Lysophosphatidic acid signaling through its receptor initiates profibrotic epithelial cell fibroblast communication mediated by epithelial cell derived connective tissue growth factor.

Science.gov (United States)

Sakai, Norihiko; Chun, Jerold; Duffield, Jeremy S; Lagares, David; Wada, Takashi; Luster, Andrew D; Tager, Andrew M

2017-03-01

The expansion of the fibroblast pool is a critical step in organ fibrosis, but the mechanisms driving expansion remain to be fully clarified. We previously showed that lysophosphatidic acid (LPA) signaling through its receptor LPA 1 expressed on fibroblasts directly induces the recruitment of these cells. Here we tested whether LPA-LPA 1 signaling drives fibroblast proliferation and activation during the development of renal fibrosis. LPA 1 -deficient (LPA 1 -/- ) or -sufficient (LPA 1 +/+ ) mice were crossed to mice with green fluorescent protein expression (GFP) driven by the type I procollagen promoter (Col-GFP) to identify fibroblasts. Unilateral ureteral obstruction-induced increases in renal collagen were significantly, though not completely, attenuated in LPA 1 -/- Col-GFP mice, as were the accumulations of both fibroblasts and myofibroblasts. Connective tissue growth factor was detected mainly in tubular epithelial cells, and its levels were suppressed in LPA 1 -/- Col-GFP mice. LPA-LPA 1 signaling directly induced connective tissue growth factor expression in primary proximal tubular epithelial cells, through a myocardin-related transcription factor-serum response factor pathway. Proximal tubular epithelial cell-derived connective tissue growth factor mediated renal fibroblast proliferation and myofibroblast differentiation. Administration of an inhibitor of myocardin-related transcription factor/serum response factor suppressed obstruction-induced renal fibrosis. Thus, targeting LPA-LPA 1 signaling and/or myocardin-related transcription factor/serum response factor-induced transcription could be promising therapeutic strategies for renal fibrosis. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Effective factors in expansion of medical tourism in Iran

Science.gov (United States)

Rezaee, Reza; Mohammadzadeh, Mehdi

2016-01-01

Background: Medical tourism (MT) refers to circumstances in which people travel for medical treatments. The present study focuses on determining factors affecting MT in Iran. Methods: The study uses a mixed method approach. Initially, through a qualitative study, 12 experts were interviewed deeply; then, 22 participants in three equal focus groups expressed their ideas about growth and development of MT in Iran. Based on the expressed ideas, 120 factors were identified and accordingly a structured questionnaire was developed. Some members from the focus groups confirmed the questionnaire’s face and content validity. The reliability of pertinent items was confirmed using Cronbach’s alpha=0.8. Afterwards, 61 eligible subjects filled out this questionnaire. Results: The findings showed that "healthcare quality" and "high level of expertise" are two most attractive factors in MT. However, other factors such as "healthcare costs", and "visa facilities" are among key factors as well. Also, the role of "the healthcare providers" was found to be more prominent than the roles of "the government" and "the general tourist services". Conclusion: Although some attractive MT factors are present currently, MT expansion to a desirable level in Iran requires a comprehensive plan of which its factors were discussed in this paper. PMID:27683650

A novel monoclonal antibody of human stem cell factor inhibits umbilical cord blood stem cell ex vivo expansion

Directory of Open Access Journals (Sweden)

Fan Jie

2012-12-01

Full Text Available Abstract Stem cell factor (SCF activates hematopoietic stem cell (HSC self-renewal and is being used to stimulate the ex vivo expansion of HSCs. The mechanism by which SCF supports expansion of HSCs remains poorly understood. In cord blood ex vivo expansion assays, a newly produced anti-SCF monoclonal antibody (clone 23C8 was found to significantly inhibit the expansion of CD34+ cells. This antibody appears to bind directly to a part of SCF that is critical for biological activity toward expansion of CD34+ cells, which is located in the first 104 amino acids from the NH2-terminus.

Host and Viral Factors in HIV-Mediated Bystander Apoptosis

Science.gov (United States)

Garg, Himanshu; Joshi, Anjali

2017-01-01

Human immunodeficiency virus (HIV) infections lead to a progressive loss of CD4 T cells primarily via the process of apoptosis. With a limited number of infected cells and vastly disproportionate apoptosis in HIV infected patients, it is believed that apoptosis of uninfected bystander cells plays a significant role in this process. Disease progression in HIV infected individuals is highly variable suggesting that both host and viral factors may influence HIV mediated apoptosis. Amongst the viral factors, the role of Envelope (Env) glycoprotein in bystander apoptosis is well documented. Recent evidence on the variability in apoptosis induction by primary patient derived Envs underscores the role of Env glycoprotein in HIV disease. Amongst the host factors, the role of C-C Chemokine Receptor type 5 (CCR5), a coreceptor for HIV Env, is also becoming increasingly evident. Polymorphisms in the CCR5 gene and promoter affect CCR5 cell surface expression and correlate with both apoptosis and CD4 loss. Finally, chronic immune activation in HIV infections induces multiple defects in the immune system and has recently been shown to accelerate HIV Env mediated CD4 apoptosis. Consequently, those factors that affect CCR5 expression and/or immune activation in turn indirectly regulate HIV mediated apoptosis making this phenomenon both complex and multifactorial. This review explores the complex role of various host and viral factors in determining HIV mediated bystander apoptosis. PMID:28829402

The mediating effect of psychosocial factors on suicidal probability among adolescents.

Science.gov (United States)

Hur, Ji-Won; Kim, Won-Joong; Kim, Yong-Ku

2011-01-01

Suicidal probability is an actual tendency including negative self-evaluation, hopelessness, suicidal ideation, and hostility. The purpose of this study was to examine the role of psychosocial variances in the suicidal probability of adolescents, especially the role of mediating variance. This study investigated the mediating effects of psychosocial factors such as depression, anxiety, self-esteem, stress, and social support on the suicidal probability among 1,586 adolescents attending middle and high schools in the Kyunggi Province area of South Korea. The relationship between depression and anxiety/suicidal probability was mediated by both social resources and self-esteem. Furthermore, the influence of social resources was mediated by interpersonal and achievement stress as well as self-esteem. This study suggests that suicidal probability in adolescents has various relationships, including mediating relations, with several psychosocial factors. The interventions on suicidal probability in adolescents should focus on social factors as well as clinical symptoms.

The Mediator complex and transcription regulation

Science.gov (United States)

Poss, Zachary C.; Ebmeier, Christopher C.

2013-01-01

The Mediator complex is a multi-subunit assembly that appears to be required for regulating expression of most RNA polymerase II (pol II) transcripts, which include protein-coding and most non-coding RNA genes. Mediator and pol II function within the pre-initiation complex (PIC), which consists of Mediator, pol II, TFIIA, TFIIB, TFIID, TFIIE, TFIIF and TFIIH and is approximately 4.0 MDa in size. Mediator serves as a central scaffold within the PIC and helps regulate pol II activity in ways that remain poorly understood. Mediator is also generally targeted by sequence-specific, DNA-binding transcription factors (TFs) that work to control gene expression programs in response to developmental or environmental cues. At a basic level, Mediator functions by relaying signals from TFs directly to the pol II enzyme, thereby facilitating TF-dependent regulation of gene expression. Thus, Mediator is essential for converting biological inputs (communicated by TFs) to physiological responses (via changes in gene expression). In this review, we summarize an expansive body of research on the Mediator complex, with an emphasis on yeast and mammalian complexes. We focus on the basics that underlie Mediator function, such as its structure and subunit composition, and describe its broad regulatory influence on gene expression, ranging from chromatin architecture to transcription initiation and elongation, to mRNA processing. We also describe factors that influence Mediator structure and activity, including TFs, non-coding RNAs and the CDK8 module. PMID:24088064

Insulin-like growth factor 1: common mediator of multiple enterotrophic hormones and growth factors.

Science.gov (United States)

Bortvedt, Sarah F; Lund, P Kay

2012-03-01

To summarize the recent evidence that insulin-like growth factor 1 (IGF1) mediates growth effects of multiple trophic factors and discuss clinical relevance. Recent reviews and original reports indicate benefits of growth hormone (GH) and long-acting glucagon-like peptide 2 (GLP2) analogs in short bowel syndrome and Crohn's disease. This review highlights the evidence that biomarkers of sustained small intestinal growth or mucosal healing and evaluation of intestinal epithelial stem cell biomarkers may improve clinical measures of intestinal growth or response to trophic hormones. Compelling evidence that IGF1 mediates growth effects of GH and GLP2 on intestine or linear growth in preclinical models of resection or Crohn's disease is presented, along with a concept that these hormones or IGF1 may enhance sustained growth if given early after bowel resection. Evidence that suppressor of cytokine signaling protein induction by GH or GLP2 in normal or inflamed intestine may limit IGF1-induced growth, but protect against risk of dysplasia or fibrosis, is reviewed. Whether IGF1 receptor mediates IGF1 action and potential roles of insulin receptors are addressed. IGF1 has a central role in mediating trophic hormone action in small intestine. Better understanding of benefits and risks of IGF1, receptors that mediate IGF1 action, and factors that limit undesirable growth are needed.

Factorization of differential expansion for antiparallel double-braid knots

Science.gov (United States)

Morozov, A.

2016-09-01

Continuing the quest for exclusive Racah matrices, which are needed for evaluation of colored arborescent-knot polynomials in Chern-Simons theory, we suggest to extract them from a new kind of a double-evolution — that of the antiparallel double-braids, which is a simple two-parametric family of two-bridge knots, generalizing the one-parametric family of twist knots. In the case of rectangular representations R = [ r s ] we found an evidence that the corresponding differential expansion miraculously factorizes and can be obtained from that for the twist knots. This reduces the problem of rectangular exclusive Racah to constructing the answers for just a few twist knots. We develop a recent conjecture on the structure of differential expansion for the simplest members of this family (the trefoil and the figure-eight knot) and provide the exhaustive answer for the first unknown case of R = [33]. The answer includes HOMFLY of arbitrary twist and double-braid knots and Racah matrices overline{S} and S — what allows to calculate [33]-colored polynomials for arbitrary arborescent (double-fat) knots. For generic rectangular representations fully described are only the contributions of the single-floor pyramids. One step still remains to be done.

Coordinate expansion of murine hematopoietic and mesenchymal stem cell compartments by SHIPi.

Science.gov (United States)

Brooks, R; Iyer, S; Akada, H; Neelam, S; Russo, C M; Chisholm, J D; Kerr, W G

2015-03-01

Promoting the expansion of adult stem cell populations offers the potential to ameliorate radiation or chemotherapy-induced bone marrow failure and allows for expedited recovery for patients undergoing these therapies. Previous genetic studies suggested a pivotal role for SH2 domain-containing inositol-5-phosphatase 1 (SHIP1) in limiting the size of the hematopoietic stem cell (HSC) compartment. The aim of this study was to determine whether our recent development of small molecule SHIP1 inhibitors offers the potential for pharmacological expansion of the HSC compartment in vivo. We show here that treatment of mice with aminosteroid inhibitors of SHIP1 (SHIPi) more than doubles the size of the adult mesenchymal stem cell (MSC) compartment while simultaneously expanding the HSC pool sixfold. Consistent with its ability to target SHIP1 function in vivo, SHIPi also significantly increases plasma granulocyte colony-stimulating factor (G-CSF) levels, a growth factor that supports proliferation of HSC. Here, we show that SHIPi-induced G-CSF production mediates HSC and MSC expansion, as in vivo neutralization of G-CSF abrogates the SHIPi-induced expansion of both the HSC and MSC compartments. Due to its expansionary effect on adult stem cell compartments, SHIPi represents a potential novel strategy to improve declining stem cell function in both therapy induced and genetically derived bone marrow failure syndromes. © 2014 AlphaMed Press.

A Defective mRNA Cleavage and Polyadenylation Complex Facilitates Expansions of Transcribed (GAAn Repeats Associated with Friedreich’s Ataxia

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Ryan J. McGinty

2017-09-01

Full Text Available Expansions of microsatellite repeats are responsible for numerous hereditary diseases in humans, including myotonic dystrophy and Friedreich’s ataxia. Whereas the length of an expandable repeat is the main factor determining disease inheritance, recent data point to genomic trans modifiers that can impact the likelihood of expansions and disease progression. Detection of these modifiers may lead to understanding and treating repeat expansion diseases. Here, we describe a method for the rapid, genome-wide identification of trans modifiers for repeat expansion in a yeast experimental system. Using this method, we found that missense mutations in the endoribonuclease subunit (Ysh1 of the mRNA cleavage and polyadenylation complex dramatically increase the rate of (GAAn repeat expansions but only when they are actively transcribed. These expansions correlate with slower transcription elongation caused by the ysh1 mutation. These results reveal an interplay between RNA processing and repeat-mediated genome instability, confirming the validity of our approach.

Influence of patient related factors on number of mesenchymal stromal cells reached after in vitro culture expansion for clinical treatment

DEFF Research Database (Denmark)

Qayyum, Abbas Ali; Kaur, Kamal Preet; Mathiasen, Anders Bruun

2017-01-01

of autologous stromal cells reached after in vitro culture expansion for clinical therapy. METHODS: Culture expansion data from 111 patients with IHD treated with autologous stromal cells in three clinical trials were used. We correlated the final cell count after two passages of cultivation with different...... correlation between left ventricular ejection fraction and number of MSCs was found (r = -0.287, p = .017). CONCLUSIONS: Patient related factors such as BMI, hypertension and gender may influence the number of MSCs reached after in vitro culture expansion....... patient factors. RESULTS: There was a significant relation between body mass index (BMI) and the number of adipose derived stromal cells (ASCs) reached after culture expansion and for all patients included into the three studies (r = 0.375, p = .019 and r = 0.200, p = .036, respectively). Moreover...

Uncertainty Evaluation of the Thermal Expansion of Gd2O3-ZrO2 with a System Calibration Factor

International Nuclear Information System (INIS)

Park, Chang Je; Kang, Kweon Ho; Na, Sang Ho; Song, Kee Chan

2007-01-01

Both gadolinia (Gd 2 O 3 ) and zirconia (ZrO 2 ) are widely used in the nuclear industry, including a burnable absorber and additives in the fabrication of a simulated fuel. Thermal expansions of a mixture of gadolinia (Gd 2 O 3 ) 20 mol% and zirconia (ZrO 2 ) 80 mol% were measured by using a dilatometer (DIL402C) from room temperature to 1500 .deg. C. Uncertainties in the measurement should be quantified based on statistics. Referring to the ISO (International Organization for Standardization) guide, the uncertainties of the thermal expansion were quantified for three parts - the initial length, the length variation, and the system calibration factor. The whole system, the dilatometer, is composed of many complex sub-systems and in fact it is difficult to consider all the uncertainties of the sub-systems. Thus, the system calibration factor was introduced with a standard material for the uncertainty evaluation. In this study, a new system calibration factor was formulated in a multiplicative way. Further, the effect of calibration factor with random deviation was investigated for the uncertainty evaluation of a thermal expansion

Multiple pathways of commodity crop expansion in tropical forest landscapes

Science.gov (United States)

Meyfroidt, Patrick; Carlson, Kimberly M.; Fagan, Matthew E.; Gutiérrez-Vélez, Victor H.; Macedo, Marcia N.; Curran, Lisa M.; DeFries, Ruth S.; Dyer, George A.; Gibbs, Holly K.; Lambin, Eric F.; Morton, Douglas C.; Robiglio, Valentina

2014-07-01

Commodity crop expansion, for both global and domestic urban markets, follows multiple land change pathways entailing direct and indirect deforestation, and results in various social and environmental impacts. Here we compare six published case studies of rapid commodity crop expansion within forested tropical regions. Across cases, between 1.7% and 89.5% of new commodity cropland was sourced from forestlands. Four main factors controlled pathways of commodity crop expansion: (i) the availability of suitable forestland, which is determined by forest area, agroecological or accessibility constraints, and land use policies, (ii) economic and technical characteristics of agricultural systems, (iii) differences in constraints and strategies between small-scale and large-scale actors, and (iv) variable costs and benefits of forest clearing. When remaining forests were unsuitable for agriculture and/or policies restricted forest encroachment, a larger share of commodity crop expansion occurred by conversion of existing agricultural lands, and land use displacement was smaller. Expansion strategies of large-scale actors emerge from context-specific balances between the search for suitable lands; transaction costs or conflicts associated with expanding into forests or other state-owned lands versus smallholder lands; net benefits of forest clearing; and greater access to infrastructure in already-cleared lands. We propose five hypotheses to be tested in further studies: (i) land availability mediates expansion pathways and the likelihood that land use is displaced to distant, rather than to local places; (ii) use of already-cleared lands is favored when commodity crops require access to infrastructure; (iii) in proportion to total agricultural expansion, large-scale actors generate more clearing of mature forests than smallholders; (iv) property rights and land tenure security influence the actors participating in commodity crop expansion, the form of land use displacement

Multiple pathways of commodity crop expansion in tropical forest landscapes

International Nuclear Information System (INIS)

Meyfroidt, Patrick; Lambin, Eric F; Carlson, Kimberly M; Fagan, Matthew E; DeFries, Ruth S; Gutiérrez-Vélez, Victor H; Macedo, Marcia N; Curran, Lisa M; Dyer, George A; Gibbs, Holly K; Morton, Douglas C; Robiglio, Valentina

2014-01-01

Commodity crop expansion, for both global and domestic urban markets, follows multiple land change pathways entailing direct and indirect deforestation, and results in various social and environmental impacts. Here we compare six published case studies of rapid commodity crop expansion within forested tropical regions. Across cases, between 1.7% and 89.5% of new commodity cropland was sourced from forestlands. Four main factors controlled pathways of commodity crop expansion: (i) the availability of suitable forestland, which is determined by forest area, agroecological or accessibility constraints, and land use policies, (ii) economic and technical characteristics of agricultural systems, (iii) differences in constraints and strategies between small-scale and large-scale actors, and (iv) variable costs and benefits of forest clearing. When remaining forests were unsuitable for agriculture and/or policies restricted forest encroachment, a larger share of commodity crop expansion occurred by conversion of existing agricultural lands, and land use displacement was smaller. Expansion strategies of large-scale actors emerge from context-specific balances between the search for suitable lands; transaction costs or conflicts associated with expanding into forests or other state-owned lands versus smallholder lands; net benefits of forest clearing; and greater access to infrastructure in already-cleared lands. We propose five hypotheses to be tested in further studies: (i) land availability mediates expansion pathways and the likelihood that land use is displaced to distant, rather than to local places; (ii) use of already-cleared lands is favored when commodity crops require access to infrastructure; (iii) in proportion to total agricultural expansion, large-scale actors generate more clearing of mature forests than smallholders; (iv) property rights and land tenure security influence the actors participating in commodity crop expansion, the form of land use displacement

Stat6 Promotes Intestinal Tumorigenesis in a Mouse Model of Adenomatous Polyposis by Expansion of MDSCs and Inhibition of Cytotoxic CD8 Response.

Science.gov (United States)

Jayakumar, Asha; Bothwell, Alfred L M

2017-08-01

Intestinal tumorigenesis in the ApcMin/+ model is initiated by aberrant activation of Wnt pathway. Increased IL-4 expression in human colorectal cancer tissue and growth of colon cancer cell lines implied that IL-4-induced Stat6-mediated tumorigenic signaling likely contributes to intestinal tumor progression in ApcMin/+ mice. Stat6 also appears to promote expansion of myeloid-derived suppressor cells (MDSCs) cells. MDSCs promote polyp formation in the ApcMin/+ model. Hence, Stat6 could have a broad role in coordinating both polyp cell proliferation and MDSC expansion. We found that IL-4-induced Stat6-mediated proliferation of intestinal epithelial cells is augmented by platelet-derived growth factor-BB, a tumor-promoting growth factor. To determine whether polyp progression in ApcMin/+ mice is dependent on Stat6 signaling, we disrupted Stat6 in this model. Total polyps in the small intestine were fewer in ApcMin/+ mice lacking Stat6. Furthermore, proliferation of polyp epithelial cells was reduced, indicating that Stat6 in part controlled polyp formation. Stat6 also promoted expansion of MDSCs in the spleen and lamina propria of ApcMin/+ mice, implying regulation of antitumor T-cell response. More CD8 cells and reduced PD-1 expression on CD4 cells correlated with reduced polyps. In addition, a strong CD8-mediated cytotoxic response led to killing of tumor cells in Stat6-deficient ApcMin/+ mice. Therefore, these findings show that Stat6 has an oncogenic role in intestinal tumorigenesis by promoting polyp cell proliferation and immunosuppressive mediators, and preventing an active cytotoxic process. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Molecular analysis of expansion, differentiation, and growth factor treatment of human chondrocytes identifies differentiation markers and growth-related genes.

Science.gov (United States)

Benz, Karin; Breit, Stephen; Lukoschek, Martin; Mau, Hans; Richter, Wiltrud

2002-04-26

This study is intended to optimise expansion and differentiation of cultured human chondrocytes by growth factor application and to identify molecular markers to monitor their differentiation state. We dissected the molecular consequences of matrix release, monolayer, and 3D-alginate culture, growth factor optimised expansion, and re-differentiation protocols by gene expression analysis. Among 19 common cartilage molecules assessed by cDNA array, six proved best to monitor differentiation. Instant down-regulation at release of cells from the matrix was strongest for COL 2A1, fibromodulin, and PRELP while LUM, CHI3L1, and CHI3L2 were expansion-related. Both gene sets reflected the physiologic effects of the most potent growth-inducing (PDGF-BB) and proteoglycan-inducing (BMP-4) factors. Only CRTAC1 expression correlated with 2D/3D switches while the molecular phenotype of native chondrocytes was not restored. The markers and optimised protocols we suggest can help to improve cell therapy of cartilage defects and chondrocyte differentiation from stem cell sources.

Foreign Direct Investments Expansion – Essential Globalization Factor

Directory of Open Access Journals (Sweden)

Cătălin Emilian HUIDUMAC PETRESCU

2011-01-01

Full Text Available We live in a time when the world economy is constantly changing. Foreign direct investments is one of the most dynamic part of the world economy and in a continuous globalization, those international financial flows determining the traders to know their defining elements and to adopt a specific management in the international affairs field. We are viewers of an unprecedented expansion of foreign direct investments, essential factor of the globalization development process. The paper analyzes the evolution of FDI so far, along with a brief illustration as the main trends of international financial flows for 2010 and 2011. In the context of economic globalization, it is absolutely necessary to clear out a study on the various economic activities, especially on the differences between countries. The analysis of these differences is particularly important as it helps improve and optimize the strategies adopted by foreign transnational companies. In the past 15 years, one observes that most companies in emerging countries, characterized by a great expansion, have adopted in the first phase of their existence, corporate strategies that gave them the opportunity to become global companies. According to surveys, after reaching the first goal, becoming a multinational or a transnational company, they have developed new business models beyond the classical principles and strategies. It is anticipated that in the coming decades, the strategies of emerging companies will be influenced by functional specialization, which, according to experts, influence the process of globalization. The analysis of strategies adopted by companies in emerging countries is absolutely necessary because the results cannot be overlooked. For example, until 2004, only five Asian companies were part of the top 100 transnational companies. The study was carried out by UNCTAD and the identification criterion was the size of foreign assets. In 2006, 14% of world total FDI came from

Use of fibroblast growth factor 2 for expansion of chondrocytes and tissue engineering

Science.gov (United States)

Vunjak-Novakovic, Gordana (Inventor); Martin, Ivan (Inventor); Freed, Lisa E. (Inventor); Langer, Robert (Inventor)

2003-01-01

The present invention provides an improved method for expanding cells for use in tissue engineering. In particular the method provides specific biochemical factors to supplement cell culture medium during the expansion process in order to reproduce events occurring during embryonic development with the goal of regenerating tissue equivalents that resemble natural tissues both structurally and functionally. These specific biochemical factors improve proliferation of the cells and are capable of de-differentiation mature cells isolated from tissue so that the differentiation potential of the cells is preserved. The bioactive molecules also maintain the responsiveness of the cells to other bioactive molecules. Specifically, the invention provides methods for expanding chondrocytes in the presence of fibroblast growth factor 2 for use in regeneration of cartilage tissue.

INTEGRAL INDICATORS OF THE INFLUENCE OF FORMULATECHNOLOGICAL FACTORS ON THE CEMENT MATRIX OF CONCRETE STRUCTURE FORMATION FOR INJECTION WITH TWO-STEP EXPANSION

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T. N. Zhilnikova

2016-01-01

Full Text Available Objectives. The formation of the structure of hardened concrete grouting with two-stage expansion is a complex process that is influenced by many factors, both of a prescriptive nature (composition and additive dosage, mineralogical composition of Portland cement clinker, concrete composition, the presence of chemical additives and in terms of process (the fineness of cement grinding, temperature of curing, etc.. Methods. In order to assess the impact of the above factors, the article proposes the introduction of a number of integrated indicators being characterised as a process in which influences are shown alongside the factor generating the influence. For the evaluation of the influence of different factors on the process of gas generation, an effectiveness ratio of gas generation is proposed by the authors. Results. The article presents the results of an investigation into the influence of the amount of gassing agent and the type and dosage of superplasticiser on the process of gassing by means of the displacement method on the mortar mix. The authors similarly propose a expansion efficiency coefficient. The article presents the results of the investigation into the influence of the amount of gassing agent, the presence and amount of superplasticiser, the sand/cement ratio, aggregate size and water-cement ratio during the first stage of expansion of the mixture. The authors propose a formula for describing the dependence of the relative expansion deformations on the concentration of filler. In order to assess the conditions in which a mixture is present, it is proposed to use an indicator consisting in the constraint expansion coefficient. Conclusion. Use of the hardening condition coefficient is proposed as a means of accounting for the effect of curing conditions on the strength of the concrete grouting with two-stage expansion. The authors recommend taking the introduction of correction factors into account when considering the impact of

Risk Factors for Preschool Depression: The Mediating Role of Early Stressful Life Events

Science.gov (United States)

Luby, Joan L.; Belden, Andy C.; Spitznagel, Edward

2006-01-01

Background: Family history of mood disorders and stressful life events are both established risk factors for childhood depression. However, the role of mediators in risk trajectories, which are potential targets for intervention, remains understudied. To date, there have been no investigations of mediating relationships between risk factors and…

Effect of intraovarian factors on porcine follicular cells: cumulus expansion, granulosa and cumulus cell progesterone production

Czech Academy of Sciences Publication Activity Database

Ježová, M.; Scsuková, S.; Nagyová, Eva; Vranová, J.; Procházka, Radek; Kolena, J.

2001-01-01

Roč. 65, - (2001), s. 115-126 ISSN 0378-4320 R&D Projects: GA ČR GA524/98/0231; GA AV ČR KSK5052113 Keywords : pig-ovary * cumulus expansion * luteinization stimulator Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.196, year: 2001

Gender difference in sickness absence from work: a multiple mediation analysis of psychosocial factors.

Science.gov (United States)

Casini, Annalisa; Godin, Isabelle; Clays, Els; Kittel, France

2013-08-01

Previous research has shown that job characteristics, private life and psychosocial factors partially account for gender difference in work absences because of sickness. Most studies have analysed these factors separately. The aim of the present study was to evaluate whether these explanatory factors act as mediators when they are considered simultaneously. The evaluated data set comprises the merger of two Belgian longitudinal studies, BELSTRESS III and SOMSTRESS. It includes 3821 workers (1541 men) aged 21-66 years, employed in eight organizations. A multiple mediation analysis was performed to explain the higher prevalence among women. Estimated factors were occupational grade, total number of paid working hours per week, job strain, overcommitment, home-work interference and social support at and outside work. Prospective data concerning duration and frequency of medically justified sickness absence (registered by the organizations) were used as outcomes. Overall, the mediating factors partially account for gender difference in sickness absence. The strongest mediator for both outcomes is job strain. In addition, difference in absence duration is mediated by social support at work, whereas difference in frequency is mediated by professional grade and home-work interference. Our results call attention to the necessity to elaborate actual preventive actions aiming at favouring a better positioning of women on the labour market in term of hierarchical level as well as in terms of quality of work for reducing sickness absence in this group.

Hypoxia-inducible factor-dependent production of profibrotic mediators by hypoxic hepatocytes.

Science.gov (United States)

Copple, Bryan L; Bustamante, Juan J; Welch, Timothy P; Kim, Nam Deuk; Moon, Jeon-Ok

2009-08-01

During the development of liver fibrosis, mediators are produced that stimulate cells in the liver to differentiate into myofibroblasts and to produce collagen. Recent studies demonstrated that the transcription factor, hypoxia-inducible factor-1alpha (HIF-1alpha), is critical for upregulation of profibrotic mediators, such as platelet-derived growth factor-A (PDGF-A), PDGF-B and plasminogen activator inhibitor-1 (PAI-1) in the liver, during the development of fibrosis. What remains unknown is the cell type-specific regulation of these genes by HIF-1alpha in liver cell types. Accordingly, the hypothesis was tested that HIF-1alpha is activated in hypoxic hepatocytes and regulates the production of profibrotic mediators by these cells. In this study, hepatocytes were isolated from the livers of control and HIF-1alpha- or HIF-1beta-deficient mice and exposed to hypoxia. Exposure of primary mouse hepatocytes to 1% oxygen stimulated nuclear accumulation of HIF-1alpha and upregulated PAI-1, vascular endothelial cell growth factor and the vasoactive peptides adrenomedullin-1 (ADM-1) and ADM-2. In contrast, the levels of PDGF-A and PDGF-B mRNAs were unaffected in these cells by hypoxia. Exposure of HIF-1alpha-deficient hepatocytes to 1% oxygen only partially prevented upregulation of these genes, suggesting that other hypoxia-regulated transcription factors, such as HIF-2alpha, may also regulate these genes. In support of this, HIF-2alpha was activated in hypoxic hepatocytes, and exposure of HIF-1beta-deficient hepatocytes to 1% oxygen completely prevented upregulation of PAI-1, vascular endothelial cell growth factor and ADM-1, suggesting that HIF-2alpha may also contribute to upregulation of these genes in hypoxic hepatocytes. Collectively, our results suggest that HIFs may be important regulators of profibrotic and vasoactive mediators by hypoxic hepatocytes.

Hematoma Expansion Following Acute Intracerebral Hemorrhage

Science.gov (United States)

Brouwers, H. Bart; Greenberg, Steven M.

2013-01-01

Intracerebral hemorrhage, the most devastating form of stroke, has no specific therapy proven to improve outcome by randomized controlled trial. Location and baseline hematoma volume are strong predictors of mortality, but are non-modifiable by the time of diagnosis. Expansion of the initial hematoma is a further marker of poor prognosis that may be at least partly preventable. Several risk factors for hematoma expansion have been identified, including baseline ICH volume, early presentation after symptom onset, anticoagulation, and the CT angiography spot sign. Although the biological mechanisms of hematoma expansion remain unclear, accumulating evidence supports a model of ongoing secondary bleeding from ruptured adjacent vessels surrounding the initial bleeding site. Several large clinical trials testing therapies aimed at preventing hematoma expansion are in progress, including aggressive blood pressure reduction, treatment with recombinant factor VIIa guided by CT angiography findings, and surgical intervention for superficial hematomas without intraventricular extension. Hematoma expansion is so far the only marker of outcome that is amenable to treatment and thus a potentially important therapeutic target. PMID:23466430

IMPACT OF FORMULA-TECHNOLOGICAL FACTORS ON CONCRETE STRENGTH INDICATORS FOR INJECTING WITH TWO-STAGE EXPANSION

Directory of Open Access Journals (Sweden)

Tatjana N. Zhilnikova

2017-01-01

Full Text Available Abstract. Objectives The aim of the study is to clarify the dependence of the cement stone strength on additional porosity that is formed owing both to the cement stone’s development of free deformations and the expansion of the hardening concrete in the second stage as caused by the action of the expanding additive. Method The study is based on the introduction of a sulphoaluminate-type expanding additive in the composition of a binder based on alumina cement, natural gypsum stone and nitrilotrimethylphosphonic acid. Results It is shown that an important role is played in the technology of expanding concrete not only by the degree of expansion of the cement stone, but also by its strength, both during the development of deformations and following stabilisation. Among factors influencing the kinetics of hardening are not only recipe-related (composition and dosage of the additive, mineralogical composition of Portland cement clinker, composition of the concrete, presence of chemical additives, but also technological (fineness of cement grinding, hardening temperature, etc. that makes the management of the processes of structure formation quite complex. The dependence of the strength of cement stone on the additional porosity formed due to the growth of the cement stone own free deformations and expansion of the hardening concrete in the second stage due to the action of the expanding additive is revealed; dependence of the influence of kinetics of the structure formation regulator - nitrilotrimethylphosphonic acid - on the consistency of the development of the intrinsic free expansion deformations and the formation of the strength of the cement stone in the second stage; the dependence of the strength of the cement stone on the additional porosity formed due to gas evolution and expansion of the mixture in the first stage due to the action of the gas-forming additive; the influence of the constraint of expansion on the formation of the

Mediating factors of coping process in parents of children with type 1 diabetes.

Science.gov (United States)

Oskouie, Fatemeh; Mehrdad, Neda; Ebrahimi, Hossein

2013-05-14

Type 1 diabetes is a lifelong condition for children and their parents, the management for which imposes a vast responsibility. This study explores the mediating factors that affect Iranian parents' coping processes with their children's type 1 diabetes. Research was conducted using the grounded theory method. Participants were selected purposefully, and we continued with theoretical sampling. Constant comparative analysis was used to analyze the data. The mediating factors of the parental coping process with their child's diabetes consist of the child's cooperation, crises and experiences, economic challenges, and parental participation in care. Findings highlight the necessity of well-informed nurses with insightful understanding of the mediating factors in parental coping with juvenile diabetes in order to meet the particular needs of this group.

On the area expansion of magnetic flux tubes in solar active regions

Energy Technology Data Exchange (ETDEWEB)

Dudík, Jaroslav [DAMTP, CMS, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Dzifčáková, Elena [Astronomical Institute of the Academy of Sciences of the Czech Republic, Fričova 298, 251 65 Ondřejov (Czech Republic); Cirtain, Jonathan W., E-mail: J.Dudik@damtp.cam.ac.uk, E-mail: elena@asu.cas.cz [NASA Marshall Space Flight Center, VP 62, Huntsville, AL 35812 (United States)

2014-11-20

We calculated the three-dimensional (3D) distribution of the area expansion factors in a potential magnetic field, extrapolated from the high-resolution Hinode/SOT magnetogram of the quiescent active region NOAA 11482. Retaining only closed loops within the computational box, we show that the distribution of area expansion factors show significant structure. Loop-like structures characterized by locally lower values of the expansion factor are embedded in a smooth background. These loop-like flux tubes have squashed cross-sections and expand with height. The distribution of the expansion factors show an overall increase with height, allowing an active region core characterized by low values of the expansion factor to be distinguished. The area expansion factors obtained from extrapolation of the Solar Optical Telescope magnetogram are compared to those obtained from an approximation of the observed magnetogram by a series of 134 submerged charges. This approximation retains the general flux distribution in the observed magnetogram, but removes the small-scale structure in both the approximated magnetogram and the 3D distribution of the area expansion factors. We argue that the structuring of the expansion factor can be a significant ingredient in producing the observed structuring of the solar corona. However, due to the potential approximation used, these results may not be applicable to loops exhibiting twist or to active regions producing significant flares.

The psychological aftermath of bereavement : Risk factors, mediating processes, and intervention

NARCIS (Netherlands)

Van der Houwen, H.K.

2009-01-01

In this dissertation some of the major facets associated with the psychological effects of bereavement were the subject of investigation: risk factors, mediating processes and intervention. Previous research on risk factors is limited because of a number of methodological shortcomings: a focus on

Effect of Fibroblast Growth Factor 2 on Equine Synovial Fluid Chondroprogenitor Expansion and Chondrogenesis

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Marta Bianchessi

2016-01-01

Full Text Available Mesenchymal stem cells have been identified in the synovial fluid of several species. This study was conducted to characterize chondroprogenitor (CP cells in equine synovial fluid (SF and to determine the effect of fibroblast growth factor 2 (FGF-2 on SF-CP monolayer proliferation and subsequent chondrogenesis. We hypothesized that FGF-2 would stimulate SF-CP proliferation and postexpansion chondrogenesis. SF aspirates were collected from adult equine joints. Colony-forming unit (CFU assays were performed during primary cultures. At first passage, SF-cells were seeded at low density, with or without FGF-2. Following monolayer expansion and serial immunophenotyping, cells were transferred to chondrogenic pellet cultures. Pellets were analyzed for chondrogenic mRNA expression and cartilage matrix secretion. There was a mean of 59.2 CFU/mL of SF. FGF-2 increased the number of population doublings during two monolayer passages and halved the population doubling times. FGF-2 did not alter the immunophenotype of SF-CPs during monolayer expansion, nor did FGF-2 compromise chondrogenesis. Hypertrophic phenotypic markers were not expressed in control or FGF-2 groups. FGF-2 did prevent the development of a “fibroblastic” cell layer around pellet periphery. FGF-2 significantly accelerates in vitro SF-CP expansion, the major hurdle to clinical application of this cell population, without detrimentally affecting subsequent chondrogenic capacity.

A matched expansion approach to practical self-force calculations

International Nuclear Information System (INIS)

Anderson, Warren G; Wiseman, Alan G

2005-01-01

We discuss a practical method of computing the self-force on a particle moving through a curved spacetime. This method involves two expansions to calculate the self-force, one arising from the particle's immediate past and the other from the more distant past. The expansion in the immediate past is a covariant Taylor series and can be carried out for all geometries. The more distant expansion is a mode sum, and may be carried out in those cases where the wave equation for the field mediating the self-force admits a mode expansion of the solution. In particular, this method can be used to calculate the gravitational self-force for a particle of mass μ orbiting a black hole of mass M to order μ 2 , provided μ/M << 1. We discuss how to use these two expansions to construct a full self-force, and in particular investigate criteria for matching the two expansions. As with all methods of computing self-forces for particles moving in black hole spacetimes, one encounters considerable technical difficulty in applying this method; nevertheless, it appears that the convergence of each series is good enough that a practical implementation may be plausible

Whole genome duplications and expansion of the vertebrate GATA transcription factor gene family

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Bowerman Bruce

2009-08-01

Full Text Available Abstract Background GATA transcription factors influence many developmental processes, including the specification of embryonic germ layers. The GATA gene family has significantly expanded in many animal lineages: whereas diverse cnidarians have only one GATA transcription factor, six GATA genes have been identified in many vertebrates, five in many insects, and eleven to thirteen in Caenorhabditis nematodes. All bilaterian animal genomes have at least one member each of two classes, GATA123 and GATA456. Results We have identified one GATA123 gene and one GATA456 gene from the genomic sequence of two invertebrate deuterostomes, a cephalochordate (Branchiostoma floridae and a hemichordate (Saccoglossus kowalevskii. We also have confirmed the presence of six GATA genes in all vertebrate genomes, as well as additional GATA genes in teleost fish. Analyses of conserved sequence motifs and of changes to the exon-intron structure, and molecular phylogenetic analyses of these deuterostome GATA genes support their origin from two ancestral deuterostome genes, one GATA 123 and one GATA456. Comparison of the conserved genomic organization across vertebrates identified eighteen paralogous gene families linked to multiple vertebrate GATA genes (GATA paralogons, providing the strongest evidence yet for expansion of vertebrate GATA gene families via genome duplication events. Conclusion From our analysis, we infer the evolutionary birth order and relationships among vertebrate GATA transcription factors, and define their expansion via multiple rounds of whole genome duplication events. As the genomes of four independent invertebrate deuterostome lineages contain single copy GATA123 and GATA456 genes, we infer that the 0R (pre-genome duplication invertebrate deuterostome ancestor also had two GATA genes, one of each class. Synteny analyses identify duplications of paralogous chromosomal regions (paralogons, from single ancestral vertebrate GATA123 and GATA456

Interferon Regulator Factor 8 (IRF8 Limits Ocular Pathology during HSV-1 Infection by Restraining the Activation and Expansion of CD8+ T Cells.

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Lin Sun

Full Text Available Interferon Regulatory Factor-8 (IRF8 is constitutively expressed in monocytes and B cell lineages and plays important roles in immunity to pathogens and cancer. Although IRF8 expression is induced in activated T cells, the functional relevance of IRF8 in T cell-mediated immunity is not well understood. In this study, we used mice with targeted deletion of Irf8 in T-cells (IRF8KO to investigate the role of IRF8 in T cell-mediated responses during herpes simplex virus 1 (HSV-1 infection of the eye. In contrast to wild type mice, HSV-1-infected IRF8KO mice mounted a more robust anti-HSV-1 immune response, which included marked expansion of HSV-1-specific CD8+ T cells, increased infiltration of inflammatory cells into the cornea and trigeminal ganglia (TG and enhanced elimination of virus within the trigeminal ganglion. However, the consequence of the enhanced immunological response was the development of ocular inflammation, limbitis, and neutrophilic infiltration into the cornea of HSV-1-infected IRF8KO mice. Surprisingly, we observed a marked increase in virus-specific memory precursor effector cells (MPEC in IRF8KO mice, suggesting that IRF8 might play a role in regulating the differentiation of effector CD8+ T cells to the memory phenotype. Together, our data suggest that IRF8 might play a role in restraining excess lymphocyte proliferation. Thus, modulating IRF8 levels in T cells can be exploited therapeutically to prevent immune-mediated ocular pathology during autoimmune and infectious diseases of the eye.

What factors mediate the relationship between global self-worth and weight and shape concerns?

Science.gov (United States)

Murphy, Edel; Dooley, Barbara; Menton, Aoife; Dolphin, Louise

2016-04-01

The primary aim of this study was to investigate whether the relationship between global self-worth and weight concerns and global self-worth and shape concerns was mediated by pertinent body image factors, while controlling for gender and estimated BMI. Participants were 775 adolescents (56% male) aged 12-18years (M=14.6; SD=1.50). Mediation analysis revealed a direct and a mediated effect between global self-worth and two body image models: 1) weight concerns and 2) shape concerns. The strongest mediators in both models were physical appearance, restrained eating, and depression. Partial mediation was observed for both models, indicating that body image factors which span cognitive, affective, and behavioral constructs, explain the association between global self-worth and weight and shape concerns. Implications for future research, weight and shape concern prevention and global self-worth enhancement programs are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

The influence of gender on entrepreneurial intention: The mediating role of perceptual factors

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Carmen Camelo-Ordaz

2016-10-01

Full Text Available The empirical evidence devoted to analyze the impact of perceptual factors in explaining the differences in the entrepreneurial intention of men and women is still limited and not entirely conclusive (Shinnar et al., 2012; Wilson et al., 2009. This non-conclusive research is significantly more noteworthy when the analysis is focused on the entrepreneurial intention of men and women once they become entrepreneurs. Drawing on this gap and taking as starting point the premises of Social Feminist Theory, our paper aims to examine the mediating role of perceptual factors on the relationship between gender and entrepreneurial intention of non-entrepreneurs and entrepreneurs. Drawing on a sample provided by the Global Entrepreneurship Monitor Project of 21,697 Spanish non-entrepreneurs and 2899 Spanish entrepreneurs, our results have shown that, in general terms, perceptual factor fully mediate the relationship between gender and the entrepreneurial intention of non-entrepreneurs, whereas such mediating impact disappears when people become entrepreneurs.

Socioeconomic status and risk factors for cardiovascular disease: Impact of dietary mediators.

Science.gov (United States)

Psaltopoulou, Theodora; Hatzis, George; Papageorgiou, Nikolaos; Androulakis, Emmanuel; Briasoulis, Alexandros; Tousoulis, Dimitris

It is well known that cardiovascular disease is the leading cause of mortality in the western societies. A number of risk factors such as family history, diabetes, hypertension, obesity, diabetes, smoking and physical inactivity are responsible for a significant proportion of the overall cardiovascular risk. Interestingly, recent data suggest there is a gradient in the incidence, morbidity and mortality of cardiovascular disease across the spectrum of socioeconomic status, as this is defined by educational level, occupation or income. Additionally, dietary mediators seem to play significant role in the pathogenesis of cardiovascular disease, mediating some of the discrepancies in atherosclerosis among different socioeconomic layers. Therefore, in the present article, we aim to review the association between socioeconomic status and cardiovascular disease risk factors and the role of different dietary mediators. Copyright © 2017 Hellenic Society of Cardiology. Published by Elsevier B.V. All rights reserved.

The expansion of electric power systems considering the operation reliability; Expansion de sistemas electricos considerando la securidad de servicio

Energy Technology Data Exchange (ETDEWEB)

Cortes, Marcelo A. [Universidad de Antofagasta (Chile). Dept. de Ingenieria Electrica; Moya A, Oscar [Chile Univ., Santiago (Chile). Dept. de Ingenieria Civil

1997-12-31

This publication describes a procedure based in an linear programming for the planning of the expansion of mediating term in power systems. The implicit alternatives for network expansion, whether power plants or transmission lines, are classified according to indexes of reinforcement. The indexes are gotten resulting shadow pricing upon resolving a problem of minimum cost of operation and outage. The network is subjected to the most probable contingencies and from these outputs the expected reinforcement results are obtained. The problem of the reactive power accounts for restrictions in line capacity and prior evaluation of A C power flux. Results obtained are used for methodology validation. (author) 12 refs., 1 fig., 3 tabs.; e-mail: mcortes at apolo.cc.uantof.cl.; osmoya at tamarugo.cec.uchile.cl

Stat6 Promotes Intestinal Tumorigenesis in a Mouse Model of Adenomatous Polyposis by Expansion of MDSCs and Inhibition of Cytotoxic CD8 Response

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Asha Jayakumar

2017-08-01

Full Text Available Intestinal tumorigenesis in the ApcMin/+ model is initiated by aberrant activation of Wnt pathway. Increased IL-4 expression in human colorectal cancer tissue and growth of colon cancer cell lines implied that IL-4–induced Stat6-mediated tumorigenic signaling likely contributes to intestinal tumor progression in ApcMin/+ mice. Stat6 also appears to promote expansion of myeloid-derived suppressor cells (MDSCs cells. MDSCs promote polyp formation in the ApcMin/+ model. Hence, Stat6 could have a broad role in coordinating both polyp cell proliferation and MDSC expansion. We found that IL-4–induced Stat6-mediated proliferation of intestinal epithelial cells is augmented by platelet-derived growth factor–BB, a tumor-promoting growth factor. To determine whether polyp progression in ApcMin/+ mice is dependent on Stat6 signaling, we disrupted Stat6 in this model. Total polyps in the small intestine were fewer in ApcMin/+ mice lacking Stat6. Furthermore, proliferation of polyp epithelial cells was reduced, indicating that Stat6 in part controlled polyp formation. Stat6 also promoted expansion of MDSCs in the spleen and lamina propria of ApcMin/+ mice, implying regulation of antitumor T-cell response. More CD8 cells and reduced PD-1 expression on CD4 cells correlated with reduced polyps. In addition, a strong CD8-mediated cytotoxic response led to killing of tumor cells in Stat6-deficient ApcMin/+ mice. Therefore, these findings show that Stat6 has an oncogenic role in intestinal tumorigenesis by promoting polyp cell proliferation and immunosuppressive mediators, and preventing an active cytotoxic process.

Psychosocial factors partially mediate the relationship between mechanical hyperalgesia and self-reported pain.

Science.gov (United States)

Mason, Kayleigh J; O'Neill, Terence W; Lunt, Mark; Jones, Anthony K P; McBeth, John

2018-01-26

Amplification of sensory signalling within the nervous system along with psychosocial factors contributes to the variation and severity of knee pain. Quantitative sensory testing (QST) is a non-invasive test battery that assesses sensory perception of thermal, pressure, mechanical and vibration stimuli used in the assessment of pain. Psychosocial factors also have an important role in explaining the occurrence of pain. The aim was to determine whether QST measures were associated with self-reported pain, and whether those associations were mediated by psychosocial factors. Participants with knee pain identified from a population-based cohort completed a tender point count and a reduced QST battery of thermal, mechanical and pressure pain thresholds, temporal summation, mechanical pain sensitivity (MPS), dynamic mechanical allodynia (DMA) and vibration detection threshold performed following the protocol by the German Research Network on Neuropathic Pain. QST assessments were performed at the most painful knee and opposite forearm (if pain-free). Participants were asked to score for their global and knee pain intensities within the past month (range 0-10), and complete questionnaire items investigating anxiety, depression, illness perceptions, pain catastrophising, and physical functioning. QST measures (independent variable) significantly correlated (Spearman's rho) with self-reported pain intensity (dependent variable) were included in structural equation models with psychosocial factors (latent mediators). Seventy-two participants were recruited with 61 participants (36 women; median age 64 years) with complete data included in subsequent analyses. Tender point count was significantly correlated with global pain intensity. DMA at the knee and MPS at the most painful knee and opposite pain-free forearm were significantly correlated with both global pain and knee pain intensities. Psychosocial factors including pain catastrophising sub-scales (rumination and

Biomass conversion and expansion factors are afected by thinning

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Teresa Duque Enes

2014-12-01

Full Text Available Aim of the study: The objective of this paper is to investigate the use of Biomass Conversion and Expansion Factors (BCEFs in maritime pine (Pinus pinaster Ait. stands subjected to thinning.Area of the study: The study area refers to different ecosystems of maritime pine stands inNorthern Portugal.Material and methods: The study is supported by time data series and cross sectional data collected in permanent plots established in the North of Portugal. An assessment of BCEF values for the aboveground compartments and for total was completed for each studied stand. Identification of key variables affecting the value of the BCEFs in time and with thinning was conducted using correlation analysis. Predictive models for estimation of the BCEFs values in time and after thinning were developed using nonlinear regression analysis.Research highlights: For periods of undisturbed growth, the results show an allometric relationship between the BCEFs, the dominant height and the mean diameter. Management practices such as thinning also influence the factors. Estimates of the ratio change before and after thinning depend on thinning severity and thinning type. The developed models allow estimating the biomass of the stands, for the aboveground compartments and for total, based on information of stand characteristics and of thinning descriptors. These estimates can be used to assess the forest dry wood stocks to be used for pulp, bioenergy or other purposes, as well as the biomass quantification to support the evaluation of the net primary productivity.Keywords: carbon; softwood; thinning; volume; wood energy; maritime pine.

The psychological aftermath of bereavement : Risk factors, mediating processes, and intervention

OpenAIRE

Van der Houwen, H.K.

2009-01-01

In this dissertation some of the major facets associated with the psychological effects of bereavement were the subject of investigation: risk factors, mediating processes and intervention. Previous research on risk factors is limited because of a number of methodological shortcomings: a focus on only one or a few factors (which increases the chances of reporting spurious results) and reliance on use of a single measure of bereavement outcome. We avoided these pitfalls by simultaneously exami...

Rapid replacement of bridge deck expansion joints study - phase I.

Science.gov (United States)

2014-12-01

Bridge deck expansion joints are used to allow for movement of the bridge deck due to thermal expansion, dynamics loading, and : other factors. More recently, expansion joints have also been utilized to prevent the passage of winter de-icing chemical...

Dejavniki uspešnosti mediacije v sodnih sporih = Factors of Mediation Success in Court Disputes

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Roberto Biloslavo

2009-09-01

Full Text Available A massive decrease in successful mediation procedures at the AlternativeDispute Resolution Department at the District Court in Ljubljanaraises the question of what its causes are. To recognize factorsthat contribute to a successful mediation we did qualitative researchon a sample of nine mediators. It was determined in the research thatthe mediators believe that the factors which greatly influence the decreasein successfulness in mediation procedures are: the manner ofrealization of mediation procedure, phase in which the dispute shouldbe solved with mediations, role of the judge in the phase of startingmediation, suitability of dispute for mediation, possibility to choose amediator, mediator himself, use of method for dispute resolution, separateand joint sessions and payability of mediation procedure. In conclusion,we present guidelines and proposals according to researchfindings.

Ex-vivo expansion of nonhuman primate CD34+ cells by stem cell factor Sall4B

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Bin Shen

2016-10-01

Full Text Available Abstract Background Hematopoietic CD34+ stem cells are widely used in the clinical therapy of complicated blood diseases. Stem cell factor Sall4B is a zinc finger transcription factor that plays a vital role in hematopoietic stem cell expansion. The purpose of our current study is to further evaluate how Sall4B might affect the expansion of CD34+ cells derived from nonhuman primates. Methods Sall4B was overexpressed in nonhuman primate bone marrow-derived CD34+ cells via a lentiviral transduction system. The granulocyte–erythrocyte–macrophage–megakaryocyte colony-forming unit (CFU assay evaluated the differentiation potential of primate CD34+ cells that were expanded with Sall4B. Furthermore, an in-vivo murine system was employed to evaluate the hematopoietic potential of primate Sall4B-expanded CD34+ cells. Results Overexpression of Sall4B promoted ex-vivo nonhuman primate CD34+ cell expansion by 9.21 ± 1.94-fold on day 9, whereas lentiviral transduction without Sall4B expanded cells by only 2.95 ± 0.77-fold. Sall4B maintained a significant percentage of CD34+ cells as well. The CFU assay showed that the Sall4B-expanded CD34+ cells still possessed multilineage differentiation potential. A study using nonobese diabetic/severe combined immunodeficiency (NOD/SCID mice in vivo revealed that Sall4B led to an increase in the number of repopulating cells and the 9-day-old Sall4B-transduced CD34+ cells still possess self-renewal and multilineage differentiation capacity in vivo, which are similar stemness characteristics to those in freshly isolated primate bone marrow-derived CD34+ cells. Conclusions We investigated the expansion of nonhuman primate bone marrow-derived CD34+ cells using the Sall4B lentiviral overexpression approach; our findings provide a new perspective on mechanisms of rapid stem cell proliferation. The utilization of Sall4B to expand CD34+ cells on a large scale through use of suitable model systems would prove

Differential effects of IL-2 and IL-21 on expansion of the CD4+ CD25+ Foxp3+ T regulatory cells with redundant roles in natural killer cell mediated antibody dependent cellular cytotoxicity in chronic lymphocytic leukemia.

Science.gov (United States)

Gowda, Aruna; Ramanunni, Asha; Cheney, Carolyn; Rozewski, Darlene; Kindsvogel, Wayne; Lehman, Amy; Jarjoura, David; Caligiuri, Michael; Byrd, John C; Muthusamy, Natarajan

2010-01-01

CD4(+) CD25(+) regulatory T cells are expanded in solid and hematological malignancies including chronic lymphocytic leukemia (CLL). Several cytokines and co-stimulatory molecules are required for generation, survival and maintenance of their suppressive effect. We and others have shown direct cytotoxic effect of the novel common gamma chain cytokine interleukin (IL)-21 on primary B cells from CLL patients. Since members of this family of cytokines are known to exhibit their effects on diverse immune cells, we have examined the effects of IL-21 on CLL patient derived regulatory T cell (Treg) induction, expansion and the inhibitory effect on natural killer cells in vitro. We demonstrate here the expression of IL-21 receptor in CD4(+)CD25(High) regulatory cells from CLL patients. In contrast to IL-2, the IL-21 cytokine failed to mediate expansion of regulatory T cells or induced expression of Foxp3 in CD4(+)CD25(Intermediate) or CD4(+)CD25(Dim/-) T cells in whole blood derived from CLL patients. Interestingly, in contrast to their differential effects on expansion of the CD4(+)CD25(+)Foxp3(+)T cells, IL-2 and IL-21 exhibited a redundant role in Treg mediated suppression of NK cell mediated antibody dependent cytotoxicity function. Given the infusion related toxicities and pro-survival effect of IL-2 in CLL, these studies provide a rationale to explore IL-21 as an alternate gamma chain cytokine in CLL therapy.

Macrophages control vascular stem/progenitor cell plasticity through tumor necrosis factor-α-mediated nuclear factor-κB activation.

Science.gov (United States)

Wong, Mei Mei; Chen, Yikuan; Margariti, Andriani; Winkler, Bernhard; Campagnolo, Paola; Potter, Claire; Hu, Yanhua; Xu, Qingbo

2014-03-01

Vascular lineage differentiation of stem/progenitor cells can contribute to both tissue repair and exacerbation of vascular diseases such as in vein grafts. The role of macrophages in controlling vascular progenitor differentiation is largely unknown and may play an important role in graft development. This study aims to identify the role of macrophages in vascular stem/progenitor cell differentiation and thereafter elucidate the mechanisms that are involved in the macrophage- mediated process. We provide in vitro evidence that macrophages can induce endothelial cell (EC) differentiation of the stem/progenitor cells while simultaneously inhibiting their smooth muscle cell differentiation. Mechanistically, both effects were mediated by macrophage-derived tumor necrosis factor-α (TNF-α) via TNF-α receptor 1 and canonical nuclear factor-κB activation. Although the overexpression of p65 enhanced EC (or attenuated smooth muscle cell) differentiation, p65 or TNF-α receptor 1 knockdown using lentiviral short hairpin RNA inhibited EC (or rescued smooth muscle cell) differentiation in response to TNF-α. Furthermore, TNF-α-mediated EC differentiation was driven by direct binding of nuclear factor-κB (p65) to specific VE-cadherin promoter sequences. Subsequent experiments using an ex vivo decellularized vessel scaffold confirmed an increase in the number of ECs and reduction in smooth muscle cell marker expression in the presence of TNF-α. The lack of TNF-α in a knockout mouse model of vein graft decreased endothelialization and significantly increased thrombosis formation. Our study highlights the role of macrophages in directing vascular stem/progenitor cell lineage commitment through TNF-α-mediated TNF-α receptor 1 and nuclear factor-κB activation that is likely required for endothelial repair in vascular diseases such as vein graft.

DNA dynamics is likely to be a factor in the genomic nucleotide repeats expansions related to diseases.

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Boian S Alexandrov

Full Text Available Trinucleotide repeats sequences (TRS represent a common type of genomic DNA motif whose expansion is associated with a large number of human diseases. The driving molecular mechanisms of the TRS ongoing dynamic expansion across generations and within tissues and its influence on genomic DNA functions are not well understood. Here we report results for a novel and notable collective breathing behavior of genomic DNA of tandem TRS, leading to propensity for large local DNA transient openings at physiological temperature. Our Langevin molecular dynamics (LMD and Markov Chain Monte Carlo (MCMC simulations demonstrate that the patterns of openings of various TRSs depend specifically on their length. The collective propensity for DNA strand separation of repeated sequences serves as a precursor for outsized intermediate bubble states independently of the G/C-content. We report that repeats have the potential to interfere with the binding of transcription factors to their consensus sequence by altered DNA breathing dynamics in proximity of the binding sites. These observations might influence ongoing attempts to use LMD and MCMC simulations for TRS-related modeling of genomic DNA functionality in elucidating the common denominators of the dynamic TRS expansion mutation with potential therapeutic applications.

THE EXPANSION OF FDI FLOWS – A MAJOR FACTOR OF GLOBALIZATION

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CLAUDIA ISAC

2011-01-01

Full Text Available Globalization is the process whereby geographical distance becomes a less important factor in establishing and developing cross-border economic, political and socio-cultural relations; therefore production networks and Foreign Direct Investment (FDI flows represent the main factors that play a key role in the process of getting international and worldwide spreading. Globalization phenomenon involves a process of deepening and widening of interdependence relations between different economic entities and spheres and takes into account international trade relations, the cross-border movement of international production factors, but mostly the expansion of FDI flows, having significant positive effects on the welfare of nations or geographical areas. The impact of the global economic crisis on FDI flows is a heterogeneous one, as the effects of the depression came to light in many different ways, depending on the level of development, the geographical area or the economic field. The overall fall in global FDI flows during the crisis was accompanied by a significant shift in the traditional pattern of FDI: emerging countries well-endowed with natural resources were becoming a growing source of FDI for developed countries, due to internationalization strategies carried out by their multinational companies (MNCs. Based on recent forecasts, UNCTAD specialists estimate that global FDI will recover to its pre-crisis level in 2011, rising to $1.4-1.6 trillion, approaching its 2007 peak in 2013. However, the business environment remains volatile and MNCs are cautious rather than optimistic regarding their investment plans.

Going Up? The Pros and Cons of Vertical Expansion.

Science.gov (United States)

Myler, Patricia A.; Boggs, Richard C.

2002-01-01

Describes the advantages and disadvantages of the vertical expansion of school buildings. Considers such factors as fire protection, compliance with the Americans with Disabilities Act, and cost. Discusses alternatives to vertical expansion. (PKP)

Nerve growth factor expression by PLG-mediated lipofection.

Science.gov (United States)

Whittlesey, Kevin J; Shea, Lonnie D

2006-04-01

Biomaterials capable of efficient gene delivery provide a fundamental tool for basic and applied research models, such as promoting neural regeneration. We developed a system for the encapsulation and sustained release of plasmid DNA complexed with a cationic lipid and investigated their efficacy using in vitro models of neurite outgrowth. Sustained lipoplex release was obtained for up to 50 days, with rates controlled by the fabrication conditions. Released lipoplexes retained their activity, transfecting 48.2+/-8.3% of NIH3T3 cells with luciferase activity of 3.97x10(7)RLU/mg. Expression of nerve growth factor (NGF) was employed in two models of neurite outgrowth: PC12 and primary dorsal root ganglia (DRG) co-culture. Polymer-mediated lipofection of PC12 produced bioactive NGF, eliciting robust neurite outgrowth. An EGFP/NGF dual-expression vector identified transfected cells (GFP-positive) while neurite outgrowth verified NGF secretion. A co-culture model examined the ability of NGF secretion by an accessory cell population to stimulate DRG neurite outgrowth. Polymer-mediated transfection of HEK293T with an NGF-encoding plasmid induced outgrowth by DRG neurons. This system could be fabricated as implants or nerve guidance conduits to support cellular and tissue regeneration. Combining this physical support with the ability to locally express neurotrophic factors will potentiate regeneration in nerve injury and disease models.

A treatment of expansive soil using different additives

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Bestun J. Nareeman

2010-11-01

Full Text Available There are many factors that govern the expansion behavior of soil. The primary factors are a change in water contentand the amount and type of clay size particles in the soil. Other important factors affecting the expansion behavior include the typeof soil (natural or fill, condition of the soil in terms of dry density and moisture content, magnitude of the surcharge pressure,and amount of no expansive material such as gravel or cobble size particles.In this paper, a swelling soil from the site Hamamuk earth dam, which is located in Koya town north of Iraq, is treated by fourtypes of additives; cement, steel fibers, gasoline fuel and injection by cement grout.The treatment of the expansive soil with 5 % of cement or steel fibers or the injection with cement grout revealed a betterimprovement while 4 % of gasoline oil is sufficient to reveal the optimum treatment by this material. The angle of internal friction is notaffected by the treatment while the cohesion between particles is slightly affected by these additives due to a change in the adhesionbetween the additive and soil particles.

Research progress on expansive soil cracks under changing environment.

Science.gov (United States)

Shi, Bei-xiao; Zheng, Cheng-feng; Wu, Jin-kun

2014-01-01

Engineering problems shunned previously rise to the surface gradually with the activities of reforming the natural world in depth, the problem of expansive soil crack under the changing environment becoming a control factor of expansive soil slope stability. The problem of expansive soil crack has gradually become a research hotspot, elaborates the occurrence and development of cracks from the basic properties of expansive soil, and points out the role of controlling the crack of expansive soil strength. We summarize the existing research methods and results of expansive soil crack characteristics. Improving crack measurement and calculation method and researching the crack depth measurement, statistical analysis method, crack depth and surface feature relationship will be the future direction.

