bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of fatigue crack growth rate of selective laser sintered RapidSteel via computational fracture mechanics
Authors: Okyar Ali Fethi , Uzunsoy Deniz , Ozsoy Burak 
Published: April 2014

AbstractThe fatigue-crack growth behavior of materials manufactured by means of selective laser sintering was studied. In the process, specimens were prepared from metal powders (316 steel) into the desired shape by additive manufacturing technology, followed by sintering and infiltration in a suitable molten metal. The latter process was aimed at eliminating the inherent porosity associated with powder metallurgy. Porosity is known to adversely affect the fatigue-crack growth rate behavior of powder metallurgy components. Carefully conducted fatigue-crack growth rate tests (single-edge-notch four-point bending type) were carried out on RapidSteelTMand the results were compared with data of infiltrated low carbon steel in the literature. Finite element analysis was carried out as an intermediate step in order to validate the geometry factor calculations provided by empirical formulae. It was found that the fracture resistance of RapidSteel was higher compared with low-carbon copper infiltrated steel tempered at 177 °C and 428 °C, and same as that tempered at 704 °C.
Influence of hot working on mechanical and physical properties of an Fe – Ni – Co alloy
Authors: Abbasi Seyed Mehdi , Momeni Amir , Morakkabati Maryam , Mahdavi Rashid 
Published: April 2014

Abstract
The flow behavior, mechanical and physical properties of alloy Fe-29 Ni-17 Co were studied using hot compression and hot rolling tests over the temperature range of 900 °C to1 200 °C and strain rates of 0.001 s−1 to 1 s−1. At temperatures below 1 100 °C, the flow curves were similar to those of dynamic recovery; whereas, at higher temperatures, faint peaks appeared on the flow curves. A modified power-law constitutive equation was used to model the dependences of flow stress on temperature and strain rate in different deformation regimes. The Kocks–Mecking equation was used to model the flow curves and to measure the mean flow stress of the material in hot rolling. The samples hot rolled at 1 100 – 1 200 °C to a reduction of 30 – 40 % showed the best combination of ductility and strength and low thermal expansion coefficient. Microstructures of the hot rolled samples indicated that hot rolling at 1 100 – 1 200 °C to reduction of 30 – 40 % leads to complete dynamic recrystallization.
Seed damage and sources of yield loss by Sitodiplosis mosellana (Diptera: Cecidomyiidae) in resistant wheat varietal blends relative to susceptible wheat cultivars in western Canada
Authors: Smith M.A.H. , Wise I.L. , Fox S.L. , Vera C.L. , DePauw R.M. , Lukow O.M. 
Published: April 2014

AbstractSpring wheat varieties with the Sm1 gene for resistance to wheat midge, Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae), were compared with susceptible wheat (Triticum Linnaeus; Poaceae) with respect to sources of yield loss and reduction in market value from wheat midge feeding damage. Four resistant varietal blends (90% Sm1 wheat plus 10% susceptible refuge) and four susceptible cultivars were grown in replicated experiments at eight locations in western Canada. Frequencies and 1000-kernel weights of undamaged and midge-damaged seeds were assessed before harvest by dissecting samples of ripe spikes, and after harvest in samples of cleaned grain. Spike data were used to estimate yield losses from reduced weight of damaged seeds and loss of severely damaged seeds (⩽8 mg) at harvest. Among midge-damaged seeds in spikes, few were severely damaged in resistant varietal blends, whereas most were severely damaged in susceptible cultivars. Cleaned, harvested grain of resistant varietal blends and susceptible cultivars had similar frequencies of midge damage and were assessed similar market grades. The primary benefit of midge-resistant wheat was reduced yield loss due to seed damage by wheat midge larvae. Resistant wheat did not protect against loss of market grade, but market value could increase due to larger yields.
Consumption of flea beetles (Phyllotreta, Coleoptera: Chrysomelidae) by spiders in field habitats detected by molecular analysis
Authors: Ekbom Barbara , Kuusk Anna-Karin , Malsher Gerard , Åström Sandra , Cassel-Lundhagen Anna 
Published: April 2014

