Revealing internal flow behaviour in arc welding and additive manufacturing of metals

Internal flow behaviour during melt-pool-based metal manufacturing remains unclear and hinders progression to process optimisation. In this contribution, we present direct time-resolved imaging of melt pool flow dynamics from a high-energy synchrotron radiation experiment. We track internal flow streams during arc welding of steel and measure instantaneous flow velocities ranging from 0.1 m s−1 to 0.5 m s−1. When the temperature-dependent surface tension coefficient is negative, bulk turbulence is the main flow mechanism and the critical velocity for surface turbulence is below the limits identified in previous theoretical studies. When the alloy exhibits a positive temperature-dependent surface tension coefficient, surface turbulence occurs and derisory oxides can be entrapped within the subsequent solid as result of higher flow velocities. The widely used arc welding and the emerging arc additive manufacturing routes can be optimised by controlling internal melt flow through adjusting surface active elements

Placental transfer of the polybrominated diphenyl ethers BDE-47, BDE-99 and BDE-209 in a human placenta perfusion system: an experimental study

<p>Abstract</p> <p>Background</p> <p>Polybrominated diphenyl ethers (PBDEs) have been widely used as flame retardants in consumer products. PBDEs may affect thyroid hormone homeostasis, which can result in irreversible damage of cognitive performance, motor skills and altered behaviour. Thus, in utero exposure is of very high concern due to critical windows in fetal development.</p> <p>Methods</p> <p>A human ex vivo placenta perfusion system was used to study the kinetics and extent of the placental transfer of BDE-47, BDE-99 and BDE-209 during four-hour perfusions. The PBDEs were added to the maternal circulation and monitored in the maternal and fetal compartments. In addition, the perfused cotyledon, the surrounding placental tissue as well as pre-perfusion placental tissue and umbilical cord plasma were also analysed. The PBDE analysis included Soxhlet extraction, clean-up by adsorption chromatography and GC-MS analysis.</p> <p>Results and Discussion</p> <p>Placental transfer of BDE-47 was faster and more extensive than for BDE-99. The fetal-maternal ratios (FM-ratio) after four hours of perfusion were 0.47 and 0.25 for BDE-47 and BDE-99, respectively, while the indicative permeability coefficient (IPC) measured after 60 minutes of perfusion was 0.26 h^-1and 0.10 h^-1, respectively. The transport of BDE-209 seemed to be limited. These differences between the congeners may be related to the degree of bromination. Significant accumulation was observed for all congeners in the perfused cotyledon as well as in the surrounding placental tissue.</p> <p>Conclusion</p> <p>The transport of BDE-47 and BDE-99 indicates in utero exposure to these congeners. Although the transport of BDE-209 was limited, however, possible metabolic debromination may lead to products which are both more toxic and transportable. Our study demonstrates fetal exposure to PBDEs, which should be included in risk assessment of PBDE exposure of women of child-bearing age.</p

Figuring Rhetoric: From Antistrophe to Apostrophe through Catastrophe

This essay explores rhetoric tropologically through various strophes: antistrophe, catastrophe, and apostrophe. Our purpose is to delineate problems and possibilities that these tropes pose for rhetoric in an effort to create new rhetorics. We seek to display the antistrophic and catastrophic figurations of rhetoric and then use visual lenses of photography and cinema to disrupt the figurations. Following the disruption, we seek to heighten sensibilities to other figurations, in particular an apostrophic figuration. We cast apostrophe as a figure for change because it marks a deeply felt turn toward difference and otherness. Turned as such, rhetoric becomes erotic

Meta-analysis of genome-wide association studies from the CHARGE consortium identifies common variants associated with carotid intima media thickness and plaque

Carotid intima media thickness (cIMT) and plaque determined by ultrasonography are established measures of subclinical atherosclerosis that each predicts future cardiovascular disease events. We conducted a meta-analysis of genome-wide association data in 31,211 participants of European ancestry from nine large studies in the setting of the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Consortium. We then sought additional evidence to support our findings among 11,273 individuals using data from seven additional studies. In the combined meta-analysis, we identified three genomic regions associated with common carotid intima media thickness and two different regions associated with the presence of carotid plaque (P < 5 × 10 -8). The associated SNPs mapped in or near genes related to cellular signaling, lipid metabolism and blood pressure homeostasis, and two of the regions were associated with coronary artery disease (P < 0.006) in the Coronary Artery Disease Genome-Wide Replication and Meta-Analysis (CARDIoGRAM) consortium. Our findings may provide new insight into pathways leading to subclinical atherosclerosis and subsequent cardiovascular events

The supportive care needs of parents with a child with a rare disease : results of an online survey