Mediating Effects of Intention On The Factors Affecting Organic Food Products Consumption Among Chinese Generation Y In Malaysia

OpenAIRE

Tan Poh Leong; Laily Paim

2015-01-01

This study aimed to measure the effect of intention as a mediator in the relationship between internal factors and external factors on consumption. The factors were a) internal factors: knowledge, awareness, health consciousness, product attributes, environmental concern, and b) external factors: subjective norms, perceived behaviour control, and media and advertisement. From the review of literature, there were limited studies done on the mediating effect of intention on the relationship bet...

Educational inequalities in TV viewing among older adults: a mediation analysis of ecological factors.

Science.gov (United States)

De Cocker, Katrien; De Bourdeaudhuij, Ilse; Teychenne, Megan; McNaughton, Sarah; Salmon, Jo

2013-12-19

Television (TV) viewing, a prevalent leisure-time sedentary behaviour independently related to negative health outcomes, appears to be higher in less educated and older adults. In order to tackle the social inequalities, evidence is needed about the underlying mechanisms of the association between education and TV viewing. The present purpose was to examine the potential mediating role of personal, social and physical environmental factors in the relationship between education and TV viewing among Australian 55-65 year-old adults. In 2010, self-reported data was collected among 4082 adults (47.6% men) across urban and rural areas of Victoria, for the Wellbeing, Eating and Exercise for a Long Life (WELL) study. The mediating role of personal (body mass index [BMI], quality of life), social (social support from family and friends, social participation at proximal level, and interpersonal trust, social cohesion, personal safety at distal level) and physical environmental (neighbourhood aesthetics, neighbourhood physical activity environment, number of televisions) factors in the association between education and TV viewing time was examined using the product-of-coefficients test of MacKinnon based on multilevel linear regression analyses (conducted in 2012). Multiple mediating analyses showed that BMI (p ≤ 0.01), personal safety (p TV viewing. No proximal social factors mediated the education-TV viewing association. Interventions aimed to reduce TV viewing should focus on personal (BMI) and environmental (personal safety, neighbourhood aesthetics, number of televisions) factors, in order to overcome educational inequalities in sedentary behaviour among older adults.

Mediating Business

DEFF Research Database (Denmark)

"Mediating Business" is a study of the expansion of business journalism. Building on evidence from Denmark, Finland, Norway and Sweden, "Mediating Business" is a comparative and multidisciplinary study of one of the major transformations of the mass media and the realm of business - nationally...... and globally. The book explores the history of key innovations and innovators in the business press. It analyzes changes in the discourse of business journalism associated with the growth in business news and the development of new ways of framing business issues and events. Finally, it examines...... the organizational implications of the increased media visibility of business and, in particular, the development of corporate governance and media relations....

Structure of the N-terminal domain of the protein Expansion: an ‘Expansion’ to the Smad MH2 fold

International Nuclear Information System (INIS)

Beich-Frandsen, Mads; Aragón, Eric; Llimargas, Marta; Benach, Jordi; Riera, Antoni; Pous, Joan; Macias, Maria J.

2015-01-01

Expansion is a modular protein that is conserved in protostomes. The first structure of the N-terminal domain of Expansion has been determined at 1.6 Å resolution and the new Nα-MH2 domain was found to belong to the Smad/FHA superfamily of structures. Gene-expression changes observed in Drosophila embryos after inducing the transcription factor Tramtrack led to the identification of the protein Expansion. Expansion contains an N-terminal domain similar in sequence to the MH2 domain characteristic of Smad proteins, which are the central mediators of the effects of the TGF-β signalling pathway. Apart from Smads and Expansion, no other type of protein belonging to the known kingdoms of life contains MH2 domains. To compare the Expansion and Smad MH2 domains, the crystal structure of the Expansion domain was determined at 1.6 Å resolution, the first structure of a non-Smad MH2 domain to be characterized to date. The structure displays the main features of the canonical MH2 fold with two main differences: the addition of an α-helical region and the remodelling of a protein-interaction site that is conserved in the MH2 domain of Smads. Owing to these differences, to the new domain was referred to as Nα-MH2. Despite the presence of the Nα-MH2 domain, Expansion does not participate in TGF-β signalling; instead, it is required for other activities specific to the protostome phyla. Based on the structural similarities to the MH2 fold, it is proposed that the Nα-MH2 domain should be classified as a new member of the Smad/FHA superfamily

Structure of the N-terminal domain of the protein Expansion: an ‘Expansion’ to the Smad MH2 fold

Energy Technology Data Exchange (ETDEWEB)

Beich-Frandsen, Mads; Aragón, Eric [Institute for Research in Biomedicine (IRB Barcelona), Baldiri Reixac 10, 08028 Barcelona (Spain); Llimargas, Marta [Institut de Biologia Molecular de Barcelona, IBMB–CSIC, Baldiri Reixac 10, 08028 Barcelona (Spain); Benach, Jordi [ALBA Synchrotron, BP 1413, km 3.3, Cerdanyola del Vallès (Spain); Riera, Antoni [Institute for Research in Biomedicine (IRB Barcelona), Baldiri Reixac 10, 08028 Barcelona (Spain); Universitat de Barcelona, Martí i Franqués 1-11, 08028 Barcelona (Spain); Pous, Joan [Institute for Research in Biomedicine (IRB Barcelona), Baldiri Reixac 10, 08028 Barcelona (Spain); Platform of Crystallography IBMB–CSIC, Baldiri Reixac 10, 08028 Barcelona (Spain); Macias, Maria J., E-mail: maria.macias@irbbarcelona.org [Institute for Research in Biomedicine (IRB Barcelona), Baldiri Reixac 10, 08028 Barcelona (Spain); Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluís Companys 23, 08010 Barcelona (Spain)

2015-04-01

Expansion is a modular protein that is conserved in protostomes. The first structure of the N-terminal domain of Expansion has been determined at 1.6 Å resolution and the new Nα-MH2 domain was found to belong to the Smad/FHA superfamily of structures. Gene-expression changes observed in Drosophila embryos after inducing the transcription factor Tramtrack led to the identification of the protein Expansion. Expansion contains an N-terminal domain similar in sequence to the MH2 domain characteristic of Smad proteins, which are the central mediators of the effects of the TGF-β signalling pathway. Apart from Smads and Expansion, no other type of protein belonging to the known kingdoms of life contains MH2 domains. To compare the Expansion and Smad MH2 domains, the crystal structure of the Expansion domain was determined at 1.6 Å resolution, the first structure of a non-Smad MH2 domain to be characterized to date. The structure displays the main features of the canonical MH2 fold with two main differences: the addition of an α-helical region and the remodelling of a protein-interaction site that is conserved in the MH2 domain of Smads. Owing to these differences, to the new domain was referred to as Nα-MH2. Despite the presence of the Nα-MH2 domain, Expansion does not participate in TGF-β signalling; instead, it is required for other activities specific to the protostome phyla. Based on the structural similarities to the MH2 fold, it is proposed that the Nα-MH2 domain should be classified as a new member of the Smad/FHA superfamily.

An Arabidopsis kinase cascade influences auxin-responsive cell expansion.

Science.gov (United States)

Enders, Tara A; Frick, Elizabeth M; Strader, Lucia C

2017-10-01

Mitogen-activated protein kinase (MPK) cascades are conserved mechanisms of signal transduction across eukaryotes. Despite the importance of MPK proteins in signaling events, specific roles for many Arabidopsis MPK proteins remain unknown. Multiple studies have suggested roles for MPK signaling in a variety of auxin-related processes. To identify MPK proteins with roles in auxin response, we screened mpk insertional alleles and identified mpk1-1 as a mutant that displays hypersensitivity in auxin-responsive cell expansion assays. Further, mutants defective in the upstream MAP kinase kinase MKK3 also display hypersensitivity in auxin-responsive cell expansion assays, suggesting that this MPK cascade affects auxin-influenced cell expansion. We found that MPK1 interacts with and phosphorylates ROP BINDING PROTEIN KINASE 1 (RBK1), a protein kinase that interacts with members of the Rho-like GTPases from Plants (ROP) small GTPase family. Similar to mpk1-1 and mkk3-1 mutants, rbk1 insertional mutants display auxin hypersensitivity, consistent with a possible role for RBK1 downstream of MPK1 in influencing auxin-responsive cell expansion. We found that RBK1 directly phosphorylates ROP4 and ROP6, supporting the possibility that RBK1 effects on auxin-responsive cell expansion are mediated through phosphorylation-dependent modulation of ROP activity. Our data suggest a MKK3 • MPK1 • RBK1 phosphorylation cascade that may provide a dynamic module for altering cell expansion. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

IL-10 Production Is Critical for Sustaining the Expansion of CD5+ B and NKT Cells and Restraining Autoantibody Production in Congenic Lupus-Prone Mice.

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Yuriy Baglaenko

Full Text Available The development and progression of systemic lupus erythematosus is mediated by the complex interaction of genetic and environmental factors. To decipher the genetics that contribute to pathogenesis and the production of pathogenic autoantibodies, our lab has focused on the generation of congenic lupus-prone mice derived from the New Zealand Black (NZB strain. Previous work has shown that an NZB-derived chromosome 4 interval spanning 32 to 151 Mb led to expansion of CD5+ B and Natural Killer T (NKT cells, and could suppress autoimmunity when crossed with a lupus-prone mouse strain. Subsequently, it was shown that CD5+ B cells but not NKT cells derived from these mice could suppress the development of pro-inflammatory T cells. In this paper, we aimed to further resolve the genetics that leads to expansion of these two innate-like populations through the creation of additional sub-congenic mice and to characterize the role of IL-10 in the suppression of autoimmunity through the generation of IL-10 knockout mice. We show that expansion of CD5+ B cells and NKT cells localizes to a chromosome 4 interval spanning 91 to 123 Mb, which is distinct from the region that mediates the majority of the suppressive phenotype. We also demonstrate that IL-10 is critical to restraining autoantibody production and surprisingly plays a vital role in supporting the expansion of innate-like populations.

IL-10 Production Is Critical for Sustaining the Expansion of CD5+ B and NKT Cells and Restraining Autoantibody Production in Congenic Lupus-Prone Mice.

Science.gov (United States)

Baglaenko, Yuriy; Manion, Kieran P; Chang, Nan-Hua; Gracey, Eric; Loh, Christina; Wither, Joan E

2016-01-01

The development and progression of systemic lupus erythematosus is mediated by the complex interaction of genetic and environmental factors. To decipher the genetics that contribute to pathogenesis and the production of pathogenic autoantibodies, our lab has focused on the generation of congenic lupus-prone mice derived from the New Zealand Black (NZB) strain. Previous work has shown that an NZB-derived chromosome 4 interval spanning 32 to 151 Mb led to expansion of CD5+ B and Natural Killer T (NKT) cells, and could suppress autoimmunity when crossed with a lupus-prone mouse strain. Subsequently, it was shown that CD5+ B cells but not NKT cells derived from these mice could suppress the development of pro-inflammatory T cells. In this paper, we aimed to further resolve the genetics that leads to expansion of these two innate-like populations through the creation of additional sub-congenic mice and to characterize the role of IL-10 in the suppression of autoimmunity through the generation of IL-10 knockout mice. We show that expansion of CD5+ B cells and NKT cells localizes to a chromosome 4 interval spanning 91 to 123 Mb, which is distinct from the region that mediates the majority of the suppressive phenotype. We also demonstrate that IL-10 is critical to restraining autoantibody production and surprisingly plays a vital role in supporting the expansion of innate-like populations.

Crude oil pipeline expansion summary

International Nuclear Information System (INIS)

2005-02-01

The Canadian Association of Petroleum Producers has been working with producers to address issues associated with the development of new pipeline capacity from western Canada. This document presents an assessment of the need for additional oil pipeline capacity given the changing mix of crude oil types and forecasted supply growth. It is of particular interest to crude oil producers and contributes to current available information for market participants. While detailed, the underlying analysis does not account for all the factors that may come into play when individual market participants make choices about which expansions they may support. The key focus is on the importance of timely expansion. It was emphasized that if pipeline expansions lags the crude supply growth, then the consequences would be both significant and unacceptable. Obstacles to timely expansion are also discussed. The report reviews the production and supply forecasts, the existing crude oil pipeline infrastructure, opportunities for new market development, requirements for new pipeline capacity and tolling options for pipeline development. tabs., figs., 1 appendix

Linking admiration and adoration to self-expansion: different ways to enhance one's potential.

Science.gov (United States)

Schindler, Ines; Paech, Juliane; Löwenbrück, Fabian

2015-01-01

How is admiration different from adoration? We provided one answer to this question by examining the pathways through which admiration and adoration linked to self-expansion in a questionnaire and an experimental (autobiographical recall of emotion episodes) study. Both emotions were associated with increased potential efficacy to accomplish goals (i.e., self-expansion), but different action tendencies accounted for these links. While our emotion inductions did not successfully distinguish between admiration and adoration, we could statistically disentangle their effects through mediator models. In both studies, self-reported admiration linked to self-expansion through the tendency to emulate admired others. Adoration related to self-expansion through the tendency to affiliate with adored others. These findings were obtained after controlling for other emotions in response to the target person (awe, love, hope, benign envy) and mutuality of the relationship. Our findings also suggest that considering specific emotions (rather than undifferentiated positive affect) helps uncover different pathways to self-expansion.

Cryo-electron microscopy and single molecule fluorescent microscopy detect CD4 receptor induced HIV size expansion prior to cell entry

International Nuclear Information System (INIS)

Pham, Son; Tabarin, Thibault; Garvey, Megan; Pade, Corinna; Rossy, Jérémie; Monaghan, Paul; Hyatt, Alex; Böcking, Till; Leis, Andrew; Gaus, Katharina; Mak, Johnson

2015-01-01

Viruses are often thought to have static structure, and they only remodel after the viruses have entered target cells. Here, we detected a size expansion of virus particles prior to viral entry using cryo-electron microscopy (cryo-EM) and single molecule fluorescence imaging. HIV expanded both under cell-free conditions with soluble receptor CD4 (sCD4) targeting the CD4 binding site on the HIV-1 envelope protein (Env) and when HIV binds to receptor on cellular membrane. We have shown that the HIV Env is needed to facilitate receptor induced virus size expansions, showing that the ‘lynchpin’ for size expansion is highly specific. We demonstrate that the size expansion required maturation of HIV and an internal capsid core with wild type stability, suggesting that different HIV compartments are linked and are involved in remodelling. Our work reveals a previously unknown event in HIV entry, and we propose that this pre-entry priming process enables HIV particles to facilitate the subsequent steps in infection. - Highlights: • Cell free viruses are able to receive external trigger that leads to apparent size expansion. • Virus envelope and CD4 receptor engagement is the lynchpin of virus size expansion. • Internal capsid organisation can influence receptor mediated virus size expansion. • Pre-existing virus-associated lipid membrane in cell free virus can accommodate the receptor mediated virus size expansion.

Cryo-electron microscopy and single molecule fluorescent microscopy detect CD4 receptor induced HIV size expansion prior to cell entry

Energy Technology Data Exchange (ETDEWEB)

Pham, Son [Deakin University, Victoria 3216 (Australia); CSIRO Australian Animal Health Laboratory, Victoria 3220 (Australia); Tabarin, Thibault [ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, New South Wales 3220 (Australia); Garvey, Megan; Pade, Corinna [Deakin University, Victoria 3216 (Australia); CSIRO Australian Animal Health Laboratory, Victoria 3220 (Australia); Rossy, Jérémie [ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, New South Wales 3220 (Australia); Monaghan, Paul; Hyatt, Alex [CSIRO Australian Animal Health Laboratory, Victoria 3220 (Australia); Böcking, Till [ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, New South Wales 3220 (Australia); Leis, Andrew [CSIRO Australian Animal Health Laboratory, Victoria 3220 (Australia); Gaus, Katharina, E-mail: k.gaus@unsw.edu.au [ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, New South Wales 3220 (Australia); Mak, Johnson, E-mail: j.mak@deakin.edu.au [Deakin University, Victoria 3216 (Australia); CSIRO Australian Animal Health Laboratory, Victoria 3220 (Australia)

2015-12-15

Viruses are often thought to have static structure, and they only remodel after the viruses have entered target cells. Here, we detected a size expansion of virus particles prior to viral entry using cryo-electron microscopy (cryo-EM) and single molecule fluorescence imaging. HIV expanded both under cell-free conditions with soluble receptor CD4 (sCD4) targeting the CD4 binding site on the HIV-1 envelope protein (Env) and when HIV binds to receptor on cellular membrane. We have shown that the HIV Env is needed to facilitate receptor induced virus size expansions, showing that the ‘lynchpin’ for size expansion is highly specific. We demonstrate that the size expansion required maturation of HIV and an internal capsid core with wild type stability, suggesting that different HIV compartments are linked and are involved in remodelling. Our work reveals a previously unknown event in HIV entry, and we propose that this pre-entry priming process enables HIV particles to facilitate the subsequent steps in infection. - Highlights: • Cell free viruses are able to receive external trigger that leads to apparent size expansion. • Virus envelope and CD4 receptor engagement is the lynchpin of virus size expansion. • Internal capsid organisation can influence receptor mediated virus size expansion. • Pre-existing virus-associated lipid membrane in cell free virus can accommodate the receptor mediated virus size expansion.

An organ-specific role for ethylene in rose petal expansion during dehydration and rehydration

Science.gov (United States)

Liu, Daofeng; Liu, Xiaojing; Meng, Yonglu; Sun, Cuihui; Tang, Hongshu; Jiang, Yudong; Khan, Muhammad Ali; Xue, Jingqi; Ma, Nan; Gao, Junping

2013-01-01

Dehydration is a major factor resulting in huge loss from cut flowers during transportation. In the present study, dehydration inhibited petal cell expansion and resulted in irregular flowers in cut roses, mimicking ethylene-treated flowers. Among the five floral organs, dehydration substantially elevated ethylene production in the sepals, whilst rehydration caused rapid and elevated ethylene levels in the gynoecia and sepals. Among the five ethylene biosynthetic enzyme genes (RhACS1–5), expression of RhACS1 and RhACS2 was induced by dehydration and rehydration in the two floral organs. Silencing both RhACS1 and RhACS2 significantly suppressed dehydration- and rehydration-induced ethylene in the sepals and gynoecia. This weakened the inhibitory effect of dehydration on petal cell expansion. β-glucuronidase activity driven by both the RhACS1 and RhACS2 promoters was dramatically induced in the sepals, pistil, and stamens, but not in the petals of transgenic Arabidopsis. This further supports the organ-specific induction of these two genes. Among the five rose ethylene receptor genes (RhETR1–5), expression of RhETR3 was predominantly induced by dehydration and rehydration in the petals. RhETR3 silencing clearly aggravated the inhibitory effect of dehydration on petal cell expansion. However, no significant difference in the effect between RhETR3-silenced flowers and RhETR-genes-silenced flowers was observed. Furthermore, RhETR-genes silencing extensively altered the expression of 21 cell expansion-related downstream genes in response to ethylene. These results suggest that induction of ethylene biosynthesis by dehydration proceeds in an organ-specific manner, indicating that ethylene can function as a mediator in dehydration-caused inhibition of cell expansion in rose petals. PMID:23599274

Direct and Indirect Effects of Five Factor Personality and Gender on Depressive Symptoms Mediated by Perceived Stress

Science.gov (United States)

Kim, Song E.; Cho, Juhee; Kwon, Min-Jung; Chang, Yoosoo; Ryu, Seungho; Shin, Hocheol

2016-01-01

This study was designed to investigate associations among five factor personality traits, perceived stress, and depressive symptoms and to examine the roles of personality and perceived stress in the relationship between gender and depressive symptoms. The participants (N = 3,950) were part of a cohort study for health screening and examination at the Kangbuk Samsung Hospital. Personality was measured with the Revised NEO Personality Inventory (NEO-PI-R). Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (CES-D). Perceived stress level was evaluated with a self-reported stress questionnaire developed for the Korea National Health and Nutrition Examination Survey. A higher degree of neuroticism and lower degrees of extraversion, agreeableness, and conscientiousness were significantly associated with greater perceived stress and depressive symptoms. Neuroticism and extraversion had significant direct and indirect effects (via stress as a mediator) on depressive symptoms in both genders. Agreeableness and conscientiousness had indirect effects on depression symptoms in both genders. Multiple mediation models were used to examine the mediational roles of each personality factor and perceived stress in the link between gender and depressive symptoms. Four of the personality factors (except openness) were significant mediators, along with stress, on the relationship between gender and depressive symptoms. Our findings suggest that the links between personality factors and depressive symptoms are mediated by perceived stress. As such, personality is an important factor to consider when examining the link between gender and depression. PMID:27120051

Direct and Indirect Effects of Five Factor Personality and Gender on Depressive Symptoms Mediated by Perceived Stress.

Science.gov (United States)

Kim, Song E; Kim, Han-Na; Cho, Juhee; Kwon, Min-Jung; Chang, Yoosoo; Ryu, Seungho; Shin, Hocheol; Kim, Hyung-Lae

2016-01-01

This study was designed to investigate associations among five factor personality traits, perceived stress, and depressive symptoms and to examine the roles of personality and perceived stress in the relationship between gender and depressive symptoms. The participants (N = 3,950) were part of a cohort study for health screening and examination at the Kangbuk Samsung Hospital. Personality was measured with the Revised NEO Personality Inventory (NEO-PI-R). Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (CES-D). Perceived stress level was evaluated with a self-reported stress questionnaire developed for the Korea National Health and Nutrition Examination Survey. A higher degree of neuroticism and lower degrees of extraversion, agreeableness, and conscientiousness were significantly associated with greater perceived stress and depressive symptoms. Neuroticism and extraversion had significant direct and indirect effects (via stress as a mediator) on depressive symptoms in both genders. Agreeableness and conscientiousness had indirect effects on depression symptoms in both genders. Multiple mediation models were used to examine the mediational roles of each personality factor and perceived stress in the link between gender and depressive symptoms. Four of the personality factors (except openness) were significant mediators, along with stress, on the relationship between gender and depressive symptoms. Our findings suggest that the links between personality factors and depressive symptoms are mediated by perceived stress. As such, personality is an important factor to consider when examining the link between gender and depression.

Parental bonding and depression: personality as a mediating factor.

Science.gov (United States)

Avagianou, Penelope-Alexia; Zafiropoulou, Maria

2008-01-01

According to Bowlby's theory of attachment, the role of early experience and parenting is of crucial importance to child development and mental health. In addition, several research findings suggest that parental bonding and different types of attachment play a crucial role in personality development. The present study examines the association between parental bonding experiences (lack of parental care, overprotection or both) and depression during adulthood. The objective of the present study was to evaluate different personality dimensions as possible mediators of the relation between perceptions of parental bonding and depressive symptoms in adult life. 181 participants (15- 49-years-old) completed the Parental Bonding Instrument (PBI), the Beck Depression Inventory (BDI) and the 16 Personality Factor Questionnaire (16PF). The results show that lack of parental care and overprotection is linked with depressive symptoms and a number of personality characteristics, such as low self-esteem, introversion, distress and emotional instability. In contrast, high care and low protection (optimal bonding) is linked with increased self-confidence, less distress and less depressive symptoms. The results presented here are in line with Bowlby's theory of attachment and show that parental bonding is linked with problematic personality development and psychopathology. The present study provided evidence that personality factors may mediate the observed relationship between parental rearing style and depression. The potential causal mechanisms warrant longitudinal evaluation.

Tissue factor pathway inhibitor for prediction of placenta-mediated adverse pregnancy outcomes in high-risk women: AngioPred study.

Directory of Open Access Journals (Sweden)

Aurélie Di Bartolomeo

Full Text Available The study aimed to evaluate if the rate of tissue factor pathway inhibitor during pregnancy and following delivery could be a predictive factor for placenta-mediated adverse pregnancy outcomes in high-risk women.This was a prospective multicentre cohort study of 200 patients at a high risk of occurrence or recurrence of placenta-mediated adverse pregnancy outcomes conducted between June 2008 and October 2010. Measurements of tissue factor pathway inhibitor resistance (normalized ratio and tissue factor pathway inhibitor activity were performed for the last 72 patients at 20, 24, 28, 32, and 36 weeks of gestation and during the postpartum period.Overall, 15 patients presented a placenta-mediated adverse pregnancy outcome. There was no difference in normalized tissue factor pathway inhibitor ratios between patients with and without placenta-mediated adverse pregnancy outcomes during pregnancy and in the post-partum period. Patients with placenta-mediated adverse pregnancy outcomes had tissue factor pathway inhibitor activity rates that were significantly higher than those in patients without at as early as 24 weeks of gestation. The same results were observed following delivery.Among high-risk women, the tissue factor pathway inhibitor activity of patients with gestational vascular complications is higher than that in other patients. Hence, these markers could augment a screening strategy that includes an analysis of angiogenic factors as well as clinical and ultrasound imaging with Doppler measurement of the uterine arteries.

Nitric oxide mediates angiogenesis induced in vivo by platelet-activating factor and tumor necrosis factor-alpha.

Science.gov (United States)

Montrucchio, G.; Lupia, E.; de Martino, A.; Battaglia, E.; Arese, M.; Tizzani, A.; Bussolino, F.; Camussi, G.

1997-01-01

We evaluated the role of an endogenous production of nitric oxide (NO) in the in vitro migration of endothelial cells and in the in vivo angiogenic response elicited by platelet-activating factor (PAF), tumor necrosis factor-alpha (TNF), and basic fibroblast growth factor (bFGF). The NO synthase inhibitor, N omega-nitro-L-arginine-methyl ester (L-NAME), but not its enantiomer D-NAME, prevented chemotaxis of endothelial cells induced in vitro by PAF and by TNF. The motogenic activity of TNF was also inhibited by WEB 2170, a specific PAF-receptor antagonist. In contrast, chemotaxis induced by bFGF was not prevented by L-NAME or by WEB 2170. Angiogenesis was studied in vivo in a murine model in which Matrigel was used as a vehicle for the delivery of mediators. In this model, the angiogenesis induced by PAF and TNF was inhibited by WEB 2170 and L-NAME but not by D-NAME. In contrast, angiogenesis induced by bFGF was not affected by L-NAME or by WEB 2170. TNF, but not bFGF, induced PAF synthesis within Matrigel. These results suggest that NO mediates the angiogenesis induced by PAF as well as that induced by TNF, which is dependent on the production of PAF. In contrast, the angiogenic effect of bFGF appears to be both PAF and NO independent. Images Figure 3 Figure 4 PMID:9250168

Essential roles of Gab1 tyrosine phosphorylation in growth factor-mediated signaling and angiogenesis.

Science.gov (United States)

Wang, Weiye; Xu, Suowen; Yin, Meimei; Jin, Zheng Gen

2015-02-15

Growth factors and their downstream receptor tyrosine kinases (RTKs) mediate a number of biological processes controlling cell function. Adaptor (docking) proteins, which consist exclusively of domains and motifs that mediate molecular interactions, link receptor activation to downstream effectors. Recent studies have revealed that Grb2-associated-binders (Gab) family members (including Gab1, Gab2, and Gab3), when phosphorylated on tyrosine residues, provide binding sites for multiple effector proteins, such as Src homology-2 (SH2)-containing protein tyrosine phosphatase 2 (SHP2) and phosphatidylinositol 3-kinase (PI3K) regulatory subunit p85, thereby playing important roles in transducing RTKs-mediated signals into pathways with diversified biological functions. Here, we provide an up-to-date overview on the domain structure and biological functions of Gab1, the most intensively studied Gab family protein, in growth factor signaling and biological functions, with a special focus on angiogenesis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Supersonic expansion of argon into vacuum

Energy Technology Data Exchange (ETDEWEB)

Habets, A H.M.

1977-01-21

A theoretical description of a free supersonic expansion process is given. Three distinct regions in the expansion are discussed, namely the continuum region, the gradual transition to the collisionless regime, and the free-molecular-flow stage. Important topics are the peaking-factor formalism, the thermal-conduction model, and the virtual-source formalism. The formation of the molecular beam from the expansion and condensation phenomena occurring in the expanding gas are discussed. The molecular beam machine used in the measurements is described and special attention is given to the cryopumps used in the supersonic sources as well as to the time-of-flight analysis of the molecular beam velocity distributions. Finally, the processing of experimental data is discussed, particularly the least-squares determination of best-fit representations of the measurements.

Supersonic expansion of argon into vacuum

International Nuclear Information System (INIS)

Habets, A.H.M.

1977-01-01

A theoretical description of a free supersonic expansion process is given. Three distinct regions in the expansion are discussed, namely the continuum region, the gradual transition to the collisionless regime, and the free-molecular-flow stage. Important topics are the peaking-factor formalism, the thermal-conduction model, and the virtual-source formalism. The formation of the molecular beam from the expansion and condensation phenomena occurring in the expanding gas are discussed. The molecular beam machine used in the measurements is described and special attention is given to the cryopumps used in the supersonic sources as well as to the time-of-flight analysis of the molecular beam velocity distributions. Finally, the processing of experimental data is discussed, particularly the least-squares determination of best-fit representations of the measurements

Epidermal Growth Factor Enhances Cellular Uptake of Polystyrene Nanoparticles by Clathrin-Mediated Endocytosis.

Science.gov (United States)

Phuc, Le Thi Minh; Taniguchi, Akiyoshi

2017-06-19

The interaction between nanoparticles and cells has been studied extensively, but most research has focused on the effect of various nanoparticle characteristics, such as size, morphology, and surface charge, on the cellular uptake of nanoparticles. In contrast, there have been very few studies to assess the influence of cellular factors, such as growth factor responses, on the cellular uptake efficiency of nanoparticles. The aim of this study was to clarify the effects of epidermal growth factor (EGF) on the uptake efficiency of polystyrene nanoparticles (PS NPs) by A431 cells, a human carcinoma epithelial cell line. The results showed that EGF enhanced the uptake efficiency of A431 cells for PS NPs. In addition, inhibition and localization studies of PS NPs and EGF receptors (EGFRs) indicated that cellular uptake of PS NPs is related to the binding of EGF-EGFR complex and PS NPs. Different pathways are used to enter the cells depending on the presence or absence of EGF. In the presence of EGF, cellular uptake of PS NPs is via clathrin-mediated endocytosis, whereas, in the absence of EGF, uptake of PS NPs does not involve clathrin-mediated endocytosis. Our findings indicate that EGF enhances cellular uptake of PS NPs by clathrin-mediated endocytosis. This result could be important for developing safe nanoparticles and their safe use in medical applications.

Epidermal Growth Factor Enhances Cellular Uptake of Polystyrene Nanoparticles by Clathrin-Mediated Endocytosis

Directory of Open Access Journals (Sweden)

Le Thi Minh Phuc

2017-06-01

Full Text Available The interaction between nanoparticles and cells has been studied extensively, but most research has focused on the effect of various nanoparticle characteristics, such as size, morphology, and surface charge, on the cellular uptake of nanoparticles. In contrast, there have been very few studies to assess the influence of cellular factors, such as growth factor responses, on the cellular uptake efficiency of nanoparticles. The aim of this study was to clarify the effects of epidermal growth factor (EGF on the uptake efficiency of polystyrene nanoparticles (PS NPs by A431 cells, a human carcinoma epithelial cell line. The results showed that EGF enhanced the uptake efficiency of A431 cells for PS NPs. In addition, inhibition and localization studies of PS NPs and EGF receptors (EGFRs indicated that cellular uptake of PS NPs is related to the binding of EGF–EGFR complex and PS NPs. Different pathways are used to enter the cells depending on the presence or absence of EGF. In the presence of EGF, cellular uptake of PS NPs is via clathrin-mediated endocytosis, whereas, in the absence of EGF, uptake of PS NPs does not involve clathrin-mediated endocytosis. Our findings indicate that EGF enhances cellular uptake of PS NPs by clathrin-mediated endocytosis. This result could be important for developing safe nanoparticles and their safe use in medical applications.

Characterizing Factors Associated with Built-Up Land Expansion in Urban and Non-Urban Areas from a Morphological Perspective

Directory of Open Access Journals (Sweden)

Zhonghao Zhang

2017-08-01

Full Text Available In this paper, built-up land expansion patterns and the associated factors were characterized in urban and non-urban areas across the Wen-Tai region of eastern China. Fractal dimension can be used as a reliable indicator of the complexity of built-up land form, and the increasing trend of fractal dimension indicated a more complex, dispersed pattern of built-up land in urban areas. Spatial regression models were quantitatively implemented to identify the indicators influencing the variation of fractal dimensions. Our findings suggested that the fractal dimension of built-up land forms was positively correlated to the patch density and elevation when built-up land expansion was more concentrated. Both landscape shape index and Gross Domestic Product (GDP were positively correlated with fractal dimension in urban areas, and total edge, edge density, and connective index had impacts on fractal dimension in non-urban areas. Slope and agricultural population also showed an influence on fractal dimension. This study provided a new way for urban studies in interpreting the complex interactions between fractal dimension and related factors. The combined approach of fractal dimension and spatial analysis can provide the government planners with valuable information that can be efficiently used to realize the influences of land use policies in urban and non-urban areas.

The Economic Impact of Medicaid Expansion on Pennsylvania.

Science.gov (United States)

Price, Carter C; Donohue, Julie M; Saltzman, Evan; Woods, Dulani; Eibner, Christine

2013-01-01

The Affordable Care Act is a substantial reform of the U.S. health care insurance system. Using the RAND COMPARE model, researchers assessed the act's potential economic effects on Pennsylvania, factoring in an optional expansion of Medicaid, and found the state would enjoy significant net benefits. With or without the expansion of Medicaid, the act will increase insurance coverage to hundreds of thousands of Pennsylvanians, but the COMPARE model estimates that the expansion of Medicaid eligibility would cover an additional 350,000 people and bring more than $2 billion in federal spending into the state annually than if the state did not expand. Should the state expand Medicaid, the additional spending will add more than $3 billion a year to the state's GDP and support 35,000 jobs. But Medicaid expansion is not without cost for the state; the estimated cumulative effect on Pennsylvania's Medicaid spending will be $180 million higher with the expansion than without between 2014 and 2020. Substantial reductions in uncompensated care costs for hospitals are possible even without expansion, but savings to hospitals for uncompensated care funding are even larger with the Medicaid expansion, amounting to $550 million or more each year.

Simplified Technique for Predicting Offshore Pipeline Expansion

Science.gov (United States)

Seo, J. H.; Kim, D. K.; Choi, H. S.; Yu, S. Y.; Park, K. S.

2018-06-01

In this study, we propose a method for estimating the amount of expansion that occurs in subsea pipelines, which could be applied in the design of robust structures that transport oil and gas from offshore wells. We begin with a literature review and general discussion of existing estimation methods and terminologies with respect to subsea pipelines. Due to the effects of high pressure and high temperature, the production of fluid from offshore wells is typically caused by physical deformation of subsea structures, e.g., expansion and contraction during the transportation process. In severe cases, vertical and lateral buckling occurs, which causes a significant negative impact on structural safety, and which is related to on-bottom stability, free-span, structural collapse, and many other factors. In addition, these factors may affect the production rate with respect to flow assurance, wax, and hydration, to name a few. In this study, we developed a simple and efficient method for generating a reliable pipe expansion design in the early stage, which can lead to savings in both cost and computation time. As such, in this paper, we propose an applicable diagram, which we call the standard dimensionless ratio (SDR) versus virtual anchor length (L A ) diagram, that utilizes an efficient procedure for estimating subsea pipeline expansion based on applied reliable scenarios. With this user guideline, offshore pipeline structural designers can reliably determine the amount of subsea pipeline expansion and the obtained results will also be useful for the installation, design, and maintenance of the subsea pipeline.

Megakaryocytes promote murine osteoblastic HSC niche expansion and stem cell engraftment after radioablative conditioning.

Science.gov (United States)

Olson, Timothy S; Caselli, Anna; Otsuru, Satoru; Hofmann, Ted J; Williams, Richard; Paolucci, Paolo; Dominici, Massimo; Horwitz, Edwin M

2013-06-27

Successful hematopoietic stem cell (HSC) transplantation requires donor HSC engraftment within specialized bone marrow microenvironments known as HSC niches. We have previously reported a profound remodeling of the endosteal osteoblastic HSC niche after total body irradiation (TBI), defined as relocalization of surviving megakaryocytes to the niche site and marked expansion of endosteal osteoblasts. We now demonstrate that host megakaryocytes function critically in expansion of the endosteal niche after preparative radioablation and in the engraftment of donor HSC. We show that TBI-induced migration of megakaryocytes to the endosteal niche depends on thrombopoietin signaling through the c-MPL receptor on megakaryocytes, as well as CD41 integrin-mediated adhesion. Moreover, niche osteoblast proliferation post-TBI required megakaryocyte-secreted platelet-derived growth factor-BB. Furthermore, blockade of c-MPL-dependent megakaryocyte migration and function after TBI resulted in a significant decrease in donor HSC engraftment in primary and competitive secondary transplantation assays. Finally, we administered thrombopoietin to mice beginning 5 days before marrow radioablation and ending 24 hours before transplant to enhance megakaryocyte function post-TBI, and found that this strategy significantly enhanced donor HSC engraftment, providing a rationale for improving hematopoietic recovery and perhaps overall outcome after clinical HSC transplantation.

Operator expansion in σ-model

International Nuclear Information System (INIS)

Terent'ev, M.V.

1986-01-01

The operator expansion is studied in two dimensional σ-model with O(N) symmetry group at large values of N for the Green function at x 2 → 0 (Here n(x) is the dynamical field of σ-model). As a preliminary step the renormalization scheme is formulated in framework of I/N expansion where the intermediate scale μ 2 is introdused and regions of large (p > μ) and small (p 2 )/N in composite operators (here f(μ 2 ) is the effective coupling constant at the point μ 2 ) and the corrections of order of m 2 x 2 f(μ 2 )/N in the coefficient functions (here m is the dynamical mass-scale factor of σ-model) decisively depend on the recipe of factorization of small and large momenta regions. Due to the analogy between σ-model and quantum chromodynamics (QCD) the obtained result indicates the theoretical limitations to the accuracy of sum rule method in QCD

Co-factors necessary for PPAR mediated transactivation of endogenous target genes

DEFF Research Database (Denmark)

Grøntved, Lars; Nielsen, Ronni; Stunnenberg, Henk

of endogenous target gene in different cell types are elusive. To mutually compare the ability of the PPAR subtypes to activate endogenous target genes in a given cell, PPARa, PPARb/d and PPARg2 were HA tagged and rapidly, equally and synchronously expressed using adenoviral delivery. Within a few hours after...... subtype specific activation of target genes. Accumulating evidence suggests that transcriptional co-factors can function as master regulators for nuclear receptors and impose promoter selectivity. To study co-factor necessity for PPAR mediated transactivation of endogenous target genes, specific co...

IL-2-Mediated In Vivo Expansion of Regulatory T Cells Combined with CD154–CD40 Co-Stimulation Blockade but Not CTLA-4 Ig Prolongs Allograft Survival in Naive and Sensitized Mice

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Dela Golshayan

2017-04-01

Full Text Available In recent years, regulatory T cells (Treg-based immunotherapy has emerged as a promising strategy to promote operational tolerance after solid organ transplantation (SOT. However, a main hurdle for the therapeutic use of Treg in transplantation is their low frequency, particularly in non-lymphopenic hosts. We aimed to expand Treg directly in vivo and determine their efficacy in promoting donor-specific tolerance, using a stringent experimental model. Administration of the IL-2/JES6-1 immune complex at the time of transplantation resulted in significant expansion of donor-specific Treg, which suppressed alloreactive T cells. IL-2-mediated Treg expansion in combination with short-term CD154–CD40 co-stimulation blockade, but not CTLA-4 Ig or rapamycin, led to tolerance to MHC-mismatched skin grafts in non-lymphopenic mice, mainly by hindering alloreactive CD8+ effector T cells and the production of alloantibodies. Importantly, this treatment also allowed prolonged survival of allografts in the presence of either donor-specific or cross-reactive memory cells. However, late rejection occurred in sensitized hosts, partly mediated by activated B cells. Overall, these data illustrate the potential but also some important limitations of Treg-based therapy in clinical SOT as well as the importance of concomitant immunomodulatory strategies in particular in sensitized hosts.

Mediating and Marketing Factors Influence the Prescription Behavior of Physicians: An Empirical Investigation

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Rizwan Raheem Ahmed

2016-02-01

Full Text Available The authors present general review of the literature and the results of an empirical research on the subject. A cross-sectional questionnaire-based survey was conducted, being answered by 350 respondents: mix of graduate and post graduate doctors of private and public hospitals of Karachi City, and pharmaceutical personnel (mix of sales and marketing of national and multinational pharmaceutical companies operating in Pakistan. To test hypothesis, structural equation modelling (SEM was employed using AMOS 7 software package. As data are normally distributed, maximum likelihood method of estimation was used. Factorial ANOVA also enables us to examine the interaction effect between the factors. The results from factorial ANOVA test all the hypotheses of model, and results were declared significant at p <0.05. Findings are interesting as they establish association between variables (scientific literatures, promotional material, regular follow up, CMEs & conferences, personalized activities and prescription behavior of doctors mediated by strong phenomenon of medical representative PR and brand image of a company/product in changing the prescription behavior of doctors. Based on the results of this study, the pharmaceutical companies can device better marketing strategies keeping in view of these mediating effects. The article presents only two mediating and five marketing factors, whereas, more marketing and mediating variables can be added and tested, so, in future this gape can be overcome by other researchers. Moreover, a larger sample size could be applied and the scope of study can be enhanced.

Correlations between Socioeconomic Drivers and Indicators of Urban Expansion: Evidence from the Heavily Urbanised Shanghai Metropolitan Area, China

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Jinghui Li

2017-07-01

Full Text Available Rapid urban expansion resulting in increased impervious surfaces causes a series of urban environmental problems, e.g., the urban heat island and urban forest fragmentation. Urban expansion is a serious threat to human quality of life and living environments. It has been studied from a variety of aspects, but its driving factors and time series expansion characteristics (i.e., expansion intensity, pattern and direction need to be better explained in order to devise more effective management strategies. This study examined how social and economic factors are linked in driving urban expansion. Based on multi-temporal aerial images, a rapid urban expansion period, 2000–2010, in Shanghai was analysed. The urban area expanded from 1770.36 to 2855.44 km2 in the period, with a mean annual expansion rate of 108.51 km2. Urban expansion in 2000–2005 (40.42% was much faster than in 2005–2010 (14.86%, and its direction was southeast, southwest and south. The main pattern was edge expansion in both sub-periods. Social factors, especially population density, significantly affected urban expansion. These findings can help understand the urban expansion process and its driving factors, which has important implications for urban planning and management in Shanghai and similar cities.

Residues 39-56 of Stem Cell Factor Protein Sequence Are Capable of Stimulating the Expansion of Cord Blood CD34+ Cells.

Science.gov (United States)

Shen, Bin; Jiang, Wenhong; Fan, Jie; Dai, Wei; Ding, Xinxin; Jiang, Yongping

2015-01-01

Stem cell factor (SCF) can stimulate hematopoietic stem cell (HSC) expansion; however, the specific structural region(s) of SCF protein that are critical for this function are still unknown. A novel monoclonal antibody (named 23C8) against recombinant human SCF (rhSCF) was previously found to inhibit the ability of rhSCF to enhance HSC expansion, making it possible to identify the relevant active region to HSC. Eleven polypeptides were synthesized, which were designed to cover the full-length of rhSCF, with overlaps that are at least 3 amino acids long. ELISA was used to identify the polypeptide(s) that specifically react with the anti-SCF. The effects of the synthetic polypeptides on human HSC expansion, or on the ability of the full-length rhSCF to stimulate cell proliferation, were evaluated ex vivo. Total cell number was monitored using hemocytometer whereas CD34+ cell number was calculated based on the proportion determined via flow cytometry on day 6 of culture. Of all polypeptides analyzed, only one, named P0, corresponding to the SCF protein sequence at residues 39-56, was recognized by 23C8 mAb during ELISA. P0 stimulated the expansion of CD34+ cells derived from human umbilical cord blood (UCB). Addition of P0 increased the numbers of total mononucleated cells and CD34+ cells, by ~2 fold on day 6. P0 also showed partial competition against full-length rhSCF in the ex vivo cell expansion assay. Residues 39-56 of rhSCF comprise a critical functional region for its ability to enhance expansion of human UCB CD34+ cells. The peptide P0 is a potential candidate for further development as a synthetic substitute for rhSCF in laboratory and clinical applications.

Adolescent-Parent Attachment and Externalizing Behavior: The Mediating Role of Individual and Social Factors.

Science.gov (United States)

de Vries, Sanne L A; Hoeve, Machteld; Stams, Geert Jan J M; Asscher, Jessica J

2016-02-01

The aim of this study was to test whether the associations between adolescent-parent attachment and externalizing problem behavior of adolescents were mediated by adolescent cognitive distortions, self-esteem, parental monitoring and association with deviant peers. A total of 102 adolescents (71 % male; aged 12-19 years) at risk for developing delinquent behaviors reported on attachment, parental monitoring, aggressive and delinquent behavior and peers. Mediation effects were tested by using structural equation modeling. Different pathways were found depending on the type of externalizing behavior. The association between attachment and direct and indirect aggressive behavior was mediated by cognitive distortions. The relation between attachment and delinquency was mediated by deviant peers and parental monitoring. We argue that clinical practice should focus on the attachment relationship between adolescent and parents in order to positively affect risk and protective factors for adolescents' aggressive and delinquent behavior.

Comparison of the unitary pole and Adhikari-Sloan expansions in the three nucleon system

International Nuclear Information System (INIS)

Afnan, I.R.; Birrell, N.D.

1977-01-01

The binding energy of 3 H, percentage S-, S'- and D-state probability, and charge form factor of 3 He are calculated using the unitary pole and Adhikari-Sloan separable expansions to the Reid soft core potential. Comparison of the results for the two separable expansions show that the expansion of Adhikari and Sloan has the better convergence property, and the lowest rank expansion considered (equivalent to the unitary pole approximation) gives a good approximation to the binding energy of 3 H and the charge form factor of 3 He, even at large momentum transfer (K 2 -2 ). (Author)

Evidence for Multiple Mediator Complexes in Yeast Independently Recruited by Activated Heat Shock Factor.

Science.gov (United States)

Anandhakumar, Jayamani; Moustafa, Yara W; Chowdhary, Surabhi; Kainth, Amoldeep S; Gross, David S

2016-07-15

Mediator is an evolutionarily conserved coactivator complex essential for RNA polymerase II transcription. Although it has been generally assumed that in Saccharomyces cerevisiae, Mediator is a stable trimodular complex, its structural state in vivo remains unclear. Using the "anchor away" (AA) technique to conditionally deplete select subunits within Mediator and its reversibly associated Cdk8 kinase module (CKM), we provide evidence that Mediator's tail module is highly dynamic and that a subcomplex consisting of Med2, Med3, and Med15 can be independently recruited to the regulatory regions of heat shock factor 1 (Hsf1)-activated genes. Fluorescence microscopy of a scaffold subunit (Med14)-anchored strain confirmed parallel cytoplasmic sequestration of core subunits located outside the tail triad. In addition, and contrary to current models, we provide evidence that Hsf1 can recruit the CKM independently of core Mediator and that core Mediator has a role in regulating postinitiation events. Collectively, our results suggest that yeast Mediator is not monolithic but potentially has a dynamic complexity heretofore unappreciated. Multiple species, including CKM-Mediator, the 21-subunit core complex, the Med2-Med3-Med15 tail triad, and the four-subunit CKM, can be independently recruited by activated Hsf1 to its target genes in AA strains. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Linear expansion of products out of thermal splitting graphite

International Nuclear Information System (INIS)

Tishina, E.A.; Kurnevich, G.I.

1994-01-01

Linear expansion of thermally split graphite in the form of foil and pressed items of different density was studied. It is ascertained that the extreme character of temperature dependence of linear expansion factor of pressed samples of thermally split graphite is determined by the formation of closed pores containing air in the course of their production. 3 refs., 2 figs

Is thrombophilia a risk factor for placenta-mediated pregnancy complications?

DEFF Research Database (Denmark)

Hoffmann, Elise; Hedlund, Elisabeth; Perin, Trine

2012-01-01

PURPOSE: To determine if thrombophilia is a risk factor for placenta-mediated pregnancy complications (PMPC) (i.e., preeclampsia, intrauterine growth restriction (IUGR), placental abruption, intrauterine fetal death and recurrent pregnancy loss). METHODS: A 5-year retrospective cohort study....... Ongoing pregnancies in women with an antecedent PMPC with thrombophilia were compared with the pregnancies in similar women without thrombophilia. The main outcome measures were mean birth weight deviations, corrected for gestational age, and recurrence of PMPC. Low-molecular-weight heparin (LMWH...

Two-Body Orbit Expansion Due to Time-Dependent Relative Acceleration Rate of the Cosmological Scale Factor

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Lorenzo Iorio

2014-01-01

Full Text Available By phenomenologically assuming a slow temporal variation of the percent acceleration rate S̈S -1 of the cosmic scale factor S(t, it is shown that the orbit of a local binary undergoes a secular expansion. To first order in the power expansion of S̈S -1 around the present epoch t0, a non-vanishing shift per orbit (Δr of the two-body relative distance r occurs for eccentric trajectories. A general relativistic expression, which turns out to be cubic in the Hubble parameter H0 at the present epoch, is explicitly calculated for it in the case of matter-dominated epochs with Dark Energy. For a highly eccentric Oort comet orbit with period Pb ≈ 31 Myr, the general relativistic distance shift per orbit turns out to be of the order of (Δr ≈ 70 km. For the Large Magellanic Cloud, assumed on a bound elliptic orbit around the Milky Way, the shift per orbit is of the order of (Δr ≈ 2–4 pc. Our result has a general validity since it holds in any cosmological model admitting the Hubble law and a slowly varying S̈S-1(t. More generally, it is valid for an arbitrary Hooke-like extra-acceleration whose “elastic” parameter κ is slowly time-dependent, irrespectively of the physical mechanism which may lead to it. The coefficient κ1 of the first-order term of the power expansion of κ(t can be preliminarily constrained in a model-independent way down to a κ1 ≲ 2 x 10-13 year-3 level from latest Solar System’s planetary observations. The radial velocities of the double lined spectroscopic binary ALPHA Cen AB yield κ1 ≲ 10-8 year-3.

Personality, Political Attitudes and Participation in Protests: The Direct and Mediated Effects of Psychological Factors on Political Activism

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Ednaldo Aparecido Ribeiro

2016-12-01

Full Text Available Studies combining psychology and political science have shown that personality traits such as extroversion and openness to experiences are conditioning factors of political activism. However, the mechanisms through which this effect occurs are still poorly understood. Aiming to advance this topic, this article presents the results of an investigation that looked to analyse the mediated effects of personality traits in the Brazilian context, taking as mediating conditioning factors various attitudes and subjective dispositions commonly found in the literature, such as interest in politics and subjective political efficacy. Using the Latin American Public Opinion Project data, the hypothesis was tested that personality influences behaviour, since it favours the development of a number of attitudes that function as basic factors conditioning civic engagement. The results indicate the significant mediated effects of extroversion and openness to experience, especially with regard to political knowledge.

Do material, psychosocial and behavioural factors mediate the relationship between disability acquisition and mental health? A sequential causal mediation analysis.

Science.gov (United States)

Aitken, Zoe; Simpson, Julie Anne; Gurrin, Lyle; Bentley, Rebecca; Kavanagh, Anne Marie

2018-01-29

There is evidence of a causal relationship between disability acquisition and poor mental health; however, the mechanism by which disability affects mental health is poorly understood. This gap in understanding limits the development of effective interventions to improve the mental health of people with disabilities. We used four waves of data from the Household, Income and Labour Dynamics in Australia Survey (2011-14) to compare self-reported mental health between individuals who acquired any disability (n=387) and those who remained disability-free (n=7936). We tested three possible pathways from disability acquisition to mental health, examining the effect of material, psychosocial and behavioural mediators. The effect was partitioned into natural direct and indirect effects through the mediators using a sequential causal mediation analysis approach. Multiple imputation using chained equations was used to assess the impact of missing data. Disability acquisition was estimated to cause a five-point decline in mental health [estimated mean difference: -5.3, 95% confidence interval (CI) -6.8, -3.7]. The indirect effect through material factors was estimated to be a 1.7-point difference (-1.7, 95% CI -2.8, -0.6), explaining 32% of the total effect, with a negligible proportion of the effect explained by the addition of psychosocial characteristics (material and psychosocial: -1.7, 95% CI -3.0, -0.5) and a further 5% by behavioural factors (material-psychosocial-behavioural: -2.0, 95% CI -3.4, -0.6). The finding that the effect of disability acquisition on mental health operates predominantly through material rather than psychosocial and behavioural factors has important implications. The results highlight the need for better social protection, including income support, employment and education opportunities, and affordable housing for people who acquire a disability. © The Author(s) 2018; all rights reserved. Published by Oxford University Press on behalf of the

Convergence of the multiple scattering expansion in XAFS and XANES

International Nuclear Information System (INIS)

Rehr, J.J.

1992-01-01

The convergence of the multiple-scattering expansion of XAFS and XANES by explicit path-bypath calculations. The approach is based on the fast scattering matrix formalism of Rehr and Albers, together with an automated path finder and filters that exclude negligible paths. High-order scattering terms are found to be essential, especially at low energies. Several factors including the magnitude of curved wave scattering amplitudes, inelastic losses and multiple-scattering Debye-Waller factors control convergence of the expansion. The convergence is illustrated explicitly for the case of diatomic molecules

Developing an Agent-Based Model to Simulate Urban Land-Use Expansion (Case Study: Qazvin)

OpenAIRE

F. Nourian; A. A. Alesheikh; F. Hosseinali

2012-01-01

Extended abstract1-IntroductionUrban land-use expansion is a challenging issue in developing countries. Increases in population as well as the immigration from the villages to the cities are the two major factors for that phenomenon. Those factors have reduced the influence of efforts that try to limit the cities’ boundaries. Thus, spatial planners always look for the models that simulate the expansion of urban land-uses and enable them to prevent unbalanced expansions of cities and guide the...

Transcription-factor-mediated DNA looping probed by high-resolution, single-molecule imaging in live E. coli cells.

Directory of Open Access Journals (Sweden)

Zach Hensel

Full Text Available DNA looping mediated by transcription factors plays critical roles in prokaryotic gene regulation. The "genetic switch" of bacteriophage λ determines whether a prophage stays incorporated in the E. coli chromosome or enters the lytic cycle of phage propagation and cell lysis. Past studies have shown that long-range DNA interactions between the operator sequences O(R and O(L (separated by 2.3 kb, mediated by the λ repressor CI (accession number P03034, play key roles in regulating the λ switch. In vitro, it was demonstrated that DNA segments harboring the operator sequences formed loops in the presence of CI, but CI-mediated DNA looping has not been directly visualized in vivo, hindering a deep understanding of the corresponding dynamics in realistic cellular environments. We report a high-resolution, single-molecule imaging method to probe CI-mediated DNA looping in live E. coli cells. We labeled two DNA loci with differently colored fluorescent fusion proteins and tracked their separations in real time with ∼40 nm accuracy, enabling the first direct analysis of transcription-factor-mediated DNA looping in live cells. Combining looping measurements with measurements of CI expression levels in different operator mutants, we show quantitatively that DNA looping activates transcription and enhances repression. Further, we estimated the upper bound of the rate of conformational change from the unlooped to the looped state, and discuss how chromosome compaction may impact looping kinetics. Our results provide insights into transcription-factor-mediated DNA looping in a variety of operator and CI mutant backgrounds in vivo, and our methodology can be applied to a broad range of questions regarding chromosome conformations in prokaryotes and higher organisms.

Parallel Expansions of Sox Transcription Factor Group B Predating the Diversifications of the Arthropods and Jawed Vertebrates

Science.gov (United States)

Zhong, Lei; Wang, Dengqiang; Gan, Xiaoni; Yang, Tong; He, Shunping

2011-01-01

Group B of the Sox transcription factor family is crucial in embryo development in the insects and vertebrates. Sox group B, unlike the other Sox groups, has an unusually enlarged functional repertoire in insects, but the timing and mechanism of the expansion of this group were unclear. We collected and analyzed data for Sox group B from 36 species of 12 phyla representing the major metazoan clades, with an emphasis on arthropods, to reconstruct the evolutionary history of SoxB in bilaterians and to date the expansion of Sox group B in insects. We found that the genome of the bilaterian last common ancestor probably contained one SoxB1 and one SoxB2 gene only and that tandem duplications of SoxB2 occurred before the arthropod diversification but after the arthropod-nematode divergence, resulting in the basal repertoire of Sox group B in diverse arthropod lineages. The arthropod Sox group B repertoire expanded differently from the vertebrate repertoire, which resulted from genome duplications. The parallel increases in the Sox group B repertoires of the arthropods and vertebrates are consistent with the parallel increases in the complexity and diversification of these two important organismal groups. PMID:21305035

Thermal expansion

International Nuclear Information System (INIS)

Yun, Y.

2015-01-01

Thermal expansion of fuel pellet is an important property which limits the lifetime of the fuels in reactors, because it affects both the pellet and cladding mechanical interaction and the gap conductivity. By fitting a number of available measured data, recommended equations have been presented and successfully used to estimate thermal expansion coefficient of the nuclear fuel pellet. However, due to large scatter of the measured data, non-consensus data have been omitted in formulating the equations. Also, the equation is strongly governed by the lack of appropriate experimental data. For those reasons, it is important to develop theoretical methodologies to better describe thermal expansion behaviour of nuclear fuel. In particular, first-principles and molecular dynamics simulations have been certainly contributed to predict reliable thermal expansion without fitting the measured data. Furthermore, the two theoretical techniques have improved on understanding the change of fuel dimension by describing the atomic-scale processes associated with lattice expansion in the fuels. (author)

A meta-analysis of global urban land expansion.

Science.gov (United States)

Seto, Karen C; Fragkias, Michail; Güneralp, Burak; Reilly, Michael K

2011-01-01

The conversion of Earth's land surface to urban uses is one of the most irreversible human impacts on the global biosphere. It drives the loss of farmland, affects local climate, fragments habitats, and threatens biodiversity. Here we present a meta-analysis of 326 studies that have used remotely sensed images to map urban land conversion. We report a worldwide observed increase in urban land area of 58,000 km(2) from 1970 to 2000. India, China, and Africa have experienced the highest rates of urban land expansion, and the largest change in total urban extent has occurred in North America. Across all regions and for all three decades, urban land expansion rates are higher than or equal to urban population growth rates, suggesting that urban growth is becoming more expansive than compact. Annual growth in GDP per capita drives approximately half of the observed urban land expansion in China but only moderately affects urban expansion in India and Africa, where urban land expansion is driven more by urban population growth. In high income countries, rates of urban land expansion are slower and increasingly related to GDP growth. However, in North America, population growth contributes more to urban expansion than it does in Europe. Much of the observed variation in urban expansion was not captured by either population, GDP, or other variables in the model. This suggests that contemporary urban expansion is related to a variety of factors difficult to observe comprehensively at the global level, including international capital flows, the informal economy, land use policy, and generalized transport costs. Using the results from the global model, we develop forecasts for new urban land cover using SRES Scenarios. Our results show that by 2030, global urban land cover will increase between 430,000 km(2) and 12,568,000 km(2), with an estimate of 1,527,000 km(2) more likely.

Epidermal growth factor-mediated effects on equine vascular smooth muscle cells

International Nuclear Information System (INIS)

Grosenbaugh, D.A.; Amoss, M.S.; Hood, D.M.; Morgan, S.J.; Williams, J.D.

1988-01-01

Epidermal growth factor (EGF) receptor binding kinetics and EGF-mediated stimulation of DNA synthesis and cellular proliferation were studied in cultured vascular smooth muscle cells (VSMC) from the equine thoracic aorta. Binding studies, using murine 125 I-labeled EGF, indicate the presence of a single class of high-affinity binding sites, with an estimated maximal binding capacity of 5,800 sites/cells. EGF stimulated [ 3 H]thymidine uptake in confluent quiescent monolayers in a dose-dependent fashion, half-maximal stimulation occurring at 7.5 x 10 -11 M. Likewise, EGF-mediated cellular proliferation was dose dependent under reduced serum concentrations. Equine VSMC contain specific receptors for EGF, and EGF can stimulate DNA synthesis and proliferation in these cultured cells, which suggests that EGF may participate in the proliferative changes observed in equine distal digital peripheral vascular disease

Low-temperature thermal expansion

International Nuclear Information System (INIS)

Collings, E.W.

1986-01-01

This chapter discusses the thermal expansion of insulators and metals. Harmonicity and anharmonicity in thermal expansion are examined. The electronic, magnetic, an other contributions to low temperature thermal expansion are analyzed. The thermodynamics of the Debye isotropic continuum, the lattice-dynamical approach, and the thermal expansion of metals are discussed. Relative linear expansion at low temperatures is reviewed and further calculations of the electronic thermal expansion coefficient are given. Thermal expansions are given for Cu, Al and Ti. Phenomenologic thermodynamic relationships are also discussed

Towards an expansive hybrid psychology: integrating theories of the mediated mind.

Science.gov (United States)

Brinkmann, Svend

2011-03-01

This article develops an integrative theory of the mind by examining how the mind, understood as a set of skills and dispositions, depends upon four sources of mediators. Harré's hybrid psychology is taken as a meta-theoretical starting point, but is expanded significantly by including the four sources of mediators that are the brain, the body, social practices and technological artefacts. It is argued that the mind is normative in the sense that mental processes do not simply happen, but can be done more or less well, and thus are subject to normative appraisal. The expanded hybrid psychology is meant to assist in integrating theoretical perspectives and research interests that are often thought of as incompatible, among them neuroscience, phenomenology of the body, social practice theory and technology studies. A main point of the article is that these perspectives each are necessary for an integrative approach to the human mind.

Renormalizations and operator expansion in sigma model

International Nuclear Information System (INIS)

Terentyev, M.V.

1988-01-01

The operator expansion (OPE) is studied for the Green function at x 2 → 0 (n(x) is the dynamical field ofσ-model) in the framework of the two-dimensional σ-model with the O(N) symmetry group at large N. As a preliminary step we formulate the renormalization scheme which permits introduction of an arbitrary intermediate scale μ 2 in the framework of 1/N expansion and discuss factorization (separation) of small (p μ) momentum region. It is shown that definition of composite local operators and coefficient functions figuring in OPE is unambiguous only in the leading order in 1/N expansion when dominant are the solutions with extremum of action. Corrections of order f(μ 2 )/N (here f(μ 2 ) is the effective interaction constant at the point μ 2 ) in composite operators and coefficient functions essentially depend on factorization method of high and low momentum regions. It is shown also that contributions to the power corrections of order m 2 x 2 f(μ 2 )/N in the Green function (here m is the dynamical mass-scale factor in σ-model) arise simultaneously from two sources: from the mean vacuum value of the composite operator n ∂ 2 n and from the hard particle contributions in the coefficient function of unite operator. Due to the analogy between σ-model and QCD the obtained result indicates theoretical limitations to the sum rule method in QCD. (author)

A pilot study of self-esteem as a mediator between family factors and depressive symptoms in young adult university students.

