Control of morphological properties of porous biodegradable scaffolds processed by supercritical CO2 foaming

A low cost supercritical CO foaming rig with a novel design has been used to prepare fully interconnected and highly porous biodegradable scaffolds with controllable pore size and structure that can promote cancellous bone regeneration. Porous polymer scaffolds have been produced by plasticising the polymer with high pressure CO and by the formation of a porous structure following the escape of CO from the polymer. Although, control over pore size and structure has been previously reported as difficult with this process, the current study shows that control is possible. The effects of processing parameters such as CO saturation pressure, time and temperature and depressurisation rate on the morphological properties, namely porosity, pore interconnectivity, pore size and wall thickness- of the scaffolds have been investigated. Poly(d,l)lactic acid was used as the biodegradable polymer. The surfaces and internal morphologies of the poly(d,l)lactic acid scaffolds were examined using optical microscope and micro computed tomography. Preosteoblast human bone cells were seeded on the porous scaffolds in vitro to assess cell attachment and viability. The scaffolds showed a good support for cell attachment, and maintained cell viability throughout 7 days in culture. This study demonstrated that the morphology of the porous structure can be controlled by varying the foaming conditions, allowing the porous scaffolds to be used in various tissue engineering applications.

The Map of Watchful Architecture 2.0:Defensive forms along Ireland's border

For The Map of Watchful Architecture I only concerned myself with defensive architecture along the Border. As the map followed a border it came out as a wavy line of points. This was largely artificial, I only charted architecture within the Border corridor, but was not entirely artificial. That linear landscape has long been staked-out by the regularity of certain kinds of architecture. The 1st/2nd century Black Pig’s Dyke and Dorsey correspond with today’s Border. The concentration of souterrains in north Louth indicate that it may have been a volatile interface zone in later centuries. In 1618 Londonderry and its walls were built. Further north and two centuries later, Martello Towers were constructed to watch over Lough Foyle. During the Second World War pillboxes and observation posts were manned along the Border, close to what was now an international frontier. Then came the Operation Banner installations built during The Troubles. All this adds up to be one of the longest unbroken traditions of defensive architecture anywhere in Western Europe, a tradition some thought finally broken as the last of the Operation Banner towers were de-installed in 2007. But, take a bus south across the Border and you will often be pulled over by the Garda Síochána. They ID check the passengers in an attempt to stop illegal immigration via the UK. What about illegal immigrants who walk through the fields or along quiet lanes? They will have understood the Border is not really how it seems on most maps. It is not a solid line, it is a row of points.

Islands: Nature and Culture

Islands are contradictory places: they can be remote, mysterious spots, or lively centres of holiday revelry. They are associated alternately with escape, imprisonment, holiday and exile, and their exotic, otherworldly beauty has inspired artists and writers across the centuries. Islands have been sites of immense political, creative and scientific importance from Charles Darwin's enlightening voyage to the Gálapagos Islands, which resulted in his groundbreaking theory of evolution, to the moat-encased prisons incarcerating the world's most dangerous convicts.
Despite the common view of islands as earthly paradises, their often small size means they have restricted resources and limited opportunities for their inhabitants to thrive. In response, islanders have welcomed or sternly rejected, the fresh opportunities offered by turning their homes into tourist destinations. For people seeking beautiful landscapes, solitude or exciting adventure, islands are the most popular holiday spots in the world. They entice the rich and famous, and their allure has provided refuge and inspiration for artists and writers, from Paul Gauguin in Tahiti to George Orwell on Jura in the Hebrides, and general visitors alike.
Filled with illustrations, Islands is a comprehensive exploration of the geographical and cultural aspects of island life – their habitations and environments, their permanent residents and vast transitional populace, their colonial history and their enduring appeal to people around then world.

Mutations in the H, F, or M proteins can facilitate resistance of measles virus to neutralizing human anti-MV sera

Although there is currently no evidence of emerging strains of measles virus (MV) that can resist neutralization by the anti-MV antibodies present in vaccinees, certain mutations in circulating wt MV strains appear to reduce the efficacy of these antibodies. Moreover, it has been hypothesized that resistance to neutralization by such antibodies could allow MV to persist. In this study, we use a novel in vitro system to determine the molecular basis of MV's resistance to neutralization. We find that both wild-type and laboratory strain MV variants that escape neutralization by anti-MV polyclonal sera possess multiple mutations in their H, F, and M proteins. Cytometric analysis of cells expressing viral escape mutants possessing minimal mutations and their plasmid-expressed H, F, and M proteins indicates that immune resistance is due to particular mutations that can occur in any of these three proteins that affect at distance, rather than directly, the native conformation of the MV-H globular head and hence its epitopes. A high percentage of the escape mutants contain mutations found in cases of Subacute Sclerosing Panencephalitis (SSPE) and our results could potentially shed light on the pathogenesis of this rare fatal disease.