Background: Parents caring for a child affected by a rare disease have unmet needs, the origins of which are complex and varied. Our aim was to determine the supportive care needs of parents caring for a child with a rare disease. Methods: An online survey was developed consisting of 45 questions (108 items) and separated into six domains. The survey included questions about perceived level of satisfaction with receiving care, experiences and needs of providing daily care, the impacts of disease on relationships, the emotional and psychological burdens of disease, and parents overall satisfaction with the support received. Results: Three-hundred and one parents from Australia and New Zealand completed the survey; 91 % (n = 275/301) were mothers, with 132 distinct rare diseases being reported. Fifty-four percent (n = 140/259) of parents were dissatisfied with health professionals’ level of knowledge and awareness of disease; 71 % (n = 130/183) of parents felt they received less support compared to other parents. Information regarding present (60 %, n = 146/240) and future services (72 %, n = 174/240) available for their child were considered important. Almost half of parents (45 %, n = 106/236) struggled financially, 38 % (n = 99/236) reduced their working hours and 34 % (n = 79/236) ceased paid employment. Forty-two percent (n = 99/223) of parents had no access to a disease specific support group, and 58 % (n = 134/230) stated that their number of friends had reduced since the birth of their child; 75 % (n = 173/230) had no contact with other parents with a child with a similar disease, and 46 % (n = 106/230) reported feeling socially isolated and desperately lonely. Most frequent emotions expressed by parents in the week prior to completing the survey were anxiety and fear (53 %, n = 119/223), anger and frustration (46 %, n = 103/223) and uncertainty (39 %, n = 88/223). Conclusion: This study is the first to develop an online survey specifically for use with parents to investigate their supportive care needs across a large and diverse group of rare diseases. The findings highlight that parents with a child with a rare disease have common unmet needs regardless of what disease their child has. Such information may allow health providers to improve child outcomes through improving parental supportive care

Computation of Equilibria in OLG Models with Many Heterogeneous Households

This paper develops a decomposition algorithm by which a market economy with many households may be solved through the computation of equilibria for a sequence of representative agent economies. The paper examines local and global convergence properties of the sequential recalibration (SR) algorithm. The SR algorithm is then demonstrated to efficiently solve Auerbach–Kotlikoff OLG models with a large number of heterogeneous households. We approximate equilibria in OLG models by solving a sequence of related Ramsey optimal growth problems. This approach can provide improvements in both efficiency and robustness as compared with integrated complementarity-based solution methods.Alfried Krupp von Bohlen und Halbach Foundatio

DNA Encoding an HIV-1 Gag/Human Lysosome-Associated Membrane Protein-1 Chimera Elicits a Broad Cellular and Humoral Immune Response in Rhesus Macaques

Previous studies of HIV-1 p55Gag immunization of mice have demonstrated the usefulness of targeting antigens to the cellular compartment containing the major histocompatibility complex type II (MHC II) complex molecules by use of a DNA antigen formulation encoding Gag as a chimera with the mouse lysosome-associated membrane protein (mLAMP/gag). In the present study, we have analyzed the magnitude and breadth of Gag-specific T-lymphocyte and antibody responses elicited in Rhesus macaques after immunization with DNA encoding a human LAMP/gag (hLAMP/gag) chimera. ELISPOT analyses indicated that the average Gag-specific IFN-γ response elicited by the hLAMP/gag chimera was detectable after only two or three naked DNA immunizations in all five immunized macaques and reached an average of 1000 spot-forming cells (SFC)/10(6) PBMCs. High IFN-γ ELISPOT responses were detected in CD8(+)-depleted cells, indicating that CD4(+) T-cells play a major role in these responses. The T-cell responses of four of the macaques were also tested by use of ELISPOT to 12 overlapping 15-amino acids (aa) peptide pools containing ten peptides each, encompassing the complete Gag protein sequence. The two Mamu 08 immunized macaques responded to eight and twelve of the pools, the Mamu B01 to six, and the other macaque to five pools indicating that the hLAMP/gag DNA antigen formulation elicits a broad T-cell response against Gag. Additionally, there was a strong HIV-1-specific IgG response. The IgG antibody titers increased after each DNA injection, indicating a strong amnestic B-cell response, and were highly elevated in all the macaques after three immunizations. Moreover, the serum of each macaque recognized 13 of the 49 peptides of a 20-aa peptide library covering the complete Gag amino acid sequence. In addition, HIV-1-specific IgA antibodies were present in the plasma and external secretions, including nasal washes. These data support the findings of increased immunogenicity of genetic vaccines encoded as LAMP chimeras, including the response to DNA vaccines by non-human primates