Matthew; Koyama, Kazuya; Tasinato, Gianmassimo

2016-03-01

Vector Galileons are ghost-free systems containing higher derivative interactions of vector fields. They break the vector gauge symmetry, and the dynamics of the longitudinal vector polarizations acquire a Galileon symmetry in an appropriate decoupling limit in Minkowski space. Using an Arnowitt-Deser-Misner approach, we carefully reconsider the coupling with gravity of vector Galileons, with the aim of studying the necessary conditions to avoid the propagation of ghosts. We develop arguments that put on a more solid footing the results previously obtained in the literature. Moreover, working in analogy with the scalar counterpart, we find indications for the existence of a "beyond Horndeski" theory involving vector degrees of freedom that avoids the propagation of ghosts thanks to secondary constraints. In addition, we analyze a Higgs mechanism for generating vector Galileons through spontaneous symmetry breaking, and we present its consistent covariantization.

VISA--Vector Integration Site Analysis server: a web-based server to rapidly identify retroviral integration sites from next-generation sequencing.

PubMed

Hocum, Jonah D; Battrell, Logan R; Maynard, Ryan; Adair, Jennifer E; Beard, Brian C; Rawlings, David J; Kiem, Hans-Peter; Miller, Daniel G; Trobridge, Grant D

2015-07-07

Analyzing the integration profile of retroviral vectors is a vital step in determining their potential genotoxic effects and developing safer vectors for therapeutic use. Identifying retroviral vector integration sites is also important for retroviral mutagenesis screens. We developed VISA, a vector integration site analysis server, to analyze next-generation sequencing data for retroviral vector integration sites. Sequence reads that contain a provirus are mapped to the human genome, sequence reads that cannot be localized to a unique location in the genome are filtered out, and then unique retroviral vector integration sites are determined based on the alignment scores of the remaining sequence reads. VISA offers a simple web interface to upload sequence files and results are returned in a concise tabular format to allow rapid analysis of retroviral vector integration sites.

Large-scale production of lentiviral vector in a closed system hollow fiber bioreactor

PubMed Central

Sheu, Jonathan; Beltzer, Jim; Fury, Brian; Wilczek, Katarzyna; Tobin, Steve; Falconer, Danny; Nolta, Jan; Bauer, Gerhard

2015-01-01

Lentiviral vectors are widely used in the field of gene therapy as an effective method for permanent gene delivery. While current methods of producing small scale vector batches for research purposes depend largely on culture flasks, the emergence and popularity of lentiviral vectors in translational, preclinical and clinical research has demanded their production on a much larger scale, a task that can be difficult to manage with the numbers of producer cell culture flasks required for large volumes of vector. To generate a large scale, partially closed system method for the manufacturing of clinical grade lentiviral vector suitable for the generation of induced pluripotent stem cells (iPSCs), we developed a method employing a hollow fiber bioreactor traditionally used for cell expansion. We have demonstrated the growth, transfection, and vector-producing capability of 293T producer cells in this system. Vector particle RNA titers after subsequent vector concentration yielded values comparable to lentiviral iPSC induction vector batches produced using traditional culture methods in 225 cm2 flasks (T225s) and in 10-layer cell factories (CF10s), while yielding a volume nearly 145 times larger than the yield from a T225 flask and nearly three times larger than the yield from a CF10. Employing a closed system hollow fiber bioreactor for vector production offers the possibility of manufacturing large quantities of gene therapy vector while minimizing reagent usage, equipment footprint, and open system manipulation. PMID:26151065

Development of Peritoneal Tumor-Targeting Vector by In Vivo Screening with a Random Peptide-Displaying Adenovirus Library

PubMed Central

Yoshida, Kimiko; Goto, Naoko; Ohnami, Shumpei; Aoki, Kazunori

2012-01-01

The targeting of gene transfer at the cell-entry level is one of the most attractive challenges in vector development. However, attempts to redirect adenovirus vectors to alternative receptors by engineering the capsid-coding region have shown limited success, because the proper targeting ligands on the cells of interest are generally unknown. To overcome this limitation, we have constructed a random peptide library displayed on the adenoviral fiber knob, and have successfully selected targeted vectors by screening the library on cancer cell lines in vitro. The infection of targeted vectors was considered to be mediated by specific receptors on target cells. However, the expression levels and kinds of cell surface receptors may be substantially different between in vitro culture and in vivo tumor tissue. Here, we screened the peptide display-adenovirus library in the peritoneal dissemination model of AsPC-1 pancreatic cancer cells. The vector displaying a selected peptide (PFWSGAV) showed higher infectivity in the AsPC-1 peritoneal tumors but not in organs and other peritoneal tumors as compared with a non-targeted vector. Furthermore, the infectivity of the PFWSGAV-displaying vector for AsPC-1 peritoneal tumors was significantly higher than that of a vector displaying a peptide selected by in vitro screening, indicating the usefulness of in vivo screening in exploring the targeting vectors. This vector-screening system can facilitate the development of targeted adenovirus vectors for a variety of applications in medicine. PMID:23029088

Practical auxiliary basis implementation of Rung 3.5 functionals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Janesko, Benjamin G., E-mail: b.janesko@tcu.edu; Scalmani, Giovanni; Frisch, Michael J.