AbstractFlea beetles, Phyllotreta Chevrolat (Coleoptera: Chrysomelidae) species, are often found in oilseed rape (OSR), Brassica napus Linnaeus (Brassicaceae). Among predators in the generalist predator complex present in agricultural fields, wolf spiders (Araneae: Lycosidae) are found on the ground and cobweb spiders (Araneae: Theridiidae) build webs in the foliage. We present group-specific primers developed for five flea beetle species within the genus Phyllotreta and study the incidence of predation of flea beetles by these spider groups using DNA-based gut-content analysis. Wolf spiders of the genus Pardosa Koch and the cobweb spider, Phylloneta impressa (Koch), were collected in three winter OSR fields. Flea beetle densities as well as the occurrence of predators and alternative prey were monitored. In total 19.4% of the collected Pardosa tested positive for flea beetle DNA in the polymerase chain reaction analyses, whereas 10% P. impressa were positive. Pardosa were more likely to be positive for flea beetle DNA when Pardosa activity density was low. Phylloneta impressa were more likely to be positive for flea beetle DNA if they were positive for pollen beetle DNA. Implications of these results for conservation biological control and future studies of food webs in OSR are discussed.
Validation of a methodology for rearingSpalangia cameroni(Hymenoptera: Pteromalidae) onCeratitis capitata(Diptera: Tephritidae)
Authors: Tormos J. , Sabater-Muñoz B. , Asís J.D. , Beitia F. 
Published: April 2014

AbstractSpalangia cameroniPerkins (Hymenoptera: Pteromalidae) is a pupal parasitoid of the Medfly,Ceratitis capitata(Wiedmann) (Diptera: Tephritidae), one of the principal pests of Spanish agriculture.Spalangia cameroniis a potential biocontrol agent for this pest if methods can be developed to mass-rear it effectively onC. capitata. Here, we report on the use of freeze-killed pupae ofC. capitatato maintain a laboratory colony ofS. cameroni, with a view to setting up a mass-rearing protocol. Realised fecundity, adult progeny, sex ratio, and superparasitism level were the principal parameters analysed. No significant differences were found in respect of these parameters between living or freeze-killed Medfly pupae used as hosts, although sex ratios showed a bias towards females in the case of freeze-killed pupae. Freeze-killed pupae were concluded to present the best option for the laboratory-rearing ofS. cameroni, on account of ease of rearing, and avoidance of the emergence of Medfly adults.
First Nearctic record ofDiolcogaster claritibia(Hymenoptera: Braconidae: Microgastrinae), with notes on taxonomic status and natural history
Authors: Fernandez-Triana Jose , Shaw Mark R. , Cardinal Sophie , Dosdall Lloyd , Mason Peter 
Published: April 2014

AbstractThe Microgastrinae waspDiolcogaster claritibia(Papp, 1959) (Hymenoptera: Braconidae), a parasitoid of the diamondback moth,Plutella xylostella(Linnaeus, 1758) (Lepidoptera: Plutellidae), is recorded from the Nearctic region (Alberta, Manitoba, and Ontario, Canada) for the first time. In spite of some minor morphological and molecular (DNA barcoding) differences, the available data indicate that the European and New World specimens should be considered one species, but more specimens and loci need to be sampled to conclusively determine the phylogeographic history of the species.Diolcogaster claritibiaseems to be widely distributed within the Holarctic, and the molecular data suggest that it was recently introduced to North America from Europe.
Therapeutic Effect of IVIG on Inflammatory Arthritis in Mice Is Dependent on the Fc Portion and Independent of Sialylation or Basophils
Authors: Campbell Ian K. , Miescher Sylvia , Branch Donald R. , Mott Patrick J. , Lazarus Alan H. , Han Dongji , Maraskovsky Eugene , Zuercher Adrian W. , Neschadim Anton , Leontyev Danila , McKenzie Brent S. , Käsermann Fabian 
Published: April 2014

