Flat roofs renovation: a life cycle approach for environmental impact assessment and economic effectiveness

The high energy consumption caused by the building sector and the continuous growth and ageing of the existing housing stock show the importance of housing renovation to improve the quality of the environment. This research compares the environmental performance of flat roof systems (insulation, roofing membrane and covering layer) using Life Cycle Assessment (LCA). The aim is to give indications on how to improve the environmental performance of housing. This research uses a reference building located in the Netherlands and considers environmental impacts related to materials, energy consumption for heating and maintenance activities. It indicates impact scores for each material taking into account interconnections between the layers and between the different parts of the life cycle. It compares the environmental and economic performances of PV panels and of different materials and thermal resistance values for the insulation. These comparisons show that PV panels are convenient from an environmental and economic point of view. The same is true for the insulation layer, especially for materials as PIR (polyisocyanurate) and EPS (expanded polystyrene). It shows that energy consumption for heating causes a larger share of impact scores than production of the materials and maintenance activities. The insulation also causes larger impact scores comparing to roofing membrane and covering layer. The results show which materials are preferable for flat roof renovation and what causes the largest shares of impact. This gives indication to the roofers and to other stakeholders about how to reduce the environmental impact of the existing housing stock.

Structural and functional analysis of centromeric chromatin

Animal neocentromeres are defined as ectopic centromeres that have formed in non-centromeric locations and avoid some of the features, like the DNA satellite sequence, that normally characterize canonical centromeres. Despite this, they are stable functional centromeres inherited through generations. The only existence of neocentromeres provide convincing evidence that centromere specification is determined by epigenetic rather than sequence-specific mechanisms. For all this reasons, we used them as simplified models to investigate the molecular mechanisms that underlay the formation and the maintenance of functional centromeres. We collected human cell lines carrying neocentromeres in different positions. To investigate the region involved in the process at the DNA sequence level we applied a recent technology that integrates Chromatin Immuno-Precipitation and DNA microarrays (ChIP-on-chip) using rabbit polyclonal antibodies directed against CENP-A or CENP-C human centromeric proteins. These DNA binding-proteins are required for kinetochore function and are exclusively targeted to functional centromeres. Thus, the immunoprecipitation of DNA bound by these proteins allows the isolation of centromeric sequences, including those of the neocentromeres. Neocentromeres arise even in protein-coding genes region. We further analyzed if the increased scaffold attachment sites and the corresponding tighter chromatin of the region involved in the neocentromerization process still were permissive or not to transcription of within encoded genes. Centromere repositioning is a phenomenon in which a neocentromere arisen without altering the gene order, followed by the inactivation of the canonical centromere, becomes fixed in population. It is a process of chromosome rearrangement fundamental in evolution, at the bases of speciation. The repeat-free region where the neocentromere initially forms, progressively acquires extended arrays of satellite tandem repeats that may contribute to its functional stability. In this view our attention focalized to the repositioned horse ECA11 centromere. ChIP-on-chip analysis was used to define the region involved and SNPs studies, mapping within the region involved into neocentromerization, were carried on. We have been able to describe the structural polymorphism of the chromosome 11 centromeric domain of Caballus population. That polymorphism was seen even between homologues chromosome of the same cells. That discovery was the first described ever. Genomic plasticity had a fundamental role in evolution. Centromeres are not static packaged region of genomes. The key question that fascinates biologists is to understand how that centromere plasticity could be combined to the stability and maintenance of centromeric function. Starting from the epigenetic point of view that underlies centromere formation, we decided to analyze the RNA content of centromeric chromatin. RNA, as well as secondary chemically modifications that involve both histones and DNA, represents a good candidate to guide somehow the centromere formation and maintenance. Many observations suggest that transcription of centromeric DNA or of other non-coding RNAs could affect centromere formation. To date has been no thorough investigation addressing the identity of the chromatin-associated RNAs (CARs) on a global scale. This prompted us to develop techniques to identify CARs in a genome-wide approach using high-throughput genomic platforms. The future goal of this study will be to focalize the attention on what strictly happens specifically inside centromere chromatin.