Science.gov (United States)

Restifo, Kathleen; Akse, Joyce; Guzman, Natalie Valle; Benjamins, Caroline; Dick, Katharina

2009-03-01

The aim of this study was to examine whether self-esteem mediates the relationship between family factors and depressive symptoms in young adults. Participants completed self-report questionnaires about overall family environment, conflict with mother or father, parental rearing, self esteem, and depressive symptoms. Self-esteem was found to mediate the relationship between the combined family factors and depressive symptoms. When examined simultaneously, none of the individual family variables uniquely predicted depressive symptoms or self-esteem. However, separate analysis of each of the three family factors provided evidence for self-esteem mediating the relationship between parental conflict and depressive symptoms, and the relationship between parental care and depressive symptoms. Self-esteem may play a role in the mechanism underlying the link between parent-offspring relationship factors and depressive symptoms.

Transcription factor YY1 can control AID-mediated mutagenesis in mice.

Science.gov (United States)

Zaprazna, Kristina; Basu, Arindam; Tom, Nikola; Jha, Vibha; Hodawadekar, Suchita; Radova, Lenka; Malcikova, Jitka; Tichy, Boris; Pospisilova, Sarka; Atchison, Michael L

2018-02-01

Activation-induced cytidine deminase (AID) is crucial for controlling the immunoglobulin (Ig) diversification processes of somatic hypermutation (SHM) and class switch recombination (CSR). AID initiates these processes by deamination of cytosine, ultimately resulting in mutations or double strand DNA breaks needed for SHM and CSR. Levels of AID control mutation rates, and off-target non-Ig gene mutations can contribute to lymphomagenesis. Therefore, factors that control AID levels in the nucleus can regulate SHM and CSR, and may contribute to disease. We previously showed that transcription factor YY1 can regulate the level of AID in the nucleus and Ig CSR. Therefore, we hypothesized that conditional knock-out of YY1 would lead to reduction in AID localization at the Ig locus, and reduced AID-mediated mutations. Using mice that overexpress AID (IgκAID yy1 f/f ) or that express normal AID levels (yy1 f/f ), we found that conditional knock-out of YY1 results in reduced AID nuclear levels, reduced localization of AID to the Sμ switch region, and reduced AID-mediated mutations. We find that the mechanism of YY1 control of AID nuclear accumulation is likely due to YY1-AID physical interaction which blocks AID ubiquitination. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mechanism and the origins of stereospecificity in copper-catalyzed ring expansion of vinyl oxiranes: a traceless dual transition-metal-mediated process.

Science.gov (United States)

Mustard, Thomas J L; Mack, Daniel J; Njardarson, Jon T; Cheong, Paul Ha-Yeon

2013-01-30

Density functional theory computations of the Cu-catalyzed ring expansion of vinyloxiranes is mediated by a traceless dual Cu(I)-catalyst mechanism. Overall, the reaction involves a monomeric Cu(I)-catalyst, but a single key step, the Cu migration, requires two Cu(I)-catalysts for the transformation. This dual-Cu step is found to be a true double Cu(I) transition state rather than a single Cu(I) transition state in the presence of an adventitious, spectator Cu(I). Both Cu(I) catalysts are involved in the bond forming and breaking process. The single Cu(I) transition state is not a stationary point on the potential energy surface. Interestingly, the reductive elimination is rate-determining for the major diastereomeric product, while the Cu(I) migration step is rate-determining for the minor. Thus, while the reaction requires dual Cu(I) activation to proceed, kinetically, the presence of the dual-Cu(I) step is untraceable. The diastereospecificity of this reaction is controlled by the Cu migration step. Suprafacial migration is favored over antarafacial migration due to the distorted Cu π-allyl in the latter.

The Mediator Complex MED15 Subunit Mediates Activation of Downstream Lipid-Related Genes by the WRINKLED1 Transcription Factor.

Science.gov (United States)

Kim, Mi Jung; Jang, In-Cheol; Chua, Nam-Hai

2016-07-01

The Mediator complex is known to be a master coordinator of transcription by RNA polymerase II, and this complex is recruited by transcription factors (TFs) to target promoters for gene activation or repression. The plant-specific TF WRINKLED1 (WRI1) activates glycolysis-related and fatty acid biosynthetic genes during embryogenesis. However, no Mediator subunit has yet been identified that mediates WRI1 transcriptional activity. Promoter-β-glucuronidase fusion experiments showed that MEDIATOR15 (MED15) is expressed in the same cells in the embryo as WRI1. We found that the Arabidopsis (Arabidopsis thaliana) MED15 subunit of the Mediator complex interacts directly with WRI1 in the nucleus. Overexpression of MED15 or WRI1 increased transcript levels of WRI1 target genes involved in glycolysis and fatty acid biosynthesis; these genes were down-regulated in wild-type or WRI1-overexpressing plants by silencing of MED15 However, overexpression of MED15 in the wri1 mutant also increased transcript levels of WRI1 target genes, suggesting that MED15 also may act with other TFs to activate downstream lipid-related genes. Chromatin immunoprecipitation assays confirmed the association of MED15 with six WRI1 target gene promoters. Additionally, silencing of MED15 resulted in reduced fatty acid content in seedlings and mature seeds, whereas MED15 overexpression increased fatty acid content in both developmental stages. Similar results were found in wri1 mutant and WRI1 overexpression lines. Together, our results indicate that the WRI1/MED15 complex transcriptionally regulates glycolysis-related and fatty acid biosynthetic genes during embryogenesis. © 2016 American Society of Plant Biologists. All Rights Reserved.

Analytic hierarchy process helps select site for limestone quarry expansion in Barbados.

Science.gov (United States)

Dey, Prasanta Kumar; Ramcharan, Eugene K

2008-09-01

Site selection is a key activity for quarry expansion to support cement production, and is governed by factors such as resource availability, logistics, costs, and socio-economic-environmental factors. Adequate consideration of all the factors facilitates both industrial productivity and sustainable economic growth. This study illustrates the site selection process that was undertaken for the expansion of limestone quarry operations to support cement production in Barbados. First, alternate sites with adequate resources to support a 25-year development horizon were identified. Second, technical and socio-economic-environmental factors were then identified. Third, a database was developed for each site with respect to each factor. Fourth, a hierarchical model in analytic hierarchy process (AHP) framework was then developed. Fifth, the relative ranking of the alternate sites was then derived through pair wise comparison in all the levels and through subsequent synthesizing of the results across the hierarchy through computer software (Expert Choice). The study reveals that an integrated framework using the AHP can help select a site for the quarry expansion project in Barbados.

Mediating and moderating influences of demographic factors in adult tobacco use

Directory of Open Access Journals (Sweden)

Lalfakzuali Chhakchhuak

2018-03-01

The study has given us baseline results of the mediators and moderators of demographic factors in tobacco use. For effective interventions targeting vulnerable groups like women, children and people from low education background, interventions should include training, cessation treatments and awareness assimilated through the church, Young Mizo Association, primary schools and health care centers. Focusing on these key areas will be very important in customizing and enhancing tobacco interventions among the present population.

Environmental factors influencing gene transfer agent (GTA mediated transduction in the subtropical ocean.

Directory of Open Access Journals (Sweden)

Lauren D McDaniel

Full Text Available Microbial genomic sequence analyses have indicated widespread horizontal gene transfer (HGT. However, an adequate mechanism accounting for the ubiquity of HGT has been lacking. Recently, high frequencies of interspecific gene transfer have been documented, catalyzed by Gene Transfer Agents (GTAs of marine α-Proteobacteria. It has been proposed that the presence of bacterial genes in highly purified viral metagenomes may be due to GTAs. However, factors influencing GTA-mediated gene transfer in the environment have not yet been determined. Several genomically sequenced strains containing complete GTA sequences similar to Rhodobacter capsulatus (RcGTA, type strain were screened to ascertain if they produced putative GTAs, and at what abundance. Five of nine marine strains screened to date spontaneously produced virus-like particles (VLP's in stationary phase. Three of these strains have demonstrated gene transfer activity, two of which were documented by this lab. These two strains Roseovarius nubinhibens ISM and Nitratireductor 44B9s, were utilized to produce GTAs designated RnGTA and NrGTA and gene transfer activity was verified in culture. Cell-free preparations of purified RnGTA and NrGTA particles from marked donor strains were incubated with natural microbial assemblages to determine the level of GTA-mediated gene transfer. In conjunction, several ambient environmental parameters were measured including lysogeny indicated by prophage induction. GTA production in culture systems indicated that approximately half of the strains produced GTA-like particles and maximal GTA counts ranged from 10-30% of host abundance. Modeling of GTA-mediated gene transfer frequencies in natural samples, along with other measured environmental variables, indicated a strong relationship between GTA mediated gene transfer and the combined factors of salinity, multiplicity of infection (MOI and ambient bacterial abundance. These results indicate that GTA-mediated

Fibroblast growth factor-mediated proliferation of central nervous system precursors depends on endogenous production of insulin-like growth factor I

International Nuclear Information System (INIS)

Drago, J.; Murphy, M.; Carroll, S.M.; Harvey, R.P.; Bartlett, P.F.

1991-01-01

Fibroblast growth factor stimulates proliferation and subsequent differentiation of precursor cells isolated from the neuroepithelium of embryonic day 10 mice in vitro. Here we show that fibroblast growth factor-induced proliferation is dependent on the presence of insulin-like growth factors (IGFs) and that IGF-I is endogenously produced by the neuroepithelial cells. Blocking of endogenous IGF-I activity with anti-IGF-I antibodies results in complete inhibition of fibroblast growth factor-mediated proliferation and in cell death. IGF-I alone acts as a survival agent. These observations correlate with the detection of transcripts for IGF-I and basic fibroblast growth factor in freshly isolated neuroepithelium and are consistent with an autocrine action of these factors in early brain development in vivo

Adsorbate-Induced Expansion of Silicalite-1 Crystals

Czech Academy of Sciences Publication Activity Database

Sorenson, S. G.; Smyth, J. R.; Kočiřík, Milan; Zikánová, Arlette; Noble, R. D.; Falconer, J. L.

2008-01-01

Roč. 47, č. 23 (2008), s. 9611-9616 ISSN 0888-5885 Institutional research plan: CEZ:AV0Z40400503 Keywords : X-ray diffraction * negative thermal expansion * zeolite membranes Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.895, year: 2008

Does adiposity mediate the relationship between physical activity and biological risk factors in youth?

DEFF Research Database (Denmark)

Tarp, J; Bugge, A; Andersen, L B

2018-01-01

BACKGROUND/OBJECTIVES: To model the association between accumulating 60 daily minutes of moderate-to-vigorous physical activity and a composite score of biological risk factors into a direct and an indirect effect, using abdominal obesity as the mediator. SUBJECTS/METHODS: Cross-sectional data from.......11, -0.02) to the indirect effect indicating that 22% of the total effect was mediated by central adiposity. Modelling 30 and 90 min of moderate-to-vigorous physical activity per day resulted in changes in the direct but not the indirect effect. CONCLUSIONS: One hour of daily moderate...... of insulin, glucose, triacylglycerol and inverse HDL-cholesterol. Abdominal obesity was assessed by the waist-circumference:height ratio. Two-stage regression analysis, allowing for exposure-mediator interaction, was used for the effect decomposition. RESULTS: Participants achieving 60 daily minutes...

Depression as a mediator between family factors and peer-bullying victimization in Latino adolescents.

Science.gov (United States)

Yabko, Brandon A; Hokoda, Audrey; Ulloa, Emilio C

2008-01-01

The purpose of this study was to assess the mediating role of depression in three different relationships: (a) sibling bullying and peer victimization, (b) mothers' power-assertive parenting and peer victimization, and (c) fathers' power-assertive parenting and peer victimization. Results from 242 Latino middle school adolescents from a large southwestern city bordering Mexico revealed that both boys' and girls' peer victimization were related to familial factors and depression. Regression analyses for boys revealed that depression mediated three relationships: (a) sibling bullying and peer victimization, (b) mothers' power-assertive parenting and peer victimization, and (c) fathers' power-assertive parenting and peer victimization. Depression also mediated the relationship between fathers' power-assertive parenting and girls' victimization by peers. The findings support the development of family-based interventions for peer victimization that include curriculum addressing depression.

Is intercultural mediation necessary? An approach from a communications perspective

Directory of Open Access Journals (Sweden)

Susana Ridao Rodrigo

2014-10-01

Full Text Available Institutionalized intercultural mediation is expanding as a result of the increase in the number of immigrants in our country. Institutionalized intercultural mediation, which started in the early Nineties in Spain, is understood to mean activities carried out by ONGs and by the social services of the host nation. In line with Giménez (1997: 127, we understand intercultural mediation as a modality within the broader field of mediation. Because of its recent expansion, there is not at present a unique methodology accepted by experts in this field. In this paper, our aims are focused on describing various mediation techniques and the possibility of their application within intercultural contexts

Childhood abuse and late-life depression: Mediating effects of psychosocial factors for early- and late-onset depression.

Science.gov (United States)

Wielaard, Ilse; Hoyer, Mathijs; Rhebergen, Didi; Stek, Max L; Comijs, Hannie C

2018-03-01

Childhood abuse makes people vulnerable to developing depression, even in late life. Psychosocial factors that are common in late life, such as loneliness or lack of a partner, may explain this association. Our aim was to investigate whether the association between childhood abuse and depression in older adults can be explained by psychosocial factors. Cross-sectional data were derived from the Netherlands Study of Depression in Older Persons (aged 60-93), including 132 without lifetime depression, 242 persons with an early-onset depression (Childhood abuse (yes/no) and a frequency-based childhood abuse index were included. Multinomial regression and multivariable mediation analyses were used to examine the association between childhood abuse and the onset of depression, and the influence of loneliness, social network, and partner status. Multinomial regression analyses showed a significant association between childhood abuse and the childhood abuse index with early- and late-onset depression. Multivariable mediation analyses showed that the association between childhood abuse and early-onset depression was partly mediated by social network size and loneliness. This was particularly present for emotional neglect and psychological abuse, but not for physical and sexual abuse. No psychosocial mediators were found for the association between childhood abuse and late-onset depression. A smaller social network and feelings of loneliness mediate the association between childhood abuse and early-onset depression in older adults. Our findings show the importance of detecting childhood abuse as well as the age at depression onset and mapping of relevant psychosocial factors in the treatment of late-life depression. Copyright © 2018 John Wiley & Sons, Ltd.

Do Sleep and Psychological Distress Mediate the Association Between Neighborhood Factors and Pain?

Science.gov (United States)

Brooks Holliday, Stephanie; Dubowitz, Tamara; Ghosh-Dastidar, Bonnie; Beckman, Robin; Buysse, Daniel; Hale, Lauren; Buman, Matthew; Troxel, Wendy

2018-05-14

Pain affects millions of American adults. However, individuals from socioeconomically disadvantaged groups experience higher rates of pain, and individuals from racial/ethnic minorities report greater pain severity and pain-related disability. Some studies find an association between neighborhood socioeconomic status and pain. The present study aimed to further understand the association between neighborhood disadvantage and pain, including the role of objective (e.g., crime rates) and subjective neighborhood characteristics (e.g., perceived safety, neighborhood satisfaction), and to examine sleep and psychological distress as potential mediators of these associations. The sample included 820 participants from two predominantly African American socioeconomically disadvantaged neighborhoods. Trained data collectors interviewed participants on a number of self-report measures, and objective neighborhood characteristics were obtained from city crime data and street segment audits. Subjective characteristics, specifically perceived infrastructure and perceived safety, were associated with pain. Based on bootstrapped regression models, sleep efficiency and psychological distress were tested as mediators of the association between these neighborhood factors and pain. Results of mediation testing indicated that psychological distress served as a significant mediator. Though sleep efficiency was not a mediator, it had a significant independent association with pain. Understanding the contribution of sleep problems and psychological distress to pain among at-risk individuals living in disadvantaged neighborhoods is important to identifying ways that individual- and neighborhood-level interventions may be leveraged to reduce pain-related disparities.

Nfatc1 Is a Functional Transcriptional Factor Mediating Nell-1-Induced Runx3 Upregulation in Chondrocytes

Directory of Open Access Journals (Sweden)

Chenshuang Li

2018-01-01

Full Text Available Neural EGFL like 1 (Nell-1 is essential for chondrogenic differentiation, maturation, and regeneration. Our previous studies have demonstrated that Nell-1’s pro-chondrogenic activities are predominantly reliant upon runt-related transcription factor 3 (Runx3-mediated Indian hedgehog (Ihh signaling. Here, we identify the nuclear factor of activated T-cells 1 (Nfatc1 as the key transcriptional factor mediating the Nell-1 → Runx3 signal transduction in chondrocytes. Using chromatin immunoprecipitation assay, we were able to determine that Nfatc1 binds to the −833–−810 region of the Runx3-promoter in response to Nell-1 treatment. By revealing the Nell-1 → Nfatc1 → Runx3 → Ihh cascade, we demonstrate the involvement of Nfatc1, a nuclear factor of activated T-cells, in chondrogenesis, while providing innovative insights into developing a novel therapeutic strategy for cartilage regeneration and other chondrogenesis-related conditions.

Extracellular-matrix-mediated osmotic pressure drives Vibrio cholerae biofilm expansion and cheater exclusion.

Science.gov (United States)

Yan, Jing; Nadell, Carey D; Stone, Howard A; Wingreen, Ned S; Bassler, Bonnie L

2017-08-23

Biofilms, surface-attached communities of bacteria encased in an extracellular matrix, are a major mode of bacterial life. How the material properties of the matrix contribute to biofilm growth and robustness is largely unexplored, in particular in response to environmental perturbations such as changes in osmotic pressure. Here, using Vibrio cholerae as our model organism, we show that during active cell growth, matrix production enables biofilm-dwelling bacterial cells to establish an osmotic pressure difference between the biofilm and the external environment. This pressure difference promotes biofilm expansion on nutritious surfaces by physically swelling the colony, which enhances nutrient uptake, and enables matrix-producing cells to outcompete non-matrix-producing cheaters via physical exclusion. Osmotic pressure together with crosslinking of the matrix also controls the growth of submerged biofilms and their susceptibility to invasion by planktonic cells. As the basic physicochemical principles of matrix crosslinking and osmotic swelling are universal, our findings may have implications for other biofilm-forming bacterial species.Most bacteria live in biofilms, surface-attached communities encased in an extracellular matrix. Here, Yan et al. show that matrix production in Vibrio cholerae increases the osmotic pressure within the biofilm, promoting biofilm expansion and physical exclusion of non-matrix producing cheaters.

Negative thermal expansion materials: technological key for control of thermal expansion

OpenAIRE

Koshi Takenaka

2012-01-01

Most materials expand upon heating. However, although rare, some materials contract upon heating. Such negative thermal expansion (NTE) materials have enormous industrial merit because they can control the thermal expansion of materials. Recent progress in materials research enables us to obtain materials exhibiting negative coefficients of linear thermal expansion over −30 ppm K−1. Such giant NTE is opening a new phase of control of thermal expansion in composites. Specifically examining pra...

Maternal Factors as Moderators or Mediators of PTSD Symptoms in Very Young Children: A Two-Year Prospective Study.

Science.gov (United States)

Scheeringa, Michael S; Myers, Leann; Putnam, Frank W; Zeanah, Charles H

2015-07-01

Research has suggested that parenting behaviors and other parental factors impact the long-term outcome of children's posttraumatic stress disorder (PTSD) symptoms. In a sample of 62 children between the ages of one and six who experienced life-threatening traumas, PTSD was measured prospectively two years apart. Seven maternal factors were measured in a multi-method, multi-informant design. Both moderation and mediation models, with different theoretical and mechanism implications, were tested. Moderation models were not significant. Mediation models were significant when the mediator variable was maternal symptoms of PTSD or depression (measured at Time 1), self-report of maternal escape/avoidance coping (measured at Time 2), or self-report emotional sensitivity (measured at Time 2). Greater maternal emotional sensitivity was associated with greater Time 2 PTSD symptoms among children. Observational measures of emotional sensitivity as the mediator were not supported. Correlation of parents' and children's symptoms is a robust finding, however caution is warranted in attributing children's PTSD symptoms to insensitive parenting.

Following Surgically Assisted Rapid Palatal Expansion, Do Tooth-Borne or Bone-Borne Appliances Provide More Skeletal Expansion and Dental Expansion?

Science.gov (United States)

Hamedi-Sangsari, Adrien; Chinipardaz, Zahra; Carrasco, Lee

2017-10-01

The aim of this study was to compare outcome measurements of skeletal and dental expansion with bone-borne (BB) versus tooth-borne (TB) appliances after surgically assisted rapid palatal expansion (SARPE). This study was performed to provide quantitative measurements that will help the oral surgeon and orthodontist in selecting the appliance with, on average, the greatest amount of skeletal expansion and the least amount of dental expansion. A computerized database search was performed using PubMed, EBSCO, Cochrane, Scopus, Web of Science, and Google Scholar on publications in reputable oral surgery and orthodontic journals. A systematic review and meta-analysis was completed with the predictor variable of expansion appliance (TB vs BB) and outcome measurement of expansion (in millimeters). Of 487 articles retrieved from the 6 databases, 5 articles were included, 4 with cone-beam computed tomographic (CBCT) data and 1 with non-CBCT 3-dimensional cast data. There was a significant difference in skeletal expansion (standardized mean difference [SMD], 0.92; 95% confidence interval [CI], 0.54-1.30; P appliances. However, there was no significant difference in dental expansion (SMD, 0.05; 95% CI, -0.24 to 0.34; P = .03). According to the literature, to achieve more effective skeletal expansion and minimize dental expansion after SARPE, a BB appliance should be favored. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Preliminary thermal expansion screening data for tuffs

International Nuclear Information System (INIS)

Lappin, A.R.

1980-03-01

A major variable in evaluating the potential of silicic tuffs for use in geologic disposal of heat-producing nuclear wastes is thermal expansion. Results of ambient-pressure linear expansion measurements on a group of tuffs that vary treatly in porosity and mineralogy are presente here. Thermal expansion of devitrified welded tuffs is generally linear with increasing temperature and independent of both porosity and heating rate. Mineralogic factors affecting behavior of these tuffs are limited to the presence or absence of cristobalite and altered biotite. The presence of cristobalite results in markedly nonlinear expansion above 200 0 C. If biotite in biotite-hearing rocks alters even slightly to expandable clays, the behavior of these tuffs near the boiling point of water can be dominated by contraction of the expandable phase. Expansion of both high- and low-porosity tuffs containing hydrated silicic glass and/or expandable clays is complex. The behavior of these rocks appears to be completely dominated by dehydration of hydrous phases and, hence, should be critically dependent on fluid pressure. Valid extrapolation of the ambient-pressure results presented here to depths of interest for construction of a nuclear-waste repository will depend on a good understanding of the interaction of dehydration rates and fluid pressures, and of the effects of both micro- and macrofractures on the response of tuff masss

Ultraviolet Radiation and the Slug Transcription Factor Induce Proinflammatory and Immunomodulatory Mediator Expression in Melanocytes

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Stephanie H. Shirley

2012-01-01

Full Text Available Despite extensive investigation, the precise contribution of the ultraviolet radiation (UVR component of sunlight to melanoma etiology remains unclear. UVR induces keratinocytes to secrete proinflammatory and immunomodulatory mediators that promote inflammation and skin tumor development; expression of the slug transcription factor in keratinocytes is required for maximal production of these mediators. In the present studies we examined the possibility that UVR-exposed melanocytes also produce proinflammatory mediators and that Slug is important in this process. Microarray studies revealed that both UVR exposure and Slug overexpression altered transcription of a variety of proinflammatory mediators by normal human melanocytes; some of these mediators are also known to stimulate melanocyte growth and migration. There was little overlap in the spectra of cytokines produced by the two stimuli. However IL-20 was similarly induced by both stimuli and the NFκB pathway appeared to be important in both circumstances. Further exploration of UVR-induced and Slug-dependent pathways of cytokine induction in melanocytes may reveal novel targets for melanoma therapy.

Emotional well-being in children with epilepsy: Family factors as mediators and moderators.

Science.gov (United States)

Goodwin, Shane W; Wilk, Piotr; Karen Campbell, M; Speechley, Kathy N

2017-11-01

Our objective was to examine the relationships of factors associated with children's emotional well-being 2 years after diagnosis, and to examine if these relationships are mediated or moderated by family factors. Data came from a multicenter prospective cohort study of children with newly diagnosed epilepsy from across Canada (Health-Related Quality of Life in Children with Epilepsy Study; HERQULES, n = 373). Emotional well-being was assessed using the Quality of Life in Childhood Epilepsy Questionnaire (QOLCE-55). The relationships between clinical factors, family factors, and emotional well-being were assessed using multiple regression analyses. Family functioning, family stress, and repertoire of resources that the families had to adapt to stressful events were significantly associated with poor emotional well-being 2 years after diagnosis (p < 0.05) in the multivariable analysis. The effect of parental depressive symptoms was partially mediated by family functioning and family stress (p < 0.01 and p = 0.02, respectively). Family resources acted as a moderator in the relationship between severity of epilepsy and emotional well-being (p < 0.05). Based on our findings, efforts to strengthen the family environment may warrant attention. We suggest that clinicians take a family centered care approach by including families in treatment planning. Family centered care has been shown to improve family well-being and coping and in turn may reduce the impact of clinical factors on emotional well-being to improve long-term health-related quality of life. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

Medicaid expansion and access to care among cancer survivors: a baseline overview.

Science.gov (United States)

Tarazi, Wafa W; Bradley, Cathy J; Harless, David W; Bear, Harry D; Sabik, Lindsay M

2016-06-01

Medicaid expansion under the Affordable Care Act facilitates access to care among vulnerable populations, but 21 states have not yet expanded the program. Medicaid expansions may provide increased access to care for cancer survivors, a growing population with chronic conditions. We compare access to health care services among cancer survivors living in non-expansion states to those living in expansion states, prior to Medicaid expansion under the Affordable Care Act. We use the 2012 and 2013 Behavioral Risk Factor Surveillance System to estimate multiple logistic regression models to compare inability to see a doctor because of cost, having a personal doctor, and receiving an annual checkup in the past year between cancer survivors who lived in non-expansion states and survivors who lived in expansion states. Cancer survivors in non-expansion states had statistically significantly lower odds of having a personal doctor (adjusted odds ratio [AOR] 0.76, 95 % confidence interval [CI] 0.63-0.92, p Medicaid could potentially leave many cancer survivors with limited access to routine care. Existing disparities in access to care are likely to widen between cancer survivors in Medicaid non-expansion and expansion states.

Streamtube expansion effects on the Darrieus wind turbine

Science.gov (United States)

Paraschivoiu, I.; Fraunie, P.; Beguier, C.

1985-04-01

The purpose of the work described in this paper was to determine the aerodynamic loads and performance of a Darrieus wind turbine by including the expansion effects of the streamtubes through the rotor. The double-multiple streamtube model with variable interference factors was used to estimate the induced velocities with a modified CARDAAV computer code. Comparison with measured data and predictions shows that the stream-tube expansion effects are relatively significant at high tip-speed ratios, allowing a more realistic modeling of the upwind/downwind flowfield asymmetries inherent in the Darrieus rotor.

Hypoxia-inducible factors regulate pluripotency factor expression by ZNF217- and ALKBH5-mediated modulation of RNA methylation in breast cancer cells.

Science.gov (United States)

Zhang, Chuanzhao; Zhi, Wanqing Iris; Lu, Haiquan; Samanta, Debangshu; Chen, Ivan; Gabrielson, Edward; Semenza, Gregg L

2016-10-04

Exposure of breast cancer cells to hypoxia increases the percentage of breast cancer stem cells (BCSCs), which are required for tumor initiation and metastasis, and this response is dependent on the activity of hypoxia-inducible factors (HIFs). We previously reported that exposure of breast cancer cells to hypoxia induces the ALKBH5-mediated demethylation of N6-methyladenosine (m6A) in NANOG mRNA leading to increased expression of NANOG, which is a pluripotency factor that promotes BCSC specification. Here we report that exposure of breast cancer cells to hypoxia also induces ZNF217-dependent inhibition of m6A methylation of mRNAs encoding NANOG and KLF4, which is another pluripotency factor that mediates BCSC specification. Although hypoxia induced the BCSC phenotype in all breast-cancer cell lines analyzed, it did so through variable induction of pluripotency factors and ALKBH5 or ZNF217. However, in every breast cancer line, the hypoxic induction of pluripotency factor and ALKBH5 or ZNF217 expression was HIF-dependent. Immunohistochemistry revealed that expression of HIF-1α and ALKBH5 was concordant in all human breast cancer biopsies analyzed. ALKBH5 knockdown in MDA-MB-231 breast cancer cells significantly decreased metastasis from breast to lungs in immunodeficient mice. Thus, HIFs stimulate pluripotency factor expression and BCSC specification by negative regulation of RNA methylation.

Upregulation of vascular endothelial growth factor receptor-1 contributes to sevoflurane preconditioning–mediated cardioprotection

Directory of Open Access Journals (Sweden)

Qian B

2018-04-01

Full Text Available Bin Qian,1 Yang Yang,2 Yusheng Yao,3 Yanling Liao,3 Ying Lin3 1Department of Anesthesiology, People’s Hospital Affiliated to Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, China; 2Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China; 3Department of Anesthesiology, The Shengli Clinical Medical College, Fujian Medical University, Fuzhou, Fujian, China Purpose: Sevoflurane preconditioning (SPC can provide myocardial protective effects similar to ischemic preconditioning. However, the exact mechanism of SPC remains unclear. Previous studies indicate that vascular endothelial growth factor receptor 1 (VEGFR-1 is involved in ischemic preconditioning-mediated cardioprotection. This study was designed to determine the significance of VEGFR-1 signaling in SPC-mediated cardioprotection.Materials and methods: Myocardial ischemia–reperfusion (I/R rat model was established using the Langendorff isolated heart perfusion apparatus. Additionally, after 15 min of baseline equilibration, the isolated hearts were pretreated with 2.5% sevoflurane, 2.5% sevoflurane+MF1 10 µmol/L, or 2.5% sevoflurane+placental growth factor 10 µmol/L, and then subjected to 30 min of global ischemia and 120 min of reperfusion. The changes in hemodynamic parameters, myocardial infarct size, and the levels of creatine kinase-MB, lactate dehydrogenase, cardiac troponin-I, tumor necrosis factor-α, and interleukin 6 in the myocardium were evaluated.Results: Compared to the I/R group, pretreatment with 2.5% sevoflurane significantly improved the cardiac function, limited myocardial infarct size, reduced cardiac enzyme release, upregulated VEGFR-1 expression, and decreased inflammation. In addition, the selective VEGFR-1 agonist, placental growth factor, did not enhance the cardioprotection and anti-inflammation effects of sevoflurane, while the specific VEGFR-1 inhibitor, MF1, completely reversed these effects

MEDIATOR18 and MEDIATOR20 confer susceptibility to Fusarium oxysporum in Arabidopsis thaliana

OpenAIRE

Fallath, Thorya; Kidd, Brendan N.; Stiller, Jiri; Davoine, Celine; Bj?rklund, Stefan; Manners, John M.; Kazan, Kemal; Schenk, Peer M.

2017-01-01

The conserved protein complex known as Mediator conveys transcriptional signals by acting as an intermediary between transcription factors and RNA polymerase II. As a result, Mediator subunits play multiple roles in regulating developmental as well as abiotic and biotic stress pathways. In this report we identify the head domain subunits MEDIATOR18 and MEDIATOR20 as important susceptibility factors for Fusarium oxysporum infection in Arabidopsis thaliana. Mutants of MED18 and MED20 display do...

Biomass equations and biomass expansion factors (BEFs) for pine (pinus spp.), spruce (picea spp.) and broadleaved dominated stands in Norway

OpenAIRE

Viken, Knut Ole

2012-01-01

Abstract The objectives of this study were (1) to develop models for estimation of stand-level tree biomass for spruce (picea spp.)- pine (pinus spp.)- and broadleaved-dominated forest in Norway and, (2) develop biomass expansion factors (BEFs; ratio of stem volume to biomass) which convert stem volume to whole tree biomass for Norwegian forest conditions. A dataset from a 5 year period (2006 – 2010) from the Norwegian National Forest Inventory (NFI) were used to develop the...

Gabor's signal expansion on a quincunx lattice and the modified Zak transform

NARCIS (Netherlands)

Leest, van A.J.; Bastiaans, M.J.

1999-01-01

Gabor's expansion of a signal on a quincunx lattice with oversampling by a rational factor is presented for continuous-time signals. It is shown how a modified Zak transform instead of the ordinary Zak transform can be helpful in determining Gabor's signal expansion coefficients and how it can be

Simulative research on the expansion of cathode plasma in high-current electron beam diode

International Nuclear Information System (INIS)

Xu Qifu; Liu Lie

2012-01-01

The expansion of cathode plasma has long been recognized as a limiting factor in the impedance lifetime of high-current electron beam diode. Realistic modeling of such plasma is of great necessity in order to discuss the dynamics of cathode plasma. Using the method of particle-in-cell, the expansion of cathode plasma is simulated in this paper by a scaled-down diode model. It is found that the formation of cathode plasma increases the current density in the diode. This consequently leads to the decrease of the potential at plasma front. Once the current density has been increased to a certain value, the potential at plasma front would then be equal to or lower than the plasma potential. Then the ions would move towards the anode, and the expansion of cathode plasma is thereby formed. Different factors affecting the plasma expansion velocity are discussed in this paper. It is shown that the decrease of proton genatation rate has the benefit of reducing the plasma expansion velocity.

Expansion And International Expansion Of Small-To Medium Sized Firms: The Role Of Finance

OpenAIRE

Jan Smolarski; Can Kut; Neil Wilner

2011-01-01

Small- to medium-sized firms are expected to show international growth at an early stage. Several factors may affect the outcome of initial efforts to expand and internationalize. Our research examines how equity based venture funding affects SME expansion and internationalization. We divide venture capital financing into two categories: incremental financing where firms receive their venture capital funding in portions and lump-sum venture funding where firms receive their funding in one lum...

Factors influencing electric utility expansion. Volume II

Energy Technology Data Exchange (ETDEWEB)

Masud, E. [ed.

1977-01-01

This report, Vol. 2, submitted by the General Electric Co., identifies factors that should be considered in planning interconnected systems and discusses how these factors relate to one another. The objective is to identify all the factors and classify them by their use and importance in arriving at a decision. Chapter 2 discusses the utility system and its system behavior characteristics, emphasizing behavior that affects the planning of the bulk-power generation and transmission system. Chapter 3 introduces interconnection planning by discussing the new system characteristics brought to operation and planning. Forty-two factors associated with cost, reliability, constraints, and coordination are related to each other by factor trees. Factor trees display the relationship of one factor such as reliability to more-detailed factors which in turn are further related to individual characteristics of facilities. These factor trees provide a structure to the presentation. A questionnaire including the 42 factors was completed by 52 system planners from utility companies and government authorities. The results of these questionnaires are tabulated and presented with pertinent discussion of each factor. Chapter 4 deals with generation planning, recognizing the existence of interconnections. Chapter 5 addresses transmission planning, questions related to reliability and cost measures and constraints, and factors related to both analytical techniques and planning procedures. The chapter ends with a discussion of combined generation-transmission planning. (MCW)

A Model for the Expansion of the Universe

Directory of Open Access Journals (Sweden)

Silva N. P.

2014-04-01

Full Text Available One introduces an ansatz for the expansion factor a ( t = e ( H ( t t or our Universe in the spirit of the FLRW model; is a constant to be determined. Considering that the ingredients acting on the Universe expansion ( t > 4 10 12 s 1 : 3 10 are mainly matter (baryons plus dark matter and dark energy, one uses the current mea- sured values of Hubble constant H 0 , the Universe current age T 0 , matter density param- eter Ω m ( T 0 and dark energy parameter Ω ( T 0 together with the Friedmann equations to find = 0 : 5804 and that our Universe may have had a negative expansion accelera- tion up to the age T ⋆ = 3 : 214 G y r ( matter era and positive after that ( dark energy era , leading to an eternal expansion. An interaction between matter and dark energy is found to exist. The deceleration q ( t has been found to be q ( T ⋆ = 0 and q ( T 0 = -0.570.

The study of the volume expansion of aluminum during porous oxide formation at galvanostatic regime

Energy Technology Data Exchange (ETDEWEB)

Vrublevsky, I.; Parkoun, V.; Sokol, V.; Schreckenbach, J.; Marx, G

2004-01-30

The volume expansion factor of porous alumina, formed by through anodizing of an Al foil of thickness 11.5 {mu}m in the range of current densities of 4-35 mA cm{sup -2} in oxalic and sulfuric acid at 18-24 deg. C has been studied. The microstructure of anodizing samples has been observed using scanning electron microscopy. The thickness of obtained porous alumina films was measured by a mechanical profilometer with a computer signal-processing. The volume expansion factor of porous alumina varied from 1.35 to 1.65. Linear dependences were obtained for the volume expansion factor of porous alumina versus the anodizing voltage and the ionic current-density logarithm versus the inverse volume expansion factor. Unlike oxide formation in sulfuric acid, these dependences have two subsequential rectilinear regions in oxalic acid. This peculiarity of the dependences in oxalic acid was explained by formation of a region of the immobile negative space charge in the barrier Al oxide layer and its influence on the ionic transport.

Antiretroviral treatment adherence as a mediating factor between psychosocial variables and HIV viral load.

Science.gov (United States)

Attonito, Jennifer; Dévieux, Jessy G; Lerner, Brenda D G; Hospital, Michelle M; Rosenberg, Rhonda

2014-01-01

Psychosocial factors may directly impact HIV health measures such as viral load (VL) whether or not patients are taking antiretroviral treatment (ART) consistently. Structural equation modeling plus Baron and Kenny's (1986) four-step approach were used to test a mediated model predicting VL among 246 HIV-infected adults who were on ART. Exogenous variables were social support, barriers to adherence, and stress. Moderators were alcohol use, marijuana use, and neurocognitive impairment. A small positive association between marijuana use and ART adherence approached significance. Only barriers to adherence predicted a decrease in adherence rates and an increase in VL. No other factors were significantly associated with either VL or adherence, and no interaction effects between exogenous variables and moderators were identified. The association between barriers to adherence and VL was partially mediated by ART adherence. Findings provide modest support for a direct link between psychosocial variables and a virologic response to ART. Copyright © 2014 Association of Nurses in AIDS Care. Published by Elsevier Inc. All rights reserved.

Short-term exposure of umbilical cord blood CD34+ cells to granulocyte-macrophage colony-stimulating factor early in culture improves ex vivo expansion of neutrophils.

Science.gov (United States)

Marturana, Flavia; Timmins, Nicholas E; Nielsen, Lars K

2011-03-01

Despite the availability of modern antibiotics/antimycotics and cytokine support, neutropenic infection accounts for the majority of chemotherapy-associated deaths. While transfusion support with donor neutrophils is possible, cost and complicated logistics make such an option unrealistic on a routine basis. A manufactured neutrophil product could enable routine prophylactic administration of neutrophils, preventing the onset of neutropenia and substantially reducing the risk of infection. We examined the use of pre-culture strategies and various cytokine/modulator combinations to improve neutrophil expansion from umbilical cord blood (UCB) hematopoietic stem and progenitor cells (HPC). Enriched UCB HPC were cultured using either two-phase pre-culture strategies or a single phase using various cytokine/modulator combinations. Outcome was assessed with respect to numerical expansion, cell morphology, granulation and respiratory burst activity. Pre-culture in the absence of strong differentiation signals (e.g. granulocyte colony-stimulating factor; G-CSF) failed to provide any improvement to final neutrophil yields. Similarly, removal of differentiating cells during pre-culture failed to improve neutrophil yields to an appreciable extent. Of the cytokine/modulator combinations, the addition of granulocyte-macrophage (GM)-colony-stimulating factor (CSF) alone gave the greatest increase. In order to avoid production of monocytes, it was necessary to remove GM-CSF on day 5. Using this strategy, neutrophil expansion improved 2.7-fold. Although all cytokines and culture strategies employed have been reported previously to enhance HPC expansion, we found that the addition of GM-CSF alone was sufficient to improve total cell yields maximally. The need to remove GM-CSF on day 5 to avoid monocyte differentiation highlights the context and time-dependent complexity of exogenous signaling in hematopoietic cell differentiation and growth.

Depressive and anxiety disorders and short leukocyte telomere length: mediating effects of metabolic stress and lifestyle factors.

Science.gov (United States)

Révész, D; Verhoeven, J E; Milaneschi, Y; Penninx, B W J H

2016-08-01

Depressive and anxiety disorders are associated with shorter leukocyte telomere length (LTL), an indicator of cellular aging. It is, however, unknown which pathways underlie this association. This study examined the extent to which lifestyle factors and physiological changes such as inflammatory or metabolic alterations mediate the relationship. We applied mediation analysis techniques to data from 2750 participants of the Netherlands Study of Depression and Anxiety. LTL was assessed using quantitative polymerase chain reaction. Independent variables were current depressive (30-item Inventory of Depressive Symptoms - Self Report) and anxiety (21-item Beck's Anxiety Inventory) symptoms and presence of a depressive or anxiety disorder diagnosis based on DSM-IV; mediator variables included physiological stress systems, metabolic syndrome components and lifestyle factors. Short LTL was associated with higher symptom severity (B = -2.4, p = 0.002) and current psychiatric diagnosis (B = -63.3, p = 0.024). C-reactive protein, interleukin-6, waist circumference, triglycerides, high-density lipoprotein cholesterol and cigarette smoking were significant mediators in the relationship between psychopathology and LTL. When all significant mediators were included in one model, the effect sizes of the relationships between LTL and symptom severity and current diagnosis were reduced by 36.7 and 32.7%, respectively, and the remaining direct effects were no longer significant. Pro-inflammatory cytokines, metabolic alterations and cigarette smoking are important mediators of the association between depressive and anxiety disorders and LTL. This calls for future research on intervention programs that take into account lifestyle changes in mental health care settings.

Negative thermal expansion materials

International Nuclear Information System (INIS)

Evans, J.S.O.

1997-01-01

The recent discovery of negative thermal expansion over an unprecedented temperature range in ZrW 2 O 8 (which contracts continuously on warming from below 2 K to above 1000 K) has stimulated considerable interest in this unusual phenomenon. Negative and low thermal expansion materials have a number of important potential uses in ceramic, optical and electronic applications. We have now found negative thermal expansion in a large new family of materials with the general formula A 2 (MO 4 ) 3 . Chemical substitution dramatically influences the thermal expansion properties of these materials allowing the production of ceramics with negative, positive or zero coefficients of thermal expansion, with the potential to control other important materials properties such as refractive index and dielectric constant. The mechanism of negative thermal expansion and the phase transitions exhibited by this important new class of low-expansion materials will be discussed. (orig.)

Transcription factor CREB is involved in CaSR-mediated cytoskeleton gene expression.

Science.gov (United States)

Huang, Shuaishuai; Ren, Yu; Wang, Ping; Li, Yanyuan; Wang, Xue; Zhuang, Haihui; Fang, Rong; Wang, Yuduo; Liu, Ningsheng; Hehir, Michael; Zhou, Jeff X

2015-03-01

Our previous studies illustrated that a steady increase of intracellular calcium concentration ([Ca2+]i) was important for maintaining microtubules (MTs) rearrangement in apoptotic cells. However, little is known about the effect of calcium sensing receptor (CaSR)-mediated increase in [Ca2+]i on cytoskeleton gene expression. We examined the impact of taxol or CaSR agonist/antagonist on the regulation of [Ca2+]i concentration, cytoskeleton arrangement, phosphorylated CREB and cytoskeleton gene expressions in HeLa cells with dominant negative plasmid of CREB (PM). This study demonstrated that Gdcl3 (a specific CaSR agonist) evoked a rapid increase of [Ca2+]i, formed a rigid bundle of MTs which surrounded the nucleus and decreased the cytoskeleton gene expressions in HeLa cells. These effects were rescued by addition of NPS2390 (a specific CaSR antagonist). Moreover, CaSR activity affected cytoskeleton gene expression through transcription factor CREB. Histoscores of pCREB immunoreactivity in tissues of cervical adenocarcinoma, renal clear cell carcinoma, and diffuse large B-cell lymphoma were markedly increased compared with non malignant tissue. These data demonstrate, for the first time, that CaSR-mediated increase in [Ca2+]i probably modulate cytoskeleton organization and gene expression via transcription factor. © 2014 Wiley Periodicals, Inc.

Negative thermal expansion materials: technological key for control of thermal expansion.

Science.gov (United States)

Takenaka, Koshi

2012-02-01

Most materials expand upon heating. However, although rare, some materials contract upon heating. Such negative thermal expansion (NTE) materials have enormous industrial merit because they can control the thermal expansion of materials. Recent progress in materials research enables us to obtain materials exhibiting negative coefficients of linear thermal expansion over -30 ppm K -1 . Such giant NTE is opening a new phase of control of thermal expansion in composites. Specifically examining practical aspects, this review briefly summarizes materials and mechanisms of NTE as well as composites containing NTE materials, based mainly on activities of the last decade.

Negative thermal expansion materials: technological key for control of thermal expansion

Directory of Open Access Journals (Sweden)

Koshi Takenaka

2012-01-01

Full Text Available Most materials expand upon heating. However, although rare, some materials contract upon heating. Such negative thermal expansion (NTE materials have enormous industrial merit because they can control the thermal expansion of materials. Recent progress in materials research enables us to obtain materials exhibiting negative coefficients of linear thermal expansion over −30 ppm K−1. Such giant NTE is opening a new phase of control of thermal expansion in composites. Specifically examining practical aspects, this review briefly summarizes materials and mechanisms of NTE as well as composites containing NTE materials, based mainly on activities of the last decade.

Negative thermal expansion materials: technological key for control of thermal expansion

International Nuclear Information System (INIS)

Takenaka, Koshi

2012-01-01

Most materials expand upon heating. However, although rare, some materials contract upon heating. Such negative thermal expansion (NTE) materials have enormous industrial merit because they can control the thermal expansion of materials. Recent progress in materials research enables us to obtain materials exhibiting negative coefficients of linear thermal expansion over −30 ppm K −1 . Such giant NTE is opening a new phase of control of thermal expansion in composites. Specifically examining practical aspects, this review briefly summarizes materials and mechanisms of NTE as well as composites containing NTE materials, based mainly on activities of the last decade. (topical review)

On the stress-free lattice expansion of porous cordierite

International Nuclear Information System (INIS)

Bruno, Giovanni; Efremov, Alexander M.; Clausen, Bjorn; Balagurov, Anatoly M.; Simkin, Valeriy N.; Wheaton, Bryan R.; Webb, James E.; Brown, Donald W.

2010-01-01

An extensive investigation of the lattice expansion (up to 1200 deg. C) of porous synthetic cordierite (obtained by firing a mixture of talc, clay, alumina and silica) was carried out using time-of-flight neutron diffraction at LANSCE, Los Alamos, NM, USA and FNLP, Dubna, Russia. An extruded rod and several powders, with different particle size (dispersity), were studied, with the aim of monitoring the variation of the (lattice) micro-strain as a function of temperature and its influence on the microscopic and macroscopic thermal expansion. Results show a different expansion of the a- and b-axes of the orthorhombic cell (in the rod above 800 deg. C). While the finest powder seems to contract more along the c-axis, thus hinting at the presence of smaller stress, the integral peak width increases as a function of temperature in the intermediate range (300-700 deg. C). This could be explained by the integrity factor modeling in terms of micro-cracking. In polycrystalline cordierite, the model implies tension along the a- and b-axes (positive thermal expansion) accompanied by compression along the c-axis (negative thermal expansion) and a stress release upon cooling, via a thermal micro-cracking mechanism. The calculations of the cordierite macroscopic thermal expansion having as input crystal axial expansions assumed to be stress-free allowed us to conclude that even a fine powder (5 μm particle size) cannot be considered completely stress-free. This conclusion is supported by microstructural observations.

Mediator MED23 Links Pigmentation and DNA Repair through the Transcription Factor MITF.

Science.gov (United States)

Xia, Min; Chen, Kun; Yao, Xiao; Xu, Yichi; Yao, Jiaying; Yan, Jun; Shao, Zhen; Wang, Gang

2017-08-22

DNA repair is related to many physiological and pathological processes, including pigmentation. Little is known about the role of the transcriptional cofactor Mediator complex in DNA repair and pigmentation. Here, we demonstrate that Mediator MED23 plays an important role in coupling UV-induced DNA repair to pigmentation. The loss of Med23 specifically impairs the pigmentation process in melanocyte-lineage cells and in zebrafish. Med23 deficiency leads to enhanced nucleotide excision repair (NER) and less DNA damage following UV radiation because of the enhanced expression and recruitment of NER factors to chromatin for genomic stability. Integrative analyses of melanoma cells reveal that MED23 controls the expression of a melanocyte master regulator, Mitf, by modulating its distal enhancer activity, leading to opposing effects on pigmentation and DNA repair. Collectively, the Mediator MED23/MITF axis connects DNA repair to pigmentation, thus providing molecular insights into the DNA damage response and skin-related diseases. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Diversity, expansion, and evolutionary novelty of plant DNA-binding transcription factor families.

Science.gov (United States)

Lehti-Shiu, Melissa D; Panchy, Nicholas; Wang, Peipei; Uygun, Sahra; Shiu, Shin-Han

2017-01-01

Plant transcription factors (TFs) that interact with specific sequences via DNA-binding domains are crucial for regulating transcriptional initiation and are fundamental to plant development and environmental response. In addition, expansion of TF families has allowed functional divergence of duplicate copies, which has contributed to novel, and in some cases adaptive, traits in plants. Thus, TFs are central to the generation of the diverse plant species that we see today. Major plant agronomic traits, including those relevant to domestication, have also frequently arisen through changes in TF coding sequence or expression patterns. Here our goal is to provide an overview of plant TF evolution by first comparing the diversity of DNA-binding domains and the sizes of these domain families in plants and other eukaryotes. Because TFs are among the most highly expanded gene families in plants, the birth and death process of TFs as well as the mechanisms contributing to their retention are discussed. We also provide recent examples of how TFs have contributed to novel traits that are important in plant evolution and in agriculture.This article is part of a Special Issue entitled: Plant Gene Regulatory Mechanisms and Networks, edited by Dr. Erich Grotewold and Dr. Nathan Springer. Copyright © 2016 Elsevier B.V. All rights reserved.

Cropland expansion in Brazil, 2000 to 2014

Science.gov (United States)

Zalles, V.; Hansen, M.; Potapov, P.; Stehman, S. V.; Tyukavina, A.; Pickens, A. H.; Okpa, C.; Aguilar, R.; John, N.; Chavez, S.

2017-12-01

Brazil has become a global leader in the production of commodity row crops such as soybean, sugarcane, cotton, and corn. Here, we employ 30m spatial resolution Landsat data to estimate cropland extent in the year 2000 and its subsequent expansion through 2014. A probability-based sample of reference data allows us to report unbiased estimates of national, biome, and state-scale area of crop expansion with associated uncertainties. We find an increase in Brazilian cropland extent from 26.0 Mha in 2000 to 46.1 Mha in 2014. The cropland frontier states of Maranhao, Tocantins, Piaui, Bahia (MATOPIBA), Mato Grosso, Mato Grosso do Sul, and Para all more than doubled in cropland extent. The states of Goias, Minas Gerais and Sao Paulo experienced >50% increases. The vast majority of expansion, 79%, occurred on repurposed pasture lands, and 20% from the conversion of natural vegetation. Area of converted Cerrado savannas was nearly 2.5 times that of Amazon forests, and accounted for over half of new cropland in MATOPIBA. Spatio-temporal dynamics of cropland expansion are reflected in market conditions, land use policies, and other factors. Continued extensification of cropland is a viable option across Brazil with attendant benefits for and challenges to development.

Thermal expansion of coking coals

Energy Technology Data Exchange (ETDEWEB)

Orlik, M.; Klimek, J. (Vyzkumny a Zkusebni Ustav Nova Hut, Ostrava (Czechoslovakia))

1992-12-01

Analyzes expansion of coal mixtures in coke ovens during coking. Methods for measuring coal expansion on both a laboratory and pilot plant scale are comparatively evaluated. The method, developed, tested and patented in Poland by the Institute for Chemical Coal Processing in Zabrze (Polish standard PN-73/G-04522), is discussed. A laboratory device developed by the Institute for measuring coal expansion is characterized. Expansion of black coal from 10 underground mines in the Ostrava-Karvina coal district and from 9 coal mines in the Upper Silesia basin in Poland is comparatively evaluated. Investigations show that coal expansion reaches a maximum for coal types with a volatile matter ranging from 20 to 25%. With increasing volatile matter in coal, its expansion decreases. Coal expansion increases with increasing swelling index. Coal expansion corresponds with coal dilatation. With increasing coal density its expansion increases. Coal mixtures should be selected in such a way that their expansion does not cause a pressure exceeding 40 MPa. 11 refs.

Mediatization: a concept, multiple voices

Directory of Open Access Journals (Sweden)

Pedro Gilberto GOMES

2016-12-01

Full Text Available Mediatization has become increasingly a key concept, fundamental, essential to describe the present and the history of media and communicative change taking place. Thus, it became part of a whole, one can not see them as a separate sphere. In this perspective, the media coverage is used as a concept to describe the process of expansion of the different technical means and consider the interrelationships between the communicative change, means and sociocultural change. However, although many researchers use the concept of mediatization, each gives you the meaning that best suits your needs. Thus, the concept of media coverage is treated with multiple voices. This paper discusses this problem and present a preliminary pre-position on the matter.

Analytic continuation and perturbative expansions in QCD

Czech Academy of Sciences Publication Activity Database

Caprini, I.; Fischer, Jan

2002-01-01

Roč. 24, - (2002), s. 127-135 ISSN 1434-6044 R&D Projects: GA MPO RP-4210/69 Institutional research plan: CEZ:AV0Z1010920 Keywords : perturbative expansion * quantum chromodynamics * infrared ambiguity * essential singularities Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 6.162, year: 2002

Ultraviolet Radiation and the Slug Transcription Factor Induce Pro inflammatory and Immunomodulatory Mediator Expression in Melanocytes

International Nuclear Information System (INIS)

Shirley, S. H.; Kusewitt, D. F.; Grimm, E. A.

2012-01-01

Despite extensive investigation, the precise contribution of the ultraviolet radiation (UVR) component of sunlight to melanoma etiology remains unclear. UVR induces keratinocytes to secrete pro inflammatory and immunomodulatory mediators that promote inflammation and skin tumor development; expression of the slug transcription factor in keratinocytes is required for maximal production of these mediators. In the present studies we examined the possibility that UVR-exposed melanocytes also produce pro inflammatory mediators and that Slug is important in this process. Micro array studies revealed that both UVR exposure and Slug overexpression altered transcription of a variety of pro inflammatory mediators by normal human melanocytes; some of these mediators are also known to stimulate melanocyte growth and migration. There was little overlap in the spectra of cytokines produced by the two stimuli. However IL-20 was similarly induced by both stimuli and the NFκB pathway appeared to be important in both circumstances. Further exploration of UVR-induced and Slug-dependent pathways of cytokine induction in melanocytes may reveal novel targets for melanoma therapy.

Virial Expansion Bounds

Science.gov (United States)

Tate, Stephen James

2013-10-01

In the 1960s, the technique of using cluster expansion bounds in order to achieve bounds on the virial expansion was developed by Lebowitz and Penrose (J. Math. Phys. 5:841, 1964) and Ruelle (Statistical Mechanics: Rigorous Results. Benjamin, Elmsford, 1969). This technique is generalised to more recent cluster expansion bounds by Poghosyan and Ueltschi (J. Math. Phys. 50:053509, 2009), which are related to the work of Procacci (J. Stat. Phys. 129:171, 2007) and the tree-graph identity, detailed by Brydges (Phénomènes Critiques, Systèmes Aléatoires, Théories de Jauge. Les Houches 1984, pp. 129-183, 1986). The bounds achieved by Lebowitz and Penrose can also be sharpened by doing the actual optimisation and achieving expressions in terms of the Lambert W-function. The different bound from the cluster expansion shows some improvements for bounds on the convergence of the virial expansion in the case of positive potentials, which are allowed to have a hard core.

Allometric relationship and biomass expansion factors (BEFs) for above- and below-ground biomass prediction and stem volume estimation for ash (Fraxinus excelsior L.) and oak (Quercus robur L.)

Czech Academy of Sciences Publication Activity Database

Krejza, Jan; Světlík, J.; Bednář, P.

2017-01-01

Roč. 31, č. 4 (2017), s. 1303-1316 ISSN 0931-1890 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : floodplain forest * root biomass * leaf biomass * branch biomass * shoot biomass * Allometry * stem volume * biomass expansion factor Subject RIV: GK - Forestry OBOR OECD: Forestry Impact factor: 1.842, year: 2016

Epidermal growth factor regulation of glutathione S-transferase gene expression in the rat is mediated by class Pi glutathione S-transferase enhancer I.

Science.gov (United States)

Matsumoto, M; Imagawa, M; Aoki, Y

2000-07-01

Using chloramphenicol acetyltransferase assays we showed that epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha), and 3,3',4,4',5-pentachlorobiphenyl (PenCB) induce class Pi glutathione S-transferase (GSTP1) in primary cultured rat liver parenchymal cells. GSTP1 enhancer I (GPEI), which is required for the stimulation of GSTP1 expression by PenCB, also mediates EGF and TGF alpha stimulation of GSTP1 gene expression. However, hepatocyte growth factor and insulin did not stimulate GPEI-mediated gene expression. On the other hand, the antioxidant reagents butylhydroxyanisole and t-butylhydroquinone, stimulated GPEI-mediated gene expression, but the level of GSTP1 mRNA was not elevated. Our observations suggest that EGF and TGF alpha induce GSTP1 by the same signal transduction pathway as PenCB. Since the sequence of GPEI is similar to that of the antioxidant responsive element (ARE), some factors which bind to ARE might play a role in GPEI-mediated gene expression.

Mediating factors in martial arts and combat sports: an analysis of the type of martial art, characteristics, and social background of young participants.

Science.gov (United States)

Vertonghen, Jikkemien; Theeboom, Marc; Pieter, Willy

2014-02-01

To date, most studies regarding the social-psychological effects of martial arts and combat sports (MA&CS) on young people focus on measuring effects without considering mediating factors. The aim of the present study was to analyze three mediating factors that might be influential when examining outcomes of MA&CS for youth (i.e., the type of MA&CS, participants' characteristics, and social background). Young MA&CS participants (N = 477, M age = 14.0 yr., SD = 2.13) practicing judo, aikido, kick-/Thai boxing or karate, as well as their parents (N = 307), were assessed in terms of their goal orientations, aggressiveness, psychosocial behavior, and social background. It was concluded that differences exist in the characteristics and social background of participants depending on the type of MA&CS being practiced. The fact that differences in these mediating factors can be identified indicates that in future research these and possible other mediating factors should be considered when trying to determine social-psychological outcomes of MA&CS.

Multipole expansion of vertex functions in an arbitrary frame

International Nuclear Information System (INIS)

Daumens, Michel

1977-01-01

Vertex functions are expanded on the bases of tensor spherical harmonics and tensor multipoles. The coefficients of the expansions are rotational invariant form factors. The relations with those defined in particular frames by Durand, De Celles and Marr, and by De Rafael are exhibited. Finally multipolar form factors are built which are irreducible under pure Lorentz transformations [fr

Provincial hydro expansions

Energy Technology Data Exchange (ETDEWEB)

Froschauer, K J

1993-01-01

A study of the development of five provincial hydroelectric utilities in Canada indicates that power companies and the state invited manufacturers to use hydroelectricity and natural resources in order to diversify provincial economies. These hydro expansions also show that utilities and government designed hydro projects to serve continental requirements; serving both objectives became problematic. It is argued that when the Canadian state and firms such as utilities use hydro expansions to serve both continentalism and industrialization, then at best they foster dependent industrialization and staple processing. At worst, they overbuild the infrastructure to generate provincial surplus energy for continental, rather than national, integration. Hydro developments became subject to state intervention in Canada mainly through the failures of private utilities to provide power for the less-lucrative industrial markets within provincial subregions. Although the state and utilities invited foreign firms to manufacture hydro equipment within the provinces and others to use electricity to diversify production beyond resource processing, such a diversification did not occur. Since 1962, ca 80% of industrial energy was used to semi-process wood-derived products, chemicals, and metals. The idea for a national power network became undermined by interprovincial political-economic factors and since 1963, the federal national/continential power policy prevailed. 187 refs., 6 figs., 52 tabs.

Computer-Mediated Collaborative Projects: Processes for Enhancing Group Development

Science.gov (United States)

Dupin-Bryant, Pamela A.

2008-01-01

Groups are a fundamental part of the business world. Yet, as companies continue to expand internationally, a major challenge lies in promoting effective communication among employees who work in varying time zones. Global expansion often requires group collaboration through computer systems. Computer-mediated groups lead to different communicative…

Ultra-low thermal expansion realized in giant negative thermal expansion materials through self-compensation

Science.gov (United States)

Shen, Fei-Ran; Kuang, Hao; Hu, Feng-Xia; Wu, Hui; Huang, Qing-Zhen; Liang, Fei-Xiang; Qiao, Kai-Ming; Li, Jia; Wang, Jing; Liu, Yao; Zhang, Lei; He, Min; Zhang, Ying; Zuo, Wen-Liang; Sun, Ji-Rong; Shen, Bao-Gen

2017-10-01

Materials with zero thermal expansion (ZTE) or precisely tailored thermal expansion are in urgent demand of modern industries. However, the overwhelming majority of materials show positive thermal expansion. To develop ZTE or negative thermal expansion (NTE) materials as compensators has become an important challenge. Here, we present the evidence for the realization of ultra-low thermal expansion in Mn-Co-Ge-In particles. The bulk with the Ni2In-type hexagonal structure undergoes giant NTE owing to a martensitic magnetostructural transition. The major finding is that the thermal expansion behavior can be totally controlled by modulating the crystallinity degree and phase transition from atomic scale. Self-compensation effect leads to ultra-low thermal expansion with a linear expansion coefficient as small as +0.68 × 10-6/K over a wide temperature range around room temperature. The present study opens an avenue to reach ZTE particularly from the large class of giant NTE materials based on phase transition.

Ultra-low thermal expansion realized in giant negative thermal expansion materials through self-compensation

Directory of Open Access Journals (Sweden)

Fei-Ran Shen

2017-10-01

Full Text Available Materials with zero thermal expansion (ZTE or precisely tailored thermal expansion are in urgent demand of modern industries. However, the overwhelming majority of materials show positive thermal expansion. To develop ZTE or negative thermal expansion (NTE materials as compensators has become an important challenge. Here, we present the evidence for the realization of ultra-low thermal expansion in Mn–Co–Ge–In particles. The bulk with the Ni2In-type hexagonal structure undergoes giant NTE owing to a martensitic magnetostructural transition. The major finding is that the thermal expansion behavior can be totally controlled by modulating the crystallinity degree and phase transition from atomic scale. Self-compensation effect leads to ultra-low thermal expansion with a linear expansion coefficient as small as +0.68 × 10−6/K over a wide temperature range around room temperature. The present study opens an avenue to reach ZTE particularly from the large class of giant NTE materials based on phase transition.

Neonatal plasma polarizes TLR4-mediated cytokine responses towards low IL-12p70 and high IL-10 production via distinct factors.