2014-07-21

Approximate exchange-correlation functionals for Kohn-Sham density functional theory often benefit from incorporating exact exchange. Exact exchange is constructed from the noninteracting reference system's nonlocal one-particle density matrix γ(r{sup -vector},r{sup -vector}′). Rung 3.5 functionals attempt to balance the strengths and limitations of exact exchange using a new ingredient, a projection of γ(r{sup -vector},r{sup -vector} ′) onto a semilocal model density matrix γ{sub SL}(ρ(r{sup -vector}),∇ρ(r{sup -vector}),r{sup -vector}−r{sup -vector} ′). γ{sub SL} depends on the electron density ρ(r{sup -vector}) at reference point r{sup -vector}, and is closely related to semilocal model exchange holes. We present a practical implementation of Rung 3.5 functionals, expandingmore » the r{sup -vector}−r{sup -vector} ′ dependence of γ{sub SL} in an auxiliary basis set. Energies and energy derivatives are obtained from 3D numerical integration as in standard semilocal functionals. We also present numerical tests of a range of properties, including molecular thermochemistry and kinetics, geometries and vibrational frequencies, and bandgaps and excitation energies. Rung 3.5 functionals typically provide accuracy intermediate between semilocal and hybrid approximations. Nonlocal potential contributions from γ{sub SL} yield interesting successes and failures for band structures and excitation energies. The results enable and motivate continued exploration of Rung 3.5 functional forms.« less

Undetectable Transcription of cap in a Clinical AAV Vector: Implications for Preformed Capsid in Immune Responses

PubMed Central

Hauck, Bernd; Murphy, Samuel L; Smith, Peter H; Qu, Guang; Liu, Xingge; Zelenaia, Olga; Mingozzi, Federico; Sommer, Jürg M; High, Katherine A; Wright, J. Fraser

2008-01-01

In a gene therapy clinical trial for hemophilia B, adeno-associated virus 2 (AAV2) capsid–specific CD8+ T cells were previously implicated in the elimination of vector-transduced hepatocytes, resulting in loss of human factor IX (hFIX) transgene expression. To test the hypothesis that expression of AAV2 cap DNA impurities in the AAV2-hFIX vector was the source of epitopes presented on transduced cells, transcription of cap was assessed by quantitative reverse transcription–PCR (Q-RT-PCR) following transduction of target cells with the vector used in the clinical trial. Transcriptional profiling was also performed for residual AmpR, and adenovirus E2A and E4. Although trace amounts of DNA impurities were present in the clinical vector, transcription of these sequences was not detected after transduction of human hepatocytes, nor in mice administered a dose 26-fold above the highest dose administered in the clinical study. Two methods used to minimize encapsidated DNA impurities in the clinical vector were: (i) a vector (cis) production plasmid with a backbone exceeding the packaging limit of AAV; and (ii) a vector purification step that achieved separation of the vector from vector-related impurities (e.g., empty capsids). In conclusion, residual cap expression was undetectable following transduction with AAV2-hFIX clinical vectors. Preformed capsid protein is implicated as the source of epitopes recognized by CD8+ T cells that eliminated vector-transduced cells in the clinical study. PMID:18941440

Explicación de las disparidades raciales en la salud neonatal en Brasil*

PubMed Central

Nyarko, Kwame A.; López-Camelo, Jorge; Castilla, Eduardo E.; Wehby, George L.

2015-01-01

Objetivos. Buscamos cuantificar la manera en que los efectos socioeconómicos, demográficos, geográficos y de atención de salud explican las disparidades raciales en las tasas de bajo peso al nacer y prematuridad en Brasil. Métodos. Utilizamos una muestra de 8 949 niños nacidos entre 1995 y el 2009 en 15 ciudades y 7 provincias de Brasil. Nos centramos en las disparidades en la prevalencia de bajo peso al nacer (< 2 500 g) y prematuridad (< 37 semanas de gestación) en recién nacidos de ascendencia solo africana o mezclada con otras ascendencias y de ascendencia solo europea. Usamos un modelo de descomposición para cuantificar la contribución de los factores conceptualmente pertinentes a esas disparidades. Resultados. El modelo permitió explicar entre 45% y 94% de las disparidades en cuanto al bajo peso al nacer y entre 64% y 94% de las disparidades en cuanto a la prematuridad entre los grupos de ascendencia africana y de ascendencia europea. Las diferencias en el uso de atención prenatal y en la ubicación geográfica fueron los factores más importantes, seguidos por las diferencias socioeconómicas. El modelo permitió explicar la mayoría de las disparidades en los recién nacidos de ascendencia africana mezclada y parte de las disparidades en los de ascendencia solo africana. Conclusiones. En las políticas públicas para mejorar la salud infantil se deben abordar las diferencias en cuanto a la atención prenatal y la ubicación geográfica a fin de reducir las disparidades en materia de salud entre los recién nacidos de ascendencia africana y los de ascendencia europea en Brasil.

Analysis of groundwater discharge with a lumped-parameter model, using a case study from Tajikistan

NASA Astrophysics Data System (ADS)

Pozdniakov, S. P.; Shestakov, V. M.