Tecniche MonteCarlo per l'analisi di sistemi a rete

The assessment of the RAMS (Reliability, Availability, Maintainability and Safety) performances of system generally includes the evaluations of the “Importance” of its components and/or of the basic parameters of the model through the use of the Importance Measures. The analytical equations proposed in this study allow the estimation of the first order Differential Importance Measure on the basis of the Birnbaum measures of components, under the hypothesis of uniform percentage changes of parameters. The aging phenomena are introduced into the model by assuming exponential-linear or Weibull distributions for the failure probabilities. An algorithm based on a combination of MonteCarlo simulation and Cellular Automata is applied in order to evaluate the performance of a networked system, made up of source nodes, user nodes and directed edges subjected to failure and repair. Importance Sampling techniques are used for the estimation of the first and total order Differential Importance Measures through only one simulation of the system “operational life”. All the output variables are computed contemporaneously on the basis of the same sequence of the involved components, event types (failure or repair) and transition times. The failure/repair probabilities are forced to be the same for all components; the transition times are sampled from the unbiased probability distributions or it can be also forced, for instance, by assuring the occurrence of at least a failure within the system operational life. The algorithm allows considering different types of maintenance actions: corrective maintenance that can be performed either immediately upon the component failure or upon finding that the component has failed for hidden failures that are not detected until an inspection; and preventive maintenance, that can be performed upon a fixed interval. It is possible to use a restoration factor to determine the age of the component after a repair or any other maintenance action.

Transcriptional regulation and functional characterization of the tumor suppressor genes Hugl-1 and Hugl-2

Cancer is a multi-step process in which both the activation of oncogenes and the inactivation of tumor suppressor genes alter the normal cellular programs to a state of proliferation and growth. The regulation of a number of tumor suppressor genes and the mechanism underlying the tumor suppression have been intensively studied. Hugl-1 and Hugl-2, the human homologues of Drosophila lgl are shown to be down-regulated in a variety of cancers including breast, colon, lung and melanoma, but the mechanism responsible for loss of expression is not yet known. The regulation of gene expression is influenced by factors inducing or repressing transcription. The present study was focused on the identification and characterization of the active promoters of Hugl-1 and Hugl-2. Further, the regulation of the promoter and functional consequences of this regulation by specific transcription factors was analyzed. Experiments to delineate the function of the mouse homologue of Hugl-2, mgl2 using transgenic mice model were performed. This study shows that the active promoter for both Hugl-1 and Hugl-2 is located 1000bp upstream of transcription start sites. The study also provides first insight into the regulation of Hugl-2 by an important EMT transcriptional regulator, Snail. Direct binding of Snail to four E-boxes present in Hugl-2 promoter region results in repression of Hugl-2 expression. Hugl-1 and Hugl-2 plays pivotal role in establishment and maintenance of cell polarity in a diversity of cell types and organisms. Loss of epithelial cell polarity is a prerequisite for cancer progression and metastasis and is an important step in inducing EMT in cells. Regulation of Hugl-2 by Snail suggests one of the initial events towards loss of epithelial cell polarity during Snail-mediated EMT. Another important finding of this study is the induction of Hugl-2 expression can reverse the Snail-driven EMT. Inducing Hugl-2 in Snail expressing cells results in the re-expression of epithelial markers E-cadherin and Cytokeratin-18. Further, Hugl-2 also reduces the rate of tumor growth, cell migration and induces the epithelial phenotype in 3D culture model in cells expressing Snail. Studies to gain insight into the signaling pathways involved in reversing Snail-mediated EMT revealed that induction of Hugl-2 expression interferes with the activation of extracellular receptor kinase, Erk. Functional aspects of mammalian lgl in vivo was investigated by establishing mgl2 conditional knockout mice. Though disruption of mgl2 gene in hepatic tissues did not alter the growth and development, ubiquitous disruption of mgl2 gene causes embryonic lethality which is evident by the fact that no mgl2-/- mice were born.