Dynamic properties of bright points in an active region

Context. Bright points (BPs) are small-scale, magnetic features ubiquitous across the solar surface. Previously, we have observed and noted their properties for quiet Sun regions. Here, we determine the dynamic properties of BPs using simultaneous quiet Sun and active region data.

Aims. The aim of this paper is to compare the properties of BPs in both active and quiet Sun regions and to determine any difference in the dynamics and general properties of BPs as a result of the varying magnetic activity within these two regions.

Methods. High spatial and temporal resolution G-band observations of active region AR11372 were obtained with the Rapid Oscillations in the Solar Atmosphere instrument at the Dunn Solar Telescope. Three subfields of varying polarity and magnetic flux density were selected with the aid of magnetograms obtained from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory. Bright points within these subfields were subsequently tracked and analysed.

Results. It is found that BPs within active regions display attenuated velocity distributions with an average horizontal velocity of ~0.6 km s-1, compared to the quiet region which had an average velocity of 0.9 km s-1. Active region BPs are also ~21% larger than quiet region BPs and have longer average lifetimes (~132 s) than their quiet region counterparts (88 s). No preferential flow directions are observed within the active region subfields. The diffusion index (γ) is estimated at ~1.2 for the three regions.

Conclusions. We confirm that the dynamic properties of BPs arise predominately from convective motions. The presence of stronger field strengths within active regions is the likely reason behind the varying properties observed. We believe that larger amounts of magnetic flux will attenuate BP velocities by a combination of restricting motion within the intergranular lanes and by increasing the number of stagnation points produced by inhibited convection. Larger BPs are found in regions of higher magnetic flux density and we believe that lifetimes increase in active regions as the magnetic flux stabilises the BPs.

Dendrons with spermine surface groups as potential building blocks for nonviral vectors in gene therapy

This paper investigates a series of dendrons based on the Newkome dendritic scaffold that displays a naturally occurring polyamine (spermine) on their surface. These dendrons have previously been shown to interact with DNA in a generation dependent manner with the more highly branched dendrons exhibiting a strong multivalency effect for the spermine surface groups. In this paper, we investigate the ability of these dendrons to transfect DNA into cells (human breast carcinoma cells, MDA-MB-231, and murine myoblast cells, C2C12) as determined by the luciferase assay. Although the dendrons are unable to transfect DNA in their own right, they are capable of delivering DNA in vitro when administered with chloroquine, which assists with escape from endocytic vesicles. The cytotoxicity of the dendrons was determined using the XTT assay, and it was shown that the dendrons were nontoxic either alone or in the presence of DNA. However, when administered with DNA and chloroquine, the most highly branched dendron did exhibit some cytotoxicity. This paper elucidates the relationship between in vitro transfection efficiency and toxicity. While transfection efficiencies are modest, the low toxicity of the dendrons, both in their own right, and in the presence of DNA, provides encouragement that this type of building block, which has a relatively high affinity for DNA, will provide a useful starting point for the further synthetic development of more effective gene transfection agents.

Infrastructure and the Architectures of Modernity in Ireland 1916-2016

At the formation of the new Republic of Ireland, the construction of new infrastructures was seen as an essential element in the building of the new nation, just as the adoption of international style modernism in architecture was perceived as a way to escape the colonial past. Accordingly, infrastructure became the physical manifestation, the concrete identity of these objectives and architecture formed an integral part of this narrative. Moving between scales and from artefact to context, Infrastructure and the Architectures of Modernity in Ireland 1916-2016 provides critical insights and narratives on what is a complex and hitherto overlooked landscape, one which is often as much international as it is Irish. In doing so, it explores the interaction between the universalising and globalising tendencies of modernisation on one hand and the textures of local architectures on the other.

The book shows how the nature of technology and infrastructure is inherently cosmopolitan. Beginning with the building of the heroic Shannon hydro-electric facility at Ardnacrusha by the German firm of Siemens-Schuckert in the first decade of independence, Ireland became a point of varying types of intersection between imported international expertise and local need. Meanwhile, at the other end of the century, by the year 2000, Ireland had become one of the most globalized countries in the world, site of the European headquarters of multinationals such as Google and Microsoft. Climatically and economically expedient to the storing and harvesting of data, Ireland has subsequently become a repository of digital information farmed in large, single-storey sheds absorbed into anonymous suburbs. In 2013, it became the preferred site for Intel to design and develop its new microprocessor chip: the Galileo. The story of the decades in between, of shifts made manifest in architecture and infrastructure from the policies of economic protectionism, to the opening up of the country to direct foreign investment and the embracing of the EU, is one of the influx of technologies and cultural references into a small country on the edges of Europe as Ireland became both a launch-pad and testing ground for a series of aspects of designed modernity.