A lumped-parameter model of groundwater balance is proposed that permits an estimate of discharge variability in comparison with the variability of recharge, by taking into account the influence of aquifer parameters. Recharge-discharge relationships are analysed with the model for cases of deterministic and stochastic recharge time-series variations. The model is applied to study the temporal variability of groundwater discharge in a river valley in the territory of Tajikistan, an independent republic in Central Asia. Résumé Un modèle global de bilan d'eau souterraine a été développé pour estimer la variabilité de l'écoulement par rapport à celle de la recharge, en prenant en compte l'influence des paramètres de l'aquifère. Les relations entre recharge et écoulement sont analysées à l'aide du modèle pour des variations des chroniques de recharge soit déterministes, soit stochastiques. Le modèle est appliquéà l'étude de la variabilité temporelle de l'écoulement souterrain vers une rivière, dans le Tadjikistan, une république indépendante d'Asie centrale. Resumen Se propone un modelo de parámetros concentrados para realizar el balance de aguas subterráneas, el cual permite estimar la variabilidad en la descarga con respecto a la variabilidad en la recarga, en función de los parámetros que caracterizan el acuífero. Las relaciones entre recarga y descarga se analizan con el modelo para distintos casos de series temporales de recarga, tanto deterministas como estocásticas. El modelo se aplica al estudio de la variabilidad temporal de la descarga en un valle aluvial de Tadyikistán, una república independiente del Asia Central.

A link between torse-forming vector fields and rotational hypersurfaces

NASA Astrophysics Data System (ADS)

Chen, Bang-Yen; Verstraelen, Leopold

Torse-forming vector fields introduced by Yano [On torse forming direction in a Riemannian space, Proc. Imp. Acad. Tokyo 20 (1944) 340-346] are natural extension of concurrent and concircular vector fields. Such vector fields have many nice applications to geometry and mathematical physics. In this paper, we establish a link between rotational hypersurfaces and torse-forming vector fields. More precisely, our main result states that, for a hypersurface M of 𝔼n+1 with n ≥ 3, the tangential component xT of the position vector field of M is a proper torse-forming vector field on M if and only if M is contained in a rotational hypersurface whose axis of rotation contains the origin.

Vectorized Jiles-Atherton hysteresis model

NASA Astrophysics Data System (ADS)

Szymański, Grzegorz; Waszak, Michał

2004-01-01

This paper deals with vector hysteresis modeling. A vector model consisting of individual Jiles-Atherton components placed along principal axes is proposed. The cross-axis coupling ensures general vector model properties. Minor loops are obtained using scaling method. The model is intended for efficient finite element method computations defined in terms of magnetic vector potential. Numerical efficiency is ensured by differential susceptibility approach.

Vector-Based Data Services for NASA Earth Science

NASA Astrophysics Data System (ADS)

Rodriguez, J.; Roberts, J. T.; Ruvane, K.; Cechini, M. F.; Thompson, C. K.; Boller, R. A.; Baynes, K.

2016-12-01

Vector data sources offer opportunities for mapping and visualizing science data in a way that allows for more customizable rendering and deeper data analysis than traditional raster images, and popular formats like GeoJSON and Mapbox Vector Tiles allow diverse types of geospatial data to be served in a high-performance and easily consumed-package. Vector data is especially suited to highly dynamic mapping applications and visualization of complex datasets, while growing levels of support for vector formats and features in open-source mapping clients has made utilizing them easier and more powerful than ever. NASA's Global Imagery Browse Services (GIBS) is working to make NASA data more easily and conveniently accessible than ever by serving vector datasets via GeoJSON, Mapbox Vector Tiles, and raster images. This presentation will review these output formats, the services, including WFS, WMS, and WMTS, that can be used to access the data, and some ways in which vector sources can be utilized in popular open-source mapping clients like OpenLayers. Lessons learned from GIBS' recent move towards serving vector will be discussed, as well as how to use GIBS open source software to create, configure, and serve vector data sources using Mapserver and the GIBS OnEarth Apache module.

Interaction of Flavivirus with their mosquito vectors and their impact on the human health in the Americas.

PubMed

Valderrama, Anayansi; Díaz, Yamilka; López-Vergès, Sandra

2017-10-28

Some of the major arboviruses with public health importance, such as dengue, yellow fever, Zika and West Nile virus are mosquito-borne or mosquito-transmitted Flavivirus. Their principal vectors are from the family Culicidae, Aedes aegypti and Aedes albopictus being responsible of the urban cycles of dengue, Zika and yellow fever virus. These vectors are highly competent for transmission of many arboviruses. The genetic variability of the vectors, the environment and the viral diversity modulate the vector competence, in this context, it is important to determine which vector species is responsible of an outbreak in areas where many vectors coexist. As some vectors can transmit several flaviviruses and some flaviviruses can be transmitted by different species of vectors, through this review we expose importance of yellow fever, dengue and Zika virus in the world and the Americas, as well as the updated knowledge about these flaviviruses in their interaction with their mosquito vectors, guiding us on what is probably the beginning of a new stage in which the simultaneity of outbreaks will occur more frequently. Copyright © 2017 Elsevier Inc. All rights reserved.