Abstract
High-dose i.v. Ig (IVIG) is used to treat various autoimmune and inflammatory diseases; however, the mechanism of action remains unclear. Based on the K/BxN serum transfer arthritis model in mice, IVIG suppression of inflammation has been attributed to a mechanism involving basophils and the binding of highly sialylated IgG Fc to DC-SIGN–expressing myeloid cells. The requirement for sialylation was examined in the collagen Ab-induced arthritis (CAbIA) and K/BxN serum transfer arthritis models in mice. High-dose IVIG (1–2 g/kg body weight) suppressed inflammatory arthritis when given prophylactically. The same doses were also effective in the CAbIA model when given subsequent to disease induction. In this therapeutic CAbIA model, the anti-inflammatory effect of IVIG was dependent on IgG Fc but not F(ab′)2 fragments. Removal of sialic acid residues by neuraminidase had no impact on the anti-inflammatory activity of IVIG or Fc fragments. Treatment of mice with basophil-depleting mAbs did not abrogate the suppression of either CAbIA or K/BxN arthritis by IVIG. Our data confirm the therapeutic benefit of IVIG and IgG Fc in Ab-induced arthritis but fail to support the significance of sialylation and basophil involvement in the mechanism of action of IVIG therapy.
Kinetics of B Cell Responses to Plasmodium falciparum Erythrocyte Membrane Protein 1 in Ghanaian Women Naturally Exposed to Malaria Parasites
Authors: Ampomah Paulina , Stevenson Liz , Ofori Michael F. , Barfod Lea , Hviid Lars 
Published: April 2014

Abstract
Naturally acquired protective immunity to Plasmodium falciparum malaria takes years to develop. It relies mainly on Abs, particularly IgG specific for Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) proteins on the infected erythrocyte surface. It is only partially understood why acquisition of clinical protection takes years to develop, but it probably involves a range of immune-evasive parasite features, not least of which are PfEMP1 polymorphism and clonal variation. Parasite-induced subversion of immunological memory and expansion of “atypical” memory B cells may also contribute. In this first, to our knowledge, longitudinal study of its kind, we measured B cell subset composition, as well as PfEMP1-specific Ab levels and memory B cell frequencies, in Ghanaian women followed from early pregnancy up to 1 y after delivery. Cell phenotypes and Ag-specific B cell function were assessed three times during and after pregnancy. Levels of IgG specific for pregnancy-restricted, VAR2CSA-type PfEMP1 increased markedly during pregnancy and declined after delivery, whereas IgG levels specific for two PfEMP1 proteins not restricted to pregnancy did not. Changes in VAR2CSA-specific memory B cell frequencies showed typical primary memory induction among primigravidae and recall expansion among multigravidae, followed by contraction postpartum in all. No systematic changes in the frequencies of memory B cells specific for the two other PfEMP1 proteins were identified. The B cell subset analysis confirmed earlier reports of high atypical memory B cell frequencies among residents of P. falciparum–endemic areas, and indicated an additional effect of pregnancy. Our study provides new knowledge regarding immunity to P. falciparum malaria and underpins efforts to develop PfEMP1-based vaccines against this disease.
Heat Shock Proteins as Endogenous Adjuvants in Sterile and Septic Inflammation
Authors: Quintana Francisco J. , Cohen Irun R. 
Published: April 2014