Stress in parents of children born very preterm is predicted by child externalising behaviour and parent coping at age 7 years

Objective: To examine factors which predict parenting stress in a longitudinal cohort of children born very preterm seen at age seven years.
Methods: We recruited 100 very preterm (< 32 weeks GA) child-parent dyads and a control group of 50 term-born dyads born between 2001 and 2004 with follow-up at seven years. Parents completed the Parenting Stress Index, Ways of Coping Questionnaire, Child Behavior Check List, Beck Depression Inventory and the State Trait Anxiety Inventory questionnaires. Child IQ was assessed using the Wechsler Intelligence Scale-IV.
Results: After controlling for maternal education, parents of preterm children (95% CI, 111.1 to 121.4) scored higher (p = .027) on the Parenting Stress Index than term born controls (95% CI, 97.8 to 113.2). Regression analyses showed that child externalising behaviour, sex and parent escape/avoidance coping style, predicted higher parenting stress in the preterm group. Parents of preterm girls expressed higher levels of stress than those of boys. 
Conclusions: Maladaptive coping strategies contribute to greater stress in parents of very preterm children. Our findings suggest that these parents need support for many years after birth of a very preterm infant.

Session organiser/chair: Architecture, Infrastructure and the Making of Modern Ireland

‘A free Ireland would drain the bogs, would harness the rivers, would plant the wastes, would nationalise the railways and the waterways, would improve agriculture, would protect fisheries, would foster industries, would promote commerce, and beautify the cities …’ (Padraig Pearse, ‘From a Hermitage’, 1913)

Somewhat unusually in his often romantic writings Padraig Pearse – poet, pedagogue and revolutionary – chose to describe the future of an independent Ireland in terms of infrastructure and technological processes. Terence Brown’s locating of this excerpt at the beginning his seminal work Ireland: A Social and Cultural History 1922-2002 highlights the simultaneous and interlinking construction of both a new physical and cultural landscape for an independent modern nation. Lacking any significant industrial complex, the construction of new infrastructures in Ireland was seen throughout the 20th century as a key element in the building of the new State, just as the adoption of an international style modernism in architecture was perceived as a way to escape the colonial past. For Paul N. Edwards modernity and infrastructure are intimately connected.

‘infrastructures simultaneously shape and are shaped – in other words, co-construct – the condition of modernity. By linking macro, meso, and micro scales of time, space and social organisation, they form the stable foundation of modern social worlds’ (2003: 186).
Simultaneously omnipresent and invisible – infra means beneath – Edwards also points out that infrastructure tends only to become apparent when it is either new or broken. Interpreting the meso scale as being that of the building, this session calls for papers that critically and analytically investigate aspects of the architectures of infrastructure in 20th-century Ireland. Like the territory they explore these papers may range across scales to oscillate between a concern for the artefact and its physical landscape, and the larger, often hidden systems and networks that co-define this architecture.

Infra-Éireann: Making Ireland Modern - Irish Pavilion for the 14th Architectural biennale, Venice 2014.

After an open competition, we were selected to commission, curate and design the Irish pavilion for the Venice biennale 2014. Our proposal engage with the role of infrastructure and architecture in the cultural development of the new Irish state 1914-2014. This curatorial programme was realised in a demountable, open matrix pavilion measuring 12 x 5 x 6 metres.

How modernity is absorbed into national cultures usually presupposes an attachment to previous conditions and a desire to reconcile the two. In an Irish context, due to the processes of de-colonisation and political independence, this relationship is more complicated.

In 1914, Ireland was largely agricultural and lacked any significant industrial complex. The construction of new infrastructures after independence in 1921 became central to the cultural imagining of the new nation. The adoption of modernist architecture was perceived as a way to escape the colonial past. As the desire to reconcile cultural and technological aims developed, these infrastructures became both the physical manifestation and concrete identity of the new nation with architecture an essential element in this construct.