Vector and Raster Data Storage Based on Morton Code

NASA Astrophysics Data System (ADS)

Zhou, G.; Pan, Q.; Yue, T.; Wang, Q.; Sha, H.; Huang, S.; Liu, X.

2018-05-01

Even though geomatique is so developed nowadays, the integration of spatial data in vector and raster formats is still a very tricky problem in geographic information system environment. And there is still not a proper way to solve the problem. This article proposes a method to interpret vector data and raster data. In this paper, we saved the image data and building vector data of Guilin University of Technology to Oracle database. Then we use ADO interface to connect database to Visual C++ and convert row and column numbers of raster data and X Y of vector data to Morton code in Visual C++ environment. This method stores vector and raster data to Oracle Database and uses Morton code instead of row and column and X Y to mark the position information of vector and raster data. Using Morton code to mark geographic information enables storage of data make full use of storage space, simultaneous analysis of vector and raster data more efficient and visualization of vector and raster more intuitive. This method is very helpful for some situations that need to analyse or display vector data and raster data at the same time.

Administration of helper-dependent adenoviral vectors and sequential delivery of different vector serotype for long-term liver-directed gene transfer in baboons

PubMed Central

Morral, Núria; O’Neal, Wanda; Rice, Karen; Leland, Michele; Kaplan, Johanne; Piedra, Pedro A.; Zhou, Heshan; Parks, Robin J.; Velji, Rizwan; Aguilar-Córdova, Estuardo; Wadsworth, Samuel; Graham, Frank L.; Kochanek, Stefan; Carey, K. Dee; Beaudet, Arthur L.

1999-01-01

The efficiency of first-generation adenoviral vectors as gene delivery tools is often limited by the short duration of transgene expression, which can be related to immune responses and to toxic effects of viral proteins. In addition, readministration is usually ineffective unless the animals are immunocompromised or a different adenovirus serotype is used. Recently, adenoviral vectors devoid of all viral coding sequences (helper-dependent or gutless vectors) have been developed to avoid expression of viral proteins. In mice, liver-directed gene transfer with AdSTK109, a helper-dependent adenoviral (Ad) vector containing the human α1-antitrypsin (hAAT) gene, resulted in sustained expression for longer than 10 months with negligible toxicity to the liver. In the present report, we have examined the duration of expression of AdSTK109 in the liver of baboons and compared it to first-generation vectors expressing hAAT. Transgene expression was limited to approximately 3–5 months with the first-generation vectors. In contrast, administration of AdSTK109 resulted in transgene expression for longer than a year in two of three baboons. We have also investigated the feasibility of circumventing the humoral response to the virus by sequential administration of vectors of different serotypes. We found that the ineffectiveness of readministration due to the humoral response to an Ad5 first-generation vector was overcome by use of an Ad2-based vector expressing hAAT. These data suggest that long-term expression of transgenes should be possible by combining the reduced immunogenicity and toxicity of helper-dependent vectors with sequential delivery of vectors of different serotypes. PMID:10536005

Hybrid Adeno-Associated Viral Vectors Utilizing Transposase-Mediated Somatic Integration for Stable Transgene Expression in Human Cells

PubMed Central

Zhang, Wenli; Solanki, Manish; Müther, Nadine; Ebel, Melanie; Wang, Jichang; Sun, Chuanbo; Izsvak, Zsuzsanna; Ehrhardt, Anja

2013-01-01

Recombinant adeno-associated viral (AAV) vectors have been shown to be one of the most promising vectors for therapeutic gene delivery because they can induce efficient and long-term transduction in non-dividing cells with negligible side-effects. However, as AAV vectors mostly remain episomal, vector genomes and transgene expression are lost in dividing cells. Therefore, to stably transduce cells, we developed a novel AAV/transposase hybrid-vector. To facilitate SB-mediated transposition from the rAAV genome, we established a system in which one AAV vector contains the transposon with the gene of interest and the second vector delivers the hyperactive Sleeping Beauty (SB) transposase SB100X. Human cells were infected with the AAV-transposon vector and the transposase was provided in trans either by transient and stable plasmid transfection or by AAV vector transduction. We found that groups which received the hyperactive transposase SB100X showed significantly increased colony forming numbers indicating enhanced integration efficiencies. Furthermore, we found that transgene copy numbers in transduced cells were dose-dependent and that predominantly SB transposase-mediated transposition contributed to stabilization of the transgene. Based on a plasmid rescue strategy and a linear-amplification mediated PCR (LAM-PCR) protocol we analysed the SB100X-mediated integration profile after transposition from the AAV vector. A total of 1840 integration events were identified which revealed a close to random integration profile. In summary, we show for the first time that AAV vectors can serve as template for SB transposase mediated somatic integration. We developed the first prototype of this hybrid-vector system which with further improvements may be explored for treatment of diseases which originate from rapidly dividing cells. PMID:24116154

Mosquito biting activity on humans & detection of Plasmodium falciparum infection in Anopheles stephensi in Goa, India.

