On the Existence of an Optimum End-to-side Junctional Geometry in Peripheral Bypass Surgery—A Computer Generated Study

AbstractBackground. To investigate hemodynamic flow changes associated with vein cuffs and patches that may be responsible for improved patency of prosthetic infrainguinal grafts.Methods. The role of the graft–artery junction angle was examined by computational fluid dynamics to assess the influence of anastomotic geometry on wall shear stress (WSS) distributions. Three geometrically different junction configurations were studied and the WSS and WSS gradient (WSSG) values were compared.Results. The inclusion of a patch or a cuff moves the bed stagnation point (BSP) distally, increasing the area on the bed of the junction which experiences a BSP and reducing the strength of the recirculation region opposite the heel of the junction by 54.8 and 50.8%, respectively. The patched geometry promotes earlier recovery of the flow in the distal outflow segment (DOS) than for the unpatched model. Also, the helical flow patterns in the DOS associated with the cuffed geometry are stronger. The net effect of these changes are that peak WSSG values for the patched and cuffed geometries are three times lower than those for the uncuffed geometry.Conclusion. This study provides some additional insights into the hemodynamics of graft–artery junction geometry which may influence future clinical practice

The colonised self: the politics of UK asylum practices, and the embodiment of colonial power in lived experience

This paper draws on empirical data generated in the ‘Everyday Bordering in the UK’ project, with a focus on the experiences of people seeking asylum and hoping to establish a safe life in the UK. Specifically, we show that during the process of claiming asylum, people’s experiences of waiting and displacement—practices inherent in UK immigration policies—work as time- and space-based dimensions of power that are imbued with colonial logic. Existing studies apply the lens of Foucault’s governmentality approach to politics regulating people seeking asylum. In particular, the international literature describes the policy of dispersal, and associated periods of waiting, as a dynamic of power used by governments to control and regulate behaviours. However, these time- and space-related experiences are often considered separately, focusing on the rationalities underpinning these politics. This paper, by contrast, develops Foucault’s theories by examining how these two characteristics interconnect in the lived realities of people waiting for an asylum decision in the UK to create racialised politics of power and privilege that reproduce the colonial origins of European migration governance. In doing so, we contribute by illustrating how practices within the UK asylum system can be embodied by people seeking asylum to create a subject that modifies behaviours in response to being positioned as ‘less deserving’ than UK citizens—the ‘colonised self’

Absence Of Adamts13 On A Vwf Deficient Background Is No Longer Prothrombotic In A Murine Model Of Arterial Thrombosis

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106148/1/jth00411.pd

Dietary omega-3 polyunsaturated fatty acids prevent vascular dysfunction and attenuate cytochrome P4501A1 expression by 2,3,7,8-tetrachlorodibenzo-p-dioxin

Omega-3 polyunsaturated fatty acids (n-3 PUFAs) found in fish protect against cardiovascular morbidity and mortality; however, many individuals avoid fish consumption due to concerns about pollutants. We tested the hypothesis that n-3 PUFAs would prevent vascular dysfunction induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). C57Bl/6 male mice were fed a chow or n-3 PUFA diet for 10 weeks and were exposed to vehicle or 300 ng/kg/d TCDD during the final 2 weeks on each diet. Aortic vasoconstriction mediated by arachidonic acid (AA) +/- SKF525 (P450 inhibitor) or SQ29548 (thromboxane/prostanoid (TP) receptor antagonist) was assessed. RBC fatty acids and expression of n-3 and n-6 PUFA metabolites were analyzed. Cytochrome P4501A1 (CYP1A1), CYP1B1, and aryl hydrocarbon receptor (AHR) expression was measured. TCDD significantly increased AA-mediated vasoconstriction on a chow diet by increasing the contribution of P450s and TP receptor to the constriction response. In contrast, the n-3 PUFA diet prevented the TCDD-induced increase in AA vasoconstriction and normalized the contribution of P450s and TP receptor. While TCDD increased the levels of AA vasoconstrictors on the chow diet, this increase was prevent by the n-3 PUFA diet. Additionally, the n-3 PUFA diet significantly increased the levels of n-3 PUFA-derived vasodilators and TCDD increased these levels further. Interestingly, the n-3 PUFA diet significantly attenuated CYP1A1 induction by TCDD without a significant effect on AHR expression. These data suggest that n-3 PUFAs can prevent TCDD-induced vascular dysfunction by decreasing vasoconstrictors, increasing vasodilators, and attenuating CYP1A1 induction, which has been shown previously to contribute to TCDD-induced vascular dysfunction

Serum proteins in healthy and diseased Florida manatees (Trichechus manatus latirostris)