Directory of Open Access Journals (Sweden)

Mirjam E Belderbos

Full Text Available Human neonates are highly susceptible to infection, which may be due in part to impaired innate immune function. Neonatal Toll-like receptor (TLR responses are biased against the generation of pro-inflammatory/Th1-polarizing cytokines, yet the underlying mechanisms are incompletely defined. Here, we demonstrate that neonatal plasma polarizes TLR4-mediated cytokine production. When exposed to cord blood plasma, mononuclear cells (MCs produced significantly lower TLR4-mediated IL-12p70 and higher IL-10 compared to MC exposed to adult plasma. Suppression by neonatal plasma of TLR4-mediated IL-12p70 production, but not induction of TLR4-mediated IL-10 production, was maintained up to the age of 1 month. Cord blood plasma conferred a similar pattern of MC cytokine responses to TLR3 and TLR8 agonists, demonstrating activity towards both MyD88-dependent and MyD88-independent agonists. The factor causing increased TLR4-mediated IL-10 production by cord blood plasma was heat-labile, lost after protein depletion and independent of lipoprotein binding protein (LBP or soluble CD14 (sCD14. The factor causing inhibition of TLR4-mediated IL-12p70 production by cord blood plasma was resistant to heat inactivation or protein depletion and was independent of IL-10, vitamin D and prostaglandin E2. In conclusion, human neonatal plasma contains at least two distinct factors that suppress TLR4-mediated IL-12p70 production or induce IL-10 or production. Further identification of these factors will provide insight into the ontogeny of innate immune development and might identify novel targets for the prevention and treatment of neonatal infection.

Neonatal Plasma Polarizes TLR4-Mediated Cytokine Responses towards Low IL-12p70 and High IL-10 Production via Distinct Factors

Science.gov (United States)

Belderbos, Mirjam E.; Levy, Ofer; Stalpers, Femke; Kimpen, Jan L.; Meyaard, Linde; Bont, Louis

2012-01-01

Human neonates are highly susceptible to infection, which may be due in part to impaired innate immune function. Neonatal Toll-like receptor (TLR) responses are biased against the generation of pro-inflammatory/Th1-polarizing cytokines, yet the underlying mechanisms are incompletely defined. Here, we demonstrate that neonatal plasma polarizes TLR4-mediated cytokine production. When exposed to cord blood plasma, mononuclear cells (MCs) produced significantly lower TLR4-mediated IL-12p70 and higher IL-10 compared to MC exposed to adult plasma. Suppression by neonatal plasma of TLR4-mediated IL-12p70 production, but not induction of TLR4-mediated IL-10 production, was maintained up to the age of 1 month. Cord blood plasma conferred a similar pattern of MC cytokine responses to TLR3 and TLR8 agonists, demonstrating activity towards both MyD88-dependent and MyD88-independent agonists. The factor causing increased TLR4-mediated IL-10 production by cord blood plasma was heat-labile, lost after protein depletion and independent of lipoprotein binding protein (LBP) or soluble CD14 (sCD14). The factor causing inhibition of TLR4-mediated IL-12p70 production by cord blood plasma was resistant to heat inactivation or protein depletion and was independent of IL-10, vitamin D and prostaglandin E2. In conclusion, human neonatal plasma contains at least two distinct factors that suppress TLR4-mediated IL-12p70 production or induce IL-10 or production. Further identification of these factors will provide insight into the ontogeny of innate immune development and might identify novel targets for the prevention and treatment of neonatal infection. PMID:22442690

Ultra-low thermal expansion realized in giant negative thermal expansion materials through self-compensation

OpenAIRE

Fei-Ran Shen; Hao Kuang; Feng-Xia Hu; Hui Wu; Qing-Zhen Huang; Fei-Xiang Liang; Kai-Ming Qiao; Jia Li; Jing Wang; Yao Liu; Lei Zhang; Min He; Ying Zhang; Wen-Liang Zuo; Ji-Rong Sun

2017-01-01

Materials with zero thermal expansion (ZTE) or precisely tailored thermal expansion are in urgent demand of modern industries. However, the overwhelming majority of materials show positive thermal expansion. To develop ZTE or negative thermal expansion (NTE) materials as compensators has become an important challenge. Here, we present the evidence for the realization of ultra-low thermal expansion in Mn–Co–Ge–In particles. The bulk with the Ni2In-type hexagonal structure undergoes giant NTE o...

Transcription factor Sox4 is required for PUMA-mediated apoptosis induced by histone deacetylase inhibitor, TSA.

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Jang, Sang-Min; Kang, Eun-Jin; Kim, Jung-Woong; Kim, Chul-Hong; An, Joo-Hee; Choi, Kyung-Hee

2013-08-23

PUMA is a crucial regulator of apoptotic cell death mediated by p53-dependent and p53-independent mechanisms. In many cancer cells, PUMA expression is induced in response to DNA-damaging reagent in a p53-dependent manner. However, few studies have investigated transcription factors that lead to the induction of PUMA expression via p53-independent apoptotic signaling. In this study, we found that the transcription factor Sox4 increased PUMA expression in response to trichostatin A (TSA), a histone deacetylase inhibitor in the p53-null human lung cancer cell line H1299. Ectopic expression of Sox4 led to the induction of PUMA expression at the mRNA and protein levels, and TSA-mediated up-regulation of PUMA transcription was repressed by the knockdown of Sox4. Using luciferase assays and chromatin immunoprecipitation, we also determined that Sox4 recruits p300 on the PUMA promoter region and increases PUMA gene expression in response to TSA treatment. Taken together, these results suggest that Sox4 is required for p53-independent apoptotic cell death mediated by PUMA induction via TSA treatment. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

Cost of Incremental Expansion of an Existing Family Medicine Residency Program.

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Ashkin, Evan A; Newton, Warren P; Toomey, Brian; Lingley, Ronald; Page, Cristen P

2017-07-01

Expanding residency training programs to address shortages in the primary care workforce is challenged by the present graduate medical education (GME) environment. The Medicare funding cap on new GME positions and reductions in the Health Resources and Services Administration (HRSA) Teaching Health Center (THC) GME program require innovative solutions to support primary care residency expansion. Sparse literature exists to assist in predicting the actual cost of incremental expansion of a family medicine residency program without federal or state GME support. In 2011 a collaboration to develop a community health center (CHC) academic medical partnership (CHAMP), was formed and created a THC as a training site for expansion of an existing family medicine residency program. The cost of expansion was a critical factor as no Federal GME funding or HRSA THC GME program support was available. Initial start-up costs were supported by a federal grant and local foundations. Careful financial analysis of the expansion has provided actual costs per resident of the incremental expansion of the residencyRESULTS: The CHAMP created a new THC and expanded the residency from eight to ten residents per year. The cost of expansion was approximately $72,000 per resident per year. The cost of incremental expansion of our residency program in the CHAMP model was more than 50% less than that of the recently reported cost of training in the HRSA THC GME program.

Thermal expansion of granite rocks

International Nuclear Information System (INIS)

Stephansson, O.

1978-04-01

The thermal expansion of rocks is strongly controlled by the thermal expansion of the minerals. The theoretical thermal expansion of the Stripa Granite is gound to be 21 . 10 -6 [deg C] -1 at 25 deg C and 38 . 10 -6 [deg C] -1 at 400 deg C. The difference in expansion for the rock forming minerals causes micro cracking at heating. The expansion due to micro cracks is found to be of the same order as the mineral expansion. Most of the micro cracks will close at pressures of the order of 10 - 20 MPa. The thermal expansion of a rock mass including the effect of joints is determined in the pilot heater test in the Stripa Mine

Trinucleon wave functions from separable expansions of the N-N interaction

International Nuclear Information System (INIS)

Birrell, N.D.

1976-09-01

This work is intended to determine whether a separable expansion for the N-N interaction can be used to obtain trinucleon wave functions of high quality. The expansions used in the study are the Unitary Pole expansion of Harms, Afnan and Read, and the expansion of Adhikari and Sloan. We first compare the calculation of the RSC potential Triton binding energy with the two methods, and find that the results agree quite closely. However, while it is found necessary to use t-matrix perturbation theory to obtain the UPE result, such is not the case with the ASE, thus offering a considerable improvement on the previously used method. We then proceed to calculate the L-S coupling probabilities for the wave function, and in so doing, discover a source of inaccuracy in the work of other authors. We also find that the UPE and ASE give probabilities in good agreement with one another. The calculation of the He 3 charge form factor turns out to be the most critical judge of the accuracy of the wave function. Although both expansions give quite satisfactory results for the charge form factor, those obtained with the ASE are exceptionally pleasing. We finally apply both methods to the OBEP of Holinde and Machleidt, and find that the UPE is quite unsuitable for such application. The ASE, however, once again gives very good results, indicating the high quality of the trinucleon wave function obtained with it. (author)

The Mediator Kinase Module Restrains Epidermal Growth Factor Receptor Signaling and Represses Vulval Cell Fate Specification in Caenorhabditis elegans.

Science.gov (United States)

Grants, Jennifer M; Ying, Lisa T L; Yoda, Akinori; You, Charlotte C; Okano, Hideyuki; Sawa, Hitoshi; Taubert, Stefan

2016-02-01

Cell signaling pathways that control proliferation and determine cell fates are tightly regulated to prevent developmental anomalies and cancer. Transcription factors and coregulators are important effectors of signaling pathway output, as they regulate downstream gene programs. In Caenorhabditis elegans, several subunits of the Mediator transcriptional coregulator complex promote or inhibit vulva development, but pertinent mechanisms are poorly defined. Here, we show that Mediator's dissociable cyclin dependent kinase 8 (CDK8) module (CKM), consisting of cdk-8, cic-1/Cyclin C, mdt-12/dpy-22, and mdt-13/let-19, is required to inhibit ectopic vulval cell fates downstream of the epidermal growth factor receptor (EGFR)-Ras-extracellular signal-regulated kinase (ERK) pathway. cdk-8 inhibits ectopic vulva formation by acting downstream of mpk-1/ERK, cell autonomously in vulval cells, and in a kinase-dependent manner. We also provide evidence that the CKM acts as a corepressor for the Ets-family transcription factor LIN-1, as cdk-8 promotes transcriptional repression by LIN-1. In addition, we find that CKM mutation alters Mediator subunit requirements in vulva development: the mdt-23/sur-2 subunit, which is required for vulva development in wild-type worms, is dispensable for ectopic vulva formation in CKM mutants, which instead display hallmarks of unrestrained Mediator tail module activity. We propose a model whereby the CKM controls EGFR-Ras-ERK transcriptional output by corepressing LIN-1 and by fine tuning Mediator specificity, thus balancing transcriptional repression vs. activation in a critical developmental signaling pathway. Collectively, these data offer an explanation for CKM repression of EGFR signaling output and ectopic vulva formation and provide the first evidence of Mediator CKM-tail module subunit crosstalk in animals. Copyright © 2016 by the Genetics Society of America.

Insulin like growth factor-1/insulin bypasses Pref-1/FA1-mediated inhibition of adipocyte differentiation

DEFF Research Database (Denmark)

Zhang, Hongbin; Nøhr, Jane; Jensen, Charlotte Harken

2003-01-01

that forced expression of the soluble form, FA1, or full-length Pref-1 did not inhibit adipocyte differentiation of 3T3-L1 cells when differentiation was induced by standard treatment with methylisobutylxanthine, dexamethasone, and high concentrations of insulin. However, forced expression of either form...... of Pref-1/FA1 in 3T3-L1 or 3T3-F442A cells inhibited adipocyte differentiation when insulin or insulin-like growth factor-1 (IGF-1) was omitted from the differentiation mixture. We demonstrate that the level of the mature form of the IGF-1 receptor is reduced and that IGF-1-dependent activation of p42/p44...... mitogen-activated protein kinases (MAPKs) is compromised in preadipocytes with forced expression of Pref-1. This is accompanied by suppression of clonal expansion and terminal differentiation. Accordingly, supplementation with insulin or IGF-1 rescued p42/p44 MAPK activation, clonal expansion...

Cell-cell adhesion mediated by binding of membrane-anchored transforming growth factor α to epidermal growth factor receptors promotes cell proliferation

International Nuclear Information System (INIS)

Anklesaria, P.; Greenberger, J.S.; Teixido, J.; Laiho, M.; Massague, J.; Pierce, J.H.

1990-01-01

The precursor for transforming growth factor α, pro-TGF-α, is a cell surface glycoprotein that can establish contact with epidermal growth factor (EGF) receptors on adjacent cells. To examine whether the pro-TGF-α/EGF receptor pair can simultaneously mediate cell adhesion and promote cell proliferation, the authors have expressed pro-TGF-α in a bone marrow stromal cell line labeled with [ 35 S] cysteine. Expression of pro-TGF-α allows these cells to support long-term attachment of an EGF/interleukin-3-dependent hematopoietic progenitor cell line that expresses EGF receptors but is unable to adhere to normal stroma. This interaction is inhibited by soluble EGF receptor ligands. Further, the hematopoietic progenitor cells replicate their DNA while they are attached to the stromal cell layer and become foci of sustained cell proliferation. Thus, pro-TGF-α and the EGF receptor can function as mediators of intercellular adhesion and this interaction may promote a mitogenic response. They propose the term juxtacrine to designate this form of stimulation between adjacent cells

Formulation of Low Peclet Number Based Grid Expansion Factor for the Solution of the Convection Diffusion Equation

Directory of Open Access Journals (Sweden)

A. Abdullah

2018-04-01

Full Text Available Convection-diffusion problems, due to its fundamental nature, are found in various science and engineering applications. In this research, the importance of the relationship between grid structure and flow parameters in such problems is emphasized. In particular, we propose a systematic technique in the selection of the grid expansion factor based on its logarithmic relationship with low Peclet number. Such linear mathematical connection between the two non-dimensional parameters serves as a guideline for more structured decision-making and improves the heuristic process in the determination of the computational domain grid for the numerical solution of convection-diffusion equations especially in the prediction of the concentration of the scalar. Results confirm the effectiveness of the new approach.

Connective tissue growth factor mediates TGF-β1-induced low-grade serous ovarian tumor cell apoptosis.

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Cheng, Jung-Chien; Chang, Hsun-Ming; Leung, Peter C K

2017-10-17

Ovarian low-grade serous carcinoma (LGSC) is a rare disease and is now considered to be a distinct entity from high-grade serous carcinoma (HGSC), which is the most common and malignant form of epithelial ovarian cancer. Connective tissue growth factor (CTGF) is a secreted matricellular protein that has been shown to modulate many biological functions by interacting with multiple molecules in the microenvironment. Increasing evidence indicates that aberrant expression of CTGF is associated with cancer development and progression. Transforming growth factor-β1 (TGF-β1) is a well-known molecule that can strongly up-regulate CTGF expression in different types of normal and cancer cells. Our previous study demonstrated that TGF-β1 induces apoptosis of LGSC cells. However, the effect of TGF-β1 on CTGF expression in LGSC needs to be defined. In addition, whether CTGF mediates TGF-β1-induced LGSC cell apoptosis remains unknown. In the present study, we show that TGF-β1 treatment up-regulates CTGF expression by activating SMAD3 signaling in two human LGSC cell lines. Additionally, siRNA-mediated CTGF knockdown attenuates TGF-β1-induced cell apoptosis. Moreover, our results show that the inhibitory effect of the CTGF knockdown on TGF-β1-induced cell apoptosis is mediated by down-regulating SMAD3 expression. This study demonstrates an important role for CTGF in mediating the pro-apoptotic effects of TGF-β1 on LGCS.

Mediators of exposure therapy for youth obsessive-compulsive disorder: specificity and temporal sequence of client and treatment factors.

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Chu, Brian C; Colognori, Daniela B; Yang, Guang; Xie, Min-ge; Lindsey Bergman, R; Piacentini, John

2015-05-01

Behavioral engagement and cognitive coping have been hypothesized to mediate effectiveness of exposure-based therapies. Identifying which specific child factors mediate successful therapy and which therapist factors facilitate change can help make our evidence-based treatments more efficient and robust. The current study examines the specificity and temporal sequence of relations among hypothesized client and therapist mediators in exposure therapy for pediatric Obsessive Compulsive Disorder (OCD). Youth coping (cognitive, behavioral), youth safety behaviors (avoidance, escape, compulsive behaviors), therapist interventions (cognitive, exposure extensiveness), and youth anxiety were rated via observational ratings of therapy sessions of OCD youth (N=43; ages=8 - 17; 62.8% male) who had received Exposure and Response Prevention (ERP). Regression analysis using Generalized Estimation Equations and cross-lagged panel analysis (CLPA) were conducted to model anxiety change within and across sessions, to determine formal mediators of anxiety change, and to establish sequence of effects. Anxiety ratings decreased linearly across exposures within sessions. Youth coping and therapist interventions significantly mediated anxiety change across exposures, and youth-interfering behavior mediated anxiety change at the trend level. In CLPA, youth-interfering behaviors predicted, and were predicted by, changes in anxiety. Youth coping was predicted by prior anxiety change. The study provides a preliminary examination of specificity and temporal sequence among child and therapist behaviors in predicting youth anxiety. Results suggest that therapists should educate clients in the natural rebound effects of anxiety between sessions and should be aware of the negatively reinforcing properties of avoidance during exposure. Copyright © 2015. Published by Elsevier Ltd.

Expansion planning for electrical generating systems

International Nuclear Information System (INIS)

1984-01-01

The guidebook outlines the general principles of electric power system planning in the context of energy and economic planning in general. It describes the complexities of electric system expansion planning that are due to the time dependence of the problem and the interrelation between the main components of the electric system (generation, transmission and distribution). Load forecasting methods are discussed and the principal models currently used for electric system expansion planning presented. Technical and economic information on power plants is given. Constraints imposed on power system planning by plant characteristics (particularly nuclear power plants) are discussed, as well as factors such as transmission system development, environmental considerations, availability of manpower and financial resources that may affect the proposed plan. A bibliography supplements the references that appear in each chapter, and a comprehensive glossary defines terms used in the guidebook

Platelet-activating factor receptor agonists mediate xeroderma pigmentosum A photosensitivity.

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Yao, Yongxue; Harrison, Kathleen A; Al-Hassani, Mohammed; Murphy, Robert C; Rezania, Samin; Konger, Raymond L; Travers, Jeffrey B

2012-03-16

To date, oxidized glycerophosphocholines (Ox-GPCs) with platelet-activating factor (PAF) activity produced non-enzymatically have not been definitively demonstrated to mediate any known disease processes. Here we provide evidence that these Ox-GPCs play a pivotal role in the photosensitivity associated with the deficiency of the DNA repair protein xeroderma pigmentosum type A (XPA). It should be noted that XPA-deficient cells are known to have decreased antioxidant defenses. These studies demonstrate that treatment of human XPA-deficient fibroblasts with the pro-oxidative stressor ultraviolet B (UVB) radiation resulted in increased reactive oxygen species and PAF receptor (PAF-R) agonistic activity in comparison with gene-corrected cells. The UVB irradiation-generated PAF-R agonists were inhibited by antioxidants. UVB irradiation of XPA-deficient (Xpa-/-) mice also resulted in increased PAF-R agonistic activity and skin inflammation in comparison with control mice. The increased UVB irradiation-mediated skin inflammation and TNF-α production in Xpa-/- mice were blocked by systemic antioxidants and by PAF-R antagonists. Structural characterization of PAF-R-stimulating activity in UVB-irradiated XPA-deficient fibroblasts using mass spectrometry revealed increased levels of sn-2 short-chain Ox-GPCs along with native PAF. These studies support a critical role for PAF-R agonistic Ox-GPCs in the pathophysiology of XPA photosensitivity.

Does empowerment mediate the effects of psychological factors on mental health, well-being, and recovery in young people?

Science.gov (United States)

Grealish, Annmarie; Tai, Sara; Hunter, Andrew; Emsley, Richard; Murrells, Trevor; Morrison, Anthony P

2017-09-01

There is consensus that empowerment is key to recovery from mental health problems, enabling a person to take charge of their life and make informed choices and decisions about their life. However, little is known about the mechanisms through which empowerment affects mental health in young people. The current study involved young people aged 16-29 years and examined empowerment as a potential mediator of the relationship between psychological factors (psychosocial, cognition, coping, and control) and mental health, well-being, and recovery from personal problems. A cross-sectional, Internet-based questionnaire study recruited 423 young people aged between 16 and 29 attending universities in England (n = 336) and Ireland (n = 87). Psychological factors, mental well-being, empowerment, and recovery from personal problems were measured using self-report measures. Mediation analysis in both the single and one over-arching mediator models revealed that empowerment mediates the relationship between psychological factors (psychosocial, self-efficacy, thinking style, coping, and control) and mental health, well-being, and recovery from general life problems. This study demonstrates the importance of empowerment, showing that it mediates the relationship between psychological processes and mental health, well-being, and recovery in young people. Clinical implications for working with young people within mental health services, and facilitating their empowerment are discussed. Empowerment is currently a poorly defined concept. This study demonstrates how empowerment mediates the relationship between psychological processes and mental health, well-being, and recovery in young people. Clinicians working with young people might benefit from a structured means of understanding and assessing the different ways in which individuals manage their thinking styles. Empowerment in young people is influenced by the manner in which clinicians facilitate them in establishing social

Gendered Pathways? Gender, Mediating Factors, and the Gap in Boys' and Girls' Substance Use

Science.gov (United States)

Whaley, Rachel Bridges; Hayes-Smith, Justin; Hayes-Smith, Rebecca

2013-01-01

A gender gap in alcohol and drug use exists but is somewhat smaller than the gender gap in other forms of delinquency. This article extends studies that examine the gender-delinquency relationship to substance use in particular and estimate the extent to which major risk and protective factors mediate the association between gender and alcohol and…

Cysteine protease antigens cleave CD123, the α subunit of murine IL-3 receptor, on basophils and suppress IL-3-mediated basophil expansion

International Nuclear Information System (INIS)

Nishikado, Hideto; Fujimura, Tsutomu; Taka, Hikari; Mineki, Reiko; Ogawa, Hideoki; Okumura, Ko; Takai, Toshiro

2015-01-01

Th2 type immune responses are essential for protective immunity against parasites and play crucial roles in allergic disorders. Helminth parasites secrete a variety of proteases for their infectious cycles including for host entry, tissue migration, and suppression of host immune effector cell function. Furthermore, a number of pathogen-derived antigens, as well as allergens such as papain, belong to the family of cysteine proteases. Although the link between protease activity and Th2 type immunity is well documented, the mechanisms by which proteases regulate host immune responses are largely unknown. Here, we demonstrate that the cysteine proteases papain and bromelain selectively cleave the α subunit of the IL-3 receptor (IL-3Rα/CD123) on the surface of murine basophils. The decrease in CD123 expression on the cell surface, and the degradation of the extracellular domain of recombinant CD123 were dependent on the protease activity of papain and bromelain. Pre-treatment of murine basophils with papain resulted in inhibition of IL-3-IL-3R signaling and suppressed IL-3- but not thymic stromal lymphopoietin-induced expansion of basophils in vitro. Our unexpected findings illuminate a novel mechanism for the regulation of basophil functions by protease antigens. Because IL-3 plays pivotal roles in the activation and proliferation of basophils and in protective immunity against helminth parasites, pathogen-derived proteases might contribute to the pathogenesis of infections by regulating IL-3-mediated functions in basophils. - Highlights: • We identified the murine IL3R as a novel target of papain-family cysteine proteases. • Papain-family cysteine proteases cleaved IL3Rα/CD123 on murine basophils. • Papain suppressed IL3- but not TSLP-induced expansion of murine basophils. • The inactivation of IL3R might be a strategy for pathogens to suppress host immunity

Cysteine protease antigens cleave CD123, the α subunit of murine IL-3 receptor, on basophils and suppress IL-3-mediated basophil expansion

Energy Technology Data Exchange (ETDEWEB)

Nishikado, Hideto [Atopy (Allergy) Research Center, Juntendo University Graduate School of Medicine, Tokyo (Japan); Fujimura, Tsutomu; Taka, Hikari; Mineki, Reiko [Laboratory of Proteomics and Biomolecular Science, BioMedical Research Center, Juntendo University Graduate School of Medicine, Tokyo (Japan); Ogawa, Hideoki; Okumura, Ko [Atopy (Allergy) Research Center, Juntendo University Graduate School of Medicine, Tokyo (Japan); Takai, Toshiro, E-mail: t-takai@juntendo.ac.jp [Atopy (Allergy) Research Center, Juntendo University Graduate School of Medicine, Tokyo (Japan)

2015-05-01

Th2 type immune responses are essential for protective immunity against parasites and play crucial roles in allergic disorders. Helminth parasites secrete a variety of proteases for their infectious cycles including for host entry, tissue migration, and suppression of host immune effector cell function. Furthermore, a number of pathogen-derived antigens, as well as allergens such as papain, belong to the family of cysteine proteases. Although the link between protease activity and Th2 type immunity is well documented, the mechanisms by which proteases regulate host immune responses are largely unknown. Here, we demonstrate that the cysteine proteases papain and bromelain selectively cleave the α subunit of the IL-3 receptor (IL-3Rα/CD123) on the surface of murine basophils. The decrease in CD123 expression on the cell surface, and the degradation of the extracellular domain of recombinant CD123 were dependent on the protease activity of papain and bromelain. Pre-treatment of murine basophils with papain resulted in inhibition of IL-3-IL-3R signaling and suppressed IL-3- but not thymic stromal lymphopoietin-induced expansion of basophils in vitro. Our unexpected findings illuminate a novel mechanism for the regulation of basophil functions by protease antigens. Because IL-3 plays pivotal roles in the activation and proliferation of basophils and in protective immunity against helminth parasites, pathogen-derived proteases might contribute to the pathogenesis of infections by regulating IL-3-mediated functions in basophils. - Highlights: • We identified the murine IL3R as a novel target of papain-family cysteine proteases. • Papain-family cysteine proteases cleaved IL3Rα/CD123 on murine basophils. • Papain suppressed IL3- but not TSLP-induced expansion of murine basophils. • The inactivation of IL3R might be a strategy for pathogens to suppress host immunity.

Studying influence of two effective parameters on network losses in transmission expansion planning using DCGA

International Nuclear Information System (INIS)

Shayeghi, H.; Jalilzadeh, S.; Mahdavi, M.; Hadadian, H.

2008-01-01

Transmission network expansion planning (TNEP) is a basic part of power network planning that determines where, when and how many new transmission lines should be added to the network. Its task is to minimize the network construction and operational cost, while meeting imposed technical, economic and reliability constraints. Up till now, various methods have been proposed for solution of the static transmission network expansion planning (STNEP) problem. But, in all of them, the effect of two important parameters i.e., inflation rate and load growth factor on network losses has not been investigated. Thus, in this paper, STNEP is being studied considering the effect of inflation rate and load growth factor on the network losses in a transmission network with different voltage levels using a decimal codification genetic algorithm (DCGA). The effectiveness of the proposed idea is tested on the Garver's six-bus network. The results evaluation reveals that the inflation rate and load growth factor have important effect on the network losses and subsequent network arrangement. In addition, considering the effect of two above-mentioned parameters (inflation rate and load growth factor) in expansion planning of transmission networks with various line voltage levels is caused that the total expansion cost of the network (expansion costs and the operational cost) is calculated more exactly and therefore the network satisfies the requirements of delivering electric power more safely and reliably to load centers

Adenovirus E4-ORF1 Dysregulates Epidermal Growth Factor and Insulin/Insulin-Like Growth Factor Receptors To Mediate Constitutive Myc Expression

OpenAIRE

Kong, Kathleen; Kumar, Manish; Taruishi, Midori; Javier, Ronald T.

2015-01-01

The E4-ORF1 protein encoded by human adenovirus stimulates viral replication in human epithelial cells by binding and activating cellular phosphatidylinositol 3-kinase (PI3K) at the plasma membrane and cellular Myc in the nucleus. In this study, we showed that E4-ORF1 hijacks the tyrosine kinase activities of cellular epidermal growth factor receptor (EGFR) and insulin receptor (InsR)/insulin-like growth factor receptor 1 (IGF1R), as well as the lipid kinase activity of PI3K, to mediate const...

The Applicability of Cognitive Mediational and Moderational Models to Explain Children's Depression Inventory Factor Scores in Urban Youth

Science.gov (United States)

Reinemann, Dawn H. S.; Teeter Ellison, Phyllis A.

2004-01-01

This investigation examined whether cognition serves as a direct factor, mediates, or moderates the relationship between stressful life events and Children's Depression Inventory (CDI; Kovacs, 1992) factor scores in urban, ethnic minority youth. Ninety-eight middle school students completed measures of stressful life events, cognition (cognitive…

Hierarchical mechanisms for transcription factor-mediated reprogramming of fibroblasts to neurons

Science.gov (United States)

Wapinski, Orly L.; Vierbuchen, Thomas; Qu, Kun; Lee, Qian Yi; Chanda, Soham; Fuentes, Daniel R.; Giresi, Paul G.; Ng, Yi Han; Marro, Samuele; Neff, Norma F.; Drechsel, Daniela; Martynoga, Ben; Castro, Diogo S.; Webb, Ashley E.; Brunet, Anne; Guillemot, Francois; Chang, Howard Y.; Wernig, Marius

2013-01-01

SUMMARY Direct lineage reprogramming is a promising approach for human disease modeling and regenerative medicine with poorly understood mechanisms. Here we reveal a hierarchical mechanism in the direct conversion of fibroblasts into induced neuronal (iN) cells mediated by the transcription factors Ascl1, Brn2, and Myt1l. Ascl1 acts as an “on target” pioneer factor by immediately occupying most cognate genomic sites in fibroblasts. In contrast, Brn2 and Myt1l do not access fibroblast chromatin productively on their own; instead Ascl1 recruits Brn2 to Ascl1 sites genome-wide. A unique trivalent chromatin signature in the host cells predicts the permissiveness for Ascl1 pioneering activity among different cell types. Finally, we identified Zfp238 as a key Ascl1 target gene that can partially substitute for Ascl1 during iN cell reprogramming. Thus, precise match between pioneer factor and the chromatin context at key target genes is determinative for trans-differentiation to neurons and likely other cell types. PMID:24243019

Sensitivity analysis in electric system expansion planning study using DECADES

International Nuclear Information System (INIS)

Perez Martin, D.; Lopez Lopez, I.

1998-01-01

To cover the increasing electricity demand as a key economic and social factor of development, it is necessary to have adequate expansion police. The delay in installation of certain capabilities produces electricity deficit. In other hand, construction of oversized capacities generates excessive costs. Therefore it is important to acquire or develop adequate methodologies according to the country specific conditions to carry out electric expansion planning studies. The goal is to chose optimal solutions in order to reach sustainable development using owns energy resources and preserving the environment. In the paper the Decades methodology is used for electricity system expansion planning. Premises and main assumptions for the calculations are presented. Some electric system expansion cases are evaluated. We also present the results of a sensibility study varying the discount rate, loss of load probability energy not served cost, fuel availability and fuel and investment costs. The reliability criteria currently not used in Cuban electric system are evaluated. We discuss the results and display the conclusions and recommendations

Inflammatory cytokine tumor necrosis factor α suppresses neuroprotective endogenous erythropoietin from astrocytes mediated by hypoxia-inducible factor-2α.

Science.gov (United States)

Nagaya, Yoshiaki; Aoyama, Mineyoshi; Tamura, Tetsuya; Kakita, Hiroki; Kato, Shin; Hida, Hideki; Saitoh, Shinji; Asai, Kiyofumi

2014-12-01

Interest in erythropoietin (EPO) as a neuroprotective mediator has grown since it was found that systemically administered EPO is protective in several animal models of disease. However, given that the blood-brain barrier limits EPO entry into the brain, alternative approaches that induce endogenous EPO production in the brain may be more effective clinically and associated with fewer untoward side-effects. Astrocytes are the main source of EPO in the central nervous system. In the present study we investigated the effect of the inflammatory cytokine tumor necrosis factor α (TNFα) on hypoxia-induced upregulation of EPO in rat brain. Hypoxia significantly increased EPO mRNA expression in the brain and kidney, and this increase was suppressed by TNFα in vivo. In cultured astrocytes exposed to hypoxic conditions for 6 and 12 h, TNFα suppressed the hypoxia-induced increase in EPO mRNA expression in a concentration-dependent manner. TNFα inhibition of hypoxia-induced EPO expression was mediated primarily by hypoxia-inducible factor (HIF)-2α rather than HIF-1α. The effects of TNFα in reducing hypoxia-induced upregulation of EPO mRNA expression probably involve destabilization of HIF-2α, which is regulated by the nuclear factor (NF)-κB signaling pathway. TNFα treatment attenuated the protective effects of astrocytes on neurons under hypoxic conditions via EPO signaling. The effective blockade of TNFα signaling may contribute to the maintenance of the neuroprotective effects of EPO even under hypoxic conditions with an inflammatory response. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Resonant state expansions

International Nuclear Information System (INIS)

Lind, P.

1993-02-01

The completeness properties of the discrete set of bound state, virtual states and resonances characterizing the system of a single nonrelativistic particle moving in a central cutoff potential is investigated. From a completeness relation in terms of these discrete states and complex scattering states one can derive several Resonant State Expansions (RSE). It is interesting to obtain purely discrete expansion which, if valid, would significantly simplify the treatment of the continuum. Such expansions can be derived using Mittag-Leffler (ML) theory for a cutoff potential and it would be nice to see if one can obtain the same expansions starting from an eigenfunction theory that is not restricted to a finite sphere. The RSE of Greens functions is especially important, e.g. in the continuum RPA (CRPA) method of treating giant resonances in nuclear physics. The convergence of RSE is studied in simple cases using square well wavefunctions in order to achieve high numerical accuracy. Several expansions can be derived from each other by using the theory of analytic functions and one can the see how to obtain a natural discretization of the continuum. Since the resonance wavefunctions are oscillating with an exponentially increasing amplitude, and therefore have to be interpreted through some regularization procedure, every statement made about quantities involving such states is checked by numerical calculations.Realistic nuclear wavefunctions, generated by a Wood-Saxon potential, are used to test also the usefulness of RSE in a realistic nuclear calculation. There are some fundamental differences between different symmetries of the integral contour that defines the continuum in RSE. One kind of symmetry is necessary to have an expansion of the unity operator that is idempotent. Another symmetry must be used if we want purely discrete expansions. These are found to be of the same form as given by ML. (29 refs.)

Population structure and expansion of kuruma shrimp ( Penaeus ...

African Journals Online (AJOL)

Sequence analyses on the specific intron from the elongation factor-1α gene were conducted to examine the population genetic structure and expansion of kuruma shrimp (Penaeus japonicus) off Taiwan. Five populations including 119 individuals were separately sampled from the north of East China Sea (ECS), west of ...

Impacto de la pobreza en el desarrollo cognitivo: un análisis teórico de dos factores mediadores (Impact of Poverty on Cognitive Development. A Theoretical Analysis of Two Mediator Factors

Directory of Open Access Journals (Sweden)

Cecilia Clara Mazzoni

2014-06-01

Full Text Available RESUMEN: Numerosos estudios han establecido el impacto negativo de la pobreza sobre el desarrollo cognitivo, examinando parcialmente algunos factores mediadores del mismo. El objetivo del presente artículo consiste en realizar un análisis teórico centrado en la estimulación en el hogar y la nutrición como factores mediadores, retomando los resultados de diferentes trabajos desarrollados desde el año 2000. Estos indican que la estimulación en el hogar sería un factor mediador clave del impacto de la pobreza sobre el desarrollo cognitivo, mientras que los efectos del estado nutricional dependerían del grado de severidad del déficit, no siendo determinantes en los casos de desnutrición leve o moderada. Se concluye sobre la importancia teórico-práctica de profundizar en el estudio simultáneo de los factores mediadores implicados. ABSTRACT: Numerous studies have established the negative impact of poverty on cognitive development, by partially examining some mediator factors thereof. The objective of this article is to perform a theoretical analysis focused on home stimulation and nutrition as mediating factors. To do this we took the results of different studies which address this issue, developed since 2000. The results indicate that home stimulation would be a key mediator factor of the impact of poverty on cognitive development, while the effects of nutritional status would depend on the severity of the deficit, not being decisive in cases of mild or moderate undernutrition. We conclude about the theoretical and practical importance of deepen in the simultaneous study of the involved mediators factors.

Meis1 Is Required for Adult Mouse Erythropoiesis, Megakaryopoiesis and Hematopoietic Stem Cell Expansion.

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Michelle Erin Miller

Full Text Available Meis1 is recognized as an important transcriptional regulator in hematopoietic development and is strongly implicated in the pathogenesis of leukemia, both as a Hox transcription factor co-factor and independently. Despite the emerging recognition of Meis1's importance in the context of both normal and leukemic hematopoiesis, there is not yet a full understanding of Meis1's functions and the relevant pathways and genes mediating its functions. Recently, several conditional mouse models for Meis1 have been established. These models highlight a critical role for Meis1 in adult mouse hematopoietic stem cells (HSCs and implicate reactive oxygen species (ROS as a mediator of Meis1 function in this compartment. There are, however, several reported differences between these studies in terms of downstream progenitor populations impacted and effectors of function. In this study, we describe further characterization of a conditional knockout model based on mice carrying a loxP-flanked exon 8 of Meis1 which we crossed onto the inducible Cre localization/expression strains, B6;129-Gt(ROSA26Sor(tm1(Cre/ERTNat/J or B6.Cg-Tg(Mx1-Cre1Cgn/J. Findings obtained from these two inducible Meis1 knockout models confirm and extend previous reports of the essential role of Meis1 in adult HSC maintenance and expansion and provide new evidence that highlights key roles of Meis1 in both megakaryopoiesis and erythropoiesis. Gene expression analyses point to a number of candidate genes involved in Meis1's role in hematopoiesis. Our data additionally support recent evidence of a role of Meis1 in ROS regulation.

Light-induced lattice expansion leads to high-efficiency perovskite solar cells

Energy Technology Data Exchange (ETDEWEB)

Tsai, Hsinhan; Asadpour, Reza; Blancon, Jean-Christophe; Stoumpos, Constantinos C.; Durand, Olivier; Strzalka, Joseph W.; Chen, Bo; Verduzco, Rafael; Ajayan, Pulickel M.; Tretiak, Sergei; Even, Jacky; Alam, Muhammad Ashraf; Kanatzidis, Mercouri G.; Nie, Wanyi; Mohite, Aditya D.

2018-04-05

Hybrid-perovskite based high-performance optoelectronic devices and clues from their operation has led to the realization that light-induced structural dynamics play a vital role on their physical properties, device performance and stability. Here, we report that continuous light illumination leads to a uniform lattice expansion in hybrid perovskite thin-films, which is critical for obtaining high-efficiency photovoltaic devices. Correlated, in-situ structural and device characterizations reveal that light-induced lattice expansion significantly benefits the performances of a mixed-cation pure-halide planar device, boosting the power conversion efficiency from 18.5% to 20.5%. This is a direct consequence of the relaxation of local lattice strains during lattice expansion, which results in the reduction of the energetic barriers at the perovskite/contact interfaces in devices, thus improving the open circuit voltage and fill factor. The light-induced lattice expansion stabilizes these high-efficiency photovoltaic devices under continuous operation of full-spectrum 1-Sun illumination for over 1500 hours. One Sentence Summary: Light-induced lattice expansion improves crystallinity, relaxes lattice strain, which enhances photovoltaic performance in hybrid perovskite device.

Perceptual scale expansion: an efficient angular coding strategy for locomotor space.

Science.gov (United States)

Durgin, Frank H; Li, Zhi

2011-08-01

Whereas most sensory information is coded on a logarithmic scale, linear expansion of a limited range may provide a more efficient coding for the angular variables important to precise motor control. In four experiments, we show that the perceived declination of gaze, like the perceived orientation of surfaces, is coded on a distorted scale. The distortion seems to arise from a nearly linear expansion of the angular range close to horizontal/straight ahead and is evident in explicit verbal and nonverbal measures (Experiments 1 and 2), as well as in implicit measures of perceived gaze direction (Experiment 4). The theory is advanced that this scale expansion (by a factor of about 1.5) may serve a functional goal of coding efficiency for angular perceptual variables. The scale expansion of perceived gaze declination is accompanied by a corresponding expansion of perceived optical slants in the same range (Experiments 3 and 4). These dual distortions can account for the explicit misperception of distance typically obtained by direct report and exocentric matching, while allowing for accurate spatial action to be understood as the result of calibration.

Psychological distress as a mediator in the relationships between biopsychosocial factors and disordered eating among Malaysian university students.

Science.gov (United States)

Gan, Wan Ying; Mohd Nasir, Mohd Taib; Zalilah, Mohd Shariff; Hazizi, Abu Saad

2012-12-01

The mechanism linking biopsychosocial factors to disordered eating among university students is not well understood especially among Malaysians. This study aimed to examine the mediating role of psychological distress in the relationships between biopsychosocial factors and disordered eating among Malaysian university students. A self-administered questionnaire measured self-esteem, body image, social pressures to be thin, weight-related teasing, psychological distress, and disordered eating in 584 university students (59.4% females and 40.6% males). Body weight and height were measured. Structural equation modeling analysis revealed that the partial mediation model provided good fit to the data. Specifically, the relationships between self-esteem and weight-related teasing with disordered eating were mediated by psychological distress. In contrast, only direct relationships between body weight status, body image, and social pressures to be thin with disordered eating were found and were not mediated by psychological distress. Furthermore, multigroup analyses indicated that the model was equivalent for both genders but not for ethnic groups. There was a negative relationship between body weight status and psychological distress for Chinese students, whereas this was not the case among Malay students. Intervention and prevention programs on psychological distress may be beneficial in reducing disordered eating among Malaysian university students. Copyright © 2012 Elsevier Ltd. All rights reserved.

Isotropic Negative Thermal Expansion Metamaterials.

Science.gov (United States)

Wu, Lingling; Li, Bo; Zhou, Ji

2016-07-13

Negative thermal expansion materials are important and desirable in science and engineering applications. However, natural materials with isotropic negative thermal expansion are rare and usually unsatisfied in performance. Here, we propose a novel method to achieve two- and three-dimensional negative thermal expansion metamaterials via antichiral structures. The two-dimensional metamaterial is constructed with unit cells that combine bimaterial strips and antichiral structures, while the three-dimensional metamaterial is fabricated by a multimaterial 3D printing process. Both experimental and simulation results display isotropic negative thermal expansion property of the samples. The effective coefficient of negative thermal expansion of the proposed models is demonstrated to be dependent on the difference between the thermal expansion coefficient of the component materials, as well as on the circular node radius and the ligament length in the antichiral structures. The measured value of the linear negative thermal expansion coefficient of the three-dimensional sample is among the largest achieved in experiments to date. Our findings provide an easy and practical approach to obtaining materials with tunable negative thermal expansion on any scale.

Amplification of TLO Mediator Subunit Genes Facilitate Filamentous Growth in Candida Spp.

Science.gov (United States)

Liu, Zhongle; Moran, Gary P.; Myers, Lawrence C.

2016-01-01

Filamentous growth is a hallmark of C. albicans pathogenicity compared to less-virulent ascomycetes. A multitude of transcription factors regulate filamentous growth in response to specific environmental cues. Our work, however, suggests the evolutionary history of C. albicans that resulted in its filamentous growth plasticity may be tied to a change in the general transcription machinery rather than transcription factors and their specific targets. A key genomic difference between C. albicans and its less-virulent relatives, including its closest relative C. dubliniensis, is the unique expansion of the TLO (TeLOmere-associated) gene family in C. albicans. Individual Tlo proteins are fungal-specific subunits of Mediator, a large multi-subunit eukaryotic transcriptional co-activator complex. This amplification results in a large pool of ‘free,’ non-Mediator associated, Tlo protein present in C. albicans, but not in C. dubliniensis or other ascomycetes with attenuated virulence. We show that engineering a large ‘free’ pool of the C. dubliniensis Tlo2 (CdTlo2) protein in C. dubliniensis, through overexpression, results in a number of filamentation phenotypes typically associated only with C. albicans. The amplitude of these phenotypes is proportional to the amount of overexpressed CdTlo2 protein. Overexpression of other C. dubliniensis and C. albicans Tlo proteins do result in these phenotypes. Tlo proteins and their orthologs contain a Mediator interaction domain, and a potent transcriptional activation domain. Nuclear localization of the CdTlo2 activation domain, facilitated naturally by the Tlo Mediator binding domain or artificially through an appended nuclear localization signal, is sufficient for the CdTlo2 overexpression phenotypes. A C. albicans med3 null mutant causes multiple defects including the inability to localize Tlo proteins to the nucleus and reduced virulence in a murine systemic infection model. Our data supports a model in which the

Amplification of TLO Mediator Subunit Genes Facilitate Filamentous Growth in Candida Spp.

Directory of Open Access Journals (Sweden)

Zhongle Liu

2016-10-01

Full Text Available Filamentous growth is a hallmark of C. albicans pathogenicity compared to less-virulent ascomycetes. A multitude of transcription factors regulate filamentous growth in response to specific environmental cues. Our work, however, suggests the evolutionary history of C. albicans that resulted in its filamentous growth plasticity may be tied to a change in the general transcription machinery rather than transcription factors and their specific targets. A key genomic difference between C. albicans and its less-virulent relatives, including its closest relative C. dubliniensis, is the unique expansion of the TLO (TeLOmere-associated gene family in C. albicans. Individual Tlo proteins are fungal-specific subunits of Mediator, a large multi-subunit eukaryotic transcriptional co-activator complex. This amplification results in a large pool of 'free,' non-Mediator associated, Tlo protein present in C. albicans, but not in C. dubliniensis or other ascomycetes with attenuated virulence. We show that engineering a large 'free' pool of the C. dubliniensis Tlo2 (CdTlo2 protein in C. dubliniensis, through overexpression, results in a number of filamentation phenotypes typically associated only with C. albicans. The amplitude of these phenotypes is proportional to the amount of overexpressed CdTlo2 protein. Overexpression of other C. dubliniensis and C. albicans Tlo proteins do result in these phenotypes. Tlo proteins and their orthologs contain a Mediator interaction domain, and a potent transcriptional activation domain. Nuclear localization of the CdTlo2 activation domain, facilitated naturally by the Tlo Mediator binding domain or artificially through an appended nuclear localization signal, is sufficient for the CdTlo2 overexpression phenotypes. A C. albicans med3 null mutant causes multiple defects including the inability to localize Tlo proteins to the nucleus and reduced virulence in a murine systemic infection model. Our data supports a model in which

Sphingosine-1-phosphate mediates epidermal growth factor-induced muscle satellite cell activation

Energy Technology Data Exchange (ETDEWEB)

Nagata, Yosuke, E-mail: cynagata@mail.ecc.u-tokyo.ac.jp; Ohashi, Kazuya; Wada, Eiji; Yuasa, Yuki; Shiozuka, Masataka; Nonomura, Yoshiaki; Matsuda, Ryoichi

2014-08-01

Skeletal muscle can regenerate repeatedly due to the presence of resident stem cells, called satellite cells. Because satellite cells are usually quiescent, they must be activated before participating in muscle regeneration in response to stimuli such as injury, overloading, and stretch. Although satellite cell activation is a crucial step in muscle regeneration, little is known of the molecular mechanisms controlling this process. Recent work showed that the bioactive lipid sphingosine-1-phosphate (S1P) plays crucial roles in the activation, proliferation, and differentiation of muscle satellite cells. We investigated the role of growth factors in S1P-mediated satellite cell activation. We found that epidermal growth factor (EGF) in combination with insulin induced proliferation of quiescent undifferentiated mouse myoblast C2C12 cells, which are also known as reserve cells, in serum-free conditions. Sphingosine kinase activity increased when reserve cells were stimulated with EGF. Treatment of reserve cells with the D-erythro-N,N-dimethylsphingosine, Sphingosine Kinase Inhibitor, or siRNA duplexes specific for sphingosine kinase 1, suppressed EGF-induced C2C12 activation. We also present the evidence showing the S1P receptor S1P2 is involved in EGF-induced reserve cell activation. Moreover, we demonstrated a combination of insulin and EGF promoted activation of satellite cells on single myofibers in a manner dependent on SPHK and S1P2. Taken together, our observations show that EGF-induced satellite cell activation is mediated by S1P and its receptor. - Highlights: • EGF in combination with insulin induces proliferation of quiescent C2C12 cells. • Sphingosine kinase activity increases when reserve cells are stimulated with EGF. • EGF-induced activation of reserve cells is dependent on sphingosine kinase and ERK. • The S1P receptor S1P2 is involved in EGF-induced reserve cell activation. • EGF-induced reserve cell activation is mediated by S1P and its

Sphingosine-1-phosphate mediates epidermal growth factor-induced muscle satellite cell activation

International Nuclear Information System (INIS)

Nagata, Yosuke; Ohashi, Kazuya; Wada, Eiji; Yuasa, Yuki; Shiozuka, Masataka; Nonomura, Yoshiaki; Matsuda, Ryoichi

2014-01-01

Skeletal muscle can regenerate repeatedly due to the presence of resident stem cells, called satellite cells. Because satellite cells are usually quiescent, they must be activated before participating in muscle regeneration in response to stimuli such as injury, overloading, and stretch. Although satellite cell activation is a crucial step in muscle regeneration, little is known of the molecular mechanisms controlling this process. Recent work showed that the bioactive lipid sphingosine-1-phosphate (S1P) plays crucial roles in the activation, proliferation, and differentiation of muscle satellite cells. We investigated the role of growth factors in S1P-mediated satellite cell activation. We found that epidermal growth factor (EGF) in combination with insulin induced proliferation of quiescent undifferentiated mouse myoblast C2C12 cells, which are also known as reserve cells, in serum-free conditions. Sphingosine kinase activity increased when reserve cells were stimulated with EGF. Treatment of reserve cells with the D-erythro-N,N-dimethylsphingosine, Sphingosine Kinase Inhibitor, or siRNA duplexes specific for sphingosine kinase 1, suppressed EGF-induced C2C12 activation. We also present the evidence showing the S1P receptor S1P2 is involved in EGF-induced reserve cell activation. Moreover, we demonstrated a combination of insulin and EGF promoted activation of satellite cells on single myofibers in a manner dependent on SPHK and S1P2. Taken together, our observations show that EGF-induced satellite cell activation is mediated by S1P and its receptor. - Highlights: • EGF in combination with insulin induces proliferation of quiescent C2C12 cells. • Sphingosine kinase activity increases when reserve cells are stimulated with EGF. • EGF-induced activation of reserve cells is dependent on sphingosine kinase and ERK. • The S1P receptor S1P2 is involved in EGF-induced reserve cell activation. • EGF-induced reserve cell activation is mediated by S1P and its

Does query expansion limit our learning? A comparison of social-based expansion to content-based expansion for medical queries on the internet.

Science.gov (United States)

Pentoney, Christopher; Harwell, Jeff; Leroy, Gondy

2014-01-01

Searching for medical information online is a common activity. While it has been shown that forming good queries is difficult, Google's query suggestion tool, a type of query expansion, aims to facilitate query formation. However, it is unknown how this expansion, which is based on what others searched for, affects the information gathering of the online community. To measure the impact of social-based query expansion, this study compared it with content-based expansion, i.e., what is really in the text. We used 138,906 medical queries from the AOL User Session Collection and expanded them using Google's Autocomplete method (social-based) and the content of the Google Web Corpus (content-based). We evaluated the specificity and ambiguity of the expansion terms for trigram queries. We also looked at the impact on the actual results using domain diversity and expansion edit distance. Results showed that the social-based method provided more precise expansion terms as well as terms that were less ambiguous. Expanded queries do not differ significantly in diversity when expanded using the social-based method (6.72 different domains returned in the first ten results, on average) vs. content-based method (6.73 different domains, on average).

Giant thermal expansion and α-precipitation pathways in Ti-alloys.

Science.gov (United States)

Bönisch, Matthias; Panigrahi, Ajit; Stoica, Mihai; Calin, Mariana; Ahrens, Eike; Zehetbauer, Michael; Skrotzki, Werner; Eckert, Jürgen

2017-11-10

Ti-alloys represent the principal structural materials in both aerospace development and metallic biomaterials. Key to optimizing their mechanical and functional behaviour is in-depth know-how of their phases and the complex interplay of diffusive vs. displacive phase transformations to permit the tailoring of intricate microstructures across a wide spectrum of configurations. Here, we report on structural changes and phase transformations of Ti-Nb alloys during heating by in situ synchrotron diffraction. These materials exhibit anisotropic thermal expansion yielding some of the largest linear expansion coefficients (+ 163.9×10 -6 to -95.1×10 -6  °C -1 ) ever reported. Moreover, we describe two pathways leading to the precipitation of the α-phase mediated by diffusion-based orthorhombic structures, α″ lean and α″ iso . Via coupling the lattice parameters to composition both phases evolve into α through rejection of Nb. These findings have the potential to promote new microstructural design approaches for Ti-Nb alloys and β-stabilized Ti-alloys in general.

Effects of ejector geometries on performance of ejector-expansion R410A air conditioner considering cooling seasonal performance factor

International Nuclear Information System (INIS)

Jeon, Yongseok; Jung, Jongho; Kim, Dongwoo; Kim, Sunjae; Kim, Yongchan

2017-01-01

Highlights: •The performance of an ejector-expansion R410A air conditioner is measured. •The effect of ejector geometries on the COP and CSPF is analyzed. •The mixing-section diameter of the ejector is optimized based on the CSPF. •The mixing-section diameter is optimized based on the climatic conditions. -- Abstract: The objective of this study was to investigate the effects of ejector geometries on the performance of an ejector-expansion air conditioner (EEAC) considering the cooling seasonal performance factor (CSPF). The performance of the EEAC using R410A was measured and analyzed by varying the compressor speed, outdoor-bin temperature, operating pressures, nozzle-throat diameter, and mixing-section diameter. The EEAC in the medium-capacity mode exhibited maximum coefficient of performance (COP) improvement, i.e., 7.5%, over the baseline (conventional) cycle. The optimum mixing-section diameter was determined to be 9 mm based on the CSPF. In addition, the optimum mixing-section diameter increased with an increase in the annual average outdoor temperature. The CSPF of the EEAC with the optimized mixing-section diameter improved in the range of 16.0–20.3% over the baseline cycle depending on the climatic conditions.

Light-induced lattice expansion leads to high-efficiency perovskite solar cells

Science.gov (United States)

Tsai, Hsinhan; Asadpour, Reza; Blancon, Jean-Christophe; Stoumpos, Constantinos C.; Durand, Olivier; Strzalka, Joseph W.; Chen, Bo; Verduzco, Rafael; Ajayan, Pulickel M.; Tretiak, Sergei; Even, Jacky; Alam, Muhammad Ashraf; Kanatzidis, Mercouri G.; Nie, Wanyi; Mohite, Aditya D.

2018-04-01

Light-induced structural dynamics plays a vital role in the physical properties, device performance, and stability of hybrid perovskite–based optoelectronic devices. We report that continuous light illumination leads to a uniform lattice expansion in hybrid perovskite thin films, which is critical for obtaining high-efficiency photovoltaic devices. Correlated, in situ structural and device characterizations reveal that light-induced lattice expansion benefits the performances of a mixed-cation pure-halide planar device, boosting the power conversion efficiency from 18.5 to 20.5%. The lattice expansion leads to the relaxation of local lattice strain, which lowers the energetic barriers at the perovskite-contact interfaces, thus improving the open circuit voltage and fill factor. The light-induced lattice expansion did not compromise the stability of these high-efficiency photovoltaic devices under continuous operation at full-spectrum 1-sun (100 milliwatts per square centimeter) illumination for more than 1500 hours.

Modulated Hermite series expansions and the time-bandwidth product

NARCIS (Netherlands)

Brinker, den A.C.; Sarroukh, B.E.

2000-01-01

The harmonically modulated Hermite series constitute an orthonormal basis in the Hilbert space of square-integrable functions. This basis comprises three free parameters, namely a translation, a modulation, and a scale factor. In practical situations, we are interested in series expansions that are

Expansion of microvascular networks in vivo by phthalimide neovascular factor 1 (PNF1).

Science.gov (United States)

Wieghaus, Kristen A; Nickerson, Meghan M; Petrie Aronin, Caren E; Sefcik, Lauren S; Price, Richard J; Paige, Mikell A; Brown, Milton L; Botchwey, Edward A

2008-12-01

Phthalimide neovascular factor (PNF1, formerly SC-3-149) is a potent stimulator of proangiogenic signaling pathways in endothelial cells. In this study, we evaluated the in vivo effects of sustained PNF1 release to promote ingrowth and expansion of microvascular networks surrounding biomaterial implants. The dorsal skinfold window chamber was used to evaluate the structural remodeling response of the local microvasculature. PNF1 was released from poly(lactic-co-glycolic acid) (PLAGA) films, and a transport model was utilized to predict PNF1 penetration into the surrounding tissue. PNF1 significantly expanded microvascular networks within a 2mm radius from implants after 3 and 7 days by increasing microvessel length density and lumenal diameter of local arterioles and venules. Staining of histological sections with CD11b showed enhanced recruitment of circulating white blood cells, including monocytes, which are critical for the process of vessel enlargement through arteriogenesis. As PNF1 has been shown to modulate MT1-MMP, a facilitator of CCL2 dependent leukocyte transmigration, aspects of window chamber experiments were repeated in CCR2(-/-) (CCL2 receptor) mouse chimeras to more fully explore the critical nature of monocyte recruitment on the therapeutic benefits of PNF1 function in vivo.

MEDIATOR18 and MEDIATOR20 confer susceptibility to Fusarium oxysporum in Arabidopsis thaliana

Science.gov (United States)

Stiller, Jiri; Davoine, Celine; Björklund, Stefan; Manners, John M.; Kazan, Kemal; Schenk, Peer M.

2017-01-01

The conserved protein complex known as Mediator conveys transcriptional signals by acting as an intermediary between transcription factors and RNA polymerase II. As a result, Mediator subunits play multiple roles in regulating developmental as well as abiotic and biotic stress pathways. In this report we identify the head domain subunits MEDIATOR18 and MEDIATOR20 as important susceptibility factors for Fusarium oxysporum infection in Arabidopsis thaliana. Mutants of MED18 and MED20 display down-regulation of genes associated with jasmonate signaling and biosynthesis while up-regulation of salicylic acid associated pathogenesis related genes and reactive oxygen producing and scavenging genes. We propose that MED18 and MED20 form a sub-domain within Mediator that controls the balance of salicylic acid and jasmonate associated defense pathways. PMID:28441405

Vascular endothelial growth factor signaling is necessary for expansion of medullary microvessels during postnatal kidney development

DEFF Research Database (Denmark)

Robdrup Tinning, Anne; Jensen, Boye L; Johnsen, Iben

2016-01-01

Postnatal inhibition or deletion of angiotensin II (ANG II) AT1 receptors impairs renal medullary mircrovascular development through a mechanism that may include vascular endothelial growth factor (VEGF). The present study was designed to test if VEGF/VEGF receptor signaling is necessary....... In human fetal kidney tissue, immature vascular bundles appeared early in the third trimester (GA27-28) and expanded in size until term. Rat pups treated with the VEGF receptor-2 (VEGFR2) inhibitor vandetanib (100 mg·kg(-1)·day(-1)) from P7 to P12 or P10 to P16 displayed growth retardation and proteinuria...... for the development of the renal medullary microcirculation. Endothelial cell-specific immunolabeling of kidney sections from rats showed immature vascular bundles at postnatal day (P) 10 with subsequent expansion of bundles until P21. Medullary VEGF protein abundance coincided with vasa recta bundle formation...

Th17 cell-mediated immune responses promote mast cell proliferation by triggering stem cell factor in keratinocytes

International Nuclear Information System (INIS)

Cho, Kyung-Ah; Park, Minhwa; Kim, Yu-Hee; Woo, So-Youn

2017-01-01

Although mast cells are traditionally thought to function as effector cells in allergic responses, they have increasingly been recognized as important regulators of various immune responses. Mast cells mature locally; thus, tissue-specific influences are important for promoting mast cell accumulation and survival in the skin and the gastrointestinal tract. In this study, we determined the effects of keratinocytes on mast cell accumulation during Th17-mediated skin inflammation. We observed increases in dermal mast cells in imiquimod-induced psoriatic dermatitis in mice accompanied by the expression of epidermal stem cell factor (SCF), a critical mast cell growth factor. Similar to mouse epidermal keratinocytes, SCF was highly expressed in the human HaCaT keratinocyte cell line following stimulation with IL−17. Further, keratinocytes promoted mast cell proliferation following stimulation with IL−17 in vitro. However, the effects of keratinocytes on mast cells were significantly diminished in the presence of anti−CD117 (stem cell factor receptor) blocking antibodies. Taken together, our results revealed that the Th17-mediated inflammatory environment promotes mast cell accumulation through keratinocyte-derived SCF. - Highlights: • Psoriasis-like skin inflammation increase dermal mast cells. • Keratinocyte produce stem cell factor in psoriasis-like skin inflammation. • Keratinocyte promote mast cell proliferation by stem cell factor dependent manner

A prospective examination of the path from child abuse and neglect to illicit drug use in middle adulthood: the potential mediating role of four risk factors.

Science.gov (United States)

Wilson, Helen W; Widom, Cathy Spatz

2009-03-01

This study examines prostitution, homelessness, delinquency and crime, and school problems as potential mediators of the relationship between childhood abuse and neglect (CAN) and illicit drug use in middle adulthood. Children with documented cases of physical and sexual abuse and neglect (ages 0-11) during 1967-1971 were matched with non-maltreated children and followed into middle adulthood (approximate age 39). Mediators were assessed in young adulthood (approximate age 29) through in-person interviews between 1989 and 1995 and official arrest records through 1994 (N = 1,196). Drug use was assessed via self-reports of past year use of marijuana, psychedelics, cocaine, and/or heroin during 2000-2002 (N = 896). Latent variable structural equation modeling (SEM) was used to test: (1) a four-factor model with separate pathways from CAN to illicit drug use through each of the mediating risk factors and (2) a second-order model with a single mediating risk factor comprised of prostitution, homelessness, delinquency and crime, and poor school performance. Analyses were performed separately for women and men, controlling for race/ethnicity and early drug use. In the four-factor model for both men and women, CAN was significantly related to each of the mediators, but no paths from the mediators to drug use were significant. For women, the second-order risk factor mediated the relationship between CAN and illicit drug use in middle adulthood. For men, neither child abuse and neglect nor the second-order risk factor predicted drug use in middle adulthood. These results suggest that for women, the path from CAN to middle adulthood drug use is part of a general "problem behavior syndrome" evident earlier in life.

The Role of the Process and Design Variables in Improving the Performance of Heat Exchanger Tube Expansion

Directory of Open Access Journals (Sweden)

Changwan Han

2018-05-01

Full Text Available In the expansion process of a fin-tube heat exchanger, the process variables and shape of the expansion ball affect the deformation of the tube’s inner grooves, the adhesion, and the expansion force. These factors influence the efficiency of heat transfer and the lifetime of the expansion equipment. Therefore, this study analyzed the influential variables of the tube expansion process as well as the expansion ball design through experiments and simulations. A new method was proposed to determine the severity of adhesion in the tube’s inner grooves using the expansion force rate. Expansion experiments with Al tubes show that the expansion force decreases when using a lubricant with high viscosity and when the lubricant remains on the expansion ball for a longer duration. Finite element analysis was also performed to examine the expansion of Cu tubes, which showed that the expansion force was higher when using expansion ball shapes that have higher contact area between the ball and tube surface. The radius of curvature of the expansion ball also influenced the expansion force. However, increasing the ratio of the radial force to the expansion force increased the deformation of the tube’s inner grooves.