PubMed

Korgaonkar, Nandini S; Kumar, Ashwani; Yadav, Rajpal S; Kabadi, Dipak; Dash, Aditya P

2012-01-01

Knowledge of the bionomics of mosquitoes, especially of disease vectors, is essential to plan appropriate vector avoidance and control strategies. Information on biting activity of vectors during the night hours in different seasons is important for choosing personal protection measures. This study was carried out to find out the composition of mosquito fauna biting on humans and seasonal biting trends in Goa, India. Biting activities of all mosquitoes including vectors were studied from 1800 to 0600 h during 85 nights using human volunteers in 14 different localities of three distinct ecotypes in Goa. Seasonal biting trends of vector species were analysed and compared. Seasonal biting periodicity during different phases of night was also studied using William's mean. A total of 4,191 mosquitoes of five genera and 23 species were collected. Ten species belonged to Anopheles, eight to Culex, three to Aedes and one each to Mansonia and Armigeres. Eleven vector species had human hosts, including malaria vectors Anopheles stephensi (1.3%), An. fluviatilis (1.8%), and An. culicifacies (0.76%); filariasis vectors Culex quinquefasciatus (40.8%) and Mansonia uniformis (1.8%); Japanese encephalitis vectors Cx. tritaeniorhynchus (17.4%), Cx. vishnui (7.7%), Cx. pseudovishnui (0.1%), and Cx. gelidus (2.4%); and dengue and chikungunya vectors Aedes albopictus (0.9%) and Ae. aegypti (0.6%). Two An. stephensi of the total 831 female anophelines, were found positive for P. falciparum sporozoites. The entomological inoculation rate (EIR) of P. falciparum was 18.1 and 2.35 for Panaji city and Goa, respectively. Most of the mosquito vector species were collected in all seasons and throughout the scotophase. Biting rates of different vector species differed during different phases of night and seasons. Personal protection methods could be used to stop vector-host contact.

Avidin-Based Targeting and Purification of a Protein IX-Modified, Metabolically Biotinylated Adenoviral Vector

PubMed Central

Campos, Samuel K.; Parrott, M. Brandon; Barry, Michael A.

2014-01-01

While genetic modification of adenoviral vectors can produce vectors with modified tropism, incorporation of targeting peptides/proteins into the structural context of the virion can also result in destruction of ligand targeting or virion integrity. To combat this problem, we have developed a versatile targeting system using metabolically biotinylated adenoviral vectors bearing biotinylated fiber proteins. These vectors have been demonstrated to be useful as a platform for avidin-based ligand screening and vector targeting by conjugating biotinylated ligands to the virus using high-affinity tetrameric avidin (Kd = 10−15 M). The biotinylated vector could also be purified by biotin-reversible binding on monomeric avidin (Kd = 10−7 M). In this report, a second metabolically biotinylated adenovirus vector, Ad-IX-BAP, has been engineered by fusing a biotin acceptor peptide (BAP) to the C-terminus of the adenovirus pIX protein. This biotinylated vector displays twice as many biotins and was markedly superior for single-step affinity purification on monomeric avidin resin. However, unlike the fiber-biotinylated vector, Ad-IX-BAP failed to retarget to cells with biotinylated antibodies including anti-CD71 against the transferrin receptor. In contrast, Ad-IX-BAP was retargeted if transferrin, the cognate ligand for CD71, was used as a ligand rather than the anti-CD71. This work demonstrates the utility of metabolic biotinylation as a molecular screening tool to assess the utility of different viral capsid proteins for ligand display and the biology and compatibility of different ligands and receptors for vector targeting applications. These results also demonstrate the utility of the pIX-biotinylated vector as a platform for gentle single-step affinity purification of adenoviral vectors. PMID:15194061

Co-occurrence of viruses and mosquitoes at the vectors' optimal climate range: An underestimated risk to temperate regions?

PubMed

Blagrove, Marcus S C; Caminade, Cyril; Waldmann, Elisabeth; Sutton, Elizabeth R; Wardeh, Maya; Baylis, Matthew

2017-06-01

Mosquito-borne viruses have been estimated to cause over 100 million cases of human disease annually. Many methodologies have been developed to help identify areas most at risk from transmission of these viruses. However, generally, these methodologies focus predominantly on the effects of climate on either the vectors or the pathogens they spread, and do not consider the dynamic interaction between the optimal conditions for both vector and virus. Here, we use a new approach that considers the complex interplay between the optimal temperature for virus transmission, and the optimal climate for the mosquito vectors. Using published geolocated data we identified temperature and rainfall ranges in which a number of mosquito vectors have been observed to co-occur with West Nile virus, dengue virus or chikungunya virus. We then investigated whether the optimal climate for co-occurrence of vector and virus varies between "warmer" and "cooler" adapted vectors for the same virus. We found that different mosquito vectors co-occur with the same virus at different temperatures, despite significant overlap in vector temperature ranges. Specifically, we found that co-occurrence correlates with the optimal climatic conditions for the respective vector; cooler-adapted mosquitoes tend to co-occur with the same virus in cooler conditions than their warmer-adapted counterparts. We conclude that mosquitoes appear to be most able to transmit virus in the mosquitoes' optimal climate range, and hypothesise that this may be due to proportionally over-extended vector longevity, and other increased fitness attributes, within this optimal range. These results suggest that the threat posed by vector-competent mosquito species indigenous to temperate regions may have been underestimated, whilst the threat arising from invasive tropical vectors moving to cooler temperate regions may be overestimated.