Abstract
Heat shock proteins (HSPs) have been reported to stimulate the immune system via innate receptors. However, the role of HSPs as endogenous adjuvants has been challenged by reports claiming that pure HSPs are not innate ligands; it is only the bacterial molecules trapped by the HSPs that can signal the innate immune system. In this review, we discuss data suggesting that both views, in essence, are correct; pure HSPs are indeed innate immunostimulators, but HSPs can also function as transducers of pathogen signals. In other words, HSPs perform diverse functions in two alternative modes of inflammation: sterile inflammation, which results from endogenous stimuli and is necessary for body maintenance, and septic inflammation, which protects us from environmental pathogens. Endogenous HSPs are key players in the modulation of these two modes of inflammation, and as such, they are potential targets for new and more efficient therapies for cancer, infections, and autoimmunity.
Follicular Dendritic Cells Catalyze Hepatocyte Growth Factor (HGF) Activation in the Germinal Center Microenvironment by Secreting the Serine Protease HGF Activator
Authors: Tjin Esther P. M. , Bende Richard J. , Derksen Patrick W. B. , van Huijstee Anne-Pauline , Kataoka Hiroaki , Spaargaren Marcel , Pals Steven T. 
Published: April 2014

Abstract
Ag-specific B cell differentiation, the process that gives rise to plasma cells and memory B cells, involves the formation of germinal centers (GC). Within the GC microenvironment, multiple steps of B cell proliferation, selection, and maturation take place, which are controlled by the BCR in concert with cytokines and contact-dependent signals from follicular dendritic cells (FDCs) and T cells. Signaling by the multifunctional cytokine hepatocyte growth factor (HGF) and its receptor MET has been shown to induce integrin-mediated adhesion of B cells to VCAM-1, which is expressed by FDCs. In the present study we have examined the expression of regulatory components of the HGF/MET pathway, including HGF activator (HGFA), within the secondary lymphoid organ microenvironment. We show that MET is expressed by both centroblasts and plasma cells, and that HGFA is expressed by plasma cells. Because we have shown that HGF is a potent growth and survival factor for malignant plasma cells, HGF may also serve as a survival factor for normal plasma cells. Furthermore, we demonstrate that FDCs are the major source for HGF and its activator within the GC microenvironment. Both HGF and HGFA are expressed by FDCs in the GC dark zone (CD21high/CD23low), but not in the light zone (CD21high/CD23high). These findings suggest that HGF and HGFA provided by dark zone FDCs help to regulate the proliferation, survival, and/or adhesion of MET-positive centroblasts.
Gi-Protein-Dependent Inhibition of IL-12 Production Is Mediated by Activation of the Phosphatidylinositol 3-Kinase-Protein 3 Kinase B/Akt Pathway and JNK
Authors: la Sala Andrea , Gadina Massimo , Kelsall Brian L. 
Published: April 2014

Abstract
Ligands for certain Gi-protein-coupled receptors (GiPCRs) potently inhibit the production of IL-12 by human monocytes. We addressed the intracellular signaling mechanisms by which this occurs using primary human cells. Stimulation with the GiPCR ligands C5a and 1-deoxy-1-[6-[(3-iodophenyl)methyl]amino]-9H-purine-9-y1]-N-methyl-β-d-ribofuranuronamide (IB-MECA) blocked the production of IL-12 p70 by human monocytes stimulated with LPS and IFN-γ. In addition, C5a reduced the expression of mRNA for IL-12 p35, p40, IL-23 p19, and IL-27 p28. This effect was due neither to a down-regulation of TLR4 or IFN-γ receptor on the cell surface nor to interference with IFN-γ signaling, because IFN-γ-induced up-regulation of HLA-DR and CD40 were unaffected. C5a or IB-MECA activated the PI3K/Akt signaling pathway and induced the phosphorylation of the MAPK p38, ERK, and JNK. Inhibition of the PI3K/Akt signaling pathway with wortmannin or an inhibitor of Akt activity, and inhibition of JNK but not ERK prevented IL-12 and IL-23 suppression by C5a. These data extend observations on IL-12 suppression by C5a to IL-23 and IL-27, and are the first to demonstrate the intracellular signaling events leading to IL-12 and IL-23 inhibition after GiPCR activation.
In Vivo Generation of Pathogen-Specific Th1 Cells in the Absence of the IFN-γ Receptor
Authors: Haring Jodie S. , Badovinac Vladimir P. , Olson Matthew R. , Varga Steven M. , Harty John T. 
Published: April 2014