A major goal of this study was to determine whether serum protein fractions of healthy Florida manatees differ with age, sex, or living environments (wild versus housed). A second goal was to determine which serum protein fractions vary in diseased versus healthy manatees. Serum protein fractions were determined using agarose gel electrophoresis. Healthy adults had slightly higher total serum protein and total globulin concentrations than younger animals. This largely resulted from an increase in gamma globulins with age. Total serum protein, albumin, alpha-1 globulin, beta globulin, and total globulin concentrations were slightly higher in housed manatees compared to wild manatees, but there was no significant difference in the albumin/globulin (A/G) ratio, suggesting a difference in hydration between these groups. No significant differences were attributable to sex or pregnancy. Serum albumin concentrations and A/G ratios were significantly lower for manatees with boat trauma, entanglements, emaciation, or cold stress compared to healthy manatees. Variable increases were seen in alpha-1globulins, alpha-2 globulins, beta globulins, and gamma globulins. These globulin fractions contain positive acute-phase proteins and immunoglobulins, and their increases may reflect acute or chronic active inflammation. Changes in serum protein fractions were not consistent enough to justify the use of serum protein electrophoresis as a routine diagnostic test for manatees. However, serum (or plasma) protein electrophoresis is required when accurate values for albumin and globulins are needed in manatees and in determining which protein fractions may account for a hyperproteinemia or hypoproteinemia reported in a clinical chemistry panel

Portholes of ethnography: the methodological learning from 'being there' at a distance.

Ethnography is, in essence, an approach to social research reliant on ‘being there’ and ethnographic approaches to the social world have been widely taken up in sociological research. In this research note, we share our UK-based experiences of ethnographic fieldwork with professional practitioners during the initial months of the COVID-19 pandemic, when ‘staying at home’ was the antithesis of ‘being there’. In doing so, we highlight opportunities the pandemic presented to re-evaluate familiar qualitative methods, to develop new, remote ethnographic research strategies and to examine the limitations of conducting ethnography from a distance. We consider how far we stretch ‘ethnography’ in a socially distanced context, using what we call ‘portholes of ethnography’, and we outline how our learning informs the ways in which we can adapt research approaches – driven by relationality – in times of crises

Peptide-mediated growth and dispersion of Au nanoparticles in water via sequence engineering

YesThe use of peptides to nucleate, grow, and stabilize nanoparticles in aqueous media via non-covalent interactions offers new possibilities for creating functional, water-dispersed inorganic/organic hybrid materials, particularly for Au nanoparticles. Numerous previous studies have identified peptide sequences that both possess a strong binding affinity for Au surfaces and are capable of supporting nanoparticle growth in water. However, recent studies have shown that not all such peptide sequences can produce stable dispersions of these nanoparticles. Here, via integrated experiments and molecular modeling, we provide new insights into the many factors that influence Au nanoparticle growth and stabilization in aqueous media. We define colloidal stability by the absence of visible precipitation after at least 24 hours post-synthesis. We use binding affinity measurements, nanoparticle synthesis, characterization and stabilization assays, and molecular modeling, to investigate a set of sequences based on two known peptides with strong affinity for Au. This set of biomolecules is designed to probe specific sequence and context effects using both point mutations and global reorganization of the peptides. Our data confirm, for a broader range of sequences, that Au nanoparticle/peptide binding affinity alone is not predictive of peptide-mediated colloidal stability. By comparing nanoparticle stabilization assay outcomes with molecular simulations, we establish a correlation between the colloidal stability of the Au nanoparticles and the degree of conformational diversity in the surface-adsorbed peptides. Our findings suggest future routes to engineer peptide sequences for bio-based growth and dispersion of functional nanoparticles in aqueous media.Air Office of Scientific Research, grant number FA9550-12-1-0226

When to Invest in Carbon Capture and Storage Technology: A Mathematical Model. ESRI Research Bulletin 2014/1/4

The goal of this paper is to determine the optimal time to invest in retrofitting a CCS unit onto an existing power plant in (i) a region subject to a (deterministically evolving) carbon tax, such as the carbon floor introduced in Great Britain (GB) in April 2013, and (ii) in a region where there is uncertainty in the price o

Optical control of nanoparticle catalysis influenced by photoswitch positioning in hybrid peptide capping ligands

YesHere we present an in-depth analysis of structural factors that modulate peptide-capped nanoparticle catalytic activity via optically driven structural reconfiguration of the biointerface present at the particle surface. Six different sets of peptide-capped Au nanoparticles were prepared, in which an azobenzene photoswitch was incorporated into one of two well-studied peptide sequences with known affinity for Au, each at one of three different positions: The N- or C-terminus, or mid-sequence. Changes in the photoswitch isomerization state induce a reversible structural change in the surface-bound peptide, which modulates the catalytic activity of the material. This control of reactivity is attributed to changes in the amount of accessible metallic surface area available to drive the reaction. This research specifically focuses on the effect of the peptide sequence and photoswitch position in the biomolecule, from which potential target systems for on/off reactivity have been identified. Additionally, trends associated with photoswitch position for a peptide sequence (Pd4) have been identified. Integrating the azobenzene at the N-terminus or central region results in nanocatalysts with greater reactivity in the trans and cis conformations, respectively; however, positioning the photoswitch at the C-terminus gives rise to a unique system that is reactive in the trans conformation and partially deactivated in the cis conformation. These results provide a fundamental basis for new directions in nanoparticle catalyst development to control activity in real time, which could have significant implications in the design of catalysts for multistep reactions using a single catalyst. Additionally, such a fine level of interfacial structural control could prove to be important for applications beyond catalysis, including biosensing, photonics, and energy technologies that are highly dependent on particle surface structures.Air Office of Scientific Research, grant number FA9550-12- 1-0226