The mental health care model in Brazil: analyses of the funding, governance processes, and mechanisms of assessment.

PubMed

Trapé, Thiago Lavras; Campos, Rosana Onocko

2017-03-23

This study aims to analyze the current status of the mental health care model of the Brazilian Unified Health System, according to its funding, governance processes, and mechanisms of assessment. We have carried out a documentary analysis of the ordinances, technical reports, conference reports, normative resolutions, and decrees from 2009 to 2014. This is a time of consolidation of the psychosocial model, with expansion of the health care network and inversion of the funding for community services with a strong emphasis on the area of crack cocaine and other drugs. Mental health is an underfunded area within the chronically underfunded Brazilian Unified Health System. The governance model constrains the progress of essential services, which creates the need for the incorporation of a process of regionalization of the management. The mechanisms of assessment are not incorporated into the health policy in the bureaucratic field. There is a need to expand the global funding of the area of health, specifically mental health, which has been shown to be a successful policy. The current focus of the policy seems to be archaic in relation to the precepts of the psychosocial model. Mechanisms of assessment need to be expanded. Analisar o estágio atual do modelo de atenção à saúde mental do Sistema Único de Saúde, segundo seu financiamento, processos de governança e mecanismos de avaliação. Foi realizada uma análise documental de portarias, informes técnicos, relatórios de conferência, resoluções e decretos de 2009 a 2014. Trata-se de um momento de consolidação do modelo psicossocial, com ampliação da rede assistencial, inversão de financiamento para serviços comunitários com forte ênfase na área de crack e outras drogas. A saúde mental é uma área subfinanciada dentro do subfinanciamento crônico do Sistema Único de Saúde. O modelo de governança constrange o avanço de serviços essenciais, havendo a necessidade da incorporação de um processo de regionalização da gestão. Os mecanismos avaliativos no campo burocrático se mostram pouco incorporados à política de saúde. É necessário ampliar o financiamento global da saúde e específico da saúde mental, que vem se constituindo como uma política exitosa. O foco atual da política se mostra anacrônico aos preceitos do modelo psicossocial. Aponta-se a necessidade de ampliação de mecanismos avaliativos.

Autonomous Environment-Monitoring Networks

NASA Technical Reports Server (NTRS)

Hand, Charles

2004-01-01

Autonomous environment-monitoring networks (AEMNs) are artificial neural networks that are specialized for recognizing familiarity and, conversely, novelty. Like a biological neural network, an AEMN receives a constant stream of inputs. For purposes of computational implementation, the inputs are vector representations of the information of interest. As long as the most recent input vector is similar to the previous input vectors, no action is taken. Action is taken only when a novel vector is encountered. Whether a given input vector is regarded as novel depends on the previous vectors; hence, the same input vector could be regarded as familiar or novel, depending on the context of previous input vectors. AEMNs have been proposed as means to enable exploratory robots on remote planets to recognize novel features that could merit closer scientific attention. AEMNs could also be useful for processing data from medical instrumentation for automated monitoring or diagnosis. The primary substructure of an AEMN is called a spindle. In its simplest form, a spindle consists of a central vector (C), a scalar (r), and algorithms for changing C and r. The vector C is constructed from all the vectors in a given continuous stream of inputs, such that it is minimally distant from those vectors. The scalar r is the distance between C and the most remote vector in the same set. The construction of a spindle involves four vital parameters: setup size, spindle-population size, and the radii of two novelty boundaries. The setup size is the number of vectors that are taken into account before computing C. The spindle-population size is the total number of input vectors used in constructing the spindle counting both those that arrive before and those that arrive after the computation of C. The novelty-boundary radii are distances from C that partition the neighborhood around C into three concentric regions (see Figure 1). During construction of the spindle, the changing spindle radius is denoted by h. It is the final value of h, reached before beginning construction on the next spindle, that is denoted by r. During construction of a spindle, if a new vector falls between C and the inner boundary, the vector is regarded as completely familiar and no action is taken. If the new vector falls into the region between the inner and outer boundaries, it is considered unusual enough to warrant the adjustment of C and r by use of the aforementioned algorithms, but not unusual enough to be considered novel. If a vector falls outside the outer boundary, it is considered novel, in which case one of several appropriate responses could be initiation of construction of a new spindle.

A unified development of several techniques for the representation of random vectors and data sets

NASA Technical Reports Server (NTRS)

Bundick, W. T.

1973-01-01

Linear vector space theory is used to develop a general representation of a set of data vectors or random vectors by linear combinations of orthonormal vectors such that the mean squared error of the representation is minimized. The orthonormal vectors are shown to be the eigenvectors of an operator. The general representation is applied to several specific problems involving the use of the Karhunen-Loeve expansion, principal component analysis, and empirical orthogonal functions; and the common properties of these representations are developed.

Integrating vector control across diseases.