Abstract
The precise mechanisms that govern the commitment of CD4 T cells to become Th1 or Th2 cells in vivo are incompletely understood. Recent experiments demonstrate colocalization of the IFN-γR chains with the TCR during activation of naive CD4 T cells, suggesting that association of these molecules may be involved in determining lineage commitment. To test the role of IFN-γ and its receptor in the generation of Th1 Ag-specific CD4 T cells, we analyzed mice after infection with Listeria monocytogenes or lymphocytic choriomeningitis virus. In the absence of IFN-γ, Ag-specific CD4 T cells were generated in response to both these infections. In addition, IFN-γ-producing (Th1) Ag-specific CD4 T cells were generated in mice lacking the ligand-binding chain of the IFN-γR (IFN-γR1−/−) or the signaling chain (IFN-γR2−/−). There was no increase in the number of IL-4-producing Ag-specific CD4 T cells, nor was there a decrease in the expression of T-bet in the absence of functional IFN-γ signaling, indicating that the cells were committed Th1 cells. Thus, both chains of the IFN-γR are dispensable for the generation of Th1 Ag-specific CD4 T cells after infection in vivo.
Intraepithelial NK Cell-Derived IL-13 Induces Intestinal Pathology Associated with Nematode Infection
Authors: McDermott Jacqueline R. , Humphreys Neil E. , Forman Simon P. , Donaldson Debra D. , Grencis Richard K. 
Published: April 2014

Abstract
IL-13 is a Th2-derived cytokine associated with pathological changes in asthma and ulcerative colitis. Moreover, it plays a major role in the control of gut nematode infection and associated immunopathology. The current paradigm is that these effects are due to T cell-derived IL-13. We show in this study that an innate source of IL-13, the intraepithelial NK cell, is responsible for the disruption of intestinal tissue architecture and induction of goblet cell hyperplasia that characterizes infection with the intestinal helminth Trichinella spiralis. IL-13 or IL-4Rα (but not IL-4) null mice failed to induce intestinal pathology. Unexpectedly, SCID and athymic mice developed the same pathology found in immunocompetent mice following infection. Moreover, immunodeficient mice expressed IL-13 in the intestine, and abnormal mucosal pathology was reduced by in vivo administration of a soluble IL-13 antagonist. IL-13 expression was induced in non-T intraepithelial CD3− NK cells. Epithelial cells expressed the IL-13 signaling receptor, IL-13Rα1, and after infection, IL-4Rα. Furthermore, the soluble IL-13 decoy receptor IL-13Rα2, which regulates IL-13 responses, was also induced upon infection. These data provide the first evidence that intestinal tissue restructuring during helminth infection is an innate event dependent on IL-13 production by NK cells resident in the epithelium of the intestine.
Functional Analysis of Granzyme M and Its Role in Immunity to Infection
Authors: Pao Lily I. , Sumaria Nital , Kelly Janice M. , Dommelen Serani van , Cretney Erika , Wallace Morgan E. , Anthony Desiree A. , Uldrich Adam P. , Godfrey Dale I. , Papadimitriou John M. , Mullbacher Arno , Degli-Esposti Mariapia A. , Smyth Mark J. 
Published: April 2014