Development of newly conceived biomimetic nano-structured biomaterials as scaffolds for bone and osteochondral regeneration

The present research thesis was focused on the development of new biomaterials and devices for application in regenerative medicine, particularly in the repair/regeneration of bone and osteochondral regions affected by degenerative diseases such as Osteoarthritis and Osteoporosis or serious traumas. More specifically, the work was focused on the synthesis and physico-chemical-morphological characterization of: i) a new superparamagnetic apatite phase; ii) new biomimetic superparamagnetic bone and osteochondral scaffolds; iii) new bioactive bone cements for regenerative vertebroplasty. The new bio-devices were designed to exhibit high biomimicry with hard human tissues and with functionality promoting faster tissue repair and improved texturing. In particular, recent trends in tissue regeneration indicate magnetism as a new tool to stimulate cells towards tissue formation and organization; in this perspective a new superparamagnetic apatite was synthesized by doping apatite lattice with di-and trivalent iron ions during synthesis. This finding was the pin to synthesize newly conceived superparamagnetic bone and osteochondral scaffolds by reproducing in laboratory the biological processes yielding the formation of new bone, i.e. the self-assembly/organization of collagen fibrils and heterogeneous nucleation of nanosized, ionically substituted apatite mimicking the mineral part of bone. The new scaffolds can be magnetically switched on/off and function as workstations guiding fast tissue regeneration by minimally invasive and more efficient approaches. Moreover, in the view of specific treatments for patients affected by osteoporosis or traumas involving vertebrae weakening or fracture, the present work was also dedicated to the development of new self-setting injectable pastes based on strontium-substituted calcium phosphates, able to harden in vivo and transform into strontium-substituted hydroxyapatite. The addition of strontium may provide an anti-osteoporotic effect, aiding to restore the physiologic bone turnover. The ceramic-based paste was also added with bio-polymers, able to be progressively resorbed thus creating additional porosity in the cement body that favour cell colonization and osseointegration.

Characterization of the Caspr2 and NLGN2 ligands: a proteomic and biochemical approach

Autism Spectrum Disorder (ASD) is a range of early-onset conditions classified as neurodevelopmental disorders, characterized by deficits in social interactions and communication, as well as by restricted interest and repetitive behaviors. Among the proteins associated with this spectrum of disease there are Caspr2, α-NRXN1, NLGN1-4. Caspr2 is involved in the clustering of K+ channels at the juxtaparanodes, where it is proposed to bind TAG-1. Recent works reported a synaptic localization of Caspr2, but little is know on its role in this compartment. NRXNs and their ligand NLGNs, instead, have a well-defined role in the formation and maintenance of synapses. Among the neuroligins, NLGN2 binds NRXNs with the lowest affinity, suggesting that it could have other not yet characterized ligands. The aim of this work was to better characterize the binding of Caspr2 to TAG-1 and to identify new potential binding partner for Caspr2 and NLGN2. Unexpectedly, using Isothermal Titration Calorimetry and co-immunoprecipitation experiments the direct association of the first two proteins could not be verified and the results indicate that the first evidences reporting it were biased by false-positive artifacts. These findings, together with the uncharacterized synaptic localization of Caspr2, made the identification of new potential binding partners for this protein necessary. To find new proteins that associate with Caspr2 and NLGN2, affinity chromatography in tandem with mass spectrometry experiments were performed. Interestingly, about 25 new potential partners were found for these two proteins and NLGN1, that was originally included as a control: 5 of those, namely SFRP1, CLU, APOE, CNTN1 and TNR, were selected for further investigations. Only the association of CLU to NLGN2 was confirmed. In the future, screenings of the remaining candidates have to be carried out and the functional role for the proposed NLGN2-CLU complex has to be studied.