Technology and infrastructure are inherently cosmopolitan. Beginning with the Shannon hydro-electric facility at Ardnacrusha (1929) involving the German firm of Siemens-Schuckert, Ireland became a point of various intersections between imported international expertise and local need. By the turn of the last century, it had become one of the most globalised countries in the world, site of the European headquarters of multinationals such as Google and Microsoft. Climatically and economically expedient to the storing and harvesting of data, Ireland has subsequently become an important repository of digital information farmed in large, single-storey sheds absorbed into dispersed suburbs. In 2013, it became the preferred site for Intel to design and develop its new microprocessor board, the Galileo, a building block for the internet of things.

The story of the decades in between, of shifts made manifest in architecture and infrastructure, from the policies of economic protectionism to the embracing of the EU is one of the influx of technologies and cultural references into a small country on the edges of Europe: Ireland as both a launch-pad and testing ground for a series of aspects of designed modernity.

HDAC Inhibition Overcomes Acute Resistance to MEK Inhibition in BRAF-Mutant Colorectal Cancer by Downregulation of c-FLIPL

Purpose: Activating mutations in the BRAF oncogene are found in 8% to 15% of colorectal cancer patients and have been associated with poor survival. In contrast with BRAF-mutant (MT) melanoma, inhibition of the MAPK pathway is ineffective in the majority of BRAFMT colorectal cancer patients. Therefore, identification of novel therapies for BRAFMT colorectal cancer is urgently needed.

Experimental Design: BRAFMT and wild-type (WT) colorectal cancer models were assessed in vitro and in vivo. Small-molecule inhibitors of MEK1/2, MET, and HDAC were used, overexpression and siRNA approaches were applied, and cell death was assessed by flow cytometry, Western blotting, cell viability, and caspase activity assays.

Results: Increased c-MET-STAT3 signaling was identified as a novel adaptive resistance mechanism to MEK inhibitors (MEKi) in BRAFMT colorectal cancer models in vitro and in vivo. Moreover, MEKi treatment resulted in acute increases in transcription of the endogenous caspase-8 inhibitor c-FLIPL in BRAFMT cells, but not in BRAFWT cells, and inhibition of STAT3 activity abrogated MEKi-induced c-FLIPL expression. In addition, treatment with c-FLIP–specific siRNA or HDAC inhibitors abrogated MEKi-induced upregulation of c-FLIPL expression and resulted in significant increases in MEKi-induced cell death in BRAFMT colorectal cancer cells. Notably, combined HDAC inhibitor/MEKi treatment resulted in dramatically attenuated tumor growth in BRAFMT xenografts.

Conclusions: Our findings indicate that c-MET/STAT3-dependent upregulation of c-FLIPL expression is an important escape mechanism following MEKi treatment in BRAFMT colorectal cancer. Thus, combinations of MEKi with inhibitors of c-MET or c-FLIP (e.g., HDAC inhibitors) could be potential novel treatment strategies for BRAFMT colorectal cancer.

Ellerman Bombs with Jets: Cause and Effect

Ellerman Bombs (EBs) are thought to arise as a result of photospheric magnetic reconnection. We use data from the Swedish 1-m Solar Telescope(SST), to study EB events on the solar disk and at the limb. Both datasets show that EBs are connected to the foot-points of forming chromospheric jets. The limb observations show that a bright structure in the H$\alpha$ blue wing connects to the EB initially fuelling it,leading to the ejection of material upwards. The material moves along a loop structure where a newly formed jet is subsequently observed in the red wing of H$\alpha$. In the disk dataset, an EB initiates a jet which propagates away from the apparent reconnection site within the EB flame.The EB then splits into two, with associated brightenings in the inter-granular lanes (IGLs). Micro-jets are then observed, extending to500 km with a lifetime of a few minutes. Observed velocities of themicro-jets are approximately 5-10 km s$^{-1}$, while their chromospheric counterparts range from 50-80 km s$^{-1}$. MURaM simulations of quiet Sun reconnection show that micro-jets with similar properties to that of the observations follow the line of reconnection in the photosphere,with associated H$\alpha$ brightening at the location of increased temperature.