AbstractCytotoxic lymphocytes express a large family of granule serine proteases, including one member, granzyme (Grz)M, with a unique protease activity, restricted expression, and distinct gene locus. Although a number of Grzs, including GrzM, have been shown to mediate target cell apoptosis in the presence of perforin, the biological activity of Grz has been restricted to control of a number of viral pathogens, including two natural mouse pathogens, ectromelia, and murine CMV (MCMV). In this article, we describe the first reported gene targeting of GrzM in mice. GrzM-deficient mice display normal NK cell/T cell development and homeostasis and intact NK cell-mediated cytotoxicity of tumor targets as measured by membrane damage and DNA fragmentation. GrzM-deficient mice demonstrated increased susceptibility to MCMV infection typified by the presence of more viral inclusions and transiently higher viral burden in the visceral organs of GrzM-deficient mice compared with wild-type (WT) mice. The cytotoxicity of NK cells from MCMV-infected GrzM-deficient mice remained unchanged and, like WT control mice, GrzM-deficient mice eventually effectively cleared MCMV infection from the visceral organs. In contrast, GrzM-deficient mice were as resistant as WT control mice to mouse pox ectromelia infection, as well as challenge with a number of NK cell-sensitive tumors. These data confirm a role for GrzM in the host response to MCMV infection, but suggest that GrzM is not critical for NK cell-mediated cytotoxicity.
An Innate Immune System Cell Is a Major Determinant of Species-Related Susceptibility Differences to Fungal Pneumonia
Authors: Shao Xiuping , Mednick Aron , Alvarez Mauricio , van Rooijen Nico , Casadevall Arturo , Goldman David L. 
Published: April 2014

Abstract
Rats and mice are considered resistant and susceptible hosts, respectively, for experimental cryptococcosis. For both species, alveolar macrophages (AM) are central components of the host response to pulmonary Cryptococcus neoformans infection. We explored the role of AM in three strains of mice and three strains of rats during cryptococcal infection by comparing the outcome of infection after macrophage depletion using liposomal clodronate. AM depletion was associated with enhancement and amelioration of disease in rats and mice, respectively, as measured by lung fungal burden. The apparent protective role for AM in rats correlated with enhanced anticryptococcal activity as measured by phagocytic activity, oxidative burst, lysozyme secretion, and ability to limit intracellular growth of C. neoformans. Furthermore, rat AM were more resistant to lysis in association with intracellular infection. In summary, differences in AM function in rats and mice suggest an explanation for the species differences in susceptibility to C. neoformans based on the inherent efficacy of a central effector cell of the innate immune system.
Complement Regulator-Acquiring Surface Protein 1 Imparts Resistance to Human Serum in Borrelia burgdorferi
Authors: Brooks Chad S. , Vuppala Santosh R. , Jett Amy M. , Alitalo Antti , Meri Seppo , Akins Darrin R. 
Published: April 2014

Abstract
Factor H and factor H-like protein 1 (FH/FHL-1) are soluble serum proteins that negatively regulate the alternative pathway of complement. It is now well recognized that many pathogenic bacteria, including Borrelia burgdorferi, bind FH/FHL-1 on their cell surface to evade complement-mediated destruction during infection. Recently, it was suggested that B. burgdorferi open reading frame bbA68, known as complement regulator-acquiring surface protein 1 (CRASP-1), encodes the major FH/FHL-1-binding protein of B. burgdorferi. However, because several other proteins have been identified on the surface of B. burgdorferi that also can bind FH/FHL-1, it is presently unclear what role CRASP-1 plays in serum resistance. To examine the contribution of CRASP-1 in serum resistance, we generated a B. burgdorferi mutant that does not express CRASP-1. The B. burgdorferi CRASP-1 mutant, designated B31cF-CRASP-1, was found to be as susceptible to human serum as a wild-type strain of Borrelia garinii 50 known to be sensitive to human serum. To further examine the role of CRASP-1 in serum resistance, we also created a shuttle vector that expresses CRASP-1 from the native B. burgdorferi gene, which was designated pKFSS-1::CRASP-1. When the pKFSS-1::CRASP-1 construct was transformed into the B. burgdorferi B31cF-CRASP-1 mutant, wild-type levels of serum resistance were restored. Additionally, when pKFSS-1::CRASP-1 was transformed into the serum-sensitive B. garinii 50 isolate, human serum resistance was imparted on this strain to a level indistinguishable from wild-type B. burgdorferi. The combined data led us to conclude that CRASP-1 expression is necessary for B. burgdorferi to resist killing by human serum.