Constructing the Suicide Risk Index (SRI): does it work in predicting suicidal behavior in young adults mediated by proximal factors?

Science.gov (United States)

O'Connor, Maebh; Dooley, Barbara; Fitzgerald, Amanda

2015-01-01

Suicide is a key concern among young adults. The aim of the study was to (1) construct a suicide risk index (SRI) based on demographic, situational, and behavioral factors known to be linked to suicidal behavior and (2) investigate whether the association between the SRI and suicidal behavior was mediated by proximal processes (personal factors, coping strategies, and emotional states). Participants consisted of 7,558 individuals aged 17-25 years (M = 20.35, SD = 1.91). Nearly 22% (n = 1,542) reported self-harm and 7% (n = 499) had attempted suicide. Mediation analysis revealed both a direct effect (ß = .299, 95% CI = [.281, .317], p suicidal behavior. The strongest mediators were levels of self-esteem, depression, and avoidant coping. Interventions to increase self-esteem, reduce depression, and encourage adaptive coping strategies may prevent suicidal behavior in young people.

Relict or colonizer? Extinction and range expansion of penguins in southern New Zealand

Science.gov (United States)

Boessenkool, Sanne; Austin, Jeremy J.; Worthy, Trevor H.; Scofield, Paul; Cooper, Alan; Seddon, Philip J.; Waters, Jonathan M.

2008-01-01

Recent human expansion into the Pacific initiated a dramatic avian extinction crisis, and surviving taxa are typically interpreted as declining remnants of previously abundant populations. As a case in point, New Zealand's endangered yellow-eyed penguin (Megadyptes antipodes) is widely considered to have been more abundant and widespread in the past. By contrast, our genetic and morphological analyses of prehistoric, historic and modern penguin samples reveal that this species expanded its range to the New Zealand mainland only in the last few hundred years. This range expansion was apparently facilitated by the extinction of M. antipodes' previously unrecognized sister species following Polynesian settlement in New Zealand. Based on combined genetic and morphological data, we describe this new penguin species, the first known to have suffered human-mediated extinction. The range expansion of M. antipodes so soon after the extinction of its sister species supports a historic paradigmatic shift in New Zealand Polynesian culture. Additionally, such a dynamic biological response to human predation reveals a surprising and less recognized potential for species to have benefited from the extinction of their ecologically similar sister taxa and highlights the complexity of large-scale extinction events. PMID:19019791

Pathogen-free, plasma-poor platelet lysate and expansion of human mesenchymal stem cells.

Science.gov (United States)

Iudicone, Paola; Fioravanti, Daniela; Bonanno, Giuseppina; Miceli, Michelina; Lavorino, Claudio; Totta, Pierangela; Frati, Luigi; Nuti, Marianna; Pierelli, Luca

2014-01-27

Supplements to support clinical-grade cultures of mesenchymal stem cells (MSC) are required to promote growth and expansion of these cells. Platelet lysate (PL) is a human blood component which may replace animal serum in MSC cultures being rich in various growth factors. Here, we describe a plasma poor pathogen-free platelet lysate obtained by pooling 12 platelet (PLT) units, to produce a standardized and safe supplement for clinical-grade expansion of MSC. PL lots were obtained by combining 2 6-unit PLT pools in additive solution (AS) following a transfusional-based procedure including pathogen inactivation (PI) by Intercept technology and 3 cycles of freezing/thawing, followed by membrane removal. Three PI-PL and 3 control PL lots were produced to compare their ability to sustain bone marrow derived MSC selection and expansion. Moreover, two further PL, subjected to PI or not, were also produced starting from the same initial PLT pools to evaluate the impact of PI on growth factor concentration and capacity to sustain cell growth. Additional PI-PL lots were used for comparison with fetal bovine serum (FBS) on MSC expansion. Immunoregulatory properties of PI-PL-generated MSC were documented in vitro by mixed lymphocyte culture (MLC) and peripheral blood mononuclear cells (PBMC) mitogen induced proliferation. PI-PL and PL control lots had similar concentrations of 4 well-described growth factors endowed with MSC stimulating ability. Initial growth and MSC expansion by PI-PL and PL controls were comparable either using different MSC populations or in head to head experiments. Moreover, PI-PL and PL control sustained similar MSC growth of frozen/thawed MSC. Multilineage differentiation of PI-derived and PI-PL-derived MSC were maintained in any MSC cultures as well as their immunoregulatory properties. Finally, no direct impact of PI on growth factor concentration and MSC growth support was observed, whereas the capacity of FBS to sustain MSC expansion in basic

Impact of Patient-centered eHealth Applications on Patient Outcomes: A Review on the Mediating Influence of Human Factor Issues.

Science.gov (United States)

Wildenbos, G A; Peute, L W; Jaspers, M W M

2016-11-10

To examine the evidence of the impact of patient- centered eHealth applications on patient care and to analyze if and how reported human factor issues mediated the outcomes. We searched PubMed (2014-2015) for studies evaluating the impact of patient-centered eHealth applications on patient care (behavior change, self-efficacy, and patient health-related outcomes). The Systems Engineering Initiative for Patient Safety (SEIPS 2.0) model was used as a guidance framework to identify the reported human factors possibly impacting the effectiveness of an eHealth intervention. Of the 348 potentially relevant papers, 10 papers were included for data analysis. None of the 10 papers reported a negative impact of the eHealth intervention. Seven papers involved a randomized controlled trial (RCT) study. Six of these RCTs reported a positive impact of the eHealth intervention on patient care. All 10 papers reported on human factor issues possibly mediating effects of patient-centered eHealth. Human factors involved patient characteristics, perceived social support, and (type of) interaction between patient and provider. While the amount of patient-centered eHealth interventions increases, many questions remain as to whether and to what extent human factors mediate their use and impact. Future research should adopt a formal theory-driven approach towards human factors when investigating those factors' influence on the effectiveness of these interventions. Insights could then be used to better tailor the content and design of eHealth solutions according to patient user profiles, so as to enhance eHealth interventions impact on patient behavior, self-efficacy, and health-related outcomes.

JASPAR 2016: a major expansion and update of the open-access database of transcription factor binding profiles.

Science.gov (United States)

Mathelier, Anthony; Fornes, Oriol; Arenillas, David J; Chen, Chih-Yu; Denay, Grégoire; Lee, Jessica; Shi, Wenqiang; Shyr, Casper; Tan, Ge; Worsley-Hunt, Rebecca; Zhang, Allen W; Parcy, François; Lenhard, Boris; Sandelin, Albin; Wasserman, Wyeth W

2016-01-04

JASPAR (http://jaspar.genereg.net) is an open-access database storing curated, non-redundant transcription factor (TF) binding profiles representing transcription factor binding preferences as position frequency matrices for multiple species in six taxonomic groups. For this 2016 release, we expanded the JASPAR CORE collection with 494 new TF binding profiles (315 in vertebrates, 11 in nematodes, 3 in insects, 1 in fungi and 164 in plants) and updated 59 profiles (58 in vertebrates and 1 in fungi). The introduced profiles represent an 83% expansion and 10% update when compared to the previous release. We updated the structural annotation of the TF DNA binding domains (DBDs) following a published hierarchical structural classification. In addition, we introduced 130 transcription factor flexible models trained on ChIP-seq data for vertebrates, which capture dinucleotide dependencies within TF binding sites. This new JASPAR release is accompanied by a new web tool to infer JASPAR TF binding profiles recognized by a given TF protein sequence. Moreover, we provide the users with a Ruby module complementing the JASPAR API to ease programmatic access and use of the JASPAR collection of profiles. Finally, we provide the JASPAR2016 R/Bioconductor data package with the data of this release. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Numerical Investigation of magnetohydrodynamic flow through Sudden expansion pipes in Liquid Metal Blankets

Energy Technology Data Exchange (ETDEWEB)

Feng, Jingchao; He, Qingyun; Chen, Hongli, E-mail: hlchen1@ustc.edu.cn; Ye, Minyou

2016-11-01

In fusion liquid metal blanket, sudden expansions and sudden contractions are very common geometries. Changing of the cross-section causes 3-D magnetohydrodynamic (MHD) effects, which will affect the flow pattern, current distribution and pressure drop. In this paper the numerical code based on OpenFOAM platform developed by University of Science and Technology of China was used to investigate and optimize the sudden expansion pipe. The code has been validated by the recommended benchmark cases including Shercliff, Hunt, ALEX experiments (rectangular duct and round pipe) and KIT experiment cases. The obtained numerical results agreed well with those of all the benchmark cases. Previous and valuable analytical and experimental works have been done by L. Buhler, et. el. Based on these works, in the present paper, further investigation of different expansion lengths between the upstream pipe and downstream pipe at high Hartmann number and Reynolds number were conducted. Besides, different expansion ratios with a specific expansion length were conducted. The numerical results showed that with the increasing of expansion length, the 3D MHD effects gradually weakened. Especially, the 3D pressure drop decreases with the increasing of expansion length. Whereas, the expansion ratio factor shows no obvious influences on the total MHD pressure drop but greatly influence the local pressure distribution. These numerical simulations can be used to evaluate the MHD flow inside the expansion and contraction pipes.

Adipokines and the cardiovascular system: mechanisms mediating health and disease.

Science.gov (United States)

Northcott, Josette M; Yeganeh, Azadeh; Taylor, Carla G; Zahradka, Peter; Wigle, Jeffrey T

2012-08-01

This review focuses on the role of adipokines in the maintenance of a healthy cardiovascular system, and the mechanisms by which these factors mediate the development of cardiovascular disease in obesity. Adipocytes are the major cell type comprising the adipose tissue. These cells secrete numerous factors, termed adipokines, into the blood, including adiponectin, leptin, resistin, chemerin, omentin, vaspin, and visfatin. Adipose tissue is a highly vascularised endocrine organ, and different adipose depots have distinct adipokine secretion profiles, which are altered with obesity. The ability of many adipokines to stimulate angiogenesis is crucial for adipose tissue expansion; however, excessive blood vessel growth is deleterious. As well, some adipokines induce inflammation, which promotes cardiovascular disease progression. We discuss how these 7 aforementioned adipokines act upon the various cardiovascular cell types (endothelial progenitor cells, endothelial cells, vascular smooth muscle cells, pericytes, cardiomyocytes, and cardiac fibroblasts), the direct effects of these actions, and their overall impact on the cardiovascular system. These were chosen, as these adipokines are secreted predominantly from adipocytes and have known effects on cardiovascular cells.

Student understanding of Taylor series expansions in statistical mechanics

Directory of Open Access Journals (Sweden)

Trevor I. Smith

2013-08-01

Full Text Available One goal of physics instruction is to have students learn to make physical meaning of specific mathematical expressions, concepts, and procedures in different physical settings. As part of research investigating student learning in statistical physics, we are developing curriculum materials that guide students through a derivation of the Boltzmann factor using a Taylor series expansion of entropy. Using results from written surveys, classroom observations, and both individual think-aloud and teaching interviews, we present evidence that many students can recognize and interpret series expansions, but they often lack fluency in creating and using a Taylor series appropriately, despite previous exposures in both calculus and physics courses.

Student understanding of Taylor series expansions in statistical mechanics

Science.gov (United States)

Smith, Trevor I.; Thompson, John R.; Mountcastle, Donald B.

2013-12-01

One goal of physics instruction is to have students learn to make physical meaning of specific mathematical expressions, concepts, and procedures in different physical settings. As part of research investigating student learning in statistical physics, we are developing curriculum materials that guide students through a derivation of the Boltzmann factor using a Taylor series expansion of entropy. Using results from written surveys, classroom observations, and both individual think-aloud and teaching interviews, we present evidence that many students can recognize and interpret series expansions, but they often lack fluency in creating and using a Taylor series appropriately, despite previous exposures in both calculus and physics courses.

Shape, size and temperature dependency of thermal expansion ...

Indian Academy of Sciences (India)

M GOYAL

2018-05-19

May 19, 2018 ... Oriental J. Chem.32(4), 2193 (2016), is extended in the present study using Qi and Wang model [Mater. Chem. Phys. ... Nanomaterials; shape factor; size effect; thermal expansion; equation of state. ... als are different from that of their bulk material. ..... and 1c along with the present calculated results. It is.

Electrochemical detection of DNA triplet repeat expansion

Czech Academy of Sciences Publication Activity Database

Fojta, Miroslav; Havran, Luděk; Vojtíšková, Marie; Paleček, Emil

2004-01-01

Roč. 126, č. 21 (2004), s. 6532-6533 ISSN 0002-7863 R&D Projects: GA AV ČR IAA4004402; GA AV ČR IBS5004355; GA AV ČR KJB4004302; GA AV ČR KSK4055109 Institutional research plan: CEZ:AV0Z5004920 Keywords : DNA triplet repeat expansion * PCR amplification * neurodegenerative diseases Subject RIV: BO - Biophysics Impact factor: 6.903, year: 2004

Tanshinon IIA injection accelerates tissue expansion by reducing the formation of the fibrous capsule.

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Yu, Qingxiong; Sheng, Lingling; Yang, Mei; Zhu, Ming; Huang, Xiaolu; Li, Qingfeng

2014-01-01

The tissue expansion technique has been applied to obtain new skin tissue to repair large defects in clinical practice. The implantation of tissue expander could initiate a host response to foreign body (FBR), which leads to fibrotic encapsulation around the expander and prolongs the period of tissue expansion. Tanshinon IIA (Tan IIA) has been shown to have anti-inflammation and immunoregulation effect. The rat tissue expansion model was used in this study to observe whether Tan IIA injection systematically could inhibit the FBR to reduce fibrous capsule formation and accelerate the process of tissue expansion. Forty-eight rats were randomly divided into the Tan IIA group and control group with 24 rats in each group. The expansion was conducted twice a week to maintain a capsule pressure of 60 mmHg. The expansion volume and expanded area were measured. The expanded tissue in the two groups was harvested, and histological staining was performed; proinflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) and transforming growth factor-β (TGF-β) were examined. The expansion volume and the expanded area in the Tan IIA group were greater than that of the control group. The thickness of the fibrous capsule in the Tan IIA group was reduced with no influence on the normal skin regeneration. Decreased infiltration of macrophages, lower level of TNF-α, IL-6, IL-1β and TGF-β, less proliferating myofibroblasts and enhanced neovascularization were observed in the Tan IIA group. Our findings indicated that the Tan IIA injection reduced the formation of the fibrous capsule and accelerated the process of tissue expansion by inhibiting the FBR.

Tanshinon IIA injection accelerates tissue expansion by reducing the formation of the fibrous capsule.

Directory of Open Access Journals (Sweden)

Qingxiong Yu

Full Text Available The tissue expansion technique has been applied to obtain new skin tissue to repair large defects in clinical practice. The implantation of tissue expander could initiate a host response to foreign body (FBR, which leads to fibrotic encapsulation around the expander and prolongs the period of tissue expansion. Tanshinon IIA (Tan IIA has been shown to have anti-inflammation and immunoregulation effect. The rat tissue expansion model was used in this study to observe whether Tan IIA injection systematically could inhibit the FBR to reduce fibrous capsule formation and accelerate the process of tissue expansion. Forty-eight rats were randomly divided into the Tan IIA group and control group with 24 rats in each group. The expansion was conducted twice a week to maintain a capsule pressure of 60 mmHg. The expansion volume and expanded area were measured. The expanded tissue in the two groups was harvested, and histological staining was performed; proinflammatory cytokines such as tumor necrosis factor-α (TNF-α, interleukin-6 (IL-6 and interleukin-1β (IL-1β and transforming growth factor-β (TGF-β were examined. The expansion volume and the expanded area in the Tan IIA group were greater than that of the control group. The thickness of the fibrous capsule in the Tan IIA group was reduced with no influence on the normal skin regeneration. Decreased infiltration of macrophages, lower level of TNF-α, IL-6, IL-1β and TGF-β, less proliferating myofibroblasts and enhanced neovascularization were observed in the Tan IIA group. Our findings indicated that the Tan IIA injection reduced the formation of the fibrous capsule and accelerated the process of tissue expansion by inhibiting the FBR.

Unilateral re-expansion pulmonary oedema treated with C-PAP

Directory of Open Access Journals (Sweden)

Giovanni Volpicelli

2009-06-01

Full Text Available Unilateral re-expansion pulmonary oedema is a rare but dangerous complication of treatment for pulmonary atelectasis, pleural effusion and pneumothorax, whose pathogenesis is not completely known. The clinical picture varies considerably from asymptomatic forms with positive radiographic findings to forms with severe respiratory insufficiency and haemodynamic instability. Little data is available in literature on the treatment of re-expansion pulmonary oedema with non-invasive continuous positive airway pressure ventilation. In this article, we describe the case of a 75 year-old man who reported to our Emergency Department with extensive spontaneous left pneumothorax. Following placement of the transthoracic drain, the patient presented a clinical picture of severe respiratory insufficiency with circulatory collapse caused by unilateral re-expansion pulmonary oedema. The case was successfully treated with the application of non-invasive continuous positive airway pressure ventilation. The article briefly discusses current knowledge with regard to the aetiological and pathogenetic factors of this complication of emergency pneumothorax treatment.

Epidermal growth factor induction of front–rear polarity and migration in keratinocytes is mediated by integrin-linked kinase and ELMO2

Science.gov (United States)

Ho, Ernest; Dagnino, Lina

2012-01-01

Epidermal growth factor (EGF) is a potent chemotactic and mitogenic factor for epidermal keratinocytes, and these properties are central for normal epidermal regeneration after injury. The involvement of mitogen-activated protein kinases as mediators of the proliferative effects of EGF is well established. However, the molecular mechanisms that mediate motogenic responses to this growth factor are not clearly understood. An obligatory step for forward cell migration is the development of front–rear polarity and formation of lamellipodia at the leading edge. We show that stimulation of epidermal keratinocytes with EGF, but not with other growth factors, induces development of front–rear polarity and directional migration through a pathway that requires integrin-linked kinase (ILK), Engulfment and Cell Motility-2 (ELMO2), integrin β1, and Rac1. Furthermore, EGF induction of front–rear polarity and chemotaxis require the tyrosine kinase activity of the EGF receptor and are mediated by complexes containing active RhoG, ELMO2, and ILK. Our findings reveal a novel link between EGF receptor stimulation, ILK-containing complexes, and activation of small Rho GTPases necessary for acquisition of front–rear polarity and forward movement. PMID:22160594

Epidermal growth factor induction of front-rear polarity and migration in keratinocytes is mediated by integrin-linked kinase and ELMO2.

Science.gov (United States)

Ho, Ernest; Dagnino, Lina

2012-02-01

Epidermal growth factor (EGF) is a potent chemotactic and mitogenic factor for epidermal keratinocytes, and these properties are central for normal epidermal regeneration after injury. The involvement of mitogen-activated protein kinases as mediators of the proliferative effects of EGF is well established. However, the molecular mechanisms that mediate motogenic responses to this growth factor are not clearly understood. An obligatory step for forward cell migration is the development of front-rear polarity and formation of lamellipodia at the leading edge. We show that stimulation of epidermal keratinocytes with EGF, but not with other growth factors, induces development of front-rear polarity and directional migration through a pathway that requires integrin-linked kinase (ILK), Engulfment and Cell Motility-2 (ELMO2), integrin β1, and Rac1. Furthermore, EGF induction of front-rear polarity and chemotaxis require the tyrosine kinase activity of the EGF receptor and are mediated by complexes containing active RhoG, ELMO2, and ILK. Our findings reveal a novel link between EGF receptor stimulation, ILK-containing complexes, and activation of small Rho GTPases necessary for acquisition of front-rear polarity and forward movement.

Activating transcription factor 4 underlies the pathogenesis of arsenic trioxide-mediated impairment of macrophage innate immune functions

Energy Technology Data Exchange (ETDEWEB)

Srivastava, Ritesh K.; Li, Changzhao [Department of Dermatology and Skin Diseases Research Center, University of Alabama at Birmingham, Birmingham, AL (United States); Wang, Yong [Department of Medicine, University of Alabama at Birmingham, Birmingham, AL (United States); Weng, Zhiping; Elmets, Craig A. [Department of Dermatology and Skin Diseases Research Center, University of Alabama at Birmingham, Birmingham, AL (United States); Harrod, Kevin S. [Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, AL (United States); Deshane, Jessy S., E-mail: treena@uab.edu [Department of Medicine, University of Alabama at Birmingham, Birmingham, AL (United States); Athar, Mohammad, E-mail: mathar@uab.edu [Department of Dermatology and Skin Diseases Research Center, University of Alabama at Birmingham, Birmingham, AL (United States)

2016-10-01

Chronic arsenic exposure to humans is considered immunosuppressive with augmented susceptibility to several infectious diseases. The exact molecular mechanisms, however, remain unknown. Earlier, we showed the involvement of unfolded protein response (UPR) signaling in arsenic-mediated impairment of macrophage functions. Here, we show that activating transcription factor 4 (ATF4), a UPR transcription factor, regulates arsenic trioxide (ATO)-mediated dysregulation of macrophage functions. In ATO-treated ATF4{sup +/+} wild-type mice, a significant down-regulation of CD11b expression was associated with the reduced phagocytic functions of peritoneal and lung macrophages. This severe immuno-toxicity phenotype was not observed in ATO-treated ATF4{sup +/−} heterozygous mice. To confirm these observations, we demonstrated in Raw 264.7 cells that ATF4 knock-down rescues ATO-mediated impairment of macrophage functions including cytokine production, bacterial engulfment and clearance of engulfed bacteria. Sustained activation of ATF4 by ATO in macrophages induces apoptosis, while diminution of ATF4 expression protects against ATO-induced apoptotic cell death. Raw 264.7 cells treated with ATO also manifest dysregulated Ca{sup ++} homeostasis. ATO induces Ca{sup ++}-dependent calpain-1 and caspase-12 expression which together regulated macrophage apoptosis. Additionally, apoptosis was also induced by mitochondria-regulated pathway. Restoring ATO-impaired Ca{sup ++} homeostasis in ER/mitochondria by treatments with the inhibitors of inositol 1,4,5-trisphosphate receptor (IP3R) and voltage-dependent anion channel (VDAC) attenuate innate immune functions of macrophages. These studies identify a novel role for ATF4 in underlying pathogenesis of macrophage dysregulation and immuno-toxicity of arsenic. - Highlights: • ATF4 regulates arsenic-mediated impairment in macrophage functions. • Arsenic-mediated alterations in pulmonary macrophage are diminished in ATF4{sup +/−} mice

Activating transcription factor 4 underlies the pathogenesis of arsenic trioxide-mediated impairment of macrophage innate immune functions

International Nuclear Information System (INIS)

Srivastava, Ritesh K.; Li, Changzhao; Wang, Yong; Weng, Zhiping; Elmets, Craig A.; Harrod, Kevin S.; Deshane, Jessy S.; Athar, Mohammad

2016-01-01

Chronic arsenic exposure to humans is considered immunosuppressive with augmented susceptibility to several infectious diseases. The exact molecular mechanisms, however, remain unknown. Earlier, we showed the involvement of unfolded protein response (UPR) signaling in arsenic-mediated impairment of macrophage functions. Here, we show that activating transcription factor 4 (ATF4), a UPR transcription factor, regulates arsenic trioxide (ATO)-mediated dysregulation of macrophage functions. In ATO-treated ATF4 +/+ wild-type mice, a significant down-regulation of CD11b expression was associated with the reduced phagocytic functions of peritoneal and lung macrophages. This severe immuno-toxicity phenotype was not observed in ATO-treated ATF4 +/− heterozygous mice. To confirm these observations, we demonstrated in Raw 264.7 cells that ATF4 knock-down rescues ATO-mediated impairment of macrophage functions including cytokine production, bacterial engulfment and clearance of engulfed bacteria. Sustained activation of ATF4 by ATO in macrophages induces apoptosis, while diminution of ATF4 expression protects against ATO-induced apoptotic cell death. Raw 264.7 cells treated with ATO also manifest dysregulated Ca ++ homeostasis. ATO induces Ca ++ -dependent calpain-1 and caspase-12 expression which together regulated macrophage apoptosis. Additionally, apoptosis was also induced by mitochondria-regulated pathway. Restoring ATO-impaired Ca ++ homeostasis in ER/mitochondria by treatments with the inhibitors of inositol 1,4,5-trisphosphate receptor (IP3R) and voltage-dependent anion channel (VDAC) attenuate innate immune functions of macrophages. These studies identify a novel role for ATF4 in underlying pathogenesis of macrophage dysregulation and immuno-toxicity of arsenic. - Highlights: • ATF4 regulates arsenic-mediated impairment in macrophage functions. • Arsenic-mediated alterations in pulmonary macrophage are diminished in ATF4 +/− mice. • Changes in macrophage

Individual and family factors associated with self-esteem in young people with epilepsy: A multiple mediation analysis.

Science.gov (United States)

Chew, Judith; Haase, Anne M; Carpenter, John

2017-01-01

As young people experience added demands from living with epilepsy, which may lead to poor psychosocial adjustment, it is essential to examine mechanisms of change to provide practitioners with knowledge to develop effective interventions. The aim of this study was to examine individual and family-level factors - stress and illness perceptions, coping behaviors and family resilience - that promote or maintain young people's self-esteem. From November 2013 to August 2014, young people attending a neurology clinic in KK Women's and Children's Hospital, Singapore, participated in a cross-sectional survey (n=152; 13-16years old). Multiple mediation analyses were conducted to evaluate whether these variables mediated the relationship between illness severity (i.e., low, moderate, high) and self-esteem. Multiple mediation analyses demonstrated that illness severity had a direct effect on young people's self-esteem. Compared to those with moderate illness severity (reference group), young people with low severity had significantly higher self-esteem (c=3.42, pself-esteem through its effects on mediators, such as perceived stress, illness perceptions and family resilience (D 1 : Total ab=3.46, 95% CI 1.13, 5.71; D 2 : Total ab=-2.80, 95% CI -4.35, -1.30). However, young people's coping levels did not predict their self-esteem, when accounting for the effects of other variables. The continued presence of seizure occurrences is likely to place greater demands on young people and their families: in turn, increased stress and negative illness perceptions negatively affected family processes that promote resilience. As the mediating effect of these modifiable factors were above and beyond the contributions of illness characteristics and young people's levels of coping, this has implications for developing individual and family interventions aimed to support young people living with epilepsy. Copyright © 2016 Elsevier Inc. All rights reserved.

Mediated moderation or moderated mediation: relationship between length of unemployment, resilience, coping and health.

Science.gov (United States)

Sojo, Víctor; Guarino, Leticia

2011-05-01

The aim of the present research was to evaluate a model of mediated moderation vs. moderated mediation that could explain the relationship between length of unemployment, dispositional resilience, coping styles and depression and social functioning of Venezuelan unemployed individuals. Self-report measures were administered to a sample of 328 unemployed residents in Caracas, Venezuela. Results indicated that emotional coping acted as a mediator in the relationship between resilience and depression. Individuals with greater resilience used more detachment coping when unemployment was longer, while individuals with poorer resilience in the same situation used less avoidance coping. Resilience acted as a protective moderating factor between longer periods of unemployment and social functioning, a process mediated by detachment coping. Overall, results supported a mediated moderation model, with resilience as the moderating factor and coping as the mediator in the relation between stress due to the length of unemployment and well-being.

Energy expansion planning by considering electrical and thermal expansion simultaneously

International Nuclear Information System (INIS)

Abbasi, Ali Reza; Seifi, Ali Reza

2014-01-01

Highlights: • This paper focused on the expansion planning optimization of energy systems. • Employing two form of energy: the expansion of electrical and thermal energies. • The main objective is to minimize the costs. • A new Modified Honey Bee Mating Optimization (MHBMO) algorithm is applied. - Abstract: This study focused on the expansion planning optimization of energy systems employing two forms of energy: the expansion of electrical and thermal energies simultaneously. The main objective of this investigation is confirming network adequacy by adding new equipment to the network, over a given planning horizon. The main objective of the energy expansion planning (EEP) is to minimize the real energy loss, voltage deviation and the total cost of installation equipments. Since the objectives are different and incommensurable, it is difficult to solve the problem by the conventional approaches that may optimize a single objective. So, the meta-heuristic algorithm is applied to this problem. Here, Honey Bee Mating Optimization algorithm (HBMO) as a new evolutionary optimization algorithm is utilized. In order to improve the total ability of HBMO for the global search and exploration, a new modification process is suggested such a way that the algorithm will search the total search space globally. Also, regarding the uncertainties of the new complicated energy systems, in this paper for the first time, the EEP problem is investigated in a stochastic environment by the use of probabilistic load flow technique based on Point Estimate Method (PEM). In order to evaluate the feasibility and effectiveness of the proposed algorithm, two modified test systems are used as case studies

Instrumental Genesis in Technology-Mediated Learning: From Double Stimulation to Expansive Knowledge Practices

Science.gov (United States)

Ritella, Giuseppe; Hakkarainen, Kai

2012-01-01

The purpose of the present paper is to examine the socio-cultural foundations of technology-mediated collaborative learning. Toward that end, we discuss the role of artifacts in knowledge-creating inquiry, relying on the theoretical ideas of Carl Bereiter, Merlin Donald, Pierre Rabardel, Keith Sawyer and L. S. Vygotsky. We argue that epistemic…

Factors influencing Agrobacterium-mediated embryogenic callus transformation of Valencia sweet orange (Citrus sinensis) containing the pTA29-barnase gene.

Science.gov (United States)

Li, D D; Shi, W; Deng, X X

2003-12-01

Valencia sweet orange (Citrus sinensis (L.) Osbeck) calluses were used as explants to develop a new transformation system for citrus mediated by Agrobacterium tumefaciens. Factors affecting Agrobacterium-mediated transformation efficiency included mode of pre-cultivation, temperature of cocultivation and presence of acetosyringone (AS). The highest transformation efficiency was obtained with a 4-day pre-cultivation period in liquid medium. Transformation efficiency was higher when cocultivation was performed for 3 days at 19 degrees C than at 23 or 28 degrees C. Almost no resistant callus was obtained if the cocultivation medium lacked AS. The transformation procedure yielded transgenic Valencia plants containing the pTA29-barnase gene, as verified by PCR amplification and confirmed by Southern blotting. Because male sterility is a common factor leading to seedlessness in citrus cultivars with parthenocarpic characteristics, production of seedless citrus genotypes by Agrobacterium-mediated genetic transformation is a promising alternative to conventional breeding methods.

UNEARTHING GLOBAL FINANCIAL INCLUSION LEVELS AND ANALYSIS OF FINANCIAL INCLUSION AS A MEDIATING FACTOR IN GLOBAL HUMAN DEVELOPMENT

Directory of Open Access Journals (Sweden)

Roshny Unnikrishnan

2015-04-01

Full Text Available This study is a result of the author’s inquisition to unearth the current values of Global Financial Inclusion and its relationship with economic growth measured by Gross Domestic product(GDP and human development measured by United Nations Human Development Index (HDI. The Financial Inclusion (FI levels are measured using Index for Financial Inclusion .The relationship between GDP and HDI with FI as mediator, using multiple regression, is validated on a global level based on data of 162 countries for the year 2011. An overall global mediation analysis is undertaken to establish Financial Inclusion as a mediating factor and partial mediation on human development is validated. The study is valid and unique in the global context of income inequality prevailing in developed, developing and underdeveloped countries as it validates the argument that an impressive GDP performance does not ensure equity in economic growth.

Expansion joints for LMFBR

International Nuclear Information System (INIS)

Dzenus, M.; Hundhausen, W.; Jansing, W.

1980-01-01

This discourse recounts efforts put into the SNR-2 project; specifically the development of compensation devices. The various prototypes of these compensation devices are described and the state of the development reviewed. Large Na (sodium)-heat transfer systems require a lot of valuable space if the component lay-out does not include compensation devices. So, in order to condense the spatial requirement as much as possible, expansion joints must be integrated into the pipe system. There are two basic types to suit the purpose: axial expansion joints and angular expansion joints. The expansion joints were developed on the basis of specific design criteria whereby differentiation is made between expansion joints of small and large nominal diameter. Expansion joints for installation in the sodium-filled primary piping are equipped with safety bellows in addition to the actual working bellows. Expansion joints must be designed and mounted in a manner to completely withstand seismic forces. The design must exclude any damage to the bellows during intermittent operations, that is, when sodium is drained the bellows' folds must be completely empty; otherwise residual solidified sodium could destroy the bellows when restarting. The expansion joints must be engineered on the basis of the following design data for the secondary system of the SNR project: working pressure: 16 bar; failure mode pressure: 5 events; failure mode: 5 sec., 28.5 bar, 520 deg. C; working temperature: 520 deg. C; temperature transients: 30 deg. C/sec.; service life: 200,000 h; number of load cycles: 10 4 ; material: 1.4948 or 1.4919; layer thickness of folds: 0.5 mm; angular deflection (DN 800): +3 deg. C or; axial expansion absorption (DN 600): ±80 mm; calculation: ASME class. The bellows' development work is not handled within this scope. The bellows are supplied by leading manufacturers, and warrant highest quality. Multiple bellows were selected on the basis of maximum elasticity - a property

Strategies to regulate transcription factor-mediated gene positioning and interchromosomal clustering at the nuclear periphery.

Science.gov (United States)

Randise-Hinchliff, Carlo; Coukos, Robert; Sood, Varun; Sumner, Michael Chas; Zdraljevic, Stefan; Meldi Sholl, Lauren; Garvey Brickner, Donna; Ahmed, Sara; Watchmaker, Lauren; Brickner, Jason H

2016-03-14

In budding yeast, targeting of active genes to the nuclear pore complex (NPC) and interchromosomal clustering is mediated by transcription factor (TF) binding sites in the gene promoters. For example, the binding sites for the TFs Put3, Ste12, and Gcn4 are necessary and sufficient to promote positioning at the nuclear periphery and interchromosomal clustering. However, in all three cases, gene positioning and interchromosomal clustering are regulated. Under uninducing conditions, local recruitment of the Rpd3(L) histone deacetylase by transcriptional repressors blocks Put3 DNA binding. This is a general function of yeast repressors: 16 of 21 repressors blocked Put3-mediated subnuclear positioning; 11 of these required Rpd3. In contrast, Ste12-mediated gene positioning is regulated independently of DNA binding by mitogen-activated protein kinase phosphorylation of the Dig2 inhibitor, and Gcn4-dependent targeting is up-regulated by increasing Gcn4 protein levels. These different regulatory strategies provide either qualitative switch-like control or quantitative control of gene positioning over different time scales. © 2016 Randise-Hinchliff et al.

Expansion joints for LMFBR

Energy Technology Data Exchange (ETDEWEB)

Dzenus, M.; Hundhausen, W.; Jansing, W.

1979-10-15

This discourse recounts efforts put into the SNR-2 project; specifically the development of compensation devices. The various prototypes of these compensation devices are described and the state of development reviewed. The expansion joints were developed on the basis of specific design criteria whereby differentiation is made between expansion joints of small and large nominal diameter. Expansion joints for installation in the sodium-filled primary piping are equipped with safety bellows in addition to the actual working bellows.

Mitochondria mediate tumor necrosis factor-alpha/NF-kappaB signaling in skeletal muscle myotubes

Science.gov (United States)

Li, Y. P.; Atkins, C. M.; Sweatt, J. D.; Reid, M. B.; Hamilton, S. L. (Principal Investigator)

1999-01-01

Tumor necrosis factor-alpha (TNF-alpha) is implicated in muscle atrophy and weakness associated with a variety of chronic diseases. Recently, we reported that TNF-alpha directly induces muscle protein degradation in differentiated skeletal muscle myotubes, where it rapidly activates nuclear factor kappaB (NF-kappaB). We also have found that protein loss induced by TNF-alpha is NF-kappaB dependent. In the present study, we analyzed the signaling pathway by which TNF-alpha activates NF-kappaB in myotubes differentiated from C2C12 and rat primary myoblasts. We found that activation of NF-kappaB by TNF-alpha was blocked by rotenone or amytal, inhibitors of complex I of the mitochondrial respiratory chain. On the other hand, antimycin A, an inhibitor of complex III, enhanced TNF-alpha activation of NK-kappaB. These results suggest a key role of mitochondria-derived reactive oxygen species (ROS) in mediating NF-kappaB activation in muscle. In addition, we found that TNF-alpha stimulated protein kinase C (PKC) activity. However, other signal transduction mediators including ceramide, Ca2+, phospholipase A2 (PLA2), and nitric oxide (NO) do not appear to be involved in the activation of NF-kappaB.

Novel male-biased expression in paralogs of the aphid slimfast nutrient amino acid transporter expansion

Directory of Open Access Journals (Sweden)

Nathanson Lubov

2011-09-01

Full Text Available Abstract Background A major goal of molecular evolutionary biology is to understand the fate and consequences of duplicated genes. In this context, aphids are intriguing because the newly sequenced pea aphid genome harbors an extraordinary number of lineage-specific gene duplications relative to other insect genomes. Though many of their duplicated genes may be involved in their complex life cycle, duplications in nutrient amino acid transporters appear to be associated rather with their essential amino acid poor diet and the intracellular symbiosis aphids rely on to compensate for dietary deficits. Past work has shown that some duplicated amino acid transporters are highly expressed in the specialized cells housing the symbionts, including a paralog of an aphid-specific expansion homologous to the Drosophila gene slimfast. Previous data provide evidence that these bacteriocyte-expressed transporters mediate amino acid exchange between aphids and their symbionts. Results We report that some nutrient amino acid transporters show male-biased expression. Male-biased expression characterizes three paralogs in the aphid-specific slimfast expansion, and the male-biased expression is conserved across two aphid species for at least two paralogs. One of the male-biased paralogs has additionally experienced an accelerated rate of non-synonymous substitutions. Conclusions This is the first study to document male-biased slimfast expression. Our data suggest that the male-biased aphid slimfast paralogs diverged from their ancestral function to fill a functional role in males. Furthermore, our results provide evidence that members of the slimfast expansion are maintained in the aphid genome not only for the previously hypothesized role in mediating amino acid exchange between the symbiotic partners, but also for sex-specific roles.

Quasi-Periodic beta-Expansions and Cut Languages

Czech Academy of Sciences Publication Activity Database

Šíma, Jiří; Savický, Petr

2018-01-01

Roč. 720, 11 April (2018), s. 1-23 ISSN 0304-3975 R&D Projects: GA ČR GBP202/12/G061 Institutional support: RVO:67985807 Keywords : beta-expansion * quasi-periodicity * Pisot number * cut language * Chomsky hierarchy Subject RIV: IN - Informatics, Computer Science OBOR OECD: Computer science s, information science , bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 0.698, year: 2016

Quasi-Periodic beta-Expansions and Cut Languages

Czech Academy of Sciences Publication Activity Database

Šíma, Jiří; Savický, Petr

2018-01-01

Roč. 720, 11 April (2018), s. 1-23 ISSN 0304-3975 R&D Projects: GA ČR GBP202/12/G061 Institutional support: RVO:67985807 Keywords : beta-expansion * quasi-periodicity * Pisot number * cut language * Chomsky hierarchy Subject RIV: IN - Informatics, Computer Science OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 0.698, year: 2016

Systematic identification of core transcription factors mediating dysregulated links bridging inflammatory bowel diseases and colorectal cancer.

Directory of Open Access Journals (Sweden)

Yun Xiao

Full Text Available Accumulating evidence shows a tight link between inflammation and cancer. However, comprehensive identification of pivotal transcription factors (i.e., core TFs mediating the dysregulated links remains challenging, mainly due to a lack of samples that can effectively reflect the connections between inflammation and tumorigenesis. Here, we constructed a series of TF-mediated regulatory networks from a large compendium of expression profiling of normal colonic tissues, inflammatory bowel diseases (IBDs and colorectal cancer (CRC, which contains 1201 samples in total, and then proposed a network-based approach to characterize potential links bridging inflammation and cancer. For this purpose, we computed significantly dysregulated relationships between inflammation and their linked cancer networks, and then 24 core TFs with their dysregulated genes were identified. Collectively, our approach provides us with quite important insight into inflammation-associated tumorigenesis in colorectal cancer, which could also be applied to identify functionally dysregulated relationships mediating the links between other different disease phenotypes.

Expansions for Coulomb wave functions

NARCIS (Netherlands)

Boersma, J.

1969-01-01

In this paper we derive a number of expansions for Whittaker functions, regular and irregular Coulomb wave functions. The main result consists of a new expansion for the irregular Coulomb wave functions of orders zero and one in terms of regular Coulomb wave functions. The latter expansions are

Transforming growth factor β-induced expression of chondroitin sulfate proteoglycans is mediated through non-Smad signaling pathways.

Science.gov (United States)

Jahan, Naima; Hannila, Sari S

2015-01-01

The expression of chondroitin sulfate proteoglycans (CSPGs) by reactive astrocytes is a major factor contributing to glial scarring and regenerative failure after spinal cord injury, but the molecular mechanisms underlying CSPG expression remain largely undefined. One contributing factor is transforming growth factor β (TGFβ), which is upregulated after injury and has been shown to induce expression of CSPGs in vitro. TGFβ typically mediates its effects through the Smad2/3 signaling pathway, and it has been suggested that this pathway is responsible for CSPG expression. However, there is evidence that TGFβ can also activate non-Smad signaling pathways. In this study, we report that TGFβ-induced expression of three different CSPGs--neurocan, brevican, and aggrecan--is mediated through non-Smad signaling pathways. We observed significant increases in TGFβ-induced expression of neurocan, brevican, and aggrecan following siRNA knockdown of Smad2 or Smad4, which indicates that Smad signaling is not required for the expression of these CSPGs. In addition, we show that neurocan, aggrecan, and brevican levels are significantly reduced when TGFβ is administered in the presence of either the PI3K inhibitor LY294002 or the mTOR inhibitor rapamycin, but not the MEK1/2 inhibitor U0126. This suggests that TGFβ mediates this effect through non-Smad-dependent activation of the PI3K-Akt-mTOR signaling pathway, and targeting this pathway may therefore be an effective means of reducing CSPG expression in the injured CNS. Copyright © 2014 Elsevier Inc. All rights reserved.

The "Romsas in Motion" Community Intervention: Mediating Effects of Psychosocial Factors on Forward Transition in the Stages of Change in Physical Activity

Science.gov (United States)

Lorentzen, Catherine; Ommundsen, Yngvar; Jenum, Anne Karen; Holme, Ingar

2009-01-01

This study examines whether a community-based physical activity intervention influenced movement in stages of change in physical activity in an adult population, whether any such effect was mediated by psychosocial influences, and whether any such mediations were moderated by sociodemographic or anthropometric factors. The 3-year-long…

Unitary pole approximations and expansions in few-body systems

International Nuclear Information System (INIS)

Casel, A.; Haberzettl, H.; Sandhas, W.

1982-01-01

The unitary pole approximations or expansions of the two-body subsystem operators are well known, and particularly efficient and practical, methods to reduce the three-body problem to an effective two-body theory. In the present investigation we develop generalizations of these approximation techniques to the subsystem amplitudes of problems with higher particle numbers. They are based on the expansion of effective potentials which, in contrast to the genuine two-body interactions, are now energy dependent. Despite this feature our generalizations require only energy independent form factors, thus preserving one of the essential advantages of the genuine two-body approach. The application of these techniques to the four-body case is discussed in detail

Multi-criteria Generation-Expansion Planning with Carbon dioxide emissions and Nuclear Safety considerations

International Nuclear Information System (INIS)

Lee, Hun Gyu; Kim, Young Chang

2010-01-01

A multiple criteria decision making (MCDM) method is developed to aid decision makers in Generation Expansion planning and management. Traditionally, the prime objective of an electric utility's generation-expansion planning has been to determine the minimum cost supply plans that meet expected demands over a planning horizon (typically 10 to 30 years). Today, however, the nature of decision environments has changed substantially. Increased policy attention is given to solve the multiple tradeoff function including environmental and social factors as well as economic one related to nuclear power expansion. In order to deal with this MCDM problem, the Analytic Hierarchy Process (AHP) Model is applied

Telomerase-mediated life-span extension of human primary fibroblasts by human artificial chromosome (HAC) vector

International Nuclear Information System (INIS)

Shitara, Shingo; Kakeda, Minoru; Nagata, Keiko; Hiratsuka, Masaharu; Sano, Akiko; Osawa, Kanako; Okazaki, Akiyo; Katoh, Motonobu; Kazuki, Yasuhiro; Oshimura, Mitsuo; Tomizuka, Kazuma

2008-01-01

Telomerase-mediated life-span extension enables the expansion of normal cells without malignant transformation, and thus has been thought to be useful in cell therapies. Currently, integrating vectors including the retrovirus are used for human telomerase reverse transcriptase (hTERT)-mediated expansion of normal cells; however, the use of these vectors potentially causes unexpected insertional mutagenesis and/or activation of oncogenes. Here, we established normal human fibroblast (hPF) clones retaining non-integrating human artificial chromosome (HAC) vectors harboring the hTERT expression cassette. In hTERT-HAC/hPF clones, we observed the telomerase activity and the suppression of senescent-associated SA-β-galactosidase activity. Furthermore, the hTERT-HAC/hPF clones continued growing beyond 120 days after cloning, whereas the hPF clones retaining the silent hTERT-HAC senesced within 70 days. Thus, hTERT-HAC-mediated episomal expression of hTERT allows the extension of the life-span of human primary cells, implying that gene delivery by non-integrating HAC vectors can be used to control cellular proliferative capacity of primary cultured cells

Separable expansions for local potentials with Coulomb interactions

International Nuclear Information System (INIS)

Adhikari, S.K.

1976-01-01

If two particles are interacting via a short range potential and a repulsive Coulomb potential the t matrix can be written as a sum of the Coulomb and the ''nuclear'' t matrices. In order to solve the three-nucleon problem with Coulomb interactions usually we need a separable representation of this ''nuclear'' t matrix. A recently proposed method for finding a separable expansion for local potentials is here extended to find a rapidly convergent separable expansion, with analytic form factors, for the ''nuclear'' part of the t matrix of a local potential, in the presence of Coulomb interactions. The method is illustrated for a two-term Malfliet-Tjon potential. In each rank the ''nuclear'' phase shift is close to the corresponding phase shift when the Coulomb interaction is switched off

Platelet lysate as a substitute for animal serum for the ex-vivo expansion of mesenchymal stem/stromal cells: present and future.

Science.gov (United States)

Astori, Giuseppe; Amati, Eliana; Bambi, Franco; Bernardi, Martina; Chieregato, Katia; Schäfer, Richard; Sella, Sabrina; Rodeghiero, Francesco

2016-07-13

The use of fetal bovine serum (FBS) as a cell culture supplement is discouraged by regulatory authorities to limit the risk of zoonoses and xenogeneic immune reactions in the transplanted host. Additionally, FBS production came under scrutiny due to animal welfare concerns. Platelet derivatives have been proposed as FBS substitutes for the ex-vivo expansion of mesenchymal stem/stromal cells (MSCs) since platelet-derived growth factors can promote MSC ex-vivo expansion. Platelet-derived growth factors are present in platelet lysate (PL) obtained after repeated freezing-thawing cycles of the platelet-rich plasma or by applying physiological stimuli such as thrombin or CaCl2.PL-expanded MSCs have been used already in the clinic, taking advantage of their faster proliferation compared with FBS-expanded preparations. Should PL be applied to other biopharmaceutical products, its demand is likely to increase dramatically. The use of fresh platelet units for the production of PL raises concerns due to limited availability of platelet donors. Expired units might represent an alternative, but further data are needed to define safety, including pathogen reduction, and functionality of the obtained PL. In addition, relevant questions concerning the definition of PL release criteria, including concentration ranges of specific growth factors in PL batches for various clinical indications, also need to be addressed. We are still far from a common definition of PL and standardized PL manufacture due to our limited knowledge of the mechanisms that mediate PL-promoting cell growth. Here, we concisely discuss aspects of PL as MSC culture supplement as a preliminary step towards an agreed definition of the required characteristics of PL for the requirements of manufacturers and users.

The Relationship between School Achievement and Peer Harassment in Canadian Adolescents: The Importance of Mediating Factors

Science.gov (United States)

Beran, Tanya N.; Lupart, Judy

2009-01-01

The relationship between school achievement and peer harassment was examined using individual and peer characteristics as mediating factors. The sample consisted of adolescents age 12-15 years (n = 4,111) drawn from the Canadian National Longitudinal Survey of Children and Youth, which is a stratified random sample of 22,831 households in Canada.…

Contribution of future urbanisation expansion to flood risk changes

Science.gov (United States)

Bruwier, Martin; Mustafa, Ahmed; Archambeau, Pierre; Erpicum, Sébastien; Pirotton, Michel; Teller, Jacques; Dewals, Benjamin

2016-04-01

The flood risk is expected to increase in the future due to climate change and urban development. Climate change modifies flood hazard and urban development influences exposure and vulnerability to floods. While the influence of climate change on flood risk has been studied widely, the impact of urban development also needs to be considered in a sustainable flood risk management approach. The main goal of this study is the determination of the sensitivity of future flood risk to different urban development scenarios at a relatively short-time horizon in the River Meuse basin in Wallonia (Belgium). From the different scenarios, the expected impact of urban development on flood risk is assessed. Three urban expansion scenarios are developed up to 2030 based on a coupled cellular automata (CA) and agent-based (AB) urban expansion model: (i) business-as-usual, (ii) restrictive and (iii) extreme expansion scenarios. The main factor controlling these scenarios is the future urban land demand. Each urban expansion scenario is developed by considering or not high and/or medium flood hazard zones as a constraint for urban development. To assess the model's performance, it is calibrated for the Meuse River valley (Belgium) to simulate urban expansion between 1990 and 2000. Calibration results are then assessed by comparing the 2000 simulated land-use map and the actual 2000 land-use map. The flood damage estimation for each urban expansion scenario is determined for five flood discharges by overlaying the inundation map resulting from a hydraulic computation and the urban expansion map and by using damage curves and specific prices. The hydraulic model Wolf2D has been extensively validated by comparisons between observations and computational results during flood event .This study focuses only on mobile and immobile prices for urban lands, which are associated to the most severe damages caused by floods along the River Meuse. These findings of this study offers tools to

Conformal expansions and renormalons

Energy Technology Data Exchange (ETDEWEB)

Rathsman, J.

2000-02-07

The coefficients in perturbative expansions in gauge theories are factorially increasing, predominantly due to renormalons. This type of factorial increase is not expected in conformal theories. In QCD conformal relations between observables can be defined in the presence of a perturbative infrared fixed-point. Using the Banks-Zaks expansion the authors study the effect of the large-order behavior of the perturbative series on the conformal coefficients. The authors find that in general these coefficients become factorially increasing. However, when the factorial behavior genuinely originates in a renormalon integral, as implied by a postulated skeleton expansion, it does not affect the conformal coefficients. As a consequence, the conformal coefficients will indeed be free of renormalon divergence, in accordance with previous observations concerning the smallness of these coefficients for specific observables. The authors further show that the correspondence of the BLM method with the skeleton expansion implies a unique scale-setting procedure. The BLM coefficients can be interpreted as the conformal coefficients in the series relating the fixed-point value of the observable with that of the skeleton effective charge. Through the skeleton expansion the relevance of renormalon-free conformal coefficients extends to real-world QCD.

Bearing-Mounting Concept Accommodates Thermal Expansion

Science.gov (United States)

Nespodzany, Robert; Davis, Toren S.

1995-01-01

Pins or splines allow radial expansion without slippage. Design concept for mounting rotary bearing accommodates differential thermal expansion between bearing and any structure(s) to which bearing connected. Prevents buildup of thermal stresses by allowing thermal expansion to occur freely but accommodating expansion in such way not to introduce looseness. Pin-in-slot configuration also maintains concentricity.

Pathogenicity Island Cross Talk Mediated by Recombination Directionality Factors Facilitates Excision from the Chromosome.

Science.gov (United States)

Carpenter, Megan R; Rozovsky, Sharon; Boyd, E Fidelma

2015-12-14

Pathogenicity islands (PAIs) are mobile integrated genetic elements (MIGEs) that contain a diverse range of virulence factors and are essential in the evolution of pathogenic bacteria. PAIs are widespread among bacteria and integrate into the host genome, commonly at a tRNA locus, via integrase-mediated site-specific recombination. The excision of PAIs is the first step in the horizontal transfer of these elements and is not well understood. In this study, we examined the role of recombination directionality factors (RDFs) and their relationship with integrases in the excision of two PAIs essential for Vibrio cholerae host colonization: Vibrio pathogenicity island 1 (VPI-1) and VPI-2. VPI-1 does not contain an RDF, which allowed us to answer the question of whether RDFs are an absolute requirement for excision. We found that an RDF was required for efficient excision of VPI-2 but not VPI-1 and that RDFs can induce excision of both islands. Expression data revealed that the RDFs act as transcriptional repressors to both VPI-1- and VPI-2-encoded integrases. We demonstrated that the RDFs Vibrio excision factor A (VefA) and VefB bind at the attachment sites (overlapping the int promoter region) of VPI-1 and VPI-2, thus supporting this mode of integrase repression. In addition, V. cholerae RDFs are promiscuous due to their dual functions of promoting excision of both VPI-1 and VPI-2 and acting as negative transcriptional regulators of the integrases. This is the first demonstration of cross talk between PAIs mediated via RDFs which reveals the complex interactions that occur between separately acquired MIGEs. Deciphering the mechanisms of pathogenicity island excision is necessary for understanding the evolution and spread of these elements to their nonpathogenic counterparts. Such mechanistic insight would assist in predicting the mobility of uncharacterized genetic elements. This study identified extensive RDF-mediated cross talk between two nonhomologous VPIs and

Stimulatory Effects of Melatonin on Porcine In Vitro Maturation Are Mediated by MT2 Receptor

Directory of Open Access Journals (Sweden)

Sanghoon Lee

2018-05-01

Full Text Available Melatonin is a multifunctional molecule with numerous biological activities. The fact that melatonin modulates the functions of porcine granulosa cells via the MT2 receptor suggests the possibility of MT2 receptor-mediation for melatonin to promote cumulus expansion of porcine cumulus-oocyte complexes (COCs. Therefore, we investigated the presence of MT2 in porcine COCs, and the effects of melatonin with or without selective MT2 antagonists (luzindole and 4-P-PDOT on this process; COCs underwent in vitro maturation culturing with six different conditions (control, melatonin, luzindole, 4-P-PDOT, melatonin + luzindole or melatonin + 4-P-PDOT. Cumulus expansion, oocyte nuclear maturation, and subsequent embryo development after parthenogenetic activation (PA were evaluated. In experiment 1, MT2 was expressed in both oocytes and cumulus cells. In experiment 2, melatonin significantly increased the proportion of complete cumulus expansion (degree 4, which was inhibited by simultaneous addition of either luzindole or 4-P-PDOT. A similar pattern was observed in the expression of genes related to cumulus expansion, apoptosis, and MT2. In experiment 3, no significant difference was observed in immature, degenerate, and MII oocyte rates among the groups. In experiment 4, melatonin significantly increased blastocyst formation rates and total blastocyst cell numbers after PA, but these effects were abolished when either luzindole or 4-P-PDOT was added concomitantly. In conclusion, our results indicate that the MT2 receptor mediated the stimulatory effects of melatonin on porcine cumulus expansion and subsequent embryo development.

Mediating factors of land use change among coffee farmers in a biological corridor

DEFF Research Database (Denmark)

Bosselmann, Aske Skovmand

2012-01-01

Trees in agricultural landscapes are important for the provision of environmental services. This study assesses the loss of shade coffee during a 9 year period in a biological corridor in Costa Rica, and investigates the mediating factors of land use change. Following a conceptual framework....... Additional 224 telephone interviews supplement the data on land use change. Results show a 50% reduction in the coffee area and a corresponding loss of trees. Family labor, age of household head, coffee prices, and use of shade tree products significantly reduce the probability of converting the coffee field...

Arctigenin suppresses receptor activator of nuclear factor κB ligand (RANKL)-mediated osteoclast differentiation in bone marrow-derived macrophages.

Science.gov (United States)

Kim, A-Ram; Kim, Hyuk Soon; Lee, Jeong Min; Choi, Jung Ho; Kim, Se Na; Kim, Do Kyun; Kim, Ji Hyung; Mun, Se Hwan; Kim, Jie Wan; Jeon, Hyun Soo; Kim, Young Mi; Choi, Wahn Soo

2012-05-05

Osteoclasts, multinucleated bone-resorbing cells, are closely associated with bone diseases such as rheumatoid arthritis and osteoporosis. Osteoclasts are derived from hematopoietic precursor cells, and their differentiation is mediated by two cytokines, including macrophage colony stimulating factor and receptor activator of nuclear factor κB ligand (RANKL). Previous studies have shown that arctigenin exhibits an anti-inflammatory effect. However, the effect of arctigenin on osteoclast differentiation is yet to be elucidated. In this study, we found that arctigenin inhibited RANKL-mediated osteoclast differentiation in bone marrow macrophages in a dose-dependent manner and suppressed RANKL-mediated bone resorption. Additionally, the expression of typical marker proteins, such as NFATc1, c-Fos, TRAF6, c-Src, and cathepsin K, were significantly inhibited. Arctigenin inhibited the phosphorylation of Erk1/2, but not p38 and JNK, in a dose-dependent manner. Arctigenin also dramatically suppressed immunoreceptor tyrosine-based activation motif-mediated costimulatory signaling molecules, including Syk and PLCγ2, and Gab2. Notably, arctigenin inhibited the activation of Syk through RANKL stimulation. Furthermore, arctigenin prevented osteoclast differentiation in the calvarial bone of mice following stimulation with lipopolysaccharide. Our results show that arctigenin inhibits osteoclast differentiation in vitro and in vivo. Therefore, arctigenin may be useful for treating rheumatoid arthritis and osteoporosis. Copyright © 2012 Elsevier B.V. All rights reserved.

Umbilical cord blood regulatory T-cell expansion and functional effects of tumor necrosis factor receptor family members OX40 and 4-1BB expressed on artificial antigen-presenting cells

Science.gov (United States)

Harker-Murray, Paul; Porter, Stephen B.; Merkel, Sarah C.; Londer, Aryel; Taylor, Dawn K.; Bina, Megan; Panoskaltsis-Mortari, Angela; Rubinstein, Pablo; Van Rooijen, Nico; Golovina, Tatiana N.; Suhoski, Megan M.; Miller, Jeffrey S.; Wagner, John E.; June, Carl H.; Riley, James L.

2008-01-01

Previously, we showed that human umbilical cord blood (UCB) regulatory T cells (Tregs) could be expanded approximately 100-fold using anti-CD3/28 monoclonal antibody (mAb)–coated beads to provide T-cell receptor and costimulatory signals. Because Treg numbers from a single UCB unit are limited, we explored the use of cell-based artificial antigen-presenting cells (aAPCs) preloaded with anti-CD3/28 mAbs to achieve higher levels of Treg expansion. Compared with beads, aAPCs had similar expansion properties while significantly increasing transforming growth factor β (TGF-β) secretion and the potency of Treg suppressor function. aAPCs modified to coexpress OX40L or 4-1BBL expanded UCB Tregs to a significantly greater extent than bead- or nonmodified aAPC cultures, reaching mean expansion levels exceeding 1250-fold. Despite the high expansion and in contrast to studies using other Treg sources, neither OX40 nor 4-1BB signaling of UCB Tregs reduced in vitro suppression. UCB Tregs expanded with 4-1BBL expressing aAPCs had decreased levels of proapoptotic bim. UCB Tregs expanded with nonmodified or modified aAPCs versus beads resulted in higher survival associated with increased Treg persistence in a xeno-geneic graft-versus-host disease lethality model. These data offer a novel approach for UCB Treg expansion using aAPCs, including those coexpressing OX40L or 4-1BBL. PMID:18645038

δ expansion applied to quantum electrodynamics

International Nuclear Information System (INIS)

Bender, C.M.; Boettcher, S.; Milton, K.A.

1992-01-01

A recently proposed technique known as the δ expansion provides a nonperturbative treatment of a quantum field theory. The δ-expansion approach can be applied to electrodynamics in such a way that local gauge invariance is preserved. In this paper it is shown that for electrodynamic processes involving only external photon lines and no external electron lines the δ expansion is equivalent to a fermion loop expansion. That is, the coefficient of δ n in the δ expansion is precisely the sum of all n-electron-loop Feynman diagrams in a conventional weak-coupling approximation. This equivalence does not extend to processes having external electron lines. When external electron lines are present, the δ expansion is truly nonperturbative and does not have a simple interpretation as a resummation of conventional Feynman diagrams. To illustrate the nonperturbative character of the δ expansion we perform a speculative calculation of the fermion condensate in the massive Schwinger model in the limit of large coupling constant

The Mediator Complex and Lipid Metabolism.

Science.gov (United States)

Zhang, Yi; Xiaoli; Zhao, Xiaoping; Yang, Fajun

2013-03-01

The precise control of gene expression is essential for all biological processes. In addition to DNA-binding transcription factors, numerous transcription cofactors contribute another layer of regulation of gene transcription in eukaryotic cells. One of such transcription cofactors is the highly conserved Mediator complex, which has multiple subunits and is involved in various biological processes through directly interacting with relevant transcription factors. Although the current understanding on the biological functions of Mediator remains incomplete, research in the past decade has revealed an important role of Mediator in regulating lipid metabolism. Such function of Mediator is dependent on specific transcription factors, including peroxisome proliferator-activated receptor-gamma (PPARγ) and sterol regulatory element-binding proteins (SREBPs), which represent the master regulators of lipid metabolism. The medical significance of these findings is apparent, as aberrant lipid metabolism is intimately linked to major human diseases, such as type 2 diabetes and cardiovascular disease. Here, we briefly review the functions and molecular mechanisms of Mediator in regulation of lipid metabolism.

Asymptotic Expansions of Generalized Nevanlinna Functions and their Spectral Properties

NARCIS (Netherlands)

Derkach, Vladimir; Hassi, Seppo; de Snoo, Hendrik

2007-01-01

Asymptotic expansions of generalized Nevanlinna functions Q are investigated by means of a factorization model involving a part of the generalized zeros and poles of nonpositive type of the function Q. The main results in this paper arise from the explicit construction of maximal Jordan chains in

Platelet Vascular Endothelial Growth Factor is a Potential Mediator of Transfusion-Related Acute Lung Injury.

Science.gov (United States)

Maloney, James P; Ambruso, Daniel R; Voelkel, Norbert F; Silliman, Christopher C

The occurrence of non-hemolytic transfusion reactions is highest with platelet and plasma administration. Some of these reactions are characterized by endothelial leak, especially transfusion related acute lung injury (TRALI). Elevated concentrations of inflammatory mediators secreted by contaminating leukocytes during blood product storage may contribute to such reactions, but platelet-secreted mediators may also contribute. We hypothesized that platelet storage leads to accumulation of the endothelial permeability mediator vascular endothelial growth factor (VEGF), and that intravascular administration of exogenous VEGF leads to extensive binding to its lung receptors. Single donor, leukocyte-reduced apheresis platelet units were sampled over 5 days of storage. VEGF protein content of the centrifuged supernatant was determined by ELISA, and the potential contribution of VEGF from contaminating leukocytes was quantified. Isolated-perfused rat lungs were used to study the uptake of radiolabeled VEGF administered intravascularly, and the effect of unlabeled VEGF on lung leak. There was a time-dependent release of VEGF into the plasma fraction of the platelet concentrates (62 ± 9 pg/ml on day one, 149 ± 23 pg/ml on day 5; mean ± SEM, pproducts.