PubMed

Golding, Nick; Wilson, Anne L; Moyes, Catherine L; Cano, Jorge; Pigott, David M; Velayudhan, Raman; Brooker, Simon J; Smith, David L; Hay, Simon I; Lindsay, Steve W

2015-10-01

Vector-borne diseases cause a significant proportion of the overall burden of disease across the globe, accounting for over 10 % of the burden of infectious diseases. Despite the availability of effective interventions for many of these diseases, a lack of resources prevents their effective control. Many existing vector control interventions are known to be effective against multiple diseases, so combining vector control programmes to simultaneously tackle several diseases could offer more cost-effective and therefore sustainable disease reductions. The highly successful cross-disease integration of vaccine and mass drug administration programmes in low-resource settings acts a precedent for cross-disease vector control. Whilst deliberate implementation of vector control programmes across multiple diseases has yet to be trialled on a large scale, a number of examples of 'accidental' cross-disease vector control suggest the potential of such an approach. Combining contemporary high-resolution global maps of the major vector-borne pathogens enables us to quantify overlap in their distributions and to estimate the populations jointly at risk of multiple diseases. Such an analysis shows that over 80 % of the global population live in regions of the world at risk from one vector-borne disease, and more than half the world's population live in areas where at least two different vector-borne diseases pose a threat to health. Combining information on co-endemicity with an assessment of the overlap of vector control methods effective against these diseases allows us to highlight opportunities for such integration. Malaria, leishmaniasis, lymphatic filariasis, and dengue are prime candidates for combined vector control. All four of these diseases overlap considerably in their distributions and there is a growing body of evidence for the effectiveness of insecticide-treated nets, screens, and curtains for controlling all of their vectors. The real-world effectiveness of cross-disease vector control programmes can only be evaluated by large-scale trials, but there is clear evidence of the potential of such an approach to enable greater overall health benefit using the limited funds available.

"Triplet" polycistronic vectors encoding Gata4, Mef2c, and Tbx5 enhances postinfarct ventricular functional improvement compared with singlet vectors.

PubMed

Mathison, Megumi; Singh, Vivek P; Gersch, Robert P; Ramirez, Maricela O; Cooney, Austin; Kaminsky, Stephen M; Chiuchiolo, Maria J; Nasser, Ahmed; Yang, Jianchang; Crystal, Ronald G; Rosengart, Todd K

2014-10-01

The in situ reprogramming of cardiac fibroblasts into induced cardiomyocytes by the administration of gene transfer vectors encoding Gata4 (G), Mef2c (M), and Tbx5 (T) has been shown to improve ventricular function in myocardial infarction models. The efficacy of this strategy could, however, be limited by the need for fibroblast targets to be infected 3 times--once by each of the 3 transgene vectors. We hypothesized that a polycistronic "triplet" vector encoding all 3 transgenes would enhance postinfarct ventricular function compared with use of "singlet" vectors. After validation of the polycistronic vector expression in vitro, adult male Fischer 344 rats (n=6) underwent coronary ligation with or without intramyocardial administration of an adenovirus encoding all 3 major vascular endothelial growth factor (VEGF) isoforms (AdVEGF-All6A positive), followed 3 weeks later by the administration to AdVEGF-All6A-positive treated rats of singlet lentivirus encoding G, M, or T (1×10(5) transducing units each) or the same total dose of a GMT "triplet" lentivirus vector. Western blots demonstrated that triplet and singlet vectors yielded equivalent GMT transgene expression, and fluorescence activated cell sorting demonstrated that triplet vectors were nearly twice as potent as singlet vectors in generating induced cardiomyocytes from cardiac fibroblasts. Echocardiography demonstrated that GMT triplet vectors were more effective than the 3 combined singlet vectors in enhancing ventricular function from postinfarct baselines (triplet, 37%±10%; singlet, 13%±7%; negative control, 9%±5%; P<.05). These data have confirmed that the in situ administration of G, M, and T induces postinfarct ventricular functional improvement and that GMT polycistronic vectors enhance the efficacy of this strategy. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

An age-structured extension to the vectorial capacity model.

PubMed

Novoseltsev, Vasiliy N; Michalski, Anatoli I; Novoseltseva, Janna A; Yashin, Anatoliy I; Carey, James R; Ellis, Alicia M

2012-01-01

Vectorial capacity and the basic reproductive number (R(0)) have been instrumental in structuring thinking about vector-borne pathogen transmission and how best to prevent the diseases they cause. One of the more important simplifying assumptions of these models is age-independent vector mortality. A growing body of evidence indicates that insect vectors exhibit age-dependent mortality, which can have strong and varied affects on pathogen transmission dynamics and strategies for disease prevention. Based on survival analysis we derived new equations for vectorial capacity and R(0) that are valid for any pattern of age-dependent (or age-independent) vector mortality and explore the behavior of the models across various mortality patterns. The framework we present (1) lays the groundwork for an extension and refinement of the vectorial capacity paradigm by introducing an age-structured extension to the model, (2) encourages further research on the actuarial dynamics of vectors in particular and the relationship of vector mortality to pathogen transmission in general, and (3) provides a detailed quantitative basis for understanding the relative impact of reductions in vector longevity compared to other vector-borne disease prevention strategies. Accounting for age-dependent vector mortality in estimates of vectorial capacity and R(0) was most important when (1) vector densities are relatively low and the pattern of mortality can determine whether pathogen transmission will persist; i.e., determines whether R(0) is above or below 1, (2) vector population growth rate is relatively low and there are complex interactions between birth and death that differ fundamentally from birth-death relationships with age-independent mortality, and (3) the vector exhibits complex patterns of age-dependent mortality and R(0) ∼ 1. A limiting factor in the construction and evaluation of new age-dependent mortality models is the paucity of data characterizing vector mortality patterns, particularly for free ranging vectors in the field.