Aggression and its function as a hub mediating host defense against the slavemaking ant Protomognathus americanus

In meiner Dissertation beschäftigte ich mich mit unterschiedlichen Verteidungsstrategien, derenrnEffektivität und Evolution, der Ameisenart Temnothorax longispinosus (“Sklaven”), gegenüberrneinem sozialen Parasiten - der nahverwandten, sklavenhaltenden Art Protomognathusrnamericanus (“Sklavenhalter”). Wir entdeckten eine neue Kategorie der Verteidigungsstrategie,rnwelche es dem Wirten ermöglicht, flexibel auf die nicht vorhersagbaren Angriffe des Parasitenrnzu reagieren. Darüber hinaus erforschten wir, wie die Wirte ihre kollektive Verteidigung an einernVielzahl unterschiedlicher Angreifer anpassen können. Wir konnten feststellen, dass Wirte in derrnLage sind ihre kollektive Verteidigung dem Grad der Bedrohung anzupassen. Dies weist daraufrnhin, dass Selektion die Verteidigung gegen unterschiedliche Typen von Angreifern voneinanderrnunabhängig beeinflussen könnte. In einer dritten Studie belegten wir experimentell, dass diernParasiten die Evolution der Kolonieaggressivität der Wirtsart direkt beeinflussen. Die letztenrnbeiden Publikationen beschäftigten sich mit Sklavenrebellion, einer rätselhaftenrnVerteidigungsstrategie, da noch unklar ist, wie eine Eigenschaft von nicht reproduzierendenrnIndividuen vererbt werden kann. In einer Metaanalyse konnten wir die weite Verbreitung undrnhohe Variabilität dieser Eigenschaft dokumentieren, und fanden Hinweise, dassrnVerwandtenselektion eine mögliche Erklärung für die Evolution dieses Merkmals darstellenrnkönnte.

Sustainable improvement of water networks : to achieve best decisions for rehabilitation plans using advanced GIS and statistical techniques

Many of developing countries are facing crisis in water management due to increasing of population, water scarcity, water contaminations and effects of world economic crisis. Water distribution systems in developing countries are facing many challenges of efficient repair and rehabilitation since the information of water network is very limited, which makes the rehabilitation assessment plans very difficult. Sufficient information with high technology in developed countries makes the assessment for rehabilitation easy. Developing countries have many difficulties to assess the water network causing system failure, deterioration of mains and bad water quality in the network due to pipe corrosion and deterioration. The limited information brought into focus the urgent need to develop economical assessment for rehabilitation of water distribution systems adapted to water utilities. Gaza Strip is subject to a first case study, suffering from severe shortage in the water supply and environmental problems and contamination of underground water resources. This research focuses on improvement of water supply network to reduce the water losses in water network based on limited database using techniques of ArcGIS and commercial water network software (WaterCAD). A new approach for rehabilitation water pipes has been presented in Gaza city case study. Integrated rehabilitation assessment model has been developed for rehabilitation water pipes including three components; hydraulic assessment model, Physical assessment model and Structural assessment model. WaterCAD model has been developed with integrated in ArcGIS to produce the hydraulic assessment model for water network. The model have been designed based on pipe condition assessment with 100 score points as a maximum points for pipe condition. As results from this model, we can indicate that 40% of water pipeline have score points less than 50 points and about 10% of total pipes length have less than 30 score points. By using this model, the rehabilitation plans for each region in Gaza city can be achieved based on available budget and condition of pipes. The second case study is Kuala Lumpur Case from semi-developed countries, which has been used to develop an approach to improve the water network under crucial conditions using, advanced statistical and GIS techniques. Kuala Lumpur (KL) has water losses about 40% and high failure rate, which make severe problem. This case can represent cases in South Asia countries. Kuala Lumpur faced big challenges to reduce the water losses in water network during last 5 years. One of these challenges is high deterioration of asbestos cement (AC) pipes. They need to replace more than 6500 km of AC pipes, which need a huge budget to be achieved. Asbestos cement is subject to deterioration due to various chemical processes that either leach out the cement material or penetrate the concrete to form products that weaken the cement matrix. This case presents an approach for geo-statistical model for modelling pipe failures in a water distribution network. Database of Syabas Company (Kuala Lumpur water company) has been used in developing the model. The statistical models have been calibrated, verified and used to predict failures for both networks and individual pipes. The mathematical formulation developed for failure frequency in Kuala Lumpur was based on different pipeline characteristics, reflecting several factors such as pipe diameter, length, pressure and failure history. Generalized linear model have been applied to predict pipe failures based on District Meter Zone (DMZ) and individual pipe levels. Based on Kuala Lumpur case study, several outputs and implications have been achieved. Correlations between spatial and temporal intervals of pipe failures also have been done using ArcGIS software. Water Pipe Assessment Model (WPAM) has been developed using the analysis of historical pipe failure in Kuala Lumpur which prioritizing the pipe rehabilitation candidates based on ranking system. Frankfurt Water Network in Germany is the third main case study. This case makes an overview for Survival analysis and neural network methods used in water network. Rehabilitation strategies of water pipes have been developed for Frankfurt water network in cooperation with Mainova (Frankfurt Water Company). This thesis also presents a methodology of technical condition assessment of plastic pipes based on simple analysis. This thesis aims to make contribution to improve the prediction of pipe failures in water networks using Geographic Information System (GIS) and Decision Support System (DSS). The output from the technical condition assessment model can be used to estimate future budget needs for rehabilitation and to define pipes with high priority for replacement based on poor condition. rn