Turbulent Fluctuations in G-band and K-line Intensities Observed with the Rapid Oscillations in the Solar Atmosphere (ROSA) Instrument

Using the Rapid Oscillation in the Solar Atmosphere (ROSA) instrument at the Dunn Solar Telescope we have found that the spectra of fluctuations of the G-band (cadence 1.05 s) and Ca II K-line (cadence 4.2 s) intensities show correlated fluctuations above white noise out to frequencies beyond 300 mHz and up to 70 mHz, respectively. The noise-corrected G-band spectrum presents a scaling range (Ultra High Frequency “UHF”) for f = 25-100 mHz, with an exponent consistent with the presence of turbulent motions. The UHF power, is concentrated at the locations of magnetic bright points in the intergranular lanes, it is highly intermittent in time and characterized by a positive kurtosis κ. Combining values of G-band and K-line intensities, the UHF power, and κ, reveals two distinct “states” of the internetwork solar atmosphere. State 1, with κ ≍ 6, which includes almost all the data, is characterized by low intensities and low UHF power. State 2, with κ ≍ 3, including a very small fraction of the data, is characterized by high intensities and high UHF power. Superposed epoch analysis shows that for State 1, the K-line intensity presents 3.5 min chromospheric oscillations with maxima occurring 21 s after G-band intensity maxima implying a 150-210 km effective height difference. For State 2, the G-band and K-line intensity maxima are simultaneous, suggesting that in the highly magnetized environment sites of G-band and K-line emission may be spatially close together. Analysis of observations obtained with Hinode/SOT confirm a scaling range in the G-band spectrum up to 53 mHz also consistent with turbulent motions as well as the identification of two distinct states in terms of the H-line intensity and G-band power as functions of G-band intensity.

Rapid Oscillations in the Solar Atmosphere: Spectra and Physical Effects

High-frequency fluctuations are observed with the Rapid Oscillations in the Solar Atmosphere (ROSA) instrument (Jess et al. 2010, Solar Phys, 261, 363) at the Dunn Solar Telescope. This can produce simultaneous observations in up to six channels, at different heights in the photosphere and chromosphere, at an unprecedentedly high cadence of 0.5 seconds, and at a spatial resolution of 100 km after photometrically correct speckle reconstruction. Here we concentrate on observations at two levels. The first is in the G-band of the CH radical at 4305.5Å, bandpass 9.2Å, with height of formation z <250 km at a cadence of 0.525 sec corresponding to Nyquist frequency 950 mHz. The second is in the Ca II K-line core at 3933.7Å, bandpass 1.0Å, with height of formation z <1300 km, and cadence 4.2 sec giving Nyquist frequency 120 mHz. The data span 53 min, and the maximum field of view is 45 Mm. The data were taken on 28 May 2009 in internetwork and network near disk center. Using both Fourier and Morlet wavelet methods we find evidence in the G-band spectra for intensity fluctuations above noise out to frequencies f >> 100 mHz. The K-line signal is noisier and is seen only for f <50 mHz. With wavelet techniques we find that G-band spectral power with 20 <f <100 mHz is clearly concentrated in the intergranular lanes and especially at the locations of magnetic elements indicated by G-band bright points. This wavelet power is highly intermittent in time. By cross-correlating the data we find that pulses of high-frequency G-band power in the photosphere tend to be followed by increases in K-line emission in the chromosphere with a time lag of about 2 min.

Three motAB stator gene products in Bdellovibrio bacteriovorus contribute to motility of a single flagellum during predatory and prey-independent growth

The predatory bacterium Bdellovibrio bacteriovorus uses flagellar motility to locate regions rich in Gram-negative prey bacteria, colliding and attaching to prey and then ceasing flagellar motility. Prey are then invaded to form a "bdelloplast" in a type IV pilus-dependent process, and prey contents are digested, allowing Bdellovibrio growth and septation. After septation, Bdellovibrio flagellar motility resumes inside the prey bdelloplast prior to its lysis and escape of Bdellovibrio progeny. Bdellovibrio can also grow slowly outside prey as long flagellate host-independent (HI) cells, cultured on peptone-rich media. The B. bacteriovorus HD100 genome encodes three pairs of MotAB flagellar motor proteins, each of which could potentially form an inner membrane ion channel, interact with the FliG flagellar rotor ring, and produce flagellar rotation. In 2004, Flannagan and coworkers (R. S. Flannagan, M. A. Valvano, and S. F. Koval, Microbiology 150:649-656, 2004) used antisense RNA and green fluorescent protein (GFP) expression to downregulate a single Bdellovibrio motA gene and reported slowed release from the bdelloplast and altered motility of the progeny. Here we inactivated each pair of motAB genes and found that each pair contributes to motility, both predatorily, inside the bdelloplast and during HI growth; however, each pair was dispensable, and deletion of no pair abolished motility totally. Driving-ion studies with phenamil, carbonyl cyanide m-chlorophenylhydrazone (CCCP), and different pH and sodium conditions indicated that all Mot pairs are proton driven, although the sequence similarities of each Mot pair suggests that some may originate from halophilic species. Thus, Bdellovibrio is a "dedicated motorist," retaining and expressing three pairs of mot genes.