FRACTAL DIMENSION OF URBAN EXPANSION BASED ON REMOTE SENSING IMAGES

Directory of Open Access Journals (Sweden)

IACOB I. CIPRIAN

2012-11-01

Full Text Available Fractal Dimension of Urban Expansion Based on Remote Sensing Images: In Cluj-Napoca city the process of urbanization has been accelerated during the years and implication of local authorities reflects a relevant planning policy. A good urban planning framework should take into account the society demands and also it should satisfy the natural conditions of local environment. The expansion of antropic areas it can be approached by implication of 5D variables (time as a sequence of stages, space: with x, y, z and magnitude of phenomena into the process, which will allow us to analyse and extract the roughness of city shape. Thus, to improve the decision factor we take a different approach in this paper, looking at geometry and scale composition. Using the remote sensing (RS and GIS techniques we manage to extract a sequence of built-up areas (from 1980 to 2012 and used the result as an input for modelling the spatialtemporal changes of urban expansion and fractal theory to analysed the geometric features. Taking the time as a parameter we can observe behaviour and changes in urban landscape, this condition have been known as self-organized – a condition which in first stage the system was without any turbulence (before the antropic factor and during the time tend to approach chaotic behaviour (entropy state without causing an disequilibrium in the main system.

Clumping factor A-mediated virulence during Staphylococcus aureus infection is retained despite fibrinogen depletion.

Science.gov (United States)

Palmqvist, Niklas; Josefsson, Elisabet; Tarkowski, Andrzej

2004-02-01

Clumping factor A (ClfA), a fibrinogen-binding protein expressed on the Staphylococcus aureus cell surface, has previously been shown to act as a virulence factor in experimental septic arthritis. Although the interaction between ClfA and fibrinogen is assumed to be of importance for the virulence of S. aureus, this has not been demonstrated in any in vivo model of infection. Therefore, the objective of this study was to investigate the contribution of this interaction to ClfA-mediated virulence in murine S. aureus-induced arthritis. Ancrod, a serine protease with thrombin-like activity, was used to induce in vivo depletion of fibrinogen in mice. Ancrod treatment significantly aggravated septic arthritis following inoculation with a ClfA-expressing strain (Newman) compared to control treatment. Also, ancrod treatment tended to enhance the arthritis induced by a clfA mutant strain (DU5876), indicating that fibrinogen depletion exacerbates septic arthritis in a ClfA-independent manner. Most importantly, the ClfA-expressing strain was much more arthritogenic than the isogenic clfA mutant, following inoculation of fibrinogen-depleted mice. This finding indicates that the interaction between ClfA and free fibrinogen is not required for ClfA-mediated functions contributing to S. aureus virulence. It is conceivable that ClfA contributes to the virulence of S. aureus through interactions with other host ligands than fibrinogen.

Disruption of Tumor Necrosis Factor Receptor-Associated Factor 5 Exacerbates Murine Experimental Colitis via Regulating T Helper Cell-Mediated Inflammation

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Jian Shang

2016-01-01

Full Text Available Tumor necrosis factor (TNF receptor-associated factor 5 (TRAF5 is a key mediator of TNF receptor superfamily members and is important in both T helper (Th cell immunity and the regulation of multiple signaling pathways. To clarify TRAF5’s influence on inflammatory bowel diseases (IBDs, we investigated TRAF5 deficiency’s effect on dextran sulfate sodium- (DSS- induced colitis. Colitis was induced in TRAF5 knockout (KO mice and their wild-type (WT littermates by administering 3% DSS orally for 7 days. The mice were then sacrificed, and their colons were removed. Our data suggested that KO mice were more susceptible to DSS-induced colitis. TRAF5 deficiency significantly enhanced IFN-γ, IL-4, and IL-17a mRNA and protein levels in the colons of DSS-fed mice, and the mRNA expression of T-bet and GATA-3 was also markedly elevated. However, ROR-α and ROR-γt mRNA levels did not differ between DSS-induced KO and WT mice. Flow cytometry showed increased frequencies of Th2 and IFN-γ/IL-17a-coproducing CD4+ T cells in the colons of DSS-induced KO mice. Additionally, TRAF5 deficiency significantly enhanced the activation of NF-κB in CD4+ T cells after DSS administration. These results indicated that TRAF5 deficiency significantly aggravated DSS-induced colitis, most likely by regulating Th cell-mediated inflammation.

Accelerating the loop expansion

International Nuclear Information System (INIS)

Ingermanson, R.

1986-01-01

This thesis introduces a new non-perturbative technique into quantum field theory. To illustrate the method, I analyze the much-studied phi 4 theory in two dimensions. As a prelude, I first show that the Hartree approximation is easy to obtain from the calculation of the one-loop effective potential by a simple modification of the propagator that does not affect the perturbative renormalization procedure. A further modification then susggests itself, which has the same nice property, and which automatically yields a convex effective potential. I then show that both of these modifications extend naturally to higher orders in the derivative expansion of the effective action and to higher orders in the loop-expansion. The net effect is to re-sum the perturbation series for the effective action as a systematic ''accelerated'' non-perturbative expansion. Each term in the accelerated expansion corresponds to an infinite number of terms in the original series. Each term can be computed explicitly, albeit numerically. Many numerical graphs of the various approximations to the first two terms in the derivative expansion are given. I discuss the reliability of the results and the problem of spontaneous symmetry-breaking, as well as some potential applications to more interesting field theories. 40 refs

Thermal expansion data

International Nuclear Information System (INIS)

Taylor, D.

1984-01-01

This paper gives regression data for a modified second order polynomial fitted to the expansion data of, and percentage expansions for dioxides with (a) the fluorite and antifluorite structure: AmO 2 , BkO 2 , CeO 2 , CmO 2 , HfO 2 , Li 2 O, NpO 2 , PrO 2 , PuO 2 , ThO 2 , UO 2 , ZrO 2 , and (b) the rutile structure: CrO 2 , GeO 2 , IrO 2 , MnO 2 , NbO 2 , PbO 2 , SiO 2 , SnO 2 , TeO 2 , TiO 2 and VO 2 . Reduced expansion curves for the dioxides showed only partial grouping into iso-electronic series for the fluorite structures and showed that the 'law of corresponding states' did not apply to the rutile structures. (author)

The effect of individual factors on health behaviors among college students: the mediating effects of eHealth literacy.

Science.gov (United States)

Hsu, WanChen; Chiang, ChiaHsun; Yang, ShuChing

2014-12-12

College students' health behavior is a topic that deserves attention. Individual factors and eHealth literacy may affect an individual's health behaviors. The integrative model of eHealth use (IMeHU) provides a parsimonious account of the connections among the digital divide, health care disparities, and the unequal distribution and use of communication technologies. However, few studies have explored the associations among individual factors, eHealth literacy, and health behaviors, and IMeHU has not been empirically investigated. This study examines the associations among individual factors, eHealth literacy, and health behaviors using IMeHU. The Health Behavior Scale is a 12-item instrument developed to measure college students' eating, exercise, and sleep behaviors. The eHealth Literacy Scale is a 12-item instrument designed to measure college students' functional, interactive, and critical eHealth literacy. A nationally representative sample of 525 valid college students in Taiwan was surveyed. A questionnaire was administered to collect background information about participants' health status, degree of health concern, major, and the frequency with which they engaged in health-related discussions. This study used Amos 6.0 to conduct a confirmatory factor analysis to identify the best measurement models for the eHealth Literacy Scale and the Health Behavior Scale. We then conducted a multiple regression analysis to examine the associations among individual factors, eHealth literacy, and health behaviors. Additionally, causal steps approach was used to explore indirect (mediating) effects and Sobel tests were used to test the significance of the mediating effects. The study found that perceptions of better health status (t520=2.14-6.12, PeHealth literacy and adoption of healthy eating, exercise, and sleep behaviors. Moreover, eHealth literacy played an intermediary role in the association between individual factors and health behaviors (Sobel test=2.09-2.72, Pe

Thermal expansion of beryllium oxide

International Nuclear Information System (INIS)

Solodukhin, A.V.; Kruzhalov, A.V.; Mazurenko, V.G.; Maslov, V.A.; Medvedev, V.A.; Polupanova, T.I.

1987-01-01

Precise measurements of temperature dependence of the coefficient of linear expansion in the 22-320 K temperature range on beryllium oxide monocrystals are conducted. A model of thermal expansion is suggested; the range of temperature dependence minimum of the coefficient of thermal expansion is well described within the frames of this model. The results of the experiment may be used for investigation of thermal stresses in crystals

Species-specific chitin-binding module 18 expansion in the amphibian pathogen Batrachochytrium dendrobatidis.

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Abramyan, John; Stajich, Jason E

2012-01-01

Batrachochytrium dendrobatidis is the causative agent of chytridiomycosis, which is considered one of the driving forces behind the worldwide decline in populations of amphibians. As a member of the phylum Chytridiomycota, B. dendrobatidis has diverged significantly to emerge as the only pathogen of adult vertebrates. Such shifts in lifestyle are generally accompanied by various degrees of genomic modifications, yet neither its mode of pathogenicity nor any factors associated with it have ever been identified. Presented here is the identification and characterization of a unique expansion of the carbohydrate-binding module family 18 (CBM18), specific to B. dendrobatidis. CBM (chitin-binding module) expansions have been likened to the evolution of pathogenicity in a variety of fungus species, making this expanded group a prime candidate for the identification of potential pathogenicity factors. Furthermore, the CBM18 expansions are confined to three categories of genes, each having been previously implicated in host-pathogen interactions. These correlations highlight this specific domain expansion as a potential key player in the mode of pathogenicity in this unique fungus. The expansion of CBM18 in B. dendrobatidis is exceptional in its size and diversity compared to other pathogenic species of fungi, making this genomic feature unique in an evolutionary context as well as in pathogenicity. Amphibian populations are declining worldwide at an unprecedented rate. Although various factors are thought to contribute to this phenomenon, chytridiomycosis has been identified as one of the leading causes. This deadly fungal disease is cause by Batrachochytrium dendrobatidis, a chytrid fungus species unique in its pathogenicity and, furthermore, its specificity to amphibians. Despite more than two decades of research, the biology of this fungus species and its deadly interaction with amphibians had been notoriously difficult to unravel. Due to the alarming rate of worldwide

Spherical and cylindrical cavity expansion models based prediction of penetration depths of concrete targets.

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Xiaochao Jin

Full Text Available The cavity expansion theory is most widely used to predict the depth of penetration of concrete targets. The main purpose of this work is to clarify the differences between the spherical and cylindrical cavity expansion models and their scope of application in predicting the penetration depths of concrete targets. The factors that influence the dynamic cavity expansion process of concrete materials were first examined. Based on numerical results, the relationship between expansion pressure and velocity was established. Then the parameters in the Forrestal's formula were fitted to have a convenient and effective prediction of the penetration depth. Results showed that both the spherical and cylindrical cavity expansion models can accurately predict the depth of penetration when the initial velocity is lower than 800 m/s. However, the prediction accuracy decreases with the increasing of the initial velocity and diameters of the projectiles. Based on our results, it can be concluded that when the initial velocity is higher than the critical velocity, the cylindrical cavity expansion model performs better than the spherical cavity expansion model in predicting the penetration depth, while when the initial velocity is lower than the critical velocity the conclusion is quite the contrary. This work provides a basic principle for selecting the spherical or cylindrical cavity expansion model to predict the penetration depth of concrete targets.

Convergence of mayer expansions

International Nuclear Information System (INIS)

Brydges, D.C.

1986-01-01

The tree graph bound of Battle and Federbush is extended and used to provide a simple criterion for the convergence of (iterated) Mayer expansions. As an application estimates on the radius of convergence of the Mayer expansion for the two-dimensional Yukawa gas (nonstable interaction) are obtained

Native low-density lipoprotein uptake by macrophage colony-stimulating factor-differentiated human macrophages is mediated by macropinocytosis and micropinocytosis.

Science.gov (United States)

Anzinger, Joshua J; Chang, Janet; Xu, Qing; Buono, Chiara; Li, Yifu; Leyva, Francisco J; Park, Bum-Chan; Greene, Lois E; Kruth, Howard S

2010-10-01

To examine the pinocytotic pathways mediating native low-density lipoprotein (LDL) uptake by human macrophage colony-stimulating factor-differentiated macrophages (the predominant macrophage phenotype in human atherosclerotic plaques). We identified the kinase inhibitor SU6656 and the Rho GTPase inhibitor toxin B as inhibitors of macrophage fluid-phase pinocytosis of LDL. Assessment of macropinocytosis by time-lapse microscopy revealed that both drugs almost completely inhibited macropinocytosis, although LDL uptake and cholesterol accumulation by macrophages were only partially inhibited (approximately 40%) by these agents. Therefore, we investigated the role of micropinocytosis in mediating LDL uptake in macrophages and identified bafilomycin A1 as an additional partial inhibitor (approximately 40%) of macrophage LDL uptake that targeted micropinocytosis. When macrophages were incubated with both bafilomycin A1 and SU6656, inhibition of LDL uptake was additive (reaching 80%), showing that these inhibitors target different pathways. Microscopic analysis of fluid-phase uptake pathways in these macrophages confirmed that LDL uptake occurs through both macropinocytosis and micropinocytosis. Our findings show that human macrophage colony-stimulating factor-differentiated macrophages take up native LDL by macropinocytosis and micropinocytosis, underscoring the importance of both pathways in mediating LDL uptake by these cells.

Role of human-mediated dispersal in the spread of the pinewood nematode in China.

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Christelle Robinet

Full Text Available Intensification of world trade is responsible for an increase in the number of alien species introductions. Human-mediated dispersal promotes not only introductions but also expansion of the species distribution via long-distance dispersal. Thus, understanding the role of anthropogenic pathways in the spread of invading species has become one of the most important challenges nowadays.We analysed the invasion pattern of the pinewood nematode in China based on invasion data from 1982 to 2005 and monitoring data on 7 locations over 15 years. Short distance spread mediated by long-horned beetles was estimated at 7.5 km per year. Infested sites located further away represented more than 90% of observations and the mean long distance spread was estimated at 111-339 km. Railways, river ports, and lakes had significant effects on the spread pattern. Human population density levels explained 87% of the variation in the invasion probability (P<0.05. Since 2001, the number of new records of the nematode was multiplied by a factor of 5 and the spread distance by a factor of 2. We combined a diffusion model to describe the short distance spread with a stochastic, individual based model to describe the long distance jumps. This combined model generated an error of only 13% when used to predict the presence of the nematode. Under two climate scenarios (stable climate or moderate warming, projections of the invasion probability suggest that this pest could expand its distribution 40-55% by 2025.This study provides evidence that human-induced dispersal plays a fundamental role in the spread of the pinewood nematode, and appropriate control measures should be taken to stop or slow its expansion. This model can be applied to Europe, where the nematode had been introduced later, and is currently expanding its distribution. Similar models could also be derived for other species that could be accidentally transported by humans.

The relationship between human resource development factors, career growth and turnover intention: The mediating role of organizational commitment

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Muhammad Shahid Nawaz

2016-02-01

Full Text Available Retaining the best employees is of high concern for most organizations and this issue has become a significant focus of attention for many researchers. For this reason, this paper discusses different factors which influence the employee turnover intention-behavior in the organization, specifically to examine the effect of salary, performance appraisal, training & development and career growth on turnover intention. In addition, based on the social exchange theory this paper explains the mediating role of organizational commitment in the relationship between human resource development factors, career growth and turnover intention. A cross sectional, survey data study is undertaken to investigate the relationships in a sample of 270 full time faculty members employed in different private universities of Pakistan. Partial Least Square two step path modeling is used to test the direct and the indirect hypothesis of the study. The results of PLS (SEM path modeling reveal that human resource development factors specially salary and performance appraisal were negatively associated with turnover intention. In addition, the results also indicate that career growth had significant relationships with turnover intention. Moreover, out of four dimensions of career growth, only two dimensions, namely promotion speed and remuneration growth, have strong influence on turnover intention. Finally, in terms of organizational commitment as mediating variable between the relationships of salary, performance appraisal, career growth and turnover intention, four out of six variables indicate partial mediation including career growth (career goal progress, career growth (promotion speed, career growth (remuneration growth and performance appraisal.

Cosmological models constructed by van der Waals fluid approximation and volumetric expansion

Science.gov (United States)

Samanta, G. C.; Myrzakulov, R.

The universe modeled with van der Waals fluid approximation, where the van der Waals fluid equation of state contains a single parameter ωv. Analytical solutions to the Einstein’s field equations are obtained by assuming the mean scale factor of the metric follows volumetric exponential and power-law expansions. The model describes a rapid expansion where the acceleration grows in an exponential way and the van der Waals fluid behaves like an inflation for an initial epoch of the universe. Also, the model describes that when time goes away the acceleration is positive, but it decreases to zero and the van der Waals fluid approximation behaves like a present accelerated phase of the universe. Finally, it is observed that the model contains a type-III future singularity for volumetric power-law expansion.

Education and risk of coronary heart disease: Assessment of mediation by behavioural risk factors using the additive hazards model

DEFF Research Database (Denmark)

Nordahl, H; Rod, NH; Frederiksen, BL

2013-01-01

seven Danish cohort studies were linked to registry data on education and incidence of CHD. Mediation by smoking, low physical activity, and body mass index (BMI) on the association between education and CHD were estimated by applying newly proposed methods for mediation based on the additive hazards...... % CI: 12, 22) for women and 37 (95 % CI: 28, 46) for men could be ascribed to the pathway through smoking. Further, 39 (95 % CI: 30, 49) cases for women and 94 (95 % CI: 79, 110) cases for men could be ascribed to the pathway through BMI. The effects of low physical activity were negligible. Using...... contemporary methods, the additive hazards model, for mediation we indicated the absolute numbers of CHD cases prevented when modifying smoking and BMI. This study confirms previous claims based on the Cox proportional hazards model that behavioral risk factors partially mediates the effect of education on CHD...

Maternal Factors as Moderators or Mediators of PTSD Symptoms in Very Young Children: A Two-Year Prospective Study

OpenAIRE

Scheeringa, Michael S.; Myers, Leann; Putnam, Frank W.; Zeanah, Charles H.

2015-01-01

Research has suggested that parenting behaviors and other parental factors impact the long-term outcome of children’s posttraumatic stress disorder (PTSD) symptoms. In a sample of 62 children between the ages of one and six who experienced life-threatening traumas, PTSD was measured prospectively two years apart. Seven maternal factors were measured in a multi-method, multi-informant design. Both moderation and mediation models, with different theoretical and mechanism implications, were test...

Effects of current density and electrolyte temperature on the volume expansion factor of anodic alumina formed in oxalic acid

International Nuclear Information System (INIS)

Zhou, F.; Baron-Wiecheć, A.; Garcia-Vergara, S.J.; Curioni, M.; Habazaki, H.; Skeldon, P.; Thompson, G.E.

2012-01-01

The formation of porous anodic alumina in 0.4 M oxalic acid is investigated over a range of current density and electrolyte temperature using sputtering-deposited substrates containing tungsten tracer layers. The findings reveal volume expansion factors and efficiencies of film growth that increase with the increase of the current density and decrease of the temperature. Pore generation by the flow of the anodic alumina in the barrier layer toward the pore walls is proposed to dominate at relatively high current densities (above ∼2 mA cm −2 ), with tungsten tracer species being retained within films. Conversely, losses of tungsten species occur at lower current densities, possibly due to increased field-assisted ejection of Al 3+ ions and/or field-assisted dissolution of the anodic alumina.

The transcription factor MEF2C mediates cardiomyocyte hypertrophy induced by IGF-1 signaling

Energy Technology Data Exchange (ETDEWEB)

Munoz, Juan Pablo; Collao, Andres; Chiong, Mario; Maldonado, Carola; Adasme, Tatiana; Carrasco, Loreto; Ocaranza, Paula; Bravo, Roberto; Gonzalez, Leticia; Diaz-Araya, Guillermo [Centro FONDAP Estudios Moleculares de la Celula, Facultad de Medicina, Universidad de Chile, Santiago 8380492 (Chile); Facultad de Ciencias Quimicas y Farmaceuticas, Facultad de Medicina, Universidad de Chile, Santiago 8380492 (Chile); Hidalgo, Cecilia [Centro FONDAP Estudios Moleculares de la Celula, Facultad de Medicina, Universidad de Chile, Santiago 8380492 (Chile); Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago 8380492 (Chile); Lavandero, Sergio, E-mail: slavander@uchile.cl [Centro FONDAP Estudios Moleculares de la Celula, Facultad de Medicina, Universidad de Chile, Santiago 8380492 (Chile); Facultad de Ciencias Quimicas y Farmaceuticas, Facultad de Medicina, Universidad de Chile, Santiago 8380492 (Chile); Instituto de Ciencias Biomedicas, Facultad de Medicina, Universidad de Chile, Santiago 8380492 (Chile)

2009-10-09

Myocyte enhancer factor 2C (MEF2C) plays an important role in cardiovascular development and is a key transcription factor for cardiac hypertrophy. Here, we describe MEF2C regulation by insulin-like growth factor-1 (IGF-1) and its role in IGF-1-induced cardiac hypertrophy. We found that IGF-1 addition to cultured rat cardiomyocytes activated MEF2C, as evidenced by its increased nuclear localization and DNA binding activity. IGF-1 stimulated MEF2 dependent-gene transcription in a time-dependent manner, as indicated by increased MEF2 promoter-driven reporter gene activity; IGF-1 also induced p38-MAPK phosphorylation, while an inhibitor of p38-MAPK decreased both effects. Additionally, inhibitors of phosphatidylinositol 3-kinase and calcineurin prevented IGF-1-induced MEF2 transcriptional activity. Via MEF2C-dependent signaling, IGF-1 also stimulated transcription of atrial natriuretic factor and skeletal {alpha}-actin but not of fos-lux reporter genes. These novel data suggest that MEF2C activation by IGF-1 mediates the pro-hypertrophic effects of IGF-1 on cardiac gene expression.

The transcription factor MEF2C mediates cardiomyocyte hypertrophy induced by IGF-1 signaling

International Nuclear Information System (INIS)

Munoz, Juan Pablo; Collao, Andres; Chiong, Mario; Maldonado, Carola; Adasme, Tatiana; Carrasco, Loreto; Ocaranza, Paula; Bravo, Roberto; Gonzalez, Leticia; Diaz-Araya, Guillermo; Hidalgo, Cecilia; Lavandero, Sergio

2009-01-01

Myocyte enhancer factor 2C (MEF2C) plays an important role in cardiovascular development and is a key transcription factor for cardiac hypertrophy. Here, we describe MEF2C regulation by insulin-like growth factor-1 (IGF-1) and its role in IGF-1-induced cardiac hypertrophy. We found that IGF-1 addition to cultured rat cardiomyocytes activated MEF2C, as evidenced by its increased nuclear localization and DNA binding activity. IGF-1 stimulated MEF2 dependent-gene transcription in a time-dependent manner, as indicated by increased MEF2 promoter-driven reporter gene activity; IGF-1 also induced p38-MAPK phosphorylation, while an inhibitor of p38-MAPK decreased both effects. Additionally, inhibitors of phosphatidylinositol 3-kinase and calcineurin prevented IGF-1-induced MEF2 transcriptional activity. Via MEF2C-dependent signaling, IGF-1 also stimulated transcription of atrial natriuretic factor and skeletal α-actin but not of fos-lux reporter genes. These novel data suggest that MEF2C activation by IGF-1 mediates the pro-hypertrophic effects of IGF-1 on cardiac gene expression.

State Medicaid Expansion Tobacco Cessation Coverage and Number of Adult Smokers Enrolled in Expansion Coverage - United States, 2016.

Science.gov (United States)

DiGiulio, Anne; Haddix, Meredith; Jump, Zach; Babb, Stephen; Schecter, Anna; Williams, Kisha-Ann S; Asman, Kat; Armour, Brian S

2016-12-09

In 2015, 27.8% of adult Medicaid enrollees were current cigarette smokers, compared with 11.1% of adults with private health insurance, placing Medicaid enrollees at increased risk for smoking-related disease and death (1). In addition, smoking-related diseases are a major contributor to Medicaid costs, accounting for about 15% (>$39 billion) of annual Medicaid spending during 2006-2010 (2). Individual, group, and telephone counseling and seven Food and Drug Administration (FDA)-approved medications are effective treatments for helping tobacco users quit (3). Insurance coverage for tobacco cessation treatments is associated with increased quit attempts, use of cessation treatments, and successful smoking cessation (3); this coverage has the potential to reduce Medicaid costs (4). However, barriers such as requiring copayments and prior authorization for treatment can impede access to cessation treatments (3,5). As of July 1, 2016, 32 states (including the District of Columbia) have expanded Medicaid eligibility through the Patient Protection and Affordable Care Act (ACA),* ,† which has increased access to health care services, including cessation treatments (5). CDC used data from the Centers for Medicare and Medicaid Services (CMS) Medicaid Budget and Expenditure System (MBES) and the Behavioral Risk Factor Surveillance System (BRFSS) to estimate the number of adult smokers enrolled in Medicaid expansion coverage. To assess cessation coverage among Medicaid expansion enrollees, the American Lung Association collected data on coverage of, and barriers to accessing, evidence-based cessation treatments. As of December 2015, approximately 2.3 million adult smokers were newly enrolled in Medicaid because of Medicaid expansion. As of July 1, 2016, all 32 states that have expanded Medicaid eligibility under ACA covered some cessation treatments for all Medicaid expansion enrollees, with nine states covering all nine cessation treatments for all Medicaid expansion

Thermal linear expansion coefficient of structural graphites

International Nuclear Information System (INIS)

Virgil'ev, Yu.S.

1995-01-01

The data now available on radiation induced changes of linear thermal expansion coefficients (CTE) for native structural carbon materials (SCM) irradiated with high fluences are summarized. For different types of native and foreign SCM dose dependences of CTE changes in the temperature range of 300...1600 K and at fluences up to (2...3)x10 22 n/cm 2 (E>0.18 meV) are compared. On the base of this comparison factors defined the CTE changes under neutron irradiation are revealed and the explanation of observed phenomena is offered. Large number of the factors revealed does not allowed to calculate CTE radiation induced changes. 39 refs.; 16 figs.; 5 tabs

Simulating the Range Expansion of Spartina alterniflora in Ecological Engineering through Constrained Cellular Automata Model and GIS

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Zongsheng Zheng

2015-01-01

Full Text Available Environmental factors play an important role in the range expansion of Spartina alterniflora in estuarine salt marshes. CA models focusing on neighbor effect often failed to account for the influence of environmental factors. This paper proposed a CCA model that enhanced CA model by integrating constrain factors of tidal elevation, vegetation density, vegetation classification, and tidal channels in Chongming Dongtan wetland, China. Meanwhile, a positive feedback loop between vegetation and sedimentation was also considered in CCA model through altering the tidal accretion rate in different vegetation communities. After being validated and calibrated, the CCA model is more accurate than the CA model only taking account of neighbor effect. By overlaying remote sensing classification and the simulation results, the average accuracy increases to 80.75% comparing with the previous CA model. Through the scenarios simulation, the future of Spartina alterniflora expansion was analyzed. CCA model provides a new technical idea and method for salt marsh species expansion and control strategies research.

Three-Dimensional Force Measurements During Rapid Palatal Expansion in Sus scrofa

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Kelly Goeckner

2016-04-01

Full Text Available Rapid palatal expansion is an orthodontic procedure widely used to correct the maxillary arch. However, its outcome is significantly influenced by factors that show a high degree of variability amongst patients. The traditional treatment methodology is based on an intuitive and heuristic treatment approach because the forces applied in the three dimensions are indeterminate. To enable optimal and individualized treatment, it is essential to measure the three-dimensional (3D forces and displacements created by the expander. This paper proposes a method for performing these 3D measurements using a single embedded strain sensor, combining experimental measurements of strain in the palatal expander with 3D finite element analysis (FEA. The method is demonstrated using the maxillary jaw from a freshly euthanized pig (Sus scrofa and a hyrax-design rapid palatal expander (RPE appliance with integrated strain gage. The strain gage measurements are recorded using a computer interface, following which the expansion forces and extent of expansion are estimated by FEA. A total activation of 2.0 mm results in peak total force of about 100 N—almost entirely along the direction of expansion. The results also indicate that more than 85% of the input activation is immediately transferred to the palate and/or teeth. These studies demonstrate a method for assessing and individualizing expansion magnitudes and forces during orthopedic expansion of the maxilla. This provides the basis for further development of smart orthodontic appliances that provide real-time readouts of forces and movements, which will allow personalized, optimal treatment.

Rupatadine inhibits inflammatory mediator release from human laboratory of allergic diseases 2 cultured mast cells stimulated by platelet-activating factor.

Science.gov (United States)

Alevizos, Michail; Karagkouni, Anna; Vasiadi, Magdalini; Sismanopoulos, Nikolaos; Makris, Michael; Kalogeromitros, Dimitrios; Theoharides, Theoharis C

2013-12-01

Mast cells are involved in allergy and inflammation by the secretion of multiple mediators, including histamine, cytokines, and platelet-activating factor (PAF), in response to different triggers, including emotional stress. PAF has been associated with allergic inflammation, but there are no clinically available PAF inhibitors. To investigate whether PAF could stimulate human mast cell mediator release and whether rupatadine (RUP), a dual histamine-1 and PAF receptor antagonist, could inhibit the effect of PAF on human mast cells. Laboratory of allergic diseases 2 cultured mast cells were stimulated with PAF (0.001, 0.01, and 0.1 μmol/L) and substance P (1 μmol/L) with or without pretreatment with RUP (2.5 and 25 μmol/L), which was added 10 minutes before stimulation. Release of β-hexosaminidase was measured in supernatant fluid by spectrophotoscopy, and histamine, interleukin-8, and tumor necrosis factor were measured by enzyme-linked immunosorbent assay. PAF stimulated a statistically significant release of histamine, interleukin-8, and tumor necrosis factor (0.001-0.1 μmol/L) that was comparable to that stimulated by substance P. Pretreatment with RUP (25 μmol/L) for 10 minutes inhibited this effect. In contrast, pretreatment of laboratory of allergic diseases 2 cells with diphenhydramine (25 μmol/L) did not inhibit mediator release, suggesting that the effect of RUP was not due to its antihistaminic effect. PAF stimulates human mast cell release of proinflammatory mediators that is inhibited by RUP. This action endows RUP with additional properties in treating allergic inflammation. Copyright © 2013 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Role of 5'TG3'-interacting factors (TGIFs) in Vorinostat (HDAC inhibitor)-mediated Corneal Fibrosis Inhibition.

Science.gov (United States)

Sharma, Ajay; Sinha, Nishant R; Siddiqui, Saad; Mohan, Rajiv R

2015-01-01

We have previously reported that vorinostat, an FDA-approved, clinically used histone deacetylase (HDAC) inhibitor, attenuates corneal fibrosis in vivo in rabbits by blocking transforming growth factor β (TGFβ). The 5'TG3'-interacting factors (TGIFs) are transcriptional repressors of TGFβ1 signaling via the Smad pathway. The present study was designed to explore the expression of TGIFs in human corneal fibroblasts and to investigate their role in mediating the antifibrotic effect of vorinostat. Human corneal fibroblast cultures were generated from donor corneas. RNA isolation, cDNA preparation, and PCR were performed to detect the presence of TGIF1 and TGIF2 transcripts. The cultures were exposed to vorinostat (2.5 µM) to test its effect on TGIF mRNA and protein levels using qPCR and immunoblotting. Myofibroblast formation was induced with TGFβ1 (5 ng/ml) treatment under serum-free conditions. The changes in fibrosis parameters were quantified by measuring fibrosis marker α-smooth muscle actin (αSMA) mRNA and protein levels with qPCR, immunostaining, and immunoblotting. Smad2/3/4 and TGIF knockdowns were performed using pre-validated RNAi/siRNAs and a commercially available transfection reagent. Human corneal fibroblasts showed the expression of TGIF1 and TGIF2. Vorinostat (2.5 µM) caused a 2.8-3.3-fold increase in TGIF1 and TGIF2 mRNA levels and a 1.4-1.8-fold increase in TGIF1 and TGIF2 protein levels. Vorinostat treatment also caused a significant increase in acetylhistone H3 and acetylhistone H4. Vorinostat-induced increases in TGIF1 and TGIF2 were accompanied by a concurrent decrease in corneal fibrosis, as indicated by a decrease in αSMA mRNA by 83±7.7% and protein levels by 97±5%. The RNAi-mediated knockdown of Smad2, Smad3, and Smad4 markedly attenuated TGFβ1-evoked transdifferentiation of fibroblasts to myofibroblasts. The siRNA-mediated knockdown of TGIF1 and TGIF2 neutralized vorinostat-evoked decreases in αSMA mRNA by 31%-45% and protein

Macrophage Migration Inhibitory Factor Mediates Proliferative GN via CD74

Science.gov (United States)

Djudjaj, Sonja; Lue, Hongqi; Rong, Song; Papasotiriou, Marios; Klinkhammer, Barbara M.; Zok, Stephanie; Klaener, Ole; Braun, Gerald S.; Lindenmeyer, Maja T.; Cohen, Clemens D.; Bucala, Richard; Tittel, Andre P.; Kurts, Christian; Moeller, Marcus J.; Floege, Juergen; Ostendorf, Tammo

2016-01-01

Pathologic proliferation of mesangial and parietal epithelial cells (PECs) is a hallmark of various glomerulonephritides. Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine that mediates inflammation by engagement of a receptor complex involving the components CD74, CD44, CXCR2, and CXCR4. The proliferative effects of MIF may involve CD74 together with the coreceptor and PEC activation marker CD44. Herein, we analyzed the effects of local glomerular MIF/CD74/CD44 signaling in proliferative glomerulonephritides. MIF, CD74, and CD44 were upregulated in the glomeruli of patients and mice with proliferative glomerulonephritides. During disease, CD74 and CD44 were expressed de novo in PECs and colocalized in both PECs and mesangial cells. Stress stimuli induced MIF secretion from glomerular cells in vitro and in vivo, in particular from podocytes, and MIF stimulation induced proliferation of PECs and mesangial cells via CD74. In murine crescentic GN, Mif-deficient mice were almost completely protected from glomerular injury, the development of cellular crescents, and the activation and proliferation of PECs and mesangial cells, whereas wild-type mice were not. Bone marrow reconstitution studies showed that deficiency of both nonmyeloid and bone marrow–derived Mif reduced glomerular cell proliferation and injury. In contrast to wild-type mice, Cd74-deficient mice also were protected from glomerular injury and ensuing activation and proliferation of PECs and mesangial cells. Our data suggest a novel molecular mechanism and glomerular cell crosstalk by which local upregulation of MIF and its receptor complex CD74/CD44 mediate glomerular injury and pathologic proliferation in GN. PMID:26453615

Quantitative investigation of physical factors contributing to gold nanoparticle-mediated proton dose enhancement

International Nuclear Information System (INIS)

Cho, Jongmin; Manohar, Nivedh; Kerr, Matthew; Cho, Sang Hyun; Gonzalez-Lepera, Carlos; Krishnan, Sunil

2016-01-01

Some investigators have shown tumor cell killing enhancement in vitro and tumor regression in mice associated with the loading of gold nanoparticles (GNPs) before proton treatments. Several Monte Carlo (MC) investigations have also demonstrated GNP-mediated proton dose enhancement. However, further studies need to be done to quantify the individual physical factors that contribute to the dose enhancement or cell-kill enhancement (or radiosensitization). Thus, the current study investigated the contributions of particle-induced x-ray emission (PIXE), particle-induced gamma-ray emission (PIGE), Auger and secondary electrons, and activation products towards the total dose enhancement. Specifically, GNP-mediated dose enhancement was measured using strips of radiochromic film that were inserted into vials of cylindrical GNPs, i.e. gold nanorods (GNRs), dispersed in a saline solution (0.3 mg of GNRs/g or 0.03% of GNRs by weight), as well as vials containing water only, before proton irradiation. MC simulations were also performed with the tool for particle simulation code using the film measurement setup. Additionally, a high-purity germanium detector system was used to measure the photon spectrum originating from activation products created from the interaction of protons and spherical GNPs present in a saline solution (20 mg of GNPs/g or 2% of GNPs by weight). The dose enhancement due to PIXE/PIGE recorded on the films in the GNR-loaded saline solution was less than the experimental uncertainty of the film dosimetry (<2%). MC simulations showed highly localized dose enhancement (up to a factor 17) in the immediate vicinity (<100 nm) of GNRs, compared with hypothetical water nanorods (WNRs), mostly due to GNR-originated Auger/secondary electrons; however, the average dose enhancement over the entire GNR-loaded vial was found to be minimal (0.1%). The dose enhancement due to the activation products from GNPs was minimal (<0.1%) as well. In conclusion, under the

$\\delta$-Expansion at Finite Temperature

OpenAIRE

Ramos, Rudnei O.

1996-01-01

We apply the $\\delta$-expansion perturbation scheme to the $\\lambda \\phi^{4}$ self-interacting scalar field theory in 3+1 D at finite temperature. In the $\\delta$-expansion the interaction term is written as $\\lambda (\\phi^{2})^{ 1 + \\delta}$ and $\\delta$ is considered as the perturbation parameter. We compute within this perturbative approach the renormalized mass at finite temperature at a finite order in $\\delta$. The results are compared with the usual loop-expansion at finite temperature.

Occupational exposure to ionizing radiation as a risk factor for free-radicals mediated diseases

International Nuclear Information System (INIS)

Djurovic, B.; Spasic-Jokic, V.; Selakovic, V.

2007-01-01

Complete text of publication follows. It was experimentally showed, that the exposure to low doses of ionizing radiation (IR) result in over-production of oxygen derived free radicals with inverse dose-rate effect. The oxidative stress that follows, especially cell membrane damage, was considered by Petkau, as crucial step in the induction of radiation injuries. From clinical research and practice with other unexposed patients is known that this type of cell damage can lead to an impairment of cellular function and can cause many free-radicals mediated diseases, such as atherosclerosis, damage of heart muscles, inflammatory and immuno-reactive lesions, senile dementia, cancer, etc. The aim of this paper is to investigate if occupational exposure to low doses of IR change the redox status of exposed personnel, and if so, is it the additional risk factor for free-radicals mediated diseases. Subjects: 77 medical workers, devided in two groups: 44 occupationally exposed to ionizing radiation (E), and 33 controls (C), matched in age, gender, habits-daitary, alcohol consumption, smoking and exposure time, were examined. Methods: Radiation dose accumulated over years was calculated on the basis of individual TL-dose records. Superoxide-anion and MDA production, as well as SOD (MnSOD, CuZnSOD) and GSH activity were determined in blood samples spectrophotometrically. Results: Significantly higher incidence of cataract, and higher, but not significant, incidence of cardiovascular diseases was noticed in exposed. Our results also confirmed significantly higher superoxide and MDA production (p=0.0049, 0.000028, respectively), as well as, increased activity of MnSOD and CuZnSOD (p0.0105, 0.001, respectively), and decreased level of GSH (p=0.0599) in exposed. Conclusions: Our results showed that low doses of IR could induce oxidative stress and for that reason could be considered as additional risk factor for free radical-mediated diseases. Further epidemiological studies are

Pathways between acculturation and health behaviors among residents of low-income housing: the mediating role of social and contextual factors.

Science.gov (United States)

Allen, Jennifer Dacey; Caspi, Caitlin; Yang, May; Leyva, Bryan; Stoddard, Anne M; Tamers, Sara; Tucker-Seeley, Reginald D; Sorensen, Glorian C

2014-12-01

Acculturation may influence health behaviors, yet mechanisms underlying its effect are not well understood. In this study, we describe relationships between acculturation and health behaviors among low-income housing residents, and examine whether these relationships are mediated by social and contextual factors. Residents of 20 low-income housing sites in the Boston metropolitan area completed surveys that assessed acculturative characteristics, social/contextual factors, and health behaviors. A composite acculturation scale was developed using latent class analysis, resulting in four distinct acculturative groups. Path analysis was used to examine interrelationships between acculturation, health behaviors, and social/contextual factors, specifically self-reported social ties, social support, stress, material hardship, and discrimination. Of the 828 respondents, 69% were born outside of the U.S. Less acculturated groups exhibited healthier dietary practices and were less likely to smoke than more acculturated groups. Acculturation had a direct effect on diet and smoking, but not physical activity. Acculturation also showed an indirect effect on diet through its relationship with material hardship. Our finding that material hardship mediated the relationship between acculturation and diet suggests the need to explicate the significant role of financial resources in interventions seeking to promote healthy diets among low-income immigrant groups. Future research should examine these social and contextual mediators using larger, population-based samples, preferably with longitudinal data. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Fibroblast Growth Factor 21 Mediates Glycemic Regulation by Hepatic JNK

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Santiago Vernia

2016-03-01

Full Text Available The cJun NH2-terminal kinase (JNK-signaling pathway is implicated in metabolic syndrome, including dysregulated blood glucose concentration and insulin resistance. Fibroblast growth factor 21 (FGF21 is a target of the hepatic JNK-signaling pathway and may contribute to the regulation of glycemia. To test the role of FGF21, we established mice with selective ablation of the Fgf21 gene in hepatocytes. FGF21 deficiency in the liver caused marked loss of FGF21 protein circulating in the blood. Moreover, the protective effects of hepatic JNK deficiency to suppress metabolic syndrome in high-fat diet-fed mice were not observed in mice with hepatocyte-specific FGF21 deficiency, including reduced blood glucose concentration and reduced intolerance to glucose and insulin. Furthermore, we show that JNK contributes to the regulation of hepatic FGF21 expression during fasting/feeding cycles. These data demonstrate that the hepatokine FGF21 is a key mediator of JNK-regulated metabolic syndrome.

Electrical Resistance Alloys and Low-Expansion Alloys

DEFF Research Database (Denmark)

Kjer, Torben

1996-01-01

The article gives an overview of electrical resistance alloys and alloys with low thermal expansion. The electrical resistance alloys comprise resistance alloys, heating alloys and thermostat alloys. The low expansion alloys comprise alloys with very low expansion coefficients, alloys with very low...... thermoelastic coefficients and age hardenable low expansion alloys....

Coded-Wire Tag Expansion Factors for Chinook Salmon Carcass Surveys in California: Estimating the Numbers and Proportions of Hatchery-Origin Fish

Directory of Open Access Journals (Sweden)

Michael S. Mohr

2013-12-01

Full Text Available Recovery of fish with adipose fin clips (adc and coded-wire tags (cwt in escapement surveys allows calculation of expansion factors used in estimation of the total number of fish from each adc,cwt release group, allowing escapement to be resolved by age and stock of origin. Expanded recoveries are used to derive important estimates such as the total number and proportion of hatchery-origin fish present. The standard estimation scheme assumes accurate visual classification of adc status, which can be problematic for decomposing carcasses. Failure to account for this potential misclassification can lead to significant estimation bias. We reviewed sample expansion factors used for the California Central Valley Chinook salmon 2010 carcass surveys in this context. For upper Sacramento River fall-run and late fall-run carcass surveys, the estimated proportions of adc,cwt fish for fresh and non-fresh carcasses differed substantially, likely from the under-recognition of adc fish in non-fresh carcasses. The resulting estimated proportions of hatchery-origin fish in the upper Sacramento River fall-run and late fall-run carcass surveys were 2.33 to 2.89 times higher if only fresh carcasses are considered. Similar biases can be avoided by consideration of only fresh carcasses for which determination of adc status is relatively straightforward; however, restricting the analysis entirely to fresh carcasses may limit precision because of reduced sample size, and is only possible if protocols for sampling and recording data ensure that the sample data and results for fresh carcasses can be extracted. Thus we recommend sampling protocols that are clearly documented and separately track fresh versus non-fresh carcasses, either collecting only definitively adc fish or that carefully track non-fresh carcasses that are definitively adc versus those that are possibly adc. This would allow judicious use of non-fresh carcass data when sample sizes are otherwise

Disjoint sum expansion method in FTA

International Nuclear Information System (INIS)

Ruan Keqiang

1987-01-01

An expansion formula for transforming boolean algebraic expressions into disjoint form was proved. Based on this expansion formula, a method for transforming system failure function into disjoint form was devised. The fact that the expansion can be done for several elements simulatneously makes the method flexible and fast. Some examples from fault tree analysis (FTA) and network analysis were examined by the new method to show its algorithm and its merit. Besides, by means of the proved expansion formula some boolean algebraic relations can proved very easily

Maxwell superalgebras and Abelian semigroup expansion

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P.K. Concha

2014-09-01

Full Text Available The Abelian semigroup expansion is a powerful and simple method to derive new Lie algebras from a given one. Recently it was shown that the S-expansion of so(3,2 leads us to the Maxwell algebra M. In this paper we extend this result to superalgebras, by proving that different choices of abelian semigroups S lead to interesting D=4 Maxwell Superalgebras. In particular, the minimal Maxwell superalgebra sM and the N-extended Maxwell superalgebra sM(N recently found by the Maurer–Cartan expansion procedure, are derived alternatively as an S-expansion of osp(4|N. Moreover, we show that new minimal Maxwell superalgebras type sMm+2 and their N-extended generalization can be obtained using the S-expansion procedure.

Maxwell superalgebras and Abelian semigroup expansion

Energy Technology Data Exchange (ETDEWEB)

Concha, P.K.; Rodríguez, E.K. [Departamento de Física, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Dipartimento di Scienza Applicata e Tecnologia (DISAT), Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino (Italy); Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Torino, Via Pietro Giuria, 1, 10125 Torino (Italy)

2014-09-15

The Abelian semigroup expansion is a powerful and simple method to derive new Lie algebras from a given one. Recently it was shown that the S-expansion of so(3,2) leads us to the Maxwell algebra M. In this paper we extend this result to superalgebras, by proving that different choices of abelian semigroups S lead to interesting D=4 Maxwell Superalgebras. In particular, the minimal Maxwell superalgebra sM and the N-extended Maxwell superalgebra sM{sup (N)} recently found by the Maurer–Cartan expansion procedure, are derived alternatively as an S-expansion of osp(4|N). Moreover, we show that new minimal Maxwell superalgebras type sM{sub m+2} and their N-extended generalization can be obtained using the S-expansion procedure.

Influence of anodization parameters on the volume expansion of anodic aluminum oxide formed in mixed solution of phosphoric and oxalic acids

Science.gov (United States)

Kao, Tzung-Ta; Chang, Yao-Chung

2014-01-01

The growth of anodic alumina oxide was conducted in the mixed solution of phosphoric and oxalic acids. The influence of anodizing voltage, electrolyte temperature, and concentration of phosphoric and oxalic acids on the volume expansion of anodic aluminum oxide has been investigated. Either anodizing parameter is chosen to its full extent of range that allows the anodization process to be conducted without electric breakdown and to explore the highest possible volume expansion factor. The volume expansion factors were found to vary between 1.25 and 1.9 depending on the anodizing parameters. The variation is explained in connection with electric field, ion transport number, temperature effect, concentration, and activity of acids. The formation of anodic porous alumina at anodizing voltage 160 V in 1.1 M phosphoric acid mixed with 0.14 M oxalic acid at 2 °C showed the peak volume expansion factor of 1.9 and the corresponding moderate growth rate of 168 nm/min.

Extra-chromosomal DNA maintenance in Bacillus subtilis, dependence on flagellation factor FliF and moonlighting mediator EdmS.

Science.gov (United States)

Hakumai, Yuichi; Shimomoto, Kouko; Ashiuchi, Makoto

2015-05-15

Extra-chromosomal DNA maintenance (EDM) as an important process in the propagation and genetic engineering of microbes. Bacillus subtilis EdmS (formerly PgsE), a protein comprising 55 amino acids, is a mediator of the EDM process. In this study, the effect of mutation of global regulators on B. subtilis EDM was examined. Mutation of the swrA gene abolished EdmS-mediated EDM. It is known that swrA predominantly regulates expression of the fla/che operon in B. subtilis. We therefore performed EDM analysis using fla/che-deletion mutants and identified an EDM-mediated EDM cooperator in the flgB-fliL region. Further genetic investigation identified the flagellation factor FliF is a crucial EDM cooperator. To our knowledge, this is the first observation of the moonlighting function of FliF in DNA maintenance. Copyright © 2015 Elsevier Inc. All rights reserved.

HIV-1 Tat C-mediated regulation of tumor necrosis factor receptor-associated factor-3 by microRNA 32 in human microglia

Directory of Open Access Journals (Sweden)

Mishra Ritu

2012-06-01

Full Text Available Abstract Background HIV-1 Tat protein is known to be associated with neuroinflammation, a condition that develops in almost half of patients infected with HIV-1. HIV-1 Tat can alter glial neuroprotective functions, leading to neurotoxicity within the CNS. HIV-1 Tat is known to be secreted from productively infected cells and can affect neighboring uninfected cells by modulating cellular gene expression in a bystander fashion. Methods We were interested to study whether exogenous exposure to HIV-1 Tat-C protein perturbs the microRNA (miRNA expression profile of human microglial cells, leading to altered protein expression. We used protein expression and purification, miRNA overexpression, miRNA knockdown, transfection, site-directed mutagenesis, real-time PCR, luciferase assay and western blotting techniques to perform our study. Results HIV-1 Tat-C treatment of human microglial cells resulted in a dose-dependent increase in miR-32 expression. We found that tumor necrosis factor-receptor–associated factor 3 TRAF3 is a direct target for miR-32, and overexpression of miR-32 in CHME3 cells decreased TRAF3 both at the mRNA and the protein level. Recovery of TRAF3 protein expression after transfection of anti-miR-32 and the results of the luciferase reporter assay provided direct evidence of TRAF3 regulation by miR-32. We found that the regulation of interferon regulatory factor 3 (IRF3 and IRF7 is controlled by cellular levels of TRAF3 protein in microglial cells, as after overexpression of miR-32 and application of anti-miR-32, expression levels of IRF3 and IRF7 were inversely regulated by expression levels of TRAF3. Thus, our results suggest a novel miRNA mediated mechanism for regulation of TRAF3 in human microglial cells exposed to HIV-1 Tat C protein. These results may help to elucidate the detrimental neuroinflammatory consequences of HIV-1 Tat C protein in bystander fashion. Conclusion HIV-1 Tat protein can modulate TRAF3 expression through

Rose bush leaf and internode expansion dynamics: analysis and development of a model capturing interplant variability

Directory of Open Access Journals (Sweden)

Sabine eDemotes-Mainard

2013-10-01

Full Text Available Bush rose architecture, among other factors, such as plant health, determines plant visual quality. The commercial product is the individual plant and interplant variability may be high within a crop. Thus, both mean plant architecture and interplant variability should be studied. Expansion is an important feature of architecture, but it has been little studied at the level of individual organs in bush roses. We investigated the expansion kinetics of primary shoot organs, to develop a model reproducing the organ expansion of real crops from non destructive input variables. We took interplant variability in expansion kinetics and the model’s ability to simulate this variability into account. Changes in leaflet and internode dimensions over thermal time were recorded for primary shoot expansion, on 83 plants from three crops grown in different climatic conditions and densities. An empirical model was developed, to reproduce organ expansion kinetics for individual plants of a real crop of bush rose primary shoots. Leaflet or internode length was simulated as a logistic function of thermal time. The model was evaluated by cross-validation. We found that differences in leaflet or internode expansion kinetics between phytomer positions and between plants at a given phytomer position were due mostly to large differences in time of organ expansion and expansion rate, rather than differences in expansion duration. Thus, in the model, the parameters linked to expansion duration were predicted by values common to all plants, whereas variability in final size and organ expansion time was captured by input data. The model accurately simulated leaflet and internode expansion for individual plants (RMSEP = 7.3% and 10.2% of final length, respectively. Thus, this study defines the measurements required to simulate expansion and provides the first model simulating organ expansion in rosebush to capture interplant variability.

Explaining Gender Gaps in English Composition and College Algebra in College: The Mediating Role of Psychosocial Factors

Science.gov (United States)

Ndum, Edwin; Allen, Jeff; Way, Jason; Casillas, Alex

2018-01-01

We examined the role of six psychosocial factors (PSFs) in explaining gender gaps in English Composition (n = 8,633) and College Algebra (n = 2,261) using data of first-year female (55%) and male students from 42 colleges. Using a multilevel model and controlling for prior achievement, we found that PSFs mediated between 3% and 41% of the gender…

Spatiotemporal Variation of Driving Forces for Settlement Expansion in Different Types of Counties

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Guanglong Dong

2015-12-01

Full Text Available Understanding the process of settlement expansion and the spatiotemporal variation of driving forces is the foundation of rational and specific planning for sustainable development. However, little attention has been paid to the spatiotemporal differences of driving forces among different counties, especially when they are representatives of different development types. This study used Guanyun, Kunshan and Changshu as case studies, and binary logistic regression was employed. The results showed that the expansion rates of Kunshan and Changshu were 5.55 and 3.93 times higher than that of Guanyun. The combinations and relative importance of drivers varied with counties and periods. The change in the number of driving forces can be divided into three stages: increasing stage, decreasing stage, and stable stage. In the relatively developed counties, Kunshan and Changshu, the importance of population is decreased, while it remain an important factor in the less developed county, Guanyun. In addition, the effect of GDP stays the same in Kunshan while it becomes the most important factor in Changshu. The distance to the main road and the distance to town are increasingly important in Kunshan and Guanyun, and distance to town has been the only common factor in the last period, indicating the discrepancy is increased. The relative importance of distance to a lake in Kunshan and Changshu increased, reflecting the role of increasing tourism in accelerating settlement expansion.

Uniform gradient expansions

CERN Document Server

Giovannini, Massimo

2015-01-01

Cosmological singularities are often discussed by means of a gradient expansion that can also describe, during a quasi-de Sitter phase, the progressive suppression of curvature inhomogeneities. While the inflationary event horizon is being formed the two mentioned regimes coexist and a uniform expansion can be conceived and applied to the evolution of spatial gradients across the protoinflationary boundary. It is argued that conventional arguments addressing the preinflationary initial conditions are necessary but generally not sufficient to guarantee a homogeneous onset of the conventional inflationary stage.

Using nodal expansion method in calculation of reactor core with square fuel assemblies

International Nuclear Information System (INIS)

Abdollahzadeh, M. Y.; Boroushaki, M.

2009-01-01

A polynomial nodal method is developed to solve few-group neutron diffusion equations in cartesian geometry. In this article, the effective multiplication factor, group flux and power distribution based on the nodal polynomial expansion procedure is presented. In addition, by comparison of the results the superiority of nodal expansion method on finite-difference and finite-element are fully demonstrated. The comparison of the results obtained by these method with those of the well known benchmark problems have shown that they are in very good agreement.

The Schizosaccharomyces pombe Mediator

DEFF Research Database (Denmark)

Venturi, Michela

, Schizosaccharomyces pombe and mammalian Mediator. In our study, we have taken the S. pombe Mediator into consideration and characterized genetically and biochemically two subunits already know in S. cerevisiae, Med9 and Med11, but still not identified in the S. pombe Mediator. Genetic analysis has shown that med9......In the past several years great attention has been dedicated to the characterization of the Mediator complex in a different range of model organisms. Mediator is a conserved co-activator complex involved in transcriptional regulation and it conveys signals from regulatory transcription factors...... to the basal transcription machinery. Mediator was initially isolated from Saccharomyces cerevisiae based on its ability to render a RNA polymerase II in vitro transcription system responsive to activators. Additionally, structural studies have revealed striking structural similarities between S. cerevisiae...

Thin foil expansion into a vacuum

International Nuclear Information System (INIS)

Mora, P.

2005-01-01

Plasma expansion into a vacuum is an old problem which has been renewed recently in various contexts: expansion of ultra-cold plasmas, cluster expansion, of dust grains, expansion of thin foils. In this presentation I will first discuss the physics of the expansion of a thin foil irradiated by an ultra-short ultra-intense laser pulse. The expansion results in the formation of high energy ions. For an infinitely steep plasma-vacuum interface the fastest ions are located in the outer part of the expansion and their velocity is given by ν m ax∼ 2 C s (In ω p it) where c s (Zk B T e /m i )''1/2 is the ion-acoustic velocity ω p i=(n e 0Ze''2/m i e 0 )''1/2 is the ion plasma frequency, n e 0 is the electron density in the unperturbed plasma, Z is the ion charge number. In the above expression, t is either the pulse duration or the effective acceleration time (in particular t∼L/2c s , where L is the width of the foil, when the electron cooling is taken into account). A salient characteristic of the expansion is the occurrence of a double layer structure and a peak of the accelerating electric field at the ion front. I will explain the origin of the peak and predict its temporal behavior. This peak has been diagnosed in recent experiments. I will also discuss the effect of a 2-temperatures electron distribution function on the expansion, showing the dominant role of the hot electron component. Finally I will discuss the occurrence of ion spikes in the expansion when the initial density profile is smooth. The ion spike is due to a wave breaking which cannot be handled in a satisfactory way by a fluid code and requires a kinetic description. A. simple collisionless particle code has been used to treat the evolution of the spike after the wave breaking and the results will be shown. (Author)

Thermal expansion of superconducting fulleride and borocarbide compounds

International Nuclear Information System (INIS)

Burkhart, G.J.

1995-08-01

In order to detact and analyze thermodynamic phase transitions, the investigation of the thermal expansion via capacitance dilatometry is a powerful experimental technique, due to the extremely high resolution (ΔL/L∝10 -8 -10 -10 ). With respect to the air sensitivity of the fullerides a dilatometer operating under inert atmosphere was designed and the thermal expansion of polycrystalline fulleride (Rb 3 C 60 , K 3 C 60 ) and borocarbide (YNi 2 B 2 C, LuNi 2 B 2 C) compounds was determined in the temperature range 5-320 K. Most effort was focused on a quantitative evaluation of the discontinuity in the thermal expansivity α at the superconducting transition. The results are discussed in the context of the Ehrenfest relation, which connects the jump in the thermal expansivity Δα with the pressure dependence of the superconducting transition temperature dT c /dp and the jump in the specific heat Δc p /T c at the superconducting transition. For Rb 3 C 60 and K 3 C 60 the jump in the specific heat can be derived via the Ehrenfest relation using the results of the thermal expansion measurements and the well-known pressure dependence of the superconducting transition temperature. The derived values for Rb 3 C 60 and K 3 Cu 60 are Δc p /T c ∝75mJ/molK 2 and Δc p /T c ∝64 mJ.molK 2 , respectively. The directly measured specific heat jump of K 3 C 60 gives approximately the same value of Δc p /T c , and, therefore, the use of the Ehrenfest relation on fullerides is justified. The specific heat jumps Δc p /T c , determined from theoretically derived values of the density of states at the Fermi level N(E F ) and the McMillan-parameter λ, exceed the experimental results by a factor of 1.5-2. This finding reflects the uncertainty concerning the superconducting parameters N(E F ) and λ. (orig.)

[Unconscious sexual desire: fMRI and EEG evidences from self-expansion theory to mirror neurons].

Science.gov (United States)

Ortigue, Stephanie; Bianchi-Demicheli, Francesco

2010-03-24

Recent advances in cognitive-social neuroscience allow a better understanding of the mechanisms underlying dyadic relationships. From a neuronal viewpoint, desire in dyadic relationships involves a specific fronto-temporo-parietal network and also a subcortical network that mediates conscious and unconscious mechanisms of reward, satisfaction, attention, self representation and self-expansion. The integration of this neuroscientific knowledge on the unconscious neurobiological activation for sexual desire in the human brain will provide physicians with new therapeutical and neuroscientific tools to apprehend sexual disorders in couple.

The rate of beneficial mutations surfing on the wave of a range expansion.

Directory of Open Access Journals (Sweden)

Rémi Lehe

Full Text Available Many theoretical and experimental studies suggest that range expansions can have severe consequences for the gene pool of the expanding population. Due to strongly enhanced genetic drift at the advancing frontier, neutral and weakly deleterious mutations can reach large frequencies in the newly colonized regions, as if they were surfing the front of the range expansion. These findings raise the question of how frequently beneficial mutations successfully surf at shifting range margins, thereby promoting adaptation towards a range-expansion phenotype. Here, we use individual-based simulations to study the surfing statistics of recurrent beneficial mutations on wave-like range expansions in linear habitats. We show that the rate of surfing depends on two strongly antagonistic factors, the probability of surfing given the spatial location of a novel mutation and the rate of occurrence of mutations at that location. The surfing probability strongly increases towards the tip of the wave. Novel mutations are unlikely to surf unless they enjoy a spatial head start compared to the bulk of the population. The needed head start is shown to be proportional to the inverse fitness of the mutant type, and only weakly dependent on the carrying capacity. The precise location dependence of surfing probabilities is derived from the non-extinction probability of a branching process within a moving field of growth rates. The second factor is the mutation occurrence which strongly decreases towards the tip of the wave. Thus, most successful mutations arise at an intermediate position in the front of the wave. We present an analytic theory for the tradeoff between these factors that allows to predict how frequently substitutions by beneficial mutations occur at invasion fronts. We find that small amounts of genetic drift increase the fixation rate of beneficial mutations at the advancing front, and thus could be important for adaptation during species invasions.

The Thermal Expansion Of Feldspars

Science.gov (United States)

Hovis, G. L.; Medford, A.; Conlon, M.

2009-12-01

Hovis and others (1) investigated the thermal expansion of natural and synthetic AlSi3 feldspars and demonstrated that the coefficient of thermal expansion (α) decreases significantly, and linearly, with increasing room-temperature volume (VRT). In all such feldspars, therefore, chemical expansion limits thermal expansion. The scope of this work now has been broadened to include plagioclase and Ba-K feldspar crystalline solutions. X-ray powder diffraction data have been collected between room temperature and 925 °C on six plagioclase specimens ranging in composition from anorthite to oligoclase. When combined with thermal expansion data for albite (2,3,4) a steep linear trend of α as a function of VRT emerges, reflecting how small changes in composition dramatically affect expansion behavior. The thermal expansion data for five synthetic Ba-K feldspars ranging in composition from 20 to 100 mole percent celsian, combined with data for pure K-feldspar (3,4), show α-VRT relationships similar in nature to the plagioclase series, but with a slope and intercept different from the latter. Taken as a group all Al2Si2 feldspars, including anorthite and celsian from the present study along with Sr- (5) and Pb-feldspar (6) from other workers, show very limited thermal expansion that, unlike AlSi3 feldspars, has little dependence on the divalent-ion (or M-) site occupant. This apparently is due to the necessitated alternation of Al and Si in the tetrahedral sites of these minerals (7), which in turn locks the tetrahedral framework and makes the M-site occupant nearly irrelevant to expansion behavior. Indeed, in feldspar series with coupled chemical substitution it is the change away from a 1:1 Al:Si ratio that gives feldspars greater freedom to expand. Overall, the relationships among α, chemical composition, and room-temperature volume provide useful predictive tools for estimating feldspar thermal expansion and give insight into the controls of expansion behavior in

The Effects of State Medicaid Expansion on Low-Income Individuals' Access to Health Care: Multilevel Modeling.