Linking rural tourism to agriculture. Evidences from comparative case studies in Kosovo, Italy and Spain

Rural tourism has been widely promoted in the European Union as an effective measure counteracting economic and social challenges facing rural areas especially those with declining agriculture economies. Particularly its role is seen in provision and maintenance of public goods which are more and more demanded by the public and considered in the policymaking. In Kosovo, rural tourism has been developed through the support of the international organizations and private sector initiatives, with primary aim to generate additional income for rural households and sustainable management of natural and cultural resources. Anyhow, it could be stated that the use of territorial capital to enhance the quality of the tourist offer and undertake promotion at wider circles of people has not been well explored so far, particularly possible links with agriculture that would satisfy visitors demand. In this regard this research study analyzes involvement of local stakeholders and use of territorial capital to develop tourist offer in rural areas of Kosovo. Beside, study applies comparative approach with other two areas of the European Union, Appennino Bolognese in Italy and Alpujara in Spain, to understand and compare the process of rural tourism development and demand characteristics between Kosovo and these areas. A survey has been conducted in all three study areas with rural tourism visitors to understand their preferences for public and private goods and services when visiting rural areas and the role of agriculture in sustaining rural tourism. Results show that there is a potential to link rural tourism with agriculture in Kosovo, which would help in sustaining agriculture and add additional value to local food products, which in return would enhance the tourist offer and make it more attractive for the visitors but also for the farmers as an additional revenue generating sector.

Intraflagellar transport in the developing and mature vertebrate retina

Intraflagellar transport (IFT) is required for the assembly and maintenance of cilia. In this study we analyzed the subcellular localization of IFT proteins in retinal cells by correlative high-resolution immunofluorescence and immunoelectron microscopy. The rod photoreceptor cell was used as a model system to analyze protein distribution in cilia. To date the expression of IFT proteins has been described in the ciliary region without deciphering the precise spatial and temporal subcellular localization of IFT proteins, which was the focus of my work. rnThe establishment of the pre-embedding immunoelectron method was an important first step for the present doctoral thesis. Results of this work reveal the differential localization of IFT20, IFT52, IFT57, IFT88, IFT140 in sub-ciliary compartments and also their presence in non-ciliary compartments of retinal photoreceptor cells. Furthermore, the localization of IFT20, IFT52 and IFT57 in dendritic processes of non-ciliated neurons indicates that IFT protein complexes also operate in non-ciliated cells and may participate in intracellular vesicle trafficking in eukaryotic cells in general.rnIn addition, we have investigated the involvement of IFT proteins in the ciliogenesis of vertebrate photoreceptor cilia. Electron microscopy analyses revealed six morphologically distinct stages. The first stages are characterized by electron dense centriolar satellites and a ciliary vesicle, while the formation of a ciliary shaft and of the light sensitive outer segment disks are features of the later stages. IFT proteins were expressed during all stages of photoreceptor cell development and found to be associated with the ciliary apparatus. In addition to the centriole and basal body IFT proteins are present in the photoreceptor cytoplasm, associated with centriolar satellites, post-Golgi vesicles and with the ciliary vesicle. Therewith the data provide an evidence for the involvement of IFT proteins during ciliogenesis, including the formation of the ciliary vesicle and the elongation of the primary cilium of photoreceptor cells. Moreover, the cytoplasmic localization of IFT proteins in the absence of a ciliary shaft in early stages of ciliogenesis indicates roles of IFT proteins beyond their well-established function for IFT in mature cilia and flagella. rn