An Age-Structured Extension to the Vectorial Capacity Model

PubMed Central

Novoseltsev, Vasiliy N.; Michalski, Anatoli I.; Novoseltseva, Janna A.; Yashin, Anatoliy I.; Carey, James R.; Ellis, Alicia M.

2012-01-01

Background Vectorial capacity and the basic reproductive number (R0) have been instrumental in structuring thinking about vector-borne pathogen transmission and how best to prevent the diseases they cause. One of the more important simplifying assumptions of these models is age-independent vector mortality. A growing body of evidence indicates that insect vectors exhibit age-dependent mortality, which can have strong and varied affects on pathogen transmission dynamics and strategies for disease prevention. Methodology/Principal Findings Based on survival analysis we derived new equations for vectorial capacity and R0 that are valid for any pattern of age-dependent (or age–independent) vector mortality and explore the behavior of the models across various mortality patterns. The framework we present (1) lays the groundwork for an extension and refinement of the vectorial capacity paradigm by introducing an age-structured extension to the model, (2) encourages further research on the actuarial dynamics of vectors in particular and the relationship of vector mortality to pathogen transmission in general, and (3) provides a detailed quantitative basis for understanding the relative impact of reductions in vector longevity compared to other vector-borne disease prevention strategies. Conclusions/Significance Accounting for age-dependent vector mortality in estimates of vectorial capacity and R0 was most important when (1) vector densities are relatively low and the pattern of mortality can determine whether pathogen transmission will persist; i.e., determines whether R0 is above or below 1, (2) vector population growth rate is relatively low and there are complex interactions between birth and death that differ fundamentally from birth-death relationships with age-independent mortality, and (3) the vector exhibits complex patterns of age-dependent mortality and R0∼1. A limiting factor in the construction and evaluation of new age-dependent mortality models is the paucity of data characterizing vector mortality patterns, particularly for free ranging vectors in the field. PMID:22724022

Optimized Lentiviral Vector Design Improves Titer and Transgene Expression of Vectors Containing the Chicken β-Globin Locus HS4 Insulator Element

PubMed Central

Hanawa, Hideki; Yamamoto, Motoko; Zhao, Huifen; Shimada, Takashi; Persons, Derek A

2009-01-01

Hematopoietic cell gene therapy using retroviral vectors has achieved success in clinical trials. However, safety issues regarding vector insertional mutagenesis have emerged. In two different trials, vector insertion resulted in the transcriptional activation of proto-oncogenes. One strategy for potentially diminishing vector insertional mutagenesis is through the use of self-inactivating lentiviral vectors containing the 1.2-kb insulator element derived from the chicken β-globin locus. However, use of this element can dramatically decrease both vector titer and transgene expression, thereby compromising its practical use. Here, we studied lentiviral vectors containing either the full-length 1.2-kb insulator or the smaller 0.25-kb core element in both orientations in the partially deleted long-terminal repeat. We show that use of the 0.25-kb core insulator rescued vector titer by alleviating a postentry block to reverse transcription associated with the 1.2-kb element. In addition, in an orientation-dependent manner, the 0.25-kb core element significantly increased transgene expression from an internal promoter due to improved transcriptional termination. This element also demonstrated barrier activity, reducing variability of expression due to position effects. As it is known that the 0.25-kb core insulator has enhancer-blocking activity, this particular insulated lentiviral vector design may be useful for clinical application. PMID:19223867

An improved ternary vector system for Agrobacterium-mediated rapid maize transformation.

PubMed

Anand, Ajith; Bass, Steven H; Wu, Emily; Wang, Ning; McBride, Kevin E; Annaluru, Narayana; Miller, Michael; Hua, Mo; Jones, Todd J

2018-05-01

A simple and versatile ternary vector system that utilizes improved accessory plasmids for rapid maize transformation is described. This system facilitates high-throughput vector construction and plant transformation. The super binary plasmid pSB1 is a mainstay of maize transformation. However, the large size of the base vector makes it challenging to clone, the process of co-integration is cumbersome and inefficient, and some Agrobacterium strains are known to give rise to spontaneous mutants resistant to tetracycline. These limitations present substantial barriers to high throughput vector construction. Here we describe a smaller, simpler and versatile ternary vector system for maize transformation that utilizes improved accessory plasmids requiring no co-integration step. In addition, the newly described accessory plasmids have restored virulence genes found to be defective in pSB1, as well as added virulence genes. Testing of different configurations of the accessory plasmids in combination with T-DNA binary vector as ternary vectors nearly doubles both the raw transformation frequency and the number of transformation events of usable quality in difficult-to-transform maize inbreds. The newly described ternary vectors enabled the development of a rapid maize transformation method for elite inbreds. This vector system facilitated screening different origins of replication on the accessory plasmid and T-DNA vector, and four combinations were identified that have high (86-103%) raw transformation frequency in an elite maize inbred.