Science.gov (United States)

Choi, Sunha; Lee, Sungkyu; Matejkowski, Jason

2018-06-01

This study aimed to examine how states' Medicaid expansion affected insurance status and access to health care among low-income expansion state residents in 2015, the second year of the expansion. Data from the 2012 and 2015 Behavioral Risk Factor Surveillance System were linked to state-level data. A nationally representative sample of 544,307 adults (ages 26-64 years) from 50 states and Washington, DC were analyzed using multilevel modeling. The results indicate substantial increases in health care access between 2012 and 2015 among low-income adults in Medicaid expansion states. The final conditional multilevel models with low-income adults who had income at or below 138% of the poverty line indicate that, after controlling for individual- and state-level covariates, those who resided in the Medicaid expansion states were more likely to have health insurance (OR = 1.97, P income residents in non-expansion states in 2015. Moreover, the significant interaction terms indicate that adults living in non-expansion states with income below 100% of the poverty line are the most vulnerable compared with their counterparts in expansion states and with those with income between 100%-138% of the poverty line. This study demonstrates that state-level Medicaid expansion improved health care access among low-income US residents. However, residents with income below 100% of the poverty line in non-expansion states were disproportionately negatively affected by states' decision to not expand Medicaid coverage.

Thermal expansion of L-ascorbic acid

Science.gov (United States)

Nicolaï, B.; Barrio, M.; Tamarit, J.-Ll.; Céolin, R.; Rietveld, I. B.

2017-04-01

The specific volume of vitamin C has been investigated by X-ray powder diffraction as a function of temperature from 110 K up to complete degradation around 440 K. Its thermal expansion is relatively small in comparison with other organic compounds with an expansivity α v of 1.2(3) × 10-4 K-1. The structure consists of strongly bound molecules in the ac plane through a dense network of hydrogen bonds. The thermal expansion is anisotropic. Along the b axis, the expansion has most leeway and is about 10 times larger than in the other directions.

Chemical graph-theoretic cluster expansions

International Nuclear Information System (INIS)

Klein, D.J.

1986-01-01

A general computationally amenable chemico-graph-theoretic cluster expansion method is suggested as a paradigm for incorporation of chemical structure concepts in a systematic manner. The cluster expansion approach is presented in a formalism general enough to cover a variety of empirical, semiempirical, and even ab initio applications. Formally such approaches for the utilization of chemical structure-related concepts may be viewed as discrete analogues of Taylor series expansions. The efficacy of the chemical structure concepts then is simply bound up in the rate of convergence of the cluster expansions. In many empirical applications, e.g., boiling points, chromatographic separation coefficients, and biological activities, this rate of convergence has been observed to be quite rapid. More note will be made here of quantum chemical applications. Relations to questions concerning size extensivity of energies and size consistency of wave functions are addressed

Defining chemical expansion: the choice of units for the stoichiometric expansion coefficient

DEFF Research Database (Denmark)

Marrocchelli, Dario; Chatzichristodoulou, Christodoulos; Bishop, Sean R.

2014-01-01

Chemical expansion refers to the spatial dilation of a material that occurs upon changes in its composition. When this dilation is caused by a gradual, iso-structural increase in the lattice parameter with composition, it is related to the composition change by the stoichiometric expansion coeffi...... are provided for changes in oxygen content in fluorite, perovskite, and Ruddlesden-Popper (K2NiF4) phase materials used in solid oxide fuel cells....

Function and regulation of the Mediator complex.

Science.gov (United States)

Conaway, Ronald C; Conaway, Joan Weliky

2011-04-01

Over the past few years, advances in biochemical and genetic studies of the structure and function of the Mediator complex have shed new light on its subunit architecture and its mechanism of action in transcription by RNA polymerase II (pol II). The development of improved methods for reconstitution of recombinant Mediator subassemblies is enabling more in-depth analyses of basic features of the mechanisms by which Mediator interacts with and controls the activity of pol II and the general initiation factors. The discovery and characterization of multiple, functionally distinct forms of Mediator characterized by the presence or absence of the Cdk8 kinase module have led to new insights into how Mediator functions in both Pol II transcription activation and repression. Finally, progress in studies of the mechanisms by which the transcriptional activation domains (ADs) of DNA binding transcription factors target Mediator have brought to light unexpected complexities in the way Mediator participates in signal transduction. Copyright © 2011 Elsevier Ltd. All rights reserved.

Special ways of knowing in science: expansive learning opportunities with bilingual children with learning disabilities

Science.gov (United States)

Martínez-Álvarez, Patricia

2017-09-01

The field of bilingual special education is currently plagued with contradictions resulting in a serious underrepresentation of emergent bilinguals with learning disabilities in professional science fields. This underrepresentation is due in large part to the fact that educational systems around the world are inadequately prepared to address the educational needs of these children; this inadequacy is rooted in a lack of understanding of the linguistic and cultural factors impacting learning. Accepting such a premise and assuming that children learn in unexpected ways when instructional practices attend to culture and language, this study documents a place-based learning experience integrating geoscience and literacy in a fourth-grade dual language classroom. Data sources include transcribed audio-taped conversations from learning experience sessions and interviews that took place as six focus children, who had been identified as having specific learning disabilities, read published science texts (i.e. texts unaltered linguistically or conceptually to meet the needs of the readers). My analysis revealed that participants generated responses that were often unexpected if solely analyzed from those Western scientific perspectives traditionally valued in school contexts. However, these responses were also full of purposeful and rich understandings that revealed opportunities for expansive learning. Adopting a cultural historical activity theory perspective, instructional tools such as texts, visuals, and questions were found to act as mediators impacting the learning in both activity systems: (a) teacher- researcher learning from children, and (b) children learning from teachers. I conclude by suggesting that there is a need to understand students' ways of knowing to their full complexity, and to deliberately recognize teachers as learners, researchers, and means to expansive learning patterns that span beyond traditional learning boundaries.

Edgeworth expansion for functionals of continuous diffusion processes

DEFF Research Database (Denmark)

Podolskij, Mark; Yoshida, Nakahiro

This paper presents new results on the Edgeworth expansion for high frequency functionals of continuous diffusion processes. We derive asymptotic expansions for weighted functionals of the Brownian motion and apply them to provide the Edgeworth expansion for power variation of diffusion processes....... Our methodology relies on martingale embedding, Malliavin calculus and stable central limit theorems for semimartingales. Finally, we demonstrate the density expansion for studentized statistics of power variations.......This paper presents new results on the Edgeworth expansion for high frequency functionals of continuous diffusion processes. We derive asymptotic expansions for weighted functionals of the Brownian motion and apply them to provide the Edgeworth expansion for power variation of diffusion processes...

Angiopoietin-like protein 3 promotes preservation of stemness during ex vivo expansion of murine hematopoietic stem cells.

Science.gov (United States)

Farahbakhshian, Elnaz; Verstegen, Monique M; Visser, Trudi P; Kheradmandkia, Sima; Geerts, Dirk; Arshad, Shazia; Riaz, Noveen; Grosveld, Frank; van Til, Niek P; Meijerink, Jules P P

2014-01-01

Allogeneic hematopoietic stem cell (HSC) transplantations from umbilical cord blood or autologous HSCs for gene therapy purposes are hampered by limited number of stem cells. To test the ability to expand HSCs in vitro prior to transplantation, two growth factor cocktails containing stem cell factor, thrombopoietin, fms-related tyrosine kinase-3 ligand (STF) or stem cell factor, thrombopoietin, insulin-like growth factor-2, fibroblast growth factor-1 (STIF) either with or without the addition of angiopoietin-like protein-3 (Angptl3) were used. Culturing HSCs in STF and STIF media for 7 days expanded long-term repopulating stem cells content in vivo by ∼6-fold and ∼10-fold compared to freshly isolated stem cells. Addition of Angptl3 resulted in increased expansion of these populations by ∼17-fold and ∼32-fold, respectively, and was further supported by enforced expression of Angptl3 in HSCs through lentiviral transduction that also promoted HSC expansion. As expansion of highly purified lineage-negative, Sca-1+, c-Kit+ HSCs was less efficient than less pure lineage-negative HSCs, Angptl3 may have a direct effect on HCS but also an indirect effect on accessory cells that support HSC expansion. No evidence for leukemia or toxicity was found during long-term follow up of mice transplanted with ex vivo expanded HSCs or manipulated HSC populations that expressed Angptl3. We conclude that the cytokine combinations used in this study to expand HSCs ex vivo enhances the engraftment in vivo. This has important implications for allogeneic umbilical cord-blood derived HSC transplantations and autologous HSC applications including gene therapy.

β-expansion attractors observed in A/D converters

Science.gov (United States)

Kohda, Tohru; Horio, Yoshihiko; Aihara, Kazuyuki

2012-12-01

The recently proposed β-encoders, analog-to-digital converters using an amplifier with a factor β and a flaky quantizer with threshold ν, have proven to be explained by the deterministic dynamics of multi-valued Rényi-Parry maps. Such a map is locally eventually onto [ν-1, ν), which is topologically conjugate to Parry's (β,α)-map with α =(β-1)(ν-1). This implies that β-encoders have a closed subinterval [ν-1,ν), which includes an attractor. Thus, the iteration of the multi-valued Rényi-Parry map performs the β-expansion of x while quantization errors in β-encoders behave chaotically and do not converge to a fixed point. This β-expansion attractor is relatively simpler than previously reported attractors. The object of this paper is twofold: to observe the embedded attractors in the β-encoder and to identify attractors that are useful for spread-spectrum codes and optimization techniques using pseudo-random numbers.

Expansion of the invasive dwarf eelgrass, Zostera japonica, in Yaquina Bay, Oregon

Science.gov (United States)

The areal coverage of the non-indigenous dwarf eelgrass, Zostera japonica, is increasing in several estuaries on the US West Coast. As a result, regulatory agencies in the states of California and Washington are considering methods of controlling its expansion. Factors relevan...

Expansion lyre-shaped tube

International Nuclear Information System (INIS)

Andro, Jean.

1973-01-01

The invention relates the expansion lyre-shaped tube portions formed in dudgeoned tubular bundles between two bottom plates. An expansion lyre comprises at least two sets of tubes of unequal lengths coplanar and symmetrical with respect to the main tube axis, with connecting portions between the tubes forming said sets. The invention applies to apparatus such as heat exchangers, heaters, superheaters or breeders [fr

An evolutionary analysis of genome expansion and pathogenicity in Escherichia coli.

Science.gov (United States)

Bohlin, Jon; Brynildsrud, Ola B; Sekse, Camilla; Snipen, Lars

2014-10-09

There are several studies describing loss of genes through reductive evolution in microbes, but how selective forces are associated with genome expansion due to horizontal gene transfer (HGT) has not received similar attention. The aim of this study was therefore to examine how selective pressures influence genome expansion in 53 fully sequenced and assembled Escherichia coli strains. We also explored potential connections between genome expansion and the attainment of virulence factors. This was performed using estimations of several genomic parameters such as AT content, genomic drift (measured using relative entropy), genome size and estimated HGT size, which were subsequently compared to analogous parameters computed from the core genome consisting of 1729 genes common to the 53 E. coli strains. Moreover, we analyzed how selective pressures (quantified using relative entropy and dN/dS), acting on the E. coli core genome, influenced lineage and phylogroup formation. Hierarchical clustering of dS and dN estimations from the E. coli core genome resulted in phylogenetic trees with topologies in agreement with known E. coli taxonomy and phylogroups. High values of dS, compared to dN, indicate that the E. coli core genome has been subjected to substantial purifying selection over time; significantly more than the non-core part of the genome (pcoli genome size correlated with estimated HGT size (pcoli are largely attained through HGT. No associations were found between selective pressures operating on the E. coli core genome, as estimated using relative entropy, and genome size (p~0.98). On a larger time frame, genome expansion in E. coli, which is significantly associated with the acquisition of virulence factors, appears to be independent of selective forces operating on the core genome.

Measurement of thermal expansion for a Li2TiO3 pebble bed

International Nuclear Information System (INIS)

Hisashi Tanigawa; Mikio Enoeda; Masato Akiba

2006-01-01

In the current design of the blanket with ceramic breeders, pebbles of breeding materials are packed into a container and used as a pebble bed. Thermal and mechanical conditions externally loaded on the bed affect thermal and mechanical properties of the bed. It is necessary to analyze thermo-mechanical properties of the bed under controlled thermal and mechanical conditions. In the present paper, thermal expansion of a Li 2 TiO 3 pebble bed was investigated. Our apparatus consists of a tensile test-apparatus and a measurement chamber. Pebbles of Li 2 TiO 3 with 2 mm diameter were used. They were packed into a container made of alumina. At first, thermal expansion of the apparatus was calibrated because the measured deformation included thermal expansions of the load rods and the container. Instead of the pebble bed, a column made of copper was installed and thermal expansion of the system was measured for the calibration. Taking into account the estimated thermal expansion of the column, thermal expansion of the rods and the container could be analyzed. Based on the correction, thermal expansion of the pebble bed was measured under compression of 0.1 MPa. Temperature of the bed was regulated from room temperature to 973 K. From the measured expansion of the bed, average thermal expansion coefficient was estimated. For the beds with different packing factors ranging from 65.5 to 68.5 %, thermal expansion coefficients were 1.4 ± 0. 10-5 K -1 . In the first measurement of the beds without pre-loading, expansion coefficients were larger for the cooling process than heating. When the beds were successively heated and cooled, the difference decreased. This means that relocation of the pebbles arises in the first heat treatment and progress of compaction is larger in the cooling process than heating. After a few heat treatments, packing states of the beds reach stable and expansion coefficients for both heat and cooling processes are close. In the case of the beds that

Posttraumatic growth in patients who survived cardiac surgery: the predictive and mediating roles of faith-based factors.

Science.gov (United States)

Ai, Amy L; Hall, Daniel; Pargament, Kenneth; Tice, Terrence N

2013-04-01

Despite the growing knowledge of posttraumatic growth, only a few studies have examined personal growth in the context of cardiac health. Similarly, longitudinal research is lacking on the implications of religion/spirituality for patients with advanced cardiac diseases. This paper aims to explore the effect of preoperative religious coping on long-term postoperative personal growth and potential mediation in this effect. Analyses capitalized on a preoperative survey and medical indices from the Society of Thoracic Surgeons' National Database of patients undergoing cardiac surgery. Participants in the current follow-up study completed a mailed survey 30 months after surgery. Hierarchical regression analysis was performed to evaluate the extent to which preoperative use of religious coping predicted growth at follow-up, after controlling for key demographics, medical indices, mental health, and protective factors. Predictors of posttraumatic growth at follow-up were positive religious coping and a living status without a partner. Medical indices, optimistic expectations, social support, and other religious factors were unrelated to posttraumatic growth. Including religious factors diminished effects of gender, age, and race. Including perceived spiritual support completely eliminated the role of positive religious coping, indicating mediation. Preoperative positive religious coping may have a long-term effect on postoperative personal growth, explainable by higher spiritual connections as a part of significance-making. These results suggest that spirituality may play a favorable role in cardiac patients' posttraumatic growth after surviving a life-altering operation. The elimination of demographic effects may help explain previously mixed findings concerning the association between these factors and personal growth.

Local adaptation in migrated interior Douglas-fir seedlings is mediated by ectomycorrhizas and other soil factors.

Science.gov (United States)

Pickles, Brian J; Twieg, Brendan D; O'Neill, Gregory A; Mohn, William W; Simard, Suzanne W

2015-08-01

Separating edaphic impacts on tree distributions from those of climate and geography is notoriously difficult. Aboveground and belowground factors play important roles, and determining their relative contribution to tree success will greatly assist in refining predictive models and forestry strategies in a changing climate. In a common glasshouse, seedlings of interior Douglas-fir (Pseudotsuga menziesii var. glauca) from multiple populations were grown in multiple forest soils. Fungicide was applied to half of the seedlings to separate soil fungal and nonfungal impacts on seedling performance. Soils of varying geographic and climatic distance from seed origin were compared, using a transfer function approach. Seedling height and biomass were optimized following seed transfer into drier soils, whereas survival was optimized when elevation transfer was minimised. Fungicide application reduced ectomycorrhizal root colonization by c. 50%, with treated seedlings exhibiting greater survival but reduced biomass. Local adaptation of Douglas-fir populations to soils was mediated by soil fungi to some extent in 56% of soil origin by response variable combinations. Mediation by edaphic factors in general occurred in 81% of combinations. Soil biota, hitherto unaccounted for in climate models, interacts with biogeography to influence plant ranges in a changing climate. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

On the Equisummability of Hermite and Fourier Expansions

Indian Academy of Sciences (India)

We prove an equisummability result for the Fourier expansions and Hermite expansions as well as special Hermite expansions. We also prove the uniform boundedness of the Bochner-Riesz means associated to the Hermite expansions for polyradial functions.

Non-linear triangle-based polynomial expansion nodal method for hexagonal core analysis

International Nuclear Information System (INIS)

Cho, Jin Young; Cho, Byung Oh; Joo, Han Gyu; Zee, Sung Qunn; Park, Sang Yong

2000-09-01

This report is for the implementation of triangle-based polynomial expansion nodal (TPEN) method to MASTER code in conjunction with the coarse mesh finite difference(CMFD) framework for hexagonal core design and analysis. The TPEN method is a variation of the higher order polynomial expansion nodal (HOPEN) method that solves the multi-group neutron diffusion equation in the hexagonal-z geometry. In contrast with the HOPEN method, only two-dimensional intranodal expansion is considered in the TPEN method for a triangular domain. The axial dependence of the intranodal flux is incorporated separately here and it is determined by the nodal expansion method (NEM) for a hexagonal node. For the consistency of node geometry of the MASTER code which is based on hexagon, TPEN solver is coded to solve one hexagonal node which is composed of 6 triangular nodes directly with Gauss elimination scheme. To solve the CMFD linear system efficiently, stabilized bi-conjugate gradient(BiCG) algorithm and Wielandt eigenvalue shift method are adopted. And for the construction of the efficient preconditioner of BiCG algorithm, the incomplete LU(ILU) factorization scheme which has been widely used in two-dimensional problems is used. To apply the ILU factorization scheme to three-dimensional problem, a symmetric Gauss-Seidel Factorization scheme is used. In order to examine the accuracy of the TPEN solution, several eigenvalue benchmark problems and two transient problems, i.e., a realistic VVER1000 and VVER440 rod ejection benchmark problems, were solved and compared with respective references. The results of eigenvalue benchmark problems indicate that non-linear TPEN method is very accurate showing less than 15 pcm of eigenvalue errors and 1% of maximum power errors, and fast enough to solve the three-dimensional VVER-440 problem within 5 seconds on 733MHz PENTIUM-III. In the case of the transient problems, the non-linear TPEN method also shows good results within a few minute of

On the asymptotic expansions of solutions of an nth order linear differential equation with power coefficients

International Nuclear Information System (INIS)

Paris, R.B.; Wood, A.D.

1984-11-01

The asymptotic expansions of solutions of a class of linear ordinary differential equations of arbitrary order n, containing a factor zsup(m) multiplying the lower order derivatives, are investigated for large values of z in the complex plane. Four classes of solutions are considered which exhibit the following behaviour as /z/ → infinity in certain sectors: (i) solutions whose behaviour is either exponentially large or algebraic (involving p ( < n) algebraic expansions), (ii) solutions which are exponentially small (iii) solutions with a single algebraic expansion and (iv) solutions which are even and odd functions of z whenever n+m is even. The asymptotic expansions of these solutions in a full neigbourhood of the point at infinity are obtained by means of the theory of the solutions in the case m=O developed in a previous paper

Platelet released growth factors boost expansion of bone marrow derived CD34(+) and CD133(+) endothelial progenitor cells for autologous grafting.

Science.gov (United States)

Lippross, Sebastian; Loibl, Markus; Hoppe, Sven; Meury, Thomas; Benneker, Lorin; Alini, Mauro; Verrier, Sophie

2011-01-01

Stem cell based autologous grafting has recently gained mayor interest in various surgical fields for the treatment of extensive tissue defects. CD34(+) and CD133(+) cells that can be isolated from the pool of bone marrow mononuclear cells (BMC) are capable of differentiating into mature endothelial cells in vivo. These endothelial progenitor cells (EPC) are believed to represent a major portion of the angiogenic regenerative cells that are released from bone marrow when tissue injury has occurred. In recent years tissue engineers increasingly looked at the process of vessel neoformation because of its major importance for successful cell grafting to replace damaged tissue. Up to now one of the greatest problems preventing a clinical application is the large scale of expansion that is required for such purpose. We established a method to effectively enhance the expansion of CD34(+) and CD133(+) cells by the use of platelet-released growth factors (PRGF) as a media supplement. PRGF were prepared from thrombocyte concentrates and used as a media supplement to iscove's modified dulbecco's media (IMDM). EPC were immunomagnetically separated from human bone morrow monocyte cells and cultured in IMDM + 10% fetal calf serum (FCS), IMDM + 5%, FCS + 5% PRGF and IMDM + 10% PRGF. We clearly demonstrate a statistically significant higher and faster cell proliferation rate at 7, 14, 21, and 28 days of culture when both PRGF and FCS were added to the medium as opposed to 10% FCS or 10% PRGF alone. The addition of 10% PRGF to IMDM in the absence of FCS leads to a growth arrest from day 14 on. In histochemical, immunocytochemical, and gene-expression analysis we showed that angiogenic and precursor markers of CD34(+) and CD133(+) cells are maintained during long-term culture. In summary, we established a protocol to boost the expansion of CD34(+) and CD133(+) cells. Thereby we provide a technical step towards the clinical application of autologous stem cell

Plasma expansion: fundamentals and applications

International Nuclear Information System (INIS)

Engeln, R; Mazouffre, S; Vankan, P; Bakker, I; Schram, D C

2002-01-01

The study of plasma expansion is interesting from a fundamental point of view as well as from a more applied point of view. We here give a short overview of the way properties like density, velocity and temperature behave in an expanding thermal plasma. Experimental data show that the basic phenomena of plasma expansion are to some extent similar to those of the expansion of a hot neutral gas. From the application point of view, we present first results on the use of an expanding thermal plasma in the plasma-activated catalysis of ammonia, from N 2 -H 2 mixtures

On genus expansion of superpolynomials

Energy Technology Data Exchange (ETDEWEB)

Mironov, Andrei, E-mail: mironov@itep.ru [Lebedev Physics Institute, Moscow 119991 (Russian Federation); ITEP, Moscow 117218 (Russian Federation); National Research Nuclear University MEPhI, Moscow 115409 (Russian Federation); Morozov, Alexei, E-mail: morozov@itep.ru [ITEP, Moscow 117218 (Russian Federation); National Research Nuclear University MEPhI, Moscow 115409 (Russian Federation); Sleptsov, Alexei, E-mail: sleptsov@itep.ru [ITEP, Moscow 117218 (Russian Federation); Laboratory of Quantum Topology, Chelyabinsk State University, Chelyabinsk 454001 (Russian Federation); KdVI, University of Amsterdam (Netherlands); Smirnov, Andrey, E-mail: asmirnov@math.columbia.edu [ITEP, Moscow 117218 (Russian Federation); Columbia University, Department of Mathematics, New York (United States)

2014-12-15

Recently it was shown that the (Ooguri–Vafa) generating function of HOMFLY polynomials is the Hurwitz partition function, i.e. that the dependence of the HOMFLY polynomials on representation R is naturally captured by symmetric group characters (cut-and-join eigenvalues). The genus expansion and expansion through Vassiliev invariants explicitly demonstrate this phenomenon. In the present paper we claim that the superpolynomials are not functions of such a type: symmetric group characters do not provide an adequate linear basis for their expansions. Deformation to superpolynomials is, however, straightforward in the multiplicative basis: the Casimir operators are β-deformed to Hamiltonians of the Calogero–Moser–Sutherland system. Applying this trick to the genus and Vassiliev expansions, we observe that the deformation is fully straightforward only for the thin knots. Beyond the family of thin knots additional algebraically independent terms appear in the Vassiliev and genus expansions. This can suggest that the superpolynomials do in fact contain more information about knots than the colored HOMFLY and Kauffman polynomials. However, even for the thin knots the beta-deformation is non-innocent: already in the simplest examples it seems inconsistent with the positivity of colored superpolynomials in non-(anti)symmetric representations, which also happens in I. Cherednik's (DAHA-based) approach to the torus knots.

HEXIM1 controls satellite cell expansion after injury to regulate skeletal muscle regeneration

Science.gov (United States)

Hong, Peng; Chen, Kang; Huang, Bihui; Liu, Min; Cui, Miao; Rozenberg, Inna; Chaqour, Brahim; Pan, Xiaoyue; Barton, Elisabeth R.; Jiang, Xian-Cheng; Siddiqui, M.A.Q.

2012-01-01

The native capacity of adult skeletal muscles to regenerate is vital to the recovery from physical injuries and dystrophic diseases. Currently, the development of therapeutic interventions has been hindered by the complex regulatory network underlying the process of muscle regeneration. Using a mouse model of skeletal muscle regeneration after injury, we identified hexamethylene bisacetamide inducible 1 (HEXIM1, also referred to as CLP-1), the inhibitory component of the positive transcription elongation factor b (P-TEFb) complex, as a pivotal regulator of skeletal muscle regeneration. Hexim1-haplodeficient muscles exhibited greater mass and preserved function compared with those of WT muscles after injury, as a result of enhanced expansion of satellite cells. Transplanted Hexim1-haplodeficient satellite cells expanded and improved muscle regeneration more effectively than WT satellite cells. Conversely, HEXIM1 overexpression restrained satellite cell proliferation and impeded muscle regeneration. Mechanistically, dissociation of HEXIM1 from P-TEFb and subsequent activation of P-TEFb are required for satellite cell proliferation and the prevention of early myogenic differentiation. These findings suggest a crucial role for the HEXIM1/P-TEFb pathway in the regulation of satellite cell–mediated muscle regeneration and identify HEXIM1 as a potential therapeutic target for degenerative muscular diseases. PMID:23023707

Egr-1 and serum response factor are involved in growth factors- and serum-mediated induction of E2-EPF UCP expression that regulates the VHL-HIF pathway.

Science.gov (United States)

Lim, Jung Hwa; Jung, Cho-Rok; Lee, Chan-Hee; Im, Dong-Soo

2008-11-01

E2-EPF ubiquitin carrier protein (UCP) has been shown to be highly expressed in common human cancers and target von Hippel-Lindau (VHL) for proteosomal degradation in cells, thereby stabilizing hypoxia-inducible factor (HIF)-1alpha. Here, we investigated cellular factors that regulate the expression of UCP gene. Promoter deletion assay identified binding sites for early growth response-1 (Egr-1) and serum response factor (SRF) in the UCP promoter. Hepatocyte or epidermal growth factor (EGF), or phorbol 12-myristate 13-acetate induced UCP expression following early induction of Egr-1 expression in HeLa cells. Serum increased mRNA and protein levels of SRF and UCP in the cell. By electrophoretic mobility shift and chromatin immunoprecipitation assays, sequence-specific DNA-binding of Egr-1 and SRF to the UCP promoter was detected in nuclear extracts from HeLa cells treated with EGF and serum, respectively. Overexpression of Egr-1 or SRF increased UCP expression. RNA interference-mediated depletion of endogenous Egr-1 or SRF impaired EGF- or serum-mediated induction of UCP expression, which was required for cancer cell proliferation. Systemic delivery of EGF into mice also increased UCP expression following early induction of Egr-1 expression in mouse liver. The induced UCP expression by the growth factors or serum increased HIF-1alpha protein level under non-hypoxic conditions, suggesting that the Egr-1/SRF-UCP-VHL pathway is in part responsible for the increased HIF-1alpha protein level in vitro and in vivo. Thus, growth factors and serum induce expression of Egr-1 and SRF, respectively, which in turn induces UCP expression that positively regulates cancer cell growth.

Inhibition of CRM1-mediated nuclear export of transcription factors by leukemogenic NUP98 fusion proteins.

Science.gov (United States)

Takeda, Akiko; Sarma, Nayan J; Abdul-Nabi, Anmaar M; Yaseen, Nabeel R

2010-05-21

NUP98 is a nucleoporin that plays complex roles in the nucleocytoplasmic trafficking of macromolecules. Rearrangements of the NUP98 gene in human leukemia result in the expression of numerous fusion oncoproteins whose effect on nucleocytoplasmic trafficking is poorly understood. The present study was undertaken to determine the effects of leukemogenic NUP98 fusion proteins on CRM1-mediated nuclear export. NUP98-HOXA9, a prototypic NUP98 fusion, inhibited the nuclear export of two known CRM1 substrates: mutated cytoplasmic nucleophosmin and HIV-1 Rev. In vitro binding assays revealed that NUP98-HOXA9 binds CRM1 through the FG repeat motif in a Ran-GTP-dependent manner similar to but stronger than the interaction between CRM1 and its export substrates. Two NUP98 fusions, NUP98-HOXA9 and NUP98-DDX10, whose fusion partners are structurally and functionally unrelated, interacted with endogenous CRM1 in myeloid cells as shown by co-immunoprecipitation. These leukemogenic NUP98 fusion proteins interacted with CRM1, Ran, and the nucleoporin NUP214 in a manner fundamentally different from that of wild-type NUP98. NUP98-HOXA9 and NUP98-DDX10 formed characteristic aggregates within the nuclei of a myeloid cell line and primary human CD34+ cells and caused aberrant localization of CRM1 to these aggregates. These NUP98 fusions caused nuclear accumulation of two transcription factors, NFAT and NFkappaB, that are regulated by CRM1-mediated export. The nuclear entrapment of NFAT and NFkappaB correlated with enhanced transcription from promoters responsive to these transcription factors. Taken together, the results suggest a new mechanism by which NUP98 fusions dysregulate transcription and cause leukemia, namely, inhibition of CRM1-mediated nuclear export with aberrant nuclear retention of transcriptional regulators.

Improved streaming analysis technique: spherical harmonics expansion of albedo data

International Nuclear Information System (INIS)

Albert, T.E.; Simmons, G.L.

1979-01-01

An improved albedo scattering technique was implemented with a three-dimensional Monte Carlo transport code for use in analyzing radiation streaming problems. The improvement was based on a shifted spherical Harmonics expansion of the doubly differential albedo data base. The result of the improvement was a factor of 3 to 10 reduction in data storage requirements and approximately a factor of 3 to 6 increase in computational speed. Comparisons of results obtained using the technique with measurements are shown for neutron streaming in one- and two-legged square concrete ducts

Auxin-dependent compositional change in Mediator in ARF7- and ARF19-mediated transcription.

Science.gov (United States)

Ito, Jun; Fukaki, Hidehiro; Onoda, Makoto; Li, Lin; Li, Chuanyou; Tasaka, Masao; Furutani, Masahiko

2016-06-07

Mediator is a multiprotein complex that integrates the signals from transcription factors binding to the promoter and transmits them to achieve gene transcription. The subunits of Mediator complex reside in four modules: the head, middle, tail, and dissociable CDK8 kinase module (CKM). The head, middle, and tail modules form the core Mediator complex, and the association of CKM can modify the function of Mediator in transcription. Here, we show genetic and biochemical evidence that CKM-associated Mediator transmits auxin-dependent transcriptional repression in lateral root (LR) formation. The AUXIN/INDOLE 3-ACETIC ACID 14 (Aux/IAA14) transcriptional repressor inhibits the transcriptional activity of its binding partners AUXIN RESPONSE FACTOR 7 (ARF7) and ARF19 by making a complex with the CKM-associated Mediator. In addition, TOPLESS (TPL), a transcriptional corepressor, forms a bridge between IAA14 and the CKM component MED13 through the physical interaction. ChIP assays show that auxin induces the dissociation of MED13 but not the tail module component MED25 from the ARF7 binding region upstream of its target gene. These findings indicate that auxin-induced degradation of IAA14 changes the module composition of Mediator interacting with ARF7 and ARF19 in the upstream region of their target genes involved in LR formation. We suggest that this regulation leads to a quick switch of signal transmission from ARFs to target gene expression in response to auxin.

The status of intercultural mediation in translation: Is it an absolute licence?

Directory of Open Access Journals (Sweden)

Akbari Alireza

2017-06-01

Full Text Available The role of translator as Sprachmittler or intercultural mediator has welcomed much attention since the advent of the “cultural turn” paradigm. The present research paper seeks to figure out how the manifestations of intercultural mediation are achieved via translation in terms of two mediation facets, viz, personal and communicated interpretations. Whereas the former deals with the presence of the translator between the source and target cultures, the latter concerns the role of the reader of the translated text in the target language through several mediational strategies including: expansion, reframing, replacement, eschewing of dispreferred structure, and dispensation to capture the message of the source text. The rationale for focusing on these strategies lies in the fact that translators often utilize transliteration and literal translation strategies when it comes to cultural items and concepts. As far as review of the literature indicates, mediational translation has not received due attention in the Persian language since it differs in comparison with other languages such as English, French etc. In the case of language patterning, such study reveals some novel but applicable cultural translation strategies that highlight the nature of mediation in cultural translation.

On summation of perturbation expansions

International Nuclear Information System (INIS)

Horzela, A.

1985-04-01

The problem of the restoration of physical quantities defined by divergent perturbation expansions is analysed. The Pad'e and Borel summability is proved for alternating perturbation expansions with factorially growing coefficients. The proof is based on the methods of the classical moments theory. 17 refs. (author)

OPEC future capacity expansions

International Nuclear Information System (INIS)

Sandrea, I.

2005-01-01

This conference presentation examined OPEC future capacity expansions including highlights from 2000-2004 from the supply perspective and actions by OPEC; OPEC spare capacity in 2005/2006; medium-term capacity expansion and investments; long-term scenarios, challenges and opportunities; and upstream policies in member countries. Highlights from the supply perspective included worst than expected non-OPEC supply response; non-OPEC supply affected by a number of accidents and strikes; geopolitical tensions; and higher than expected demand for OPEC crude. OPEC's actions included closer relationship with other producers and consumers; capacity expansions in 2004 and 2005/2006; and OPEC kept the market well supplied with crude in 2004. The presentation also provided data using graphical charts on OPEC net capacity additions until 2005/2006; OPEC production versus spare capacity from 2003 to 2005; OPEC production and capacity to 2010; and change in required OPEC production from 2005-2020. Medium term expansion to 2010 includes over 60 projects. Medium-term risks such as project execution, financing, costs, demand, reserves, depletion, integration of Iraq, and geopolitical tensions were also discussed. The presentation concluded that in the long term, large uncertainties remain; the peak of world supply is not imminent; and continued and enhanced cooperation is essential to market stability. tabs., figs

On Learning Ring-Sum-Expansions

DEFF Research Database (Denmark)

Fischer, Paul; Simon, H. -U.

1992-01-01

The problem of learning ring-sum-expansions from examples is studied. Ring-sum-expansions (RSE) are representations of Boolean functions over the base {#123;small infinum, (+), 1}#125;, which reflect arithmetic operations in GF(2). k-RSE is the class of ring-sum-expansions containing only monomials...... of length at most k:. term-RSE is the class of ring-sum-expansions having at most I: monomials. It is shown that k-RSE, k>or=1, is learnable while k-term-RSE, k>2, is not learnable if RPnot=NP. Without using a complexity-theoretical hypothesis, it is proven that k-RSE, k>or=1, and k-term-RSE, k>or=2 cannot...... be learned from positive (negative) examples alone. However, if the restriction that the hypothesis which is output by the learning algorithm is also a k-RSE is suspended, then k-RSE is learnable from positive (negative) examples only. Moreover, it is proved that 2-term-RSE is learnable by a conjunction...

The bootstrap and edgeworth expansion

CERN Document Server

Hall, Peter

1992-01-01

This monograph addresses two quite different topics, in the belief that each can shed light on the other. Firstly, it lays the foundation for a particular view of the bootstrap. Secondly, it gives an account of Edgeworth expansion. Chapter 1 is about the bootstrap, witih almost no mention of Edgeworth expansion; Chapter 2 is about Edgeworth expansion, with scarcely a word about the bootstrap; and Chapters 3 and 4 bring these two themes together, using Edgeworth expansion to explore and develop the properites of the bootstrap. The book is aimed a a graduate level audience who has some exposure to the methods of theoretical statistics. However, technical details are delayed until the last chapter (entitled "Details of Mathematical Rogour"), and so a mathematically able reader without knowledge of the rigorous theory of probability will have no trouble understanding the first four-fifths of the book. The book simultaneously fills two gaps in the literature; it provides a very readable graduate level account of t...

Therapeutic potential of Mediator complex subunits in metabolic diseases.

Science.gov (United States)

Ranjan, Amol; Ansari, Suraiya A

2018-01-01

The multisubunit Mediator is an evolutionary conserved transcriptional coregulatory complex in eukaryotes. It is needed for the transcriptional regulation of gene expression in general as well as in a gene specific manner. Mediator complex subunits interact with different transcription factors as well as components of RNA Pol II transcription initiation complex and in doing so act as a bridge between gene specific transcription factors and general Pol II transcription machinery. Specific interaction of various Mediator subunits with nuclear receptors (NRs) and other transcription factors involved in metabolism has been reported in different studies. Evidences indicate that ligand-activated NRs recruit Mediator complex for RNA Pol II-dependent gene transcription. These NRs have been explored as therapeutic targets in different metabolic diseases; however, they show side-effects as targets due to their overlapping involvement in different signaling pathways. Here we discuss the interaction of various Mediator subunits with transcription factors involved in metabolism and whether specific interaction of these transcription factors with Mediator subunits could be potentially utilized as therapeutic strategy in a variety of metabolic diseases. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

A fully defined and scalable 3D culture system for human pluripotent stem cell expansion and differentiation

Science.gov (United States)

Lei, Yuguo; Schaffer, David V.

2013-12-01

Human pluripotent stem cells (hPSCs), including human embryonic stem cells and induced pluripotent stem cells, are promising for numerous biomedical applications, such as cell replacement therapies, tissue and whole-organ engineering, and high-throughput pharmacology and toxicology screening. Each of these applications requires large numbers of cells of high quality; however, the scalable expansion and differentiation of hPSCs, especially for clinical utilization, remains a challenge. We report a simple, defined, efficient, scalable, and good manufacturing practice-compatible 3D culture system for hPSC expansion and differentiation. It employs a thermoresponsive hydrogel that combines easy manipulation and completely defined conditions, free of any human- or animal-derived factors, and entailing only recombinant protein factors. Under an optimized protocol, the 3D system enables long-term, serial expansion of multiple hPSCs lines with a high expansion rate (∼20-fold per 5-d passage, for a 1072-fold expansion over 280 d), yield (∼2.0 × 107 cells per mL of hydrogel), and purity (∼95% Oct4+), even with single-cell inoculation, all of which offer considerable advantages relative to current approaches. Moreover, the system enabled 3D directed differentiation of hPSCs into multiple lineages, including dopaminergic neuron progenitors with a yield of ∼8 × 107 dopaminergic progenitors per mL of hydrogel and ∼80-fold expansion by the end of a 15-d derivation. This versatile system may be useful at numerous scales, from basic biological investigation to clinical development.

Syndemic Factors Mediate the Relationship between Sexual Stigma and Depression among Sexual Minority Women and Gender Minorities.

Science.gov (United States)

Logie, Carmen H; Lacombe-Duncan, Ashley; Poteat, Tonia; Wagner, Anne C

Stigma and discrimination contribute to elevated depression risks among sexual minority women (SMW) and gender minority (GM) people who identify as lesbian, bisexual, or queer. Syndemics theory posits that adverse psychosocial outcomes cluster to negatively impact health and mental health outcomes among sexual minorities. We tested whether a syndemic condition composed of low social support, low self-rated health, low self-esteem, and economic insecurity mediated the relationship between sexual stigma and depressive symptoms among SMW/GM. We implemented a cross-sectional, Internet-based survey with SMW and GM in Toronto, Canada. We conducted structural equation modeling using maximum likelihood estimation to test a conceptual model of pathways between sexual stigma, syndemic factors, and depressive symptoms. A total of 391 SMW/GM with a mean age of 30.9 (SD = 7.62) were included in the analysis. The model fit for a latent syndemics construct consisting of psychosocial variables (low social support, low self-rated health, low self-esteem, economic insecurity) was very good (χ 2  = 6.022, df = 2, p = .049; comparative fit index = 0.973, Tucker-Lewis index = 0.918, root-mean square error of approximation = 0.072). In the simultaneous model, sexual stigma had a significant direct effect on depression. When the syndemic variable was added as a mediator, the direct path from sexual stigma to depression was no longer significant, suggesting mediation. The model fit the data well: χ2 = 33.50, df = 12, p = .001; comparative fit index = 0.951, Tucker-Lewis index = 0.915, root-mean square error of approximation = 0.068. Our results highlight the salience of considering both sexual stigma and syndemic factors to explain mental health disparities experienced by SMW and GM. Addressing sexual stigma in the context of co-occurring psychosocial factors and economic insecurity will be key to achieving optimal health for SMW and GM. Copyright © 2017 Jacobs

Fuel Thermal Expansion (FTHEXP)

International Nuclear Information System (INIS)

Reymann, G.A.

1978-07-01

A model is presented which deals with dimensional changes in LWR fuel pellets caused by changes in temperature. It is capable of dealing with any combination of UO 2 and PuO 2 in solid, liquid or mixed phase states, and includes expansion due to the solid-liquid phase change. The function FTHEXP models fuel thermal expansion as a function of temperature, fraction of PuO 2 , and the fraction of fuel which is molten

Node-Expansion Operators for the UCT Algorithm

Science.gov (United States)

Yajima, Takayuki; Hashimoto, Tsuyoshi; Matsui, Toshiki; Hashimoto, Junichi; Spoerer, Kristian

Recent works on the MCTS and UCT framework in the domain of Go focused on introducing knowledge to the playout and on pruning variations from the tree, but so far node expansion has not been investigated. In this paper we show that delaying expansion according to the number of the siblings delivers a gain of more than 92% when compared to normal expansion. We propose three improvements; one that uses domain knowledge and two that are domain-independent methods. Experimental results show that all advanced operators significantly improve the UCT performance when compared to the basic delaying expansion. From the results we may conclude that the new expansion operators are an appropriate means to improve the UCT algorithm.

Reevaluating Suitability Estimates Based on Dynamics of Cropland Expansion in the Brazilian Amazon

Science.gov (United States)

Morton, Douglas C.; Noojipady, Praveen; Macedo, Marcia M.; Victoria, Daniel C.; Bolfe, Edson L.

2016-01-01

Agricultural suitability maps are a key input for land use zoning and projections of cropland expansion. Suitability assessments typically consider edaphic conditions, climate, crop characteristics, and sometimes incorporate accessibility to transportation and market infrastructure. However, correct weighting among these disparate factors is challenging, given rapid development of new crop varieties, irrigation, and road networks, as well as changing global demand for agricultural commodities. Here, we compared three independent assessments of cropland suitability to spatial and temporal dynamics of agricultural expansion in the Brazilian state of Mato Grosso during 2001 2012. We found that areas of recent cropland expansion identified using satellite data were generally designated as low to moderate suitability for rainfed crop production. Our analysis highlighted the abrupt nature of suitability boundaries, rather than smooth gradients of agricultural potential, with little additional cropland expansion beyond the extent of the flattest areas (0-2% slope). Satellite-based estimates of the interannual variability in the use of existing crop areas also provided an alternate means to assess suitability. On average, cropland areas in the Cerrado biome had higher utilization (84%) than croplands in the Amazon region of northern Mato Grosso (74%). Areas of more recent expansion had lower utilization than croplands established before 2002, providing empirical evidence for lower suitability or alternative management strategies (e.g., pasture soya rotations) for lands undergoing more recent land use transitions. This unplanted reserve constitutes a large area of potentially available cropland (PAC)without further expansion, within the management limits imposed for pest management and fallow cycles. Using two key constraints on future cropland expansion, slope and restrictions on further deforestation of Amazon or Cerrado vegetation, we found little available flat land for

Plant Mediator complex and its critical functions in transcription regulation.

Science.gov (United States)

Yang, Yan; Li, Ling; Qu, Li-Jia

2016-02-01

The Mediator complex is an important component of the eukaryotic transcriptional machinery. As an essential link between transcription factors and RNA polymerase II, the Mediator complex transduces diverse signals to genes involved in different pathways. The plant Mediator complex was recently purified and comprises conserved and specific subunits. It functions in concert with transcription factors to modulate various responses. In this review, we summarize the recent advances in understanding the plant Mediator complex and its diverse roles in plant growth, development, defense, non-coding RNA production, response to abiotic stresses, flowering, genomic stability and metabolic homeostasis. In addition, the transcription factors interacting with the Mediator complex are also highlighted. © 2015 Institute of Botany, Chinese Academy of Sciences.

Hadronic wave functions at short distances and the operator product expansion

International Nuclear Information System (INIS)

Brodsky, S.J.; Lepage, G.P.

1980-01-01

The operator product expansion, of appropriate products of quark fields, is used to find the anamalous dimensions which control the short distance behavior of hadronic wave functions. This vehavior in turn controls the high-Q 2 limit of hadronic form factors. In particular, we relate each anamalous dimension of the nonsinglet structure functions to a corresponding logarithmic correction factor to the nominal αsub(s)(Q 2 )/Q 2 fall off of meson form factors. Unlike the case of deep inelastic lepton-hadron scattering, the operator product necessary here involves extra terms which do not contribute to forward matrix elements. (orig.)

Message encipherment with minimal expansion and redundancy : doing better than ISO-19126

NARCIS (Netherlands)

Jansen, C.J.A.; Vlist, van der P.

1996-01-01

In this paper we consider the problem of encrypting messages containing characters from small, usually non-binary alphabets by means of binary encryption algorithms. It is shown that the solutions as proposed by ISO-10126 can be improved with respect to the expansion factor and, more importantly,

Regulation of tissue factor and inflammatory mediators by Egr-1 in a mouse endotoxemia model.

Science.gov (United States)

Pawlinski, Rafal; Pedersen, Brian; Kehrle, Bettina; Aird, William C; Frank, Rolf D; Guha, Mausumee; Mackman, Nigel

2003-05-15

In septic shock, tissue factor (TF) activates blood coagulation, and cytokines and chemokines orchestrate an inflammatory response. In this study, the role of Egr-1 in lipopolysaccharide (LPS) induction of TF and inflammatory mediators in vivo was evaluated using Egr-1(+/+) and Egr-1(-/-) mice. Administration of LPS transiently increased the steady-state levels of Egr-1 mRNA in the kidneys and lungs of Egr-1(+/+) mice with maximal induction at one hour. Egr-1 was expressed in epithelial cells in the kidneys and lungs in untreated and LPS-treated mice. LPS induction of monocyte chemoattractant protein mRNA in the kidneys and lungs of Egr-1(-/-) mice was not affected at 3 hours, but its expression was significantly reduced at 8 hours compared with the expression observed in Egr-1(+/+) mice. Similarly, LPS induction of TF mRNA expression in the kidneys and lungs at 8 hours was reduced in Egr-1(-/-) mice. However, Egr-1 deficiency did not affect plasma levels of tumor necrosis factor alpha in endotoxemic mice. Moreover, Egr-1(+/+) and Egr-1(-/-) mice exhibited similar survival times in a model of acute endotoxemia. These data indicate that Egr-1 does not contribute to the early inflammatory response in the kidneys and lungs or the early systemic inflammatory response in endotoxemic mice. However, Egr-1 does contribute to the sustained expression of inflammatory mediators and to the maximal expression of TF at 8 hours in the kidneys and lungs.

Thermal expansion in small metallic particles

International Nuclear Information System (INIS)

Ivanov, A.S.

1985-01-01

An anomalously low thermal expansion observable in small particles is attributed to extending effect of the shell. It is shown that the coefficient of thermal expansion of the oxide-film-coated aluminium particles calculated using elastic constants and coefficients of thermal expansion of massive materials agres well with those measured experimentally. The linear dilatation of the shell, its stress to rupture and the values of the structural tension are estimated vs the temperature

Wnt3a nanodisks promote ex vivo expansion of hematopoietic stem and progenitor cells

DEFF Research Database (Denmark)

Lalefar, Nahal R.; Witkowski, Andrzej; Simonsen, Jens Bæk

2016-01-01

Background : Wnt proteins modulate development, stem cell fate and cancer through interactions with cell surface receptors. Wnts are cysteine-rich, glycosylated, lipid modified, two domain proteins that are prone to aggregation. The culprit responsible for this behavior is a covalently bound palm...... to Lin- Sca-1+ c-Kit+ cell expansion, an effect that was not mediated through β-catenin. Conclusions : The data indicate Wnt3a ND constitute a water-soluble transport vehicle capable of promoting ex vivo expansion of HSPC.......Background : Wnt proteins modulate development, stem cell fate and cancer through interactions with cell surface receptors. Wnts are cysteine-rich, glycosylated, lipid modified, two domain proteins that are prone to aggregation. The culprit responsible for this behavior is a covalently bound...... palmitoleoyl moiety in the N-terminal domain. Results : By combining murine Wnt3a with phospholipid and apolipoprotein A-I, ternary complexes termed nanodisks (ND) were generated. ND-associated Wnt3a is soluble in the absence of detergent micelles and gel filtration chromatography revealed that Wnt3a co...

Histone modifications influence mediator interactions with chromatin

Science.gov (United States)

Zhu, Xuefeng; Zhang, Yongqiang; Bjornsdottir, Gudrun; Liu, Zhongle; Quan, Amy; Costanzo, Michael; Dávila López, Marcela; Westholm, Jakub Orzechowski; Ronne, Hans; Boone, Charles; Gustafsson, Claes M.; Myers, Lawrence C.

2011-01-01

The Mediator complex transmits activation signals from DNA bound transcription factors to the core transcription machinery. Genome wide localization studies have demonstrated that Mediator occupancy not only correlates with high levels of transcription, but that the complex also is present at transcriptionally silenced locations. We provide evidence that Mediator localization is guided by an interaction with histone tails, and that this interaction is regulated by their post-translational modifications. A quantitative, high-density genetic interaction map revealed links between Mediator components and factors affecting chromatin structure, especially histone deacetylases. Peptide binding assays demonstrated that pure wild-type Mediator forms stable complexes with the tails of Histone H3 and H4. These binding assays also showed Mediator—histone H4 peptide interactions are specifically inhibited by acetylation of the histone H4 lysine 16, a residue critical in transcriptional silencing. Finally, these findings were validated by tiling array analysis that revealed a broad correlation between Mediator and nucleosome occupancy in vivo, but a negative correlation between Mediator and nucleosomes acetylated at histone H4 lysine 16. Our studies show that chromatin structure and the acetylation state of histones are intimately connected to Mediator localization. PMID:21742760

[Tissular expansion in giant congenital nevi treatment].

Science.gov (United States)

Nguyen Van Nuoi, V; Francois-Fiquet, C; Diner, P; Sergent, B; Zazurca, F; Franchi, G; Buis, J; Vazquez, M-P; Picard, A; Kadlub, N

2014-08-01

Surgical management of giant melanotic naevi remains a surgical challenge. Tissue expansion provides tissue of the same quality for the repair of defects. The aim of this study is to review tissular expansion for giant melanotic naevi. We conducted a retrospective study from 2000 to 2012. All children patients who underwent a tissular expansion for giant congenital naevi had been included. Epidemiological data, surgical procedure, complication rate and results had been analysed. Thirty-tree patients had been included; they underwent 61 procedures with 79 tissular-expansion prosthesis. Previous surgery, mostly simple excision had been performed before tissular expansion. Complete naevus excision had been performed in 63.3% of the cases. Complications occurred in 45% of the cases, however in 50% of them were minor. Iterative surgery increased the complication rate. Tissular expansion is a valuable option for giant congenital naevus. However, complication rate remained high, especially when iterative surgery is needed. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Advanced model for expansion of natural gas distribution networks based on geographic information systems

Energy Technology Data Exchange (ETDEWEB)

Ramirez-Rosado, I.J.; Fernandez-Jimenez, L.A.; Garcia-Garrido, E.; Zorzano-Santamaria, P.; Zorzano-Alba, E. [La Rioja Univ., La Rioja (Spain). Dept. of Electrical Engineering; Miranda, V.; Montneiro, C. [Porto Univ., Porto (Portugal). Faculty of Engineering]|[Inst. de Engenharia de Sistemas e Computadores do Porto, Porto (Portugal)

2005-07-01

An advanced geographic information system (GIS) model of natural gas distribution networks was presented. The raster-based model was developed to evaluate costs associated with the expansion of electrical networks due to increased demand in the La Rioja region of Spain. The model was also used to evaluate costs associated with maintenance and amortization of the already existing distribution network. Expansion costs of the distribution network were modelled in various demand scenarios. The model also considered a variety of technical factors associated with pipeline length and topography. Soil and slope data from previous pipeline projects were used to estimate real costs per unit length of pipeline. It was concluded that results obtained by the model will be used by planners to select zones where expansion is economically feasible. 4 refs., 5 figs.

Development of maternal seed tissue in barley is mediated by regulated cell expansion and cell disintegration and coordinated with endosperm growth.

Science.gov (United States)

Radchuk, Volodymyr; Weier, Diana; Radchuk, Ruslana; Weschke, Winfriede; Weber, Hans

2011-01-01

After fertilization, filial grain organs are surrounded by the maternal nucellus embedded within the integuments and pericarp. Rapid early endosperm growth must be coordinated with maternal tissue development. Parameters of maternal tissue growth and development were analysed during early endosperm formation. In the pericarp, cell proliferation is accomplished around the time of fertilization, followed by cell elongation predominantly in longitudinal directions. The rapid cell expansion coincides with endosperm cellularization. Distribution of TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling)-positive nuclei reveals distinct patterns starting in the nucellus at anthesis and followed later by the inner cell rows of the pericarp, then spreading to the whole pericarp. The pattern suggests timely and spatially regulated programmed cell death (PCD) processes in maternal seed tissues. When the endosperm is coenocytic, PCD events are only observed within the nucellus. Thereby, remobilization of nucellar storage compounds by PCD could nourish the early developing endosperm when functional interconnections are absent between maternal and filial seed organs. Specific proteases promote PCD events. Characterization of the barley vacuolar processing enzyme (VPE) gene family identified seven gene members specifically expressed in the developing grain. HvVPE2a (known as nucellain) together with closely similar HvVPE2b and HvVPE2d might be involved in nucellar PCD. HvVPE4 is strongly cell specific for pericarp parenchyma. Correlative evidence suggests that HvVPE4 plays a role in PCD events in the pericarp. Possible functions of PCD in the maternal tissues imply a potential nutritive role or the relief of a physical restraint for endosperm growth. PCD could also activate post-phloem transport functions.

Negative thermal expansion in functional materials: controllable thermal expansion by chemical modifications.

Science.gov (United States)

Chen, Jun; Hu, Lei; Deng, Jinxia; Xing, Xianran

2015-06-07

Negative thermal expansion (NTE) is an intriguing physical property of solids, which is a consequence of a complex interplay among the lattice, phonons, and electrons. Interestingly, a large number of NTE materials have been found in various types of functional materials. In the last two decades good progress has been achieved to discover new phenomena and mechanisms of NTE. In the present review article, NTE is reviewed in functional materials of ferroelectrics, magnetics, multiferroics, superconductors, temperature-induced electron configuration change and so on. Zero thermal expansion (ZTE) of functional materials is emphasized due to the importance for practical applications. The NTE functional materials present a general physical picture to reveal a strong coupling role between physical properties and NTE. There is a general nature of NTE for both ferroelectrics and magnetics, in which NTE is determined by either ferroelectric order or magnetic one. In NTE functional materials, a multi-way to control thermal expansion can be established through the coupling roles of ferroelectricity-NTE, magnetism-NTE, change of electron configuration-NTE, open-framework-NTE, and so on. Chemical modification has been proved to be an effective method to control thermal expansion. Finally, challenges and questions are discussed for the development of NTE materials. There remains a challenge to discover a "perfect" NTE material for each specific application for chemists. The future studies on NTE functional materials will definitely promote the development of NTE materials.

Applications of the large mass expansion

International Nuclear Information System (INIS)

Fleischer, J.; Kotikov, A.V.; ); Veretin, O.L.

1998-01-01

The method of the large mass expansion (LME) is investigated for selfenergy and vertex functions in two-loop order. It has the technical advantage that in many cases the expansion coefficients can be expressed analytically. As long as only one non-zero external momentum squared, q 2 , is involved also the Taylor expansion (TE) w.r.t. small q 2 yields high precision results in a domain sufficient for most applications. In the case of only one non-zero mass M and only one external momentum squared, the expansion w.r.t. q 2 /M 2 is identical for the TE and the LME. In this case the combined techniques yield analytic expressions for many diagrams, which are quite easy to handle numerically. (author)

Association between the Five Factor personality traits and perceived stress: is the effect mediated by general self-efficacy?

DEFF Research Database (Denmark)

Ebstrup, Jeanette Frost; Eplov, Lene Falgaard; Pisinger, Charlotta

2011-01-01

Ill-health resulting from chronic stress is influenced by personality traits leading to different ways of appraising and coping with life's daily hassles. Using a large population sample the study aimed to investigate possible associations between perceived stress and the personality dimensions......-significant - whilst neuroticism had a positive association. The associations with agreeableness and openness became positive and significant, respectively, when GSE was included. All five personality-stress models were mediated by GSE, with extroversion and conscientiousness having the strongest mediating effect....... The strongest stress-association was found for neuroticism. GSE was shown to change the impact and interpretation of the personality dimensions on perceived stress. These results indicate that GSE is an important factor to consider in the link between personality and perceived stress....

The mediating role of dietary factors and leisure time physical activity on socioeconomic inequalities in body mass index among Australian adults.

Science.gov (United States)

Gearon, Emma; Backholer, Kathryn; Hodge, Allison; Peeters, Anna

2013-12-21

The relationship between socioeconomic position and obesity has been clearly established, however, the extent to which specific behavioural factors mediate this relationship is less clear. This study aimed to ascertain the contribution of specific dietary elements and leisure-time physical activity (LTPA) to variations in obesity with education in the baseline (1990-1994) Melbourne Collaborative Cohort Study (MCCS). 18, 489 women and 12, 141 men were included in this cross-sectional analysis. A series of linear regression models were used in accordance with the products of coefficients method to examine the mediating role of alcohol, soft drink (regular and diet), snacks (healthy and sweet), savoury items (healthy and unhealthy), meeting fruit and vegetable guidelines and LTPA on the relationship between education and body mass index (BMI). Compared to those with lowest educational attainment, those with the highest educational attainment had a 1 kg/m2 lower BMI. Among men and women, 27% and 48%, respectively, of this disparity was attributable to differences in LTPA and diet. Unhealthy savoury item consumption and LTPA contributed most to the mediated effects for men and women. Alcohol and diet soft drink were additionally important mediators for women. Diet and LTPA are potentially modifiable behavioural risk factors for the development of obesity that contribute substantially to inequalities in BMI. Our findings highlight the importance of specific behaviours which may be useful to the implementation of effective, targeted public policy to reduce socioeconomic inequalities in obesity.

Research of the influencing factors of the immobilized redox mediators accelerating Cr(Ⅵ reduction by Escherichia coli BL21

Directory of Open Access Journals (Sweden)

Jiapeng PING

2017-10-01

Full Text Available In order to study the influencing factors of non-dissolved redox mediators on Cr (Ⅵ bioreduction, the accelerating effect of non-dissolved redox mediators immobilized by cellulose acetate (CA on the reduction of Cr(Ⅵ by Escherichia coli BL21 is investigated. The results show that the accelerating order is 1-chloroanthraquinone>1,5-dichloroanthraquinone>2-chloroanthraquinone>1,8-dichloroanthraquinone>anthraquinone>1,4,5,8-tetrachloroanthtaquinone; the optimal concentration of 1-chloroanthraquinone pH and initial Cr(Ⅵ concentration are 0.048 mol/L, 7.00 and 30 mg/L, respectively; the removal rate increases with the increasing temperature when it is in the range of 20~60 ℃; after 6 times of recycling experiments, and the Cr(Ⅵ bioreduction rate with the immobilized 1-chloroanthraquinone maintains above 5 times of margin bacterium's. It indicates that non-dissolved redox mediators immobilized by CA can effectively accelerate the reduction rate of Cr(Ⅵ by Escherichia coli BL21, which has favourable application value.

Public acceptance and preferences related to renewable energy and grid expansion policy: Empirical insights for Germany

International Nuclear Information System (INIS)

Bertsch, Valentin; Hall, Margeret; Weinhardt, Christof; Fichtner, Wolf

2016-01-01

The rapid expansion of renewable energy sources (RES) in many European countries brings about transmission grid expansion requirements. While the transition towards RES-based energy systems is largely perceived positively in general, locally both RES and grid expansion are often confronted with a lack of public acceptance. Using Germany as a case study, we analyse public acceptance of energy infrastructure and its main drivers on local vs. national levels. For this purpose, we conducted a nationally representative survey. Our results show that, on a national level, the acceptance of RES is very high and there is also a high acceptance of grid expansion if it helps to increase the share of RES in the system. In terms of local acceptance problems that may arise for most considered technologies, concerns about landscape modification turn out to be the main driving factor. Moreover, the distance between places of residence and places of energy infrastructure construction is crucial. While acceptance or rejection of technologies will never be entirely tangible or explicable, we find the explicability of rejections to be lowest for new technologies. Finally, age and education turn out to be the most relevant socio-demographic variables determining the participants' acceptance. - Highlights: • A survey to understand drivers of energy technology acceptance was conducted. • Participants were asked to rank energy policy objectives. • Strong differences between acceptance on a national vs. a local level were found. • Landscape modification is the most important factor driving the local acceptance. • Age and education turned out to be the most relevant socio-demographic factors.

The role of burnout syndrome as a mediator for the effect of psychosocial risk factors on the intensity of musculoskeletal disorders: a structural equation modeling approach.

Science.gov (United States)

Gholami, Tahereh; Pahlavian, Ahmad Heidari; Akbarzadeh, Mahdi; Motamedzade, Majid; Moghaddam, Rashid Heidari

2016-01-01

This study examined the hypothesis that burnout syndrome mediates effects of psychosocial risk factors and intensity of musculoskeletal disorders (MSDs) among hospital nurses. The sample was composed of 415 nurses from various wards across five hospitals of Iran's Hamedan University of Medical Sciences. Data were collected through three questionnaires: job content questionnaire, Maslach burnout inventory and visual analogue scale. Results of structural equation modeling with a mediating effect showed that psychosocial risk factors were significantly related to changes in burnout, which in turn affects intensity of MSDs.

Leiomyoma-derived transforming growth factor-β impairs bone morphogenetic protein-2-mediated endometrial receptivity.

Science.gov (United States)

Doherty, Leo F; Taylor, Hugh S

2015-03-01

To determine whether transforming growth factor (TGF)-β3 is a paracrine signal secreted by leiomyoma that inhibits bone morphogenetic protein (BMP)-mediated endometrial receptivity and decidualization. Experimental. Laboratory. Women with symptomatic leiomyomas. Endometrial stromal cells (ESCs) and leiomyoma cells were isolated from surgical specimens. Leiomyoma-conditioned media (LCM) was applied to cultured ESC. The TGF-β was blocked by two approaches: TGF-β pan-specific antibody or transfection with a mutant TGF-β receptor type II. Cells were then treated with recombinant human BMP-2 to assess BMP responsiveness. Expression of BMP receptor types 1A, 1B, 2, as well as endometrial receptivity mediators HOXA10 and leukemia inhibitory factor (LIF). Enzyme-linked immunosorbent assay showed elevated TGF-β levels in LCM. LCM treatment of ESC reduced expression of BMP receptor types 1B and 2 to approximately 60% of pretreatment levels. Preincubation of LCM with TGF-β neutralizing antibody or mutant TGF receptor, but not respective controls, prevented repression of BMP receptors. HOXA10 and LIF expression was repressed in recombinant human BMP-2 treated, LCM exposed ESC. Pretreatment of LCM with TGF-β antibody or transfection with mutant TGF receptor prevented HOXA10 and LIF repression. Leiomyoma-derived TGF-β was necessary and sufficient to alter endometrial BMP-2 responsiveness. Blockade of TGF-β prevents repression of BMP-2 receptors and restores BMP-2-stimulated expression of HOXA10 and LIF. Blockade of TGF signaling is a potential strategy to improve infertility and pregnancy loss associated with uterine leiomyoma. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Evaluation of the environmental conditioning factors in the perspective of expansion of ethanol production in Brazil; Avaliacao dos condicionantes ambientais na perspectiva de expansao da producao de etanol no Brasil

Energy Technology Data Exchange (ETDEWEB)

Silva, Conceicao Elaine Cardoso

2010-03-15

Various countries have studied the possibility of adding ethanol to gasoline or using pure fuel ethanol as an alternative to petroleum derivatives. Brazil occupies a leading position in this scenario because with its National Alcohol Program (Programa Nacional do Alcool - PROALCOOL), created in 1975, it became the pioneer in setting up a biofuels program. Since then it has accumulated experience and gained mastery of the technology to produce ethanol from sugarcane. Hence there is a strong expectation that the country can become the world's main ethanol exporter. This thesis examines the main environmental impacts associated with the ethanol productive chain, which are relevant conditioning factors for the expansion of this industry in Brazil. The study describes the evolution of PROALCOOL and the overview of current structure of the brazilian sugar-alcohol sector, identifies technologies and environmental management policies, and presents the perspective of expansion of ethanol production. Thus, the study undertakes an extensive review of the literature and examines to what extent the creation and implementation of public and private environmental management policies (legal restrictions and market instruments, respectively) interfere with the expansion of these productive activities. (author)

Renormalization group and mayer expansions

International Nuclear Information System (INIS)

Mack, G.

1984-01-01

Mayer expansions promise to become a powerful tool in exact renormalization group calculations. Iterated Mayer expansions were sucessfully used in the rigorous analysis of 3-dimensional U (1) lattice gauge theory by Gopfert and the author, and it is hoped that they will also be useful in the 2-dimensional nonlinear σ-model, and elsewhere

Explaining the Expansion of Feminist Ideas: Cultural Diffusion or Political Struggle?

Science.gov (United States)

Stromquist, Nelly P.

2015-01-01

This article explores the expansion of feminist ideas as both a conceptual and a political issue. It focuses on two major theories of social change, world culture theory (WCT) and world system analysis (WSA), comparing and contrasting how they frame gender as a factor shaping society, how they account for the diffusion of feminist ideas and how…

[Ecological suitability assessment and optimization of urban land expansion space in Guiyang City].

Science.gov (United States)

Qiu, Cong-hao; Li, Yang-bing; Feng, Yuan-song

2015-09-01

Based on the case study of Guiyang City, the minimum cumulative resistance model integrating construction land source, ecological rigid constraints and ecological function type resistance factor, was built by use of cost-distance analysis of urban spatial expansion resistance value through ArcGIS 9.3 software in this paper. Then, the ecological resistance of city spatial expansion of Guiyang from 2010 was simulated dynamically and the ecological suitability classification of city spatial expansion was assessed. According to the conflict between the newly increased city construction land in 2014 and its ecological suitability, the unreasonable city land spatial allocation was discussed also. The results showed that the ecological suitability zonation and the city expansion in the study area were basically consistent during 2010-2014, but the conflict between the new city construction and its land ecological suitability was more serious. The ecological conflict area accounted for 58.2% of the new city construction sites, 35.4% of which happened in the ecological control area, 13.9% in the limited development area and 8.9% in the prohibition development area. The intensification of ecological land use conflict would impair the ecological service function and ecological safety, so this paper put forward the city spatial expansion optimal path to preserve the ecological land and improve the construction land space pattern of Guiyang City so as to ensure its ecological safety.

Asymptotic expansions for high-contrast elliptic equations

KAUST Repository

Calo, Victor M.; Efendiev, Yalchin R.; Galvis, Juan

2014-01-01

In this paper, we present a high-order expansion for elliptic equations in high-contrast media. The background conductivity is taken to be one and we assume the medium contains high (or low) conductivity inclusions. We derive an asymptotic expansion with respect to the contrast and provide a procedure to compute the terms in the expansion. The computation of the expansion does not depend on the contrast which is important for simulations. The latter allows avoiding increased mesh resolution around high conductivity features. This work is partly motivated by our earlier work in [Domain decomposition preconditioners for multiscale flows in high-contrast media, Multiscale Model Simul. 8 (2010) 1461-1483] where we design efficient numerical procedures for solving high-contrast problems. These multiscale approaches require local solutions and our proposed high-order expansion can be used to approximate these local solutions inexpensively. In the case of a large-number of inclusions, the proposed analysis can help to design localization techniques for computing the terms in the expansion. In the paper, we present a rigorous analysis of the proposed high-order expansion and estimate the remainder of it. We consider both high-and low-conductivity inclusions. © 2014 World Scientific Publishing Company.

Asymptotic expansions for high-contrast elliptic equations

KAUST Repository

Calo, Victor M.

2014-03-01

In this paper, we present a high-order expansion for elliptic equations in high-contrast media. The background conductivity is taken to be one and we assume the medium contains high (or low) conductivity inclusions. We derive an asymptotic expansion with respect to the contrast and provide a procedure to compute the terms in the expansion. The computation of the expansion does not depend on the contrast which is important for simulations. The latter allows avoiding increased mesh resolution around high conductivity features. This work is partly motivated by our earlier work in [Domain decomposition preconditioners for multiscale flows in high-contrast media, Multiscale Model Simul. 8 (2010) 1461-1483] where we design efficient numerical procedures for solving high-contrast problems. These multiscale approaches require local solutions and our proposed high-order expansion can be used to approximate these local solutions inexpensively. In the case of a large-number of inclusions, the proposed analysis can help to design localization techniques for computing the terms in the expansion. In the paper, we present a rigorous analysis of the proposed high-order expansion and estimate the remainder of it. We consider both high-and low-conductivity inclusions. © 2014 World Scientific Publishing Company.

Expansion dynamics

International Nuclear Information System (INIS)

Knoll, J.

1985-10-01

A quantum dynamical model is suggested which describes the expansion and disassembly phase of highly excited compounds formed in energetic heavy-ion collisions. First applications in two space and one time dimensional model world are discussed and qualitatively compared to standard freeze-out concepts. (orig.)

Spatial Linkage and Urban Expansion: AN Urban Agglomeration View

Science.gov (United States)

Jiao, L. M.; Tang, X.; Liu, X. P.

2017-09-01

Urban expansion displays different characteristics in each period. From the perspective of the urban agglomeration, studying the spatial and temporal characteristics of urban expansion plays an important role in understanding the complex relationship between urban expansion and network structure of urban agglomeration. We analyze urban expansion in the Yangtze River Delta Urban Agglomeration (YRD) through accessibility to and spatial interaction intensity from core cities as well as accessibility of road network. Results show that: (1) Correlation between urban expansion intensity and spatial indicators such as location and space syntax variables is remarkable and positive, while it decreases after rapid expansion. (2) Urban expansion velocity displays a positive correlation with spatial indicators mentioned above in the first (1980-1990) and second (1990-2000) period. However, it exhibits a negative relationship in the third period (2000-2010), i.e., cities located in the periphery of urban agglomeration developing more quickly. Consequently, the hypothesis of convergence of urban expansion in rapid expansion stage is put forward. (3) Results of Zipf's law and Gibrat's law show urban expansion in YRD displays a convergent trend in rapid expansion stage, small and medium-sized cities growing faster. This study shows that spatial linkage plays an important but evolving role in urban expansion within the urban agglomeration. In addition, it serves as a reference to the planning of Yangtze River Delta Urban Agglomeration and regulation of urban expansion of other urban agglomerations.

Inhibition of the Transforming Growth Factor β (TGFβ) Pathway by Interleukin-1β Is Mediated through TGFβ-activated Kinase 1 Phosphorylation of SMAD3

NARCIS (Netherlands)

Benus, G.F.J.D.; Wierenga, A.T. J.; de Gorter, D.J.J.; Schuringa, Jan-Jacob; van Bennekum, A.M.; Drenth - Diephuis, L.; Vellenga, E.; Eggen, B.J.L.

2005-01-01

Transforming growth factor β is the prototype of a large family of secreted factors that regulate multiple biological processes. In the immune system, TGFβ acts as an anti-inflammatory and immunosuppressive molecule, whereas the cytokine interleukin (IL)-1β is a crucial mediator of inflammatory

Magnetized relativistic electron-ion plasma expansion

Science.gov (United States)

Benkhelifa, El-Amine; Djebli, Mourad

2016-03-01

The dynamics of relativistic laser-produced plasma expansion across a transverse magnetic field is investigated. Based on a one dimensional two-fluid model that includes pressure, enthalpy, and rest mass energy, the expansion is studied in the limit of λD (Debye length) ≤RL (Larmor radius) for magnetized electrons and ions. Numerical investigation conducted for a quasi-neutral plasma showed that the σ parameter describing the initial plasma magnetization, and the plasma β parameter, which is the ratio of kinetic to magnetic pressure are the key parameters governing the expansion dynamics. For σ ≪ 1, ion's front shows oscillations associated to the break-down of quasi-neutrality. This is due to the strong constraining effect and confinement of the magnetic field, which acts as a retarding medium slowing the plasma expansion.

Renormalization group and Mayer expansions

International Nuclear Information System (INIS)

Mack, G.

1984-02-01

Mayer expansions promise to become a powerful tool in exact renormalization group calculations. Iterated Mayer expansions were sucessfully used in the rigorous analysis of 3-dimensional U(1) lattice gauge theory by Goepfert and the author, and it is hoped that they will also be useful in the 2-dimensional nonlinear sigma-model, and elsewhere. (orig.)

Potential impact of internet addiction and protective psychosocial factors onto depression among Hong Kong Chinese adolescents - direct, mediation and moderation effects.

Science.gov (United States)

Wu, Anise M S; Li, Jibin; Lau, Joseph T F; Mo, Phoenix K H; Lau, Mason M C

2016-10-01

Internet addiction (IA) is a risk factor while some psychosocial factors can be protective against depression among adolescents. Mechanisms of IA onto depression in terms of mediations and moderations involving protective factors are unknown and were investigated in this study. A representative cross-sectional study was conducted among Hong Kong Chinese secondary school students (n=9518). Among males and females, prevalence of depression at moderate or severe level (CES-D≥21) was 38.36% and 46.13%, and that of IA (CIAS>63) was 17.64% and 14.01%, respectively. Adjusted for socio-demographics, depression was positively associated with IA [males: adjusted odds ratio (AOR)=4.22, 95% CI=3.61-4.94; females: AOR=4.79, 95% CI=3.91-5.87] and negatively associated with psychosocial factors including self-esteem, positive affect, family support, and self-efficacy (males: AOR=0.76-0.94; females: AOR=0.72-0.92, pmoderations, IA also reduced magnitude of protective effects of self-efficacy and family support among males and that of positive affect among both sexes against depression. The high IA prevalence contributes to increased risk of prevalent depression through its direct effect, mediation (reduced level of protective factors) and moderation (reduced magnitude of protective effects) effects. Understanding to mechanisms between IA and depression through protective factors is enhanced. Screening and interventions for IA and depression are warranted, and should cultivate protective factors, and unlink negative impact of IA onto levels and effects of protective factors. Copyright © 2016. Published by Elsevier Inc.

Counterproductive Consequences of a Conservative Ideology: Medicaid Expansion and Personal Responsibility Requirements.

Science.gov (United States)

Baker, Allison M; Hunt, Linda M

2016-07-01

Medicaid expansion, a key part of the Affordable Care Act, has been opposed by conservative politicians despite its fiscal and public health benefits. In response, some Republican-led states have expanded Medicaid with new reforms, including requirements for cost sharing and behavioral incentives, that promote conservative political values tied to an ideology of personal responsibility. We examine this trend using Michigan's Medicaid expansion as a case example. We explore the origins, evidence base, and possible consequences of these reforms. We argue that these reforms prioritize ideology over sound public health knowledge, deflecting attention away from the social, economic, and structural factors that influence the health of the poor, and may ultimately contribute to counterproductive public health and fiscal outcomes.

Polyethylene Glycol Mediated Colorectal Cancer Chemoprevention: Roles of Epidermal Growth Factor Receptor and Snail

Science.gov (United States)

Wali, Ramesh K.; Kunte, Dhananjay P.; Koetsier, Jennifer L.; Bissonnette, Marc; Roy, Hemant K.

2008-01-01

Polyethylene glycol (PEG) is a clinically widely used agent with profound chemopreventive properties in experimental colon carcinogenesis. We previously reported that Snail/β-catenin signaling may mediate the suppression of epithelial proliferation by PEG, although the upstream events remain unclear. We report herein the role of epidermal growth factor receptor (EGFR), a known mediator of Snail and overepressed in ~80% of human colorectal cancers (CRC), on PEG-mediated anti-proliferative and hence anti-neoplastic effects in azoxymethane (AOM)-rats and HT-29 colon cancer cells. AOM-rats were randomized to either standard diet or one with 10% PEG 3350 and euthanized 8 weeks later. The colonic samples were subjected to immunohistochemical or Western blot analyses. PEG decreased mucosal EGFR by 60% (pPEG effects were obtained in HT-29 cells. PEG suppressed EGFR protein via lysosmal degradation with no change in mRNA levels. To show that EGFR antagonism per se was responsible for the antiproliferative effect, we inhibited EGFR by either pre-treating cells with gefitinib or stably transfecting with EGFR-shRNA and measured the effect of PEG on proliferation. In either case PEG effect was blunted suggesting a vital role of EGFR. Flow cytometric analysis revealed that EGFR-shRNA cells, besides having reduced membrane EGFR also expressed low Snail levels (40%), corroborating a strong association. Furthermore, in EGFR silenced cells PEG effect on EGFR or Snail was muted, similar to that on proliferation. In conclusion, we show that EGFR is the proximate membrane signaling molecule through which PEG initiates antiproliferative activity with Snail/β-catenin pathway playing the central intermediary function. PMID:18790788

Polyethylene glycol-mediated colorectal cancer chemoprevention: roles of epidermal growth factor receptor and Snail.

Science.gov (United States)

Wali, Ramesh K; Kunte, Dhananjay P; Koetsier, Jennifer L; Bissonnette, Marc; Roy, Hemant K

2008-09-01

Polyethylene glycol (PEG) is a clinically widely used agent with profound chemopreventive properties in experimental colon carcinogenesis. We reported previously that Snail/beta-catenin signaling may mediate the suppression of epithelial proliferation by PEG, although the upstream events remain unclear. We report herein the role of epidermal growth factor receptor (EGFR), a known mediator of Snail and overexpressed in approximately 80% of human colorectal cancers, on PEG-mediated antiproliferative and hence antineoplastic effects in azoxymethane (AOM) rats and HT-29 colon cancer cells. AOM rats were randomized to either standard diet or one with 10% PEG-3350 and euthanized 8 weeks later. The colonic samples were subjected to immunohistochemical or Western blot analyses. PEG decreased mucosal EGFR by 60% (P PEG effects were obtained in HT-29 cells. PEG suppressed EGFR protein via lysosmal degradation with no change in mRNA levels. To show that EGFR antagonism per se was responsible for the antiproliferative effect, we inhibited EGFR by either pretreating cells with gefitinib or stably transfecting with EGFR-short hairpin RNA and measured the effect of PEG on proliferation. In either case, PEG effect was blunted, suggesting a vital role of EGFR. Flow cytometric analysis revealed that EGFR-short hairpin RNA cells, besides having reduced membrane EGFR, also expressed low Snail levels (40%), corroborating a strong association. Furthermore, in EGFR silenced cells, PEG effect on EGFR or Snail was muted, similar to that on proliferation. In conclusion, we show that EGFR is the proximate membrane signaling molecule through which PEG initiates antiproliferative activity with Snail/beta-catenin pathway playing the central intermediary function.

expansion method

Indian Academy of Sciences (India)

of a system under investigation is to model the system in terms of some ... The organization of the paper is as follows: In §2, a brief account of the (G /G)- expansion ...... It is interesting to note that from the general results, one can easily recover.

Activating transcription factor 6 mediates oxidized LDL-induced cholesterol accumulation and apoptosis in macrophages by up-regulating CHOP expression.

Science.gov (United States)

Yao, Shutong; Zong, Chuanlong; Zhang, Ying; Sang, Hui; Yang, Mingfeng; Jiao, Peng; Fang, Yongqi; Yang, Nana; Song, Guohua; Qin, Shucun

2013-01-01

This study was to explore whether activating transcription factor 6 (ATF6), an important sensor to endoplasmic reticulum (ER) stress, would mediate oxidized low-density lipoprotein (ox-LDL)- induced cholesterol accumulation and apoptosis in cultured macrophages and the underlying molecular mechanisms. Intracellular lipid droplets and total cholesterol levels were assayed by oil red O staining and enzymatic colorimetry, respectively. Cell viability and apoptosis were determined using MTT assay and AnnexinV-FITC apoptosis detection kit, respectively. The nuclear translocation of ATF6 in cells was detected by immunofluorescence analysis. Protein and mRNA levels were examined by Western blot analysis and real time-PCR, respectively. ATF6 siRNA was transfected to RAW264.7 cells by lipofectamin. Exposure of cells to ox-LDL induced glucose-regulated protein 78 (GRP78). C/EBP homologous protein (CHOP), a key-signaling component of ER stress-induced apoptosis, was up-regulated in ox-LDL-treated cells. ATF6, a factor that positively regulates CHOP expression, was activated by ox-LDL in a concentration- and time- dependent manner. The role of the ATF6-mediated ER stress pathway was further confirmed through the siRNA-mediated knockdown of ATF6, which attenuated ox-LDL-induced upregulation of CHOP, cholesterol accumulation and apoptosis in macrophages. In addition, the phosphorylation of double-stranded RNA-activated protein kinase-like endoplasmic reticulum kinase (PERK), another factor that positively regulates CHOP expression, was induced in the presence of ox-LDL, and PERK-specific siRNA also inhibited the ox-LDL-induced upregulation of CHOP and apoptosis in RAW264.7 cells. These results demonstrate that ER stress-related proteins, particularly ATF6 and its downstream molecule CHOP, are involved in ox-LDL-induced cholesterol accumulation and apoptosis in macrophages.

Mediator and Cohesin Connect Gene Expression and Chromatin Architecture

Science.gov (United States)

Kagey, Michael H.; Newman, Jamie J.; Bilodeau, Steve; Zhan, Ye; Orlando, David A.; van Berkum, Nynke L.; Ebmeier, Christopher C.; Goossens, Jesse; Rahl, Peter B.; Levine, Stuart S.; Taatjes, Dylan J.; Dekker, Job; Young, Richard A.

2010-01-01

Summary Transcription factors control cell specific gene expression programs through interactions with diverse coactivators and the transcription apparatus. Gene activation may involve DNA loop formation between enhancer-bound transcription factors and the transcription apparatus at the core promoter, but this process is not well understood. We report here that Mediator and Cohesin physically and functionally connect the enhancers and core promoters of active genes in embryonic stem cells. Mediator, a transcriptional coactivator, forms a complex with Cohesin, which can form rings that connect two DNA segments. The Cohesin loading factor Nipbl is associated with Mediator/Cohesin complexes, providing a means to load Cohesin at promoters. DNA looping is observed between the enhancers and promoters occupied by Mediator and Cohesin. Mediator and Cohesin occupy different promoters in different cells, thus generating cell-type specific DNA loops linked to the gene expression program of each cell. PMID:20720539

Accelerated expansion of the universe driven by tachyonic matter

International Nuclear Information System (INIS)

Padmanabhan, T.

2002-01-01

It is an accepted practice in cosmology to invoke a scalar field with a potential V(φ) when the observed evolution of the universe cannot be reconciled with theoretical prejudices. Since one function degree of freedom in the expansion factor a(t) can be traded off for the function V(φ), it is always possible to find a scalar field potential which will reproduce a given evolution. I provide a recipe for determining V(φ) from a(t) in two cases: (i) a normal scalar field with the Lagrangian L=(1/2)∂ a φ∂ a φ-V(φ) used in quintessence or dark energy models; (ii) a tachyonic field with the Lagrangian L=-V(φ)[1-∂ a φ∂ a φ] 1/2 , motivated by recent string theoretic results. In the latter case, it is possible to have accelerated expansion of the universe during the late phase in certain cases

Expansion of Tubular with Elastomers in Multilateral Wells

Directory of Open Access Journals (Sweden)

Md Velden

2013-06-01

Full Text Available The use of solid expandable tubular technology during the last decade has focused on solving many challenges in well drilling and delivery including zonal isolation, deep drilling, conservation of hole sizes, etc. not only as pioneered solution but also providing cost effective and long lasting solutions. Concurrently, the technology was extended for construction of multilateral in typical wells. The process of horizontal tubular expansion is similar to the vertical expansion of expandable tubular in down-hole environment with the addition of uniformly distributed force due to its weight. The expansion is targeted to increase its diameter such that post expansion characteristics remain within allowable limits. In this study a typical expandable tubular of 57.15 mm outer diameter and 6.35 mm wall thickness was used with two different elastomer seals of 5 and 7 mm thickness placed at equal spacing of 200 mm. The developed stress contours during expansion process clearly showed the high stress areas in the vicinity of expansion region which lies around the mandrel. These high stresses may result in excessive wear of the mandrel. It was also found out that the drawing force increases as the mandrel angle, expansion ratio, and friction coefficient increases. A mandrel angle of 20o  requires minimum expansion force and can be considered as an optimum geometrical parameter to lower the power required for expansion.

Role of 5′TG3′-interacting factors (TGIFs) in Vorinostat (HDAC inhibitor)-mediated Corneal Fibrosis Inhibition

Science.gov (United States)

Sharma, Ajay; Sinha, Nishant R.; Siddiqui, Saad

2015-01-01

Purpose We have previously reported that vorinostat, an FDA-approved, clinically used histone deacetylase (HDAC) inhibitor, attenuates corneal fibrosis in vivo in rabbits by blocking transforming growth factor β (TGFβ). The 5′TG3′-interacting factors (TGIFs) are transcriptional repressors of TGFβ1 signaling via the Smad pathway. The present study was designed to explore the expression of TGIFs in human corneal fibroblasts and to investigate their role in mediating the antifibrotic effect of vorinostat. Methods Human corneal fibroblast cultures were generated from donor corneas. RNA isolation, cDNA preparation, and PCR were performed to detect the presence of TGIF1 and TGIF2 transcripts. The cultures were exposed to vorinostat (2.5 µM) to test its effect on TGIF mRNA and protein levels using qPCR and immunoblotting. Myofibroblast formation was induced with TGFβ1 (5 ng/ml) treatment under serum-free conditions. The changes in fibrosis parameters were quantified by measuring fibrosis marker α-smooth muscle actin (αSMA) mRNA and protein levels with qPCR, immunostaining, and immunoblotting. Smad2/3/4 and TGIF knockdowns were performed using pre-validated RNAi/siRNAs and a commercially available transfection reagent. Results Human corneal fibroblasts showed the expression of TGIF1 and TGIF2. Vorinostat (2.5 µM) caused a 2.8–3.3-fold increase in TGIF1 and TGIF2 mRNA levels and a 1.4–1.8-fold increase in TGIF1 and TGIF2 protein levels. Vorinostat treatment also caused a significant increase in acetylhistone H3 and acetylhistone H4. Vorinostat-induced increases in TGIF1 and TGIF2 were accompanied by a concurrent decrease in corneal fibrosis, as indicated by a decrease in αSMA mRNA by 83±7.7% and protein levels by 97±5%. The RNAi-mediated knockdown of Smad2, Smad3, and Smad4 markedly attenuated TGFβ1-evoked transdifferentiation of fibroblasts to myofibroblasts. The siRNA-mediated knockdown of TGIF1 and TGIF2 neutralized vorinostat-evoked decreases in �

Stress and multiple sclerosis: A systematic review considering potential moderating and mediating factors and methods of assessing stress

Directory of Open Access Journals (Sweden)

Laia Briones-Buixassa

2015-11-01

Full Text Available Research about the effects of stress on multiple sclerosis has yielded contradictory results. This study aims to systematically review the evidence focusing on two possible causes: the role of stress assessment and potential moderating and mediating factors. The Web of Knowledge (MEDLINE and Web of Science, Scopus, and PsycINFO databases were searched for relevant articles published from 1900 through December 2014 using the terms “stress*” AND “multiple sclerosis.” Twenty-three articles were included. Studies focused on the effect of stress on multiple sclerosis onset ( n  = 9 were mostly retrospective, and semi-structured interviews and scales yielded the most consistent associations. Studies focused on multiple sclerosis progression ( n  = 14 were mostly prospective, and self-reported diaries yielded the most consistent results. The most important modifying factors were stressor duration, severity, and frequency; cardiovascular reactivity and heart rate; and social support and escitalopram intake. Future studies should consider the use of prospective design with self-reported evaluations and the study of moderators and mediators related to amount of stress and autonomic nervous system reactivity to determine the effects of stress on multiple sclerosis.

Stress and multiple sclerosis: A systematic review considering potential moderating and mediating factors and methods of assessing stress.

Science.gov (United States)

Briones-Buixassa, Laia; Milà, Raimon; Mª Aragonès, Josep; Bufill, Enric; Olaya, Beatriz; Arrufat, Francesc Xavier

2015-07-01

Research about the effects of stress on multiple sclerosis has yielded contradictory results. This study aims to systematically review the evidence focusing on two possible causes: the role of stress assessment and potential moderating and mediating factors. The Web of Knowledge (MEDLINE and Web of Science), Scopus, and PsycINFO databases were searched for relevant articles published from 1900 through December 2014 using the terms "stress*" AND "multiple sclerosis." Twenty-three articles were included. Studies focused on the effect of stress on multiple sclerosis onset ( n  = 9) were mostly retrospective, and semi-structured interviews and scales yielded the most consistent associations. Studies focused on multiple sclerosis progression ( n  = 14) were mostly prospective, and self-reported diaries yielded the most consistent results. The most important modifying factors were stressor duration, severity, and frequency; cardiovascular reactivity and heart rate; and social support and escitalopram intake. Future studies should consider the use of prospective design with self-reported evaluations and the study of moderators and mediators related to amount of stress and autonomic nervous system reactivity to determine the effects of stress on multiple sclerosis.

Diphtheria toxin- and Pseudomonas A toxin-mediated apoptosis. ADP ribosylation of elongation factor-2 is required for DNA fragmentation and cell lysis and synergy with tumor necrosis factor-alpha.

Science.gov (United States)

Morimoto, H; Bonavida, B

1992-09-15

We have reported that diphtheria toxin (DTX) mediates target cell lysis and intranucleosomal DNA fragmentation (apoptosis) and also synergizes with TNF-alpha. In this paper, we examined which step in the pathway of DTX-mediated inhibition of protein synthesis was important for induction of cytolytic activity and for synergy. Using a DTX-sensitive tumor cell line, we first examined the activity of the mutant CRM 197, which does not catalyze the ADP ribosylation of elongation factor-2 (EF-2). CRM 197 was not cytolytic for target cells and did not mediate intranucleosomal DNA fragmentation of viable cells. The failure of CRM 197 to mediate target cell lysis suggested that the catalytic activity of DTX is prerequisite for target cell lysis. This was corroborated by demonstrating that MeSAdo, which blocks the biosynthesis of diphthamide, inhibited DTX-mediated protein synthesis inhibition and also blocked target cell lysis. Furthermore, the addition of nicotinamide, which competes with NAD+ on the DTX action site of EF-2, also blocked DTX-mediated lysis. These findings suggest that ADP-ribosylation of EF-2 may be a necessary step in the pathway leading to target cell lysis. In contrast to the sensitive line, the SKOV-3 tumor cell line is sensitive to protein synthesis inhibition by DTX but is not susceptible to cytolysis and apoptosis by DTX. Thus, protein synthesis inhibition by DTX is not sufficient to mediate target cell lysis. The synergy in cytotoxicity obtained with the combination of DTX and TNF-alpha was examined in order to determine the pathway mediated by DTX in synergy. Like the direct lysis by DTX, synergy was significantly reduced by MeSAdo and by nicotinamide. Furthermore, synergy was not observed with combination of CRM 197 and TNF-alpha. These results demonstrate that, in synergy, DTX may utilize the same pathway required for its cytolytic activity. Pseudomonas aeruginosa exotoxin shared most the properties shown for DTX. Altogether, these findings

Beta-elemene blocks epithelial-mesenchymal transition in human breast cancer cell line MCF-7 through Smad3-mediated down-regulation of nuclear transcription factors.

Directory of Open Access Journals (Sweden)

Xian Zhang

Full Text Available Epithelial-mesenchymal transition (EMT is the first step required for breast cancer to initiate metastasis. However, the potential of drugs to block and reverse the EMT process are not well explored. In the present study, we investigated the inhibitory effect of beta-elemene (ELE, an active component of a natural plant-derived anti-neoplastic agent in an established EMT model mediated by transforming growth factor-beta1 (TGF-β1. We found that ELE (40 µg/ml blocked the TGF-β1-induced phenotypic transition in the human breast cancer cell line MCF-7. ELE was able to inhibit TGF-β1-mediated upregulation of mRNA and protein expression of nuclear transcription factors (SNAI1, SNAI2, TWIST and SIP1, potentially through decreasing the expression and phosphorylation of Smad3, a central protein mediating the TGF-β1 signalling pathway. These findings suggest a potential therapeutic benefit of ELE in treating basal-like breast cancer.

Adiabatic supernova expansion into the circumstellar medium

International Nuclear Information System (INIS)

Band, D.L.; Liang, E.P.

1987-01-01

We perform one dimensional numerical simulations with a Lagrangian hydrodynamics code of the adiabatic expansion of a supernova into the surrounding medium. The early expansion follows Chevalier's analytic self-similar solution until the reverse shock reaches the ejecta core. We follow the expansion as it evolves towards the adiabatic blast wave phase. Some memory of the earlier phases of expansion is retained in the interior even when the outer regions expand as a blast wave. We find the results are sensitive to the initial configuration of the ejecta and to the placement of gridpoints. 6 refs., 2 figs

Upregulation of the coagulation factor VII gene during glucose deprivation is mediated by activating transcription factor 4.

Directory of Open Access Journals (Sweden)

Katherine R Cronin

Full Text Available BACKGROUND: Constitutive production of blood coagulation proteins by hepatocytes is necessary for hemostasis. Stressful conditions trigger adaptive cellular responses and delay processing of most proteins, potentially affecting plasma levels of proteins secreted exclusively by hepatocytes. We examined the effect of glucose deprivation on expression of coagulation proteins by the human hepatoma cell line, HepG2. METHODOLOGY/PRINCIPAL FINDINGS: Expression of coagulation factor VII, which is required for initiation of blood coagulation, was elevated by glucose deprivation, while expression of other coagulation proteins decreased. Realtime PCR and ELISA demonstrated that the relative percentage expression +/- SD of steady-state F7 mRNA and secreted factor VII antigen were significantly increased (from 100+/-15% to 188+/-27% and 100+/-8.8% to 176.3+/-17.3% respectively, p<0.001 at 24 hr of treatment. The integrated stress response was induced, as indicated by upregulation of transcription factor ATF4 and of additional stress-responsive genes. Small interfering RNAs directed against ATF4 potently reduced basal F7 expression, and prevented F7 upregulation by glucose deprivation. The response of the endogenous F7 gene was replicated in reporter gene assays, which further indicated that ATF4 effects were mediated via interaction with an amino acid response element in the F7 promoter. CONCLUSIONS/SIGNIFICANCE: Our data indicated that glucose deprivation enhanced F7 expression in a mechanism reliant on prior ATF4 upregulation primarily due to increased transcription from the ATF4 gene. Of five coagulation protein genes examined, only F7 was upregulated, suggesting that its functions may be important in a systemic response to glucose deprivation stress.

Decennial plan of expansion 1994-2003

International Nuclear Information System (INIS)

1993-12-01

The Decennial Plan of Expansion 1994-2003 of Electric sector reproduces the results of the studies occurred during the planning cycle of 1992/93 from the Coordinator Groups of the Electric System Planning. Based in the market forecasting, economic-financier and time for finishing the the works, the Decennial Plan of Expansion presents the schedule of the main generation and transmission works for the next ten years, the annual spend in generation, transmission and distribution, the costs of expansion and the evaluation of attending conditions in electric system in Brazil. (C.G.C.)

Mediating Factors Explaining the Association Between Sexual Minority Status and Dating Violence.

Science.gov (United States)

Martin-Storey, Alexa; Fromme, Kim

2017-08-01

Dating violence presents a serious threat for individual health and well-being. A growing body of literature suggests that starting in adolescence, individuals with sexual minority identities (e.g., individuals who identify as gay, lesbian, or bisexual) may be at an increased risk for dating violence compared with heterosexuals. Research has not, however, identified the mechanisms that explain this vulnerability. Using a diverse sample of young adults ( n = 2,474), the current study explored how minority stress theory, revictimization theory, sex of sexual partners, and risky sexual behavior explained differences in dating violence between sexual minority and heterosexual young adults. Initial analyses suggested higher rates of dating violence among individuals who identified as bisexual, and individuals who identified as gay or lesbian when compared with heterosexuals, and further found that these associations failed to differ across gender. When mediating and control variables were included in the analyses, however, the association between both sexual minority identities and higher levels of dating violence became nonsignificant. Of particular interest was the role of discrimination, which mediated the association between bisexual identity and dating violence. Other factors, including sex and number of sexual partners, alcohol use, and childhood maltreatment, were associated with higher rates of dating violence but did not significantly explain vulnerability among sexual minority individuals compared with their heterosexual peers. These findings suggest the importance of minority stress theory in explaining vulnerability to dating violence victimization among bisexuals in particular, and generally support the importance of sexual-minority specific variables in understanding risk for dating violence within this vulnerable population.

In vitro evaluation of force-expansion characteristics in a newly designed orthodontic expansion screw compared to conventional screws

Directory of Open Access Journals (Sweden)

Oshagh Morteza

2009-01-01

Full Text Available Objective : Expansion screws like Hyrax, Haas and other types, produce heavy interrupted forces which are unfavorable for dental movement and could be harmful to the tooth and periodontium. The other disadvantage of these screws is the need for patient cooperation for their regular activation. The purpose of this study was to design a screw and compare its force- expansion curve with other types. Materials and Methods : A new screw was designed and fabricated in the same dimension, with conventional types, with the ability of 8 mm expansion (Free wire length: 12 mm, initial compression: 4.5 mm, spring wire diameter: 0.4 mm, spring diameter: 3 mm, number of the coils: n0 ine, material: s0 tainless steel. In this in vitro study, the new screw was placed in an acrylic orthodontic appliance, and after mounting on a stone cast, the force-expansion curve was evaluated by a compression test machine and compared to other screws. Results : Force-expansion curve of designed screw had a flatter inclination compared to other screws. Generally it produced a light continuous force (two to 3.5 pounds for every 4 mm of expansion. Conclusion : In comparison with heavy and interrupted forces of other screws, the newly designed screw created light and continuous forces.

Components of Cigarette Smoke Inhibit Expansion of Oocyte-Cumulus Comlexes from Porcine Follicles

Czech Academy of Sciences Publication Activity Database

Vršanská, S.; Nagyová, Eva; Mlynarčíková, A.; Ficková, M.; Kolena, J.

2003-01-01

Roč. 52, č. 3 (2003), s. 383-387 ISSN 0862-8408 R&D Projects: GA AV ČR IAA5045102 Institutional research plan: CEZ:AV0Z5045916 Keywords : porcine ovary * cigarette alkaloids * cumulus expansion Subject RIV: ED - Physiology Impact factor: 0.939, year: 2003

Financing electricity expansion

International Nuclear Information System (INIS)

Hyman, L.S.

1994-01-01

Expansion of electricity supply is associated with economic development. The installation and enlargement of power systems in developing countries entails a huge financial burden, however. Energy consumers in such countries must pay not only for supplies but for the cost of raising the capital for expansion on the international markets. Estimates are presented for the capital expenditure for electricity supply over the period 1990 to 2020 for the major world regions, using approximations for the cost of plant and capital and for the returns earned. These data lead to the conclusion that the five regions with the lowest per capita incomes are those which will need the major part of the capital expenditure and the highest percentage of external finance. (6 tables) (UK)

Preparation of Shrinkage Compensating Concrete with HCSA Expansive Agent

Science.gov (United States)

Li, Changcheng; Jia, Fujia

2017-10-01

Shrinkage compensating concrete (SCC) has become one of the best effective methods of preventing and reducing concrete cracking. SCC is prepared by HCSA high performance expansive agent for concrete which restrained expansion rate is optimized by 0.057%. Slump, compressive strength, restrained expansion rate and cracking resistance test were carried out on SCC. The results show that the initial slump of fresh SCC was about 220mm-230mm, while slump after 2 hours was 180mm-200mm. The restrained expansion rate of SCC increased with the mixing amount of expansive agent. After cured in water for 14 days, the restrained expansion rate of C35 and C40 SCC were 0.020%-0.032%. With the dosage of expansive agent increasing, restrained expansion rate of SCC increased, maximum compressive stress and cracking stress improved, cracking temperature fell, thus cracking resistance got effectively improvement.

Strategic environmental assessment for sustainable expansion of palm oil biofuels in Brazilian north region

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Carolina

2010-09-15

Biofuels development in Brazil is a key factor for the environment and sustainable development of the country. Brazil has great potential of available areas and has favourable climate and geography for biofuel production, such as palm oil, soy, sugar cane, etc. This research aims to evaluate palm oil production and expansion in Para state, in the north of Brazil and also Amazonian territory. Degraded land will be evaluated through remote sensing, because palm oil crops should be placed in these lands, and secondly, expansion scenarios would be created. This PhD research will be a decision support tool for public policies.

PPARγ ligand production is tightly linked to clonal expansion during initiation of adipocyte differentiation

DEFF Research Database (Denmark)

Hallenborg, Philip; Petersen, Rasmus Koefoed; Feddersen, Søren

2014-01-01

of differentiation. Concomitant with agonist production, murine fibroblasts undergo two rounds of mitosis referred to as mitotic clonal expansion. Here we show that mouse embryonic fibroblasts deficient in either of two cell cycle inhibitors, the transcription factor p53 or its target gene encoding the cyclin...... cycle inhibitory compounds decreased PPAR ligand production in differentiating 3T3-L1 preadipocytes. Furthermore, these inhibitors abolished the release of arachidonic acid induced by the hormonal cocktail initiating adipogenesis. Collectively, our results suggest that murine fibroblasts require clonal...... expansion for PPAR ligand production at the onset of adipocyte differentiation....

Use of expansion joints in power stations

International Nuclear Information System (INIS)

Birker; Rommerswinkel.

1976-01-01

The paper discusses the mode of action of different systems of expansion joints. Special regard is given to the problems of expansion of pipelines of high rated diameter as employed in today's large power plant turbines. Due to the limited space available, the important role of the spring rate of the bellows for the reaction forces and moments acting on the connection points is pointed out. Apart from this details are given on the fabrication and materials selection of expansion joint bellows, and problems are discussed which arise in connection with the mechanical or hydraulic deformation of bellows with one or more walls. The non-destructive methods now in use for the testing of expansion pipe joints are mentioned along with experiments to test their behaviour under changing loads. The paper concludes on some remarks concerning proper transport, storage and installation of expansion pipe joints. (orig./AK) [de

MiR-17/20/93/106 promote hematopoietic cell expansion by targeting sequestosome 1–regulated pathways in mice

Science.gov (United States)

Meenhuis, Annemarie; van Veelen, Peter A.; de Looper, Hans; van Boxtel, Nicole; van den Berge, Iris J.; Sun, Su M.; Taskesen, Erdogan; Stern, Patrick; de Ru, Arnoud H.; van Adrichem, Arjan J.; Demmers, Jeroen; Jongen-Lavrencic, Mojca; Löwenberg, Bob; Touw, Ivo P.; Sharp, Phillip A.

2011-01-01

MicroRNAs (miRNAs) are pivotal for regulation of hematopoiesis but their critical targets remain largely unknown. Here, we show that ectopic expression of miR-17, -20,-93 and -106, all AAAGUGC seed-containing miRNAs, increases proliferation, colony outgrowth and replating capacity of myeloid progenitors and results in enhanced P-ERK levels. We found that these miRNAs are endogenously and abundantly expressed in myeloid progenitors and down-regulated in mature neutrophils. Quantitative proteomics identified sequestosome 1 (SQSTM1), an ubiquitin-binding protein and regulator of autophagy-mediated protein degradation, as a major target for these miRNAs in myeloid progenitors. In addition, we found increased expression of Sqstm1 transcripts during CSF3-induced neutrophil differentiation of 32D-CSF3R cells and an inverse correlation of SQSTM1 protein levels and miR-106 expression in AML samples. ShRNA-mediated silencing of Sqstm1 phenocopied the effects of ectopic miR-17/20/93/106 expression in hematopoietic progenitors in vitro and in mice. Further, SQSTM1 binds to the ligand-activated colony-stimulating factor 3 receptor (CSF3R) mainly in the late endosomal compartment, but not in LC3 positive autophagosomes. SQSTM1 regulates CSF3R stability and ligand-induced mitogen-activated protein kinase signaling. We demonstrate that AAAGUGC seed-containing miRNAs promote cell expansion, replating capacity and signaling in hematopoietic cells by interference with SQSTM1-regulated pathways. PMID:21628417

Cosmic expansion and growth histories in Galileon scalar-tensor models of dark energy

International Nuclear Information System (INIS)

Kobayashi, Tsutomu

2010-01-01

We study models of late-time cosmic acceleration in terms of scalar-tensor theories generalized to include a certain class of nonlinear derivative interaction of the scalar field. The nonlinear effect suppresses the scalar-mediated force at short distances to pass solar-system tests of gravity. It is found that the expansion history until today is almost indistinguishable from that of the ΛCDM model or some (phantom) dark energy models, but the fate of the universe depends clearly on the model parameter. The growth index of matter density perturbations is computed to show that its past asymptotic value is given by 9/16, while the value today is as small as 0.4.

Impact of socio-demographic factors on the mitigating actions for climate change: a path analysis with mediating effects of attitudinal variables.

Science.gov (United States)

Masud, Muhammad Mehedi; Akhatr, Rulia; Nasrin, Shamima; Adamu, Ibrahim Mohammed

2017-12-01

Socio-demographic factors play a significant role in increasing the individual's climate change awareness and in setting a favorable individual attitude towards its mitigation. To better understand how the adversative effects of climate change can be mitigated, this study attempts to investigate the impact of socio-demographic factors on the mitigating actions of the individuals (MAOI) on climate change. Qualitative data were collected from a face-to-face survey of 360 respondents in the Kuala Lumpur region of Malaysia through a close-ended questionnaire. Analysis was conducted on the mediating effects of attitudinal variables through the path model by using the SEM. Findings indicate that the socio-demographic factors such as gender, age, education, income, and ethnicity can greatly influence the individual's awareness, attitude, risk perception, and knowledge of climate change issues. The results drawn from this study also revealed that the attitudinal factors act as a mediating effect between the socio-demographic factors and the MAOI, thereby, indicating that both the socio-demographic factors and the attitudinal factors have significant effects on the MAOI towards climate change. The outcome of this study can help policy makers and other private organizations to decide on the appropriate actions to take in managing climate change effects. These actions which encompass improving basic climate change education and making the public more aware of the local dimensions of climate change are important for harnessing public engagement and support that can also stimulate climate change awareness and promote mitigating actions to n protect the environment from the impact of climate change.

Chromatic Derivatives, Chromatic Expansions and Associated Spaces

OpenAIRE

Ignjatovic, Aleksandar

2009-01-01

This paper presents the basic properties of chromatic derivatives and chromatic expansions and provides an appropriate motivation for introducing these notions. Chromatic derivatives are special, numerically robust linear differential operators which correspond to certain families of orthogonal polynomials. Chromatic expansions are series of the corresponding special functions, which possess the best features of both the Taylor and the Shannon expansions. This makes chromatic derivatives and ...

Warp drive with zero expansion

Energy Technology Data Exchange (ETDEWEB)

Natario, Jose [Department of Mathematics, Instituto Superior Tecnico (Portugal)

2002-03-21

It is commonly believed that Alcubierre's warp drive works by contracting space in front of the warp bubble and expanding the space behind it. We show that this contraction/expansion is but a marginal consequence of the choice made by Alcubierre and explicitly construct a similar spacetime where no contraction/expansion occurs. Global and optical properties of warp-drive spacetimes are also discussed.

IL-13-induced proliferation of airway epithelial cells: mediation by intracellular growth factor mobilization and ADAM17

Directory of Open Access Journals (Sweden)

Sandifer Tracy

2007-07-01

Full Text Available Abstract Background The pleiotrophic cytokine interleukin (IL-13 features prominently in allergic and inflammatory diseases. In allergic asthma, IL-13 is well established as an inducer of airway inflammation and tissue remodeling. We demonstrated previously that IL-13 induces release of transforming growth factor-α (TGFα from human bronchial epithelial cells, with proliferation of these cells mediated by the autocrine/paracrine action of this growth factor. TGFα exists as an integral membrane protein and requires proteolytic processing to its mature form, with a disintegrin and metalloproteinase (ADAM17 responsible for this processing in a variety of tissues. Methods In this study, normal human bronchial epithelial (NHBE cells grown in air/liquid interface (ALI culture were used to examine the mechanisms whereby IL-13 induces release of TGFα and cellular proliferation. Inhibitors and antisense RNA were used to examine the role of ADAM17 in these processes, while IL-13-induced changes in the intracellular expression of TGFα and ADAM17 were visualized by confocal microscopy. Results IL-13 was found to induce proliferation of NHBE cells, and release of TGFα, in an ADAM17-dependent manner; however, this IL-13-induced proliferation did not appear to result solely from ADAM17 activation. Rather, IL-13 induced a change in the location of TGFα expression from intracellular to apical regions of the NHBE cells. The apical region was also found to be a site of significant ADAM17 expression, even prior to IL-13 stimulation. Conclusion Results from this study indicate that ADAM17 mediates IL-13-induced proliferation and TGFα shedding in NHBE cells. Furthermore, they provide the first example wherein a cytokine (IL-13 induces a change in the intracellular expression pattern of a growth factor, apparently inducing redistribution of intracellular stores of TGFα to the apical region of NHBE cells where expression of ADAM17 is prominent. Thus, IL-13

Molecular functions of the LIM-homeobox transcription factor Lhx2 in hematopoietic progenitor cells derived from mouse embryonic stem cells.

Science.gov (United States)

Kitajima, Kenji; Kawaguchi, Manami; Iacovino, Michelina; Kyba, Michael; Hara, Takahiko

2013-12-01

We previously demonstrated that hematopoietic stem cell (HSC)-like cells are robustly expanded from mouse embryonic stem cells (ESCs) by enforced expression of Lhx2, a LIM-homeobox domain (LIM-HD) transcription factor. In this study, we analyzed the functions of Lhx2 in that process using an ESC line harboring an inducible Lhx2 gene cassette. When ESCs are cultured on OP9 stromal cells, hematopoietic progenitor cells (HPCs) are differentiated and these HPCs are prone to undergo rapid differentiation into mature hematopoietic cells. Lhx2 inhibited differentiation of HPCs into mature hematopoietic cells and this effect would lead to accumulation of HSC-like cells. LIM-HD factors interact with LIM domain binding (Ldb) protein and this interaction abrogates binding of LIM-only (Lmo) protein to Ldb. We found that one of Lmo protein, Lmo2, was unstable due to dissociation of Lmo2 from Ldb1 in the presence of Lhx2. This effect of Lhx2 on the amount of Lmo2 contributed into accumulation of HSC-like cells, since enforced expression of Lmo2 into HSC-like cells inhibited their self-renewal. Expression of Gata3 and Tal1/Scl was increased in HSC-like cells and enforced expression of Lmo2 reduced expression of Gata3 but not Tal1/Scl. Enforced expression of Gata3 into HPCs inhibited mature hematopoietic cell differentiation, whereas Gata3-knockdown abrogated the Lhx2-mediated expansion of HPCs. We propose that multiple transcription factors/cofactors are involved in the Lhx2-mediated expansion of HSC-like cells from ESCs. Lhx2 appears to fine-tune the balance between self-renewal and differentiation of HSC-like cells. © AlphaMed Press.

Human trophoblast survival at low oxygen concentrations requires metalloproteinase-mediated shedding of heparin-binding EGF-like growth factor.

Science.gov (United States)

Armant, D Randall; Kilburn, Brian A; Petkova, Anelia; Edwin, Samuel S; Duniec-Dmuchowski, Zophia M; Edwards, Holly J; Romero, Roberto; Leach, Richard E

2006-02-01

Heparin-binding EGF-like growth factor (HBEGF), which is expressed in the placenta during normal pregnancy, is down regulated in pre-eclampsia, a human pregnancy disorder associated with poor trophoblast differentiation and survival. This growth factor protects against apoptosis during stress, suggesting a role in trophoblast survival in the relatively low O(2) ( approximately 2%) environment of the first trimester conceptus. Using a well-characterized human first trimester cytotrophoblast cell line, we found that a 4-hour exposure to 2% O(2) upregulates HBEGF synthesis and secretion independently of an increase in its mRNA. Five other expressed members of the EGF family are largely unaffected. At 2% O(2), signaling via HER1 or HER4, known HBEGF receptors, is required for both HBEGF upregulation and protection against apoptosis. This positive-feedback loop is dependent on metalloproteinase-mediated cleavage and shedding of the HBEGF ectodomain. The restoration of trophoblast survival by the addition of soluble HBEGF in cultures exposed to low O(2) and metalloproteinase inhibitor suggests that the effects of HBEGF are mediated by autocrine/paracrine, rather than juxtacrine, signaling. Our results provide evidence that a post-transcriptional mechanism induced in trophoblasts by low O(2) rapidly amplifies HBEGF signaling to inhibit apoptosis. These findings have a high clinical significance, as the downregulation of HBEGF in pre-eclampsia is likely to be a contributing factor leading to the demise of trophoblasts.

Complement-mediated bactericidal activity of anti-factor H binding protein monoclonal antibodies against the meningococcus relies upon blocking factor H binding.

Science.gov (United States)

Giuntini, Serena; Reason, Donald C; Granoff, Dan M

2011-09-01

Binding of the complement-downregulating protein factor H (fH) to the surface of the meningococcus is important for survival of the organism in human serum. The meningococcal vaccine candidate factor H binding protein (fHbp) is an important ligand for human fH. While some fHbp-specific monoclonal antibodies (MAbs) block binding of fH to fHbp, the stoichiometry of blocking in the presence of high serum concentrations of fH and its effect on complement-mediated bactericidal activity are unknown. To investigate this question, we constructed chimeric antibodies in which the human IgG1 constant region was paired with three murine fHbp-specific binding domains designated JAR 3, JAR 5, and MAb502. By surface plasmon resonance, the association rates for binding of all three MAbs to immobilized fHbp were >50-fold higher than that for binding of fH to fHbp, and the MAb dissociation rates were >500-fold lower than that for fH. While all three MAbs elicited similar C1q-dependent C4b deposition on live bacteria (classical complement pathway), only those antibodies that inhibited binding of fH to fHbp (JAR 3 and JAR 5) had bactericidal activity with human complement. MAb502, which did not inhibit fH binding, had complement-mediated bactericidal activity only when tested with fH-depleted human complement. When an IgG1 anti-fHbp MAb binds to sparsely exposed fHbp on the bacterial surface, there appears to be insufficient complement activation for bacteriolysis unless fH binding also is inhibited. The ability of fHbp vaccines to elicit protective antibodies, therefore, is likely to be enhanced if the antibody repertoire is of high avidity and includes fH-blocking activity.

Magnetic Nulls and Super-radial Expansion in the Solar Corona

Energy Technology Data Exchange (ETDEWEB)

Gibson, Sarah E.; Dalmasse, Kevin; Tomczyk, Steven; Toma, Giuliana de; Burkepile, Joan; Galloy, Michael [National Center for Atmospheric Research, 3080 Center Green Drive, Boulder, CO 80301 (United States); Rachmeler, Laurel A. [NASA Marshall Space Flight Center, Huntsville, AL 35811 (United States); Rosa, Marc L. De, E-mail: sgibson@ucar.edu [Lockheed Martin Solar and Astrophysics Laboratory, 3251 Hanover Street B/252, Palo Alto, CA 94304 (United States)

2017-05-10

Magnetic fields in the Sun’s outer atmosphere—the corona—control both solar-wind acceleration and the dynamics of solar eruptions. We present the first clear observational evidence of coronal magnetic nulls in off-limb linearly polarized observations of pseudostreamers, taken by the Coronal Multichannel Polarimeter (CoMP) telescope. These nulls represent regions where magnetic reconnection is likely to act as a catalyst for solar activity. CoMP linear-polarization observations also provide an independent, coronal proxy for magnetic expansion into the solar wind, a quantity often used to parameterize and predict the solar wind speed at Earth. We introduce a new method for explicitly calculating expansion factors from CoMP coronal linear-polarization observations, which does not require photospheric extrapolations. We conclude that linearly polarized light is a powerful new diagnostic of critical coronal magnetic topologies and the expanding magnetic flux tubes that channel the solar wind.

Dynamic modelling of the expansion cylinder of an open Joule cycle Ericsson engine: A bond graph approach

International Nuclear Information System (INIS)

Creyx, M.; Delacourt, E.; Morin, C.; Desmet, B.

2016-01-01

A dynamic model using the bond graph formalism of the expansion cylinder of an open Joule cycle Ericsson engine intended for a biomass-fuelled micro-CHP system is presented. Dynamic phenomena, such as the thermodynamic evolution of air, the instantaneous air mass flow rates linked to pressure drops crossing the valves, the heat transferred through the expansion cylinder wall and the mechanical friction losses, are included in the model. The influence on the Ericsson engine performances of the main operating conditions (intake air pressure and temperature, timing of intake and exhaust valve closing, rotational speed, mechanical friction losses and heat transfer at expansion cylinder wall) is studied. The operating conditions maximizing the performances of the Ericsson engine used in the a biomass-fuelled micro-CHP unit are an intake air pressure between 6 and 8 bar, a maximized intake air temperature, an adjustment of the intake and exhaust valve closing corresponding to an expansion cycle close to the theoretical Joule cycle, a rotational speed close to 800 rpm. The heat transfer at the expansion cylinder wall reduces the engine performances. - Highlights: • A bond graph dynamic model of the Ericsson engine expansion cylinder is presented. • Dynamic aspects are modelled: pressure drops, friction losses, wall heat transfer. • Influent factors and phenomena on the engine performances are investigated. • Expansion cycles close to the theoretical Joule cycle maximize the performances. • The heat transfer at the expansion chamber wall reduces the performances.

The δ expansion for stochastic quantization

International Nuclear Information System (INIS)

Bender, C.M.; Cooper, F.; Milton, K.A.; Department of Physics, Brown University, Providence, Rhode Island 02912; Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexic o 87545; Department of Physics, The Ohio State University, Columbus, Ohio 43210; Department of Physics and Astronomy, University of Oklahoma, Norman, Oklaho ma 73019)

1989-01-01

Using a recently proposed perturbation expansion called the δ expansion, we show how to solve the Langevin equation associated with a gphi 4 field theory. We illustrate the technique in zero- and one-dimensional space-time, and then generalize this approach to d dimensions

Considering FACTS in Optimal Transmission Expansion Planning

Directory of Open Access Journals (Sweden)

K. Soleimani

2017-10-01

Full Text Available The expansion of power transmission systems is an important part of the expansion of power systems that requires enormous investment costs. Since the construction of new transmission lines is very expensive, it is necessary to choose the most efficient expansion plan that ensures system security with a minimal number of new lines. In this paper, the role of Flexible AC Transmission System (FACTS devices in the effective operation and expansion planning of transmission systems is examined. Effort was taken to implement a method based on sensitivity analysis to select the optimal number and location of FACTS devices, lines and other elements of the transmission system. Using this method, the transmission expansion plan for a 9 and a 39 bus power system was performed with and without the presence of FACTS with the use of DPL environment in Digsilent software 15.1. Results show that the use of these devices reduces the need for new transmission lines and minimizes the investment cost.

Expansion and Brightness Changes in the Pulsar-wind Nebula in the Composite Supernova Remnant Kes 75

Science.gov (United States)

Reynolds, Stephen P.; Borkowski, Kazimierz J.; Gwynne, Peter H.

2018-04-01

We report new Chandra X-ray observations of the shell supernova remnant Kes 75 (G29.7‑0.3) containing a pulsar and pulsar-wind nebula (PWN). Expansion of the PWN is apparent across four epochs—2000, 2006, 2009, and 2016. We find an expansion rate between 2000 and 2016 of the northwest edge of the PWN of 0.249% ± 0.023% yr‑1, for an expansion age R/(dR/dt) of 400 ± 40 yr and an expansion velocity of about 1000 km s‑1. We suggest that the PWN is expanding into an asymmetric nickel bubble in a conventional Type IIP supernova. Some acceleration of the PWN expansion is likely, giving a true age of 480 ± 50 yr. The pulsar’s birth luminosity was larger than the current value by a factor of 3–8, while the initial period was within a factor of 2 of its current value. We confirm directly that Kes 75 contains the youngest known PWN, and hence the youngest known pulsar. The pulsar PSR J1846‑0258 has a spindown-inferred magnetic field of 5 × 1013 G; in 2006, it emitted five magnetar-like short X-ray bursts, but its spindown luminosity has not changed significantly. However, the flux of the PWN has decreased by about 10% between 2009 and 2016, almost entirely in the northern half. A bright knot has declined by 30% since 2006. During this time, the photon indices of the power-law models did not change. This flux change is too rapid to be due to normal PWN evolution in one-zone models.

Simulation program for multiple expansion Stirling machines

International Nuclear Information System (INIS)

Walker, G.; Weiss, M.; Fauvel, R.; Reader, G.; Bingham, E.R.

1992-01-01

Multiple expansion Stirling machines have been a topic of interest at the University of Calgary for some years. Recently a second-order computer simulation program with integral graphics package for Stirling cryocoolers with up to four stages of expansion were developed and made available to the Stirling community. Adaptation of the program to multiple expansion Stirling power systems is anticipated. This paper briefly introduces the program and presents a specimen result

Hypoxia-Inducible Factors: Mediators of Cancer Progression; Prognostic and Therapeutic Targets in Soft Tissue Sarcomas

International Nuclear Information System (INIS)

Sadri, Navid; Zhang, Paul J.

2013-01-01

Soft-tissue sarcomas remain aggressive tumors that result in death in greater than a third of patients due to either loco-regional recurrence or distant metastasis. Surgical resection remains the main choice of treatment for soft tissue sarcomas with pre- and/or post-operational radiation and neoadjuvant chemotherapy employed in more advanced stage disease. However, in recent decades, there has been little progress in the average five-year survival for the majority of patients with high-grade soft tissue sarcomas, highlighting the need for improved targeted therapeutic agents. Clinical and preclinical studies demonstrate that tumor hypoxia and up-regulation of hypoxia-inducible factors (HIFs) is associated with decreased survival, increased metastasis, and resistance to therapy in soft tissue sarcomas. HIF-mediated gene expression regulates many critical aspects of tumor biology, including cell survival, metabolic programming, angiogenesis, metastasis, and therapy resistance. In this review, we discuss HIFs and HIF-mediated genes as potential prognostic markers and therapeutic targets in sarcomas. Many pharmacological agents targeting hypoxia-related pathways are in development that may hold therapeutic potential for treating both primary and metastatic sarcomas that demonstrate increased HIF expression

Mid-Miocene C4 expansion on the Chinese Loess Plateau under an enhanced Asian summer monsoon

Science.gov (United States)

Dong, Jibao; Liu, Zhonghui; An, Zhisheng; Liu, Weiguo; Zhou, Weijian; Qiang, Xiaoke; Lu, Fengyan

2018-06-01

Atmospheric CO2 starvation, aridity, fire and warm season precipitation have all been proposed as major contributors to C4 plant expansion during the Late Miocene. However, the driving factors responsible for the distribution of C4 plants in the early and mid-Miocene still remain enigmatic. Here we report pedogenic carbon and oxygen isotope data (δ13Cpedo, δ18Opedo), along with magnetic susceptibility (MS) results, from the Zhuang Lang drilling core on the Chinese Loess Plateau (CLP). Elevated δ13Cpedo values (>-5‰) signal a prominent C4 expansion and substantially increased δ18Opedo and MS values indicate enhanced Asian summer monsoon (ASM) precipitation. Both of these conditions are observed during the Mid-Miocene Climatic Optimum (MMCO), 14.5-17 million years ago. The marked increase in C4 plants, associated with warm temperatures and increased precipitation, strongly suggests the control of an enhanced ASM on C4 expansion on the CLP during the MMCO. This finding contrasts with the late-Miocene C4 expansion associated with cooling and drying conditions observed in low latitudes and argues for regionally specific control of C4 plant distribution/expansion.

Controlling Thermal Expansion: A Metal-Organic Frameworks Route.

Science.gov (United States)

Balestra, Salvador R G; Bueno-Perez, Rocio; Hamad, Said; Dubbeldam, David; Ruiz-Salvador, A Rabdel; Calero, Sofia

2016-11-22

Controlling thermal expansion is an important, not yet resolved, and challenging problem in materials research. A conceptual design is introduced here, for the first time, for the use of metal-organic frameworks (MOFs) as platforms for controlling thermal expansion devices that can operate in the negative, zero, and positive expansion regimes. A detailed computer simulation study, based on molecular dynamics, is presented to support the targeted application. MOF-5 has been selected as model material, along with three molecules of similar size and known differences in terms of the nature of host-guest interactions. It has been shown that adsorbate molecules can control, in a colligative way, the thermal expansion of the solid, so that changing the adsorbate molecules induces the solid to display positive, zero, or negative thermal expansion. We analyze in depth the distortion mechanisms, beyond the ligand metal junction, to cover the ligand distortions, and the energetic and entropic effect on the thermo-structural behavior. We provide an unprecedented atomistic insight on the effect of adsorbates on the thermal expansion of MOFs as a basic tool toward controlling the thermal expansion.

Controlling Thermal Expansion: A Metal–Organic Frameworks Route

Science.gov (United States)

2016-01-01

Controlling thermal expansion is an important, not yet resolved, and challenging problem in materials research. A conceptual design is introduced here, for the first time, for the use of metal–organic frameworks (MOFs) as platforms for controlling thermal expansion devices that can operate in the negative, zero, and positive expansion regimes. A detailed computer simulation study, based on molecular dynamics, is presented to support the targeted application. MOF-5 has been selected as model material, along with three molecules of similar size and known differences in terms of the nature of host–guest interactions. It has been shown that adsorbate molecules can control, in a colligative way, the thermal expansion of the solid, so that changing the adsorbate molecules induces the solid to display positive, zero, or negative thermal expansion. We analyze in depth the distortion mechanisms, beyond the ligand metal junction, to cover the ligand distortions, and the energetic and entropic effect on the thermo-structural behavior. We provide an unprecedented atomistic insight on the effect of adsorbates on the thermal expansion of MOFs as a basic tool toward controlling the thermal expansion. PMID:28190918

Platform Expansion Design as Strategic Choice

DEFF Research Database (Denmark)

Staykova, Kalina S.; Damsgaard, Jan