BPAG1 isoform-b: Complex distribution pattern in striated and heart muscle and association with plectin and α-actinin

BPAG1-b is the major muscle-specific isoform encoded by the dystonin gene, which expresses various protein isoforms belonging to the plakin protein family with complex, tissue-specific expression profiles. Recent observations in mice with either engineered or spontaneous mutations in the dystonin gene indicate that BPAG1-b serves as a cytolinker important for the establishment and maintenance of the cytoarchitecture and integrity of striated muscle. Here, we studied in detail its distribution in skeletal and cardiac muscles and assessed potential binding partners. BPAG1-b was detectable in vitro and in vivo as a high molecular mass protein in striated and heart muscle cells, co-localizing with the sarcomeric Z-disc protein alpha-actinin-2 and partially with the cytolinker plectin as well as with the intermediate filament protein desmin. Ultrastructurally, like alpha-actinin-2, BPAG1-b was predominantly localized at the Z-discs, adjacent to desmin-containing structures. BPAG1-b was able to form complexes with both plectin and alpha-actinin-2, and its NH(2)-terminus, which contains an actin-binding domain, directly interacted with that of plectin and alpha-actinin. Moreover, the protein level of BPAG1-b was reduced in muscle tissues from plectin-null mutant mice versus wild-type mice. These studies provide new insights into the role of BPAG1-b in the cytoskeletal organization of striated muscle.

MET inhibition in tumor cells by PHA665752 impairs homologous recombination repair of DNA double strand breaks

Abnormal activation of cellular DNA repair pathways by deregulated signaling of receptor tyrosine kinase systems has broad implications for both cancer biology and treatment. Recent studies suggest a potential link between DNA repair and aberrant activation of the hepatocyte growth factor receptor Mesenchymal-Epithelial Transition (MET), an oncogene that is overexpressed in numerous types of human tumors and considered a prime target in clinical oncology. Using the homologous recombination (HR) direct-repeat direct-repeat green fluorescent protein ((DR)-GFP) system, we show that MET inhibition in tumor cells with deregulated MET activity by the small molecule PHA665752 significantly impairs in a dose-dependent manner HR. Using cells that express MET-mutated variants that respond differentially to PHA665752, we confirm that the observed HR inhibition is indeed MET-dependent. Furthermore, our data also suggest that decline in HR-dependent DNA repair activity is not a secondary effect due to cell cycle alterations caused by PHA665752. Mechanistically, we show that MET inhibition affects the formation of the RAD51-BRCA2 complex, which is crucial for error-free HR repair of double strand DNA lesions, presumably via downregulation and impaired translocation of RAD51 into the nucleus. Taken together, these findings assist to further support the role of MET in the cellular DNA damage response and highlight the potential future benefit of MET inhibitors for the sensitization of tumor cells to DNA damaging agents.

Different molecular and structural adaptations with eccentric and conventional strength training in elderly men and women

Reprogramming of gene expression contributes to structural and functional adaptation of muscle tissue in response to altered use. The aim of this study was to investigate mechanisms for observed improvements in leg extension strength, gain in relative thigh muscle mass and loss of body and thigh fat content in response to eccentric and conventional strength training in elderly men (n = 14) and women (n = 14; average age of the men and women: 80.1 ± 3.7 years) by means of structural and molecular analyses. Biopsies were collected from m. vastus lateralis in the resting state before and after 12 weeks of training with two weekly resistance exercise sessions (RET) or eccentric ergometer sessions (EET). Gene expression was analyzed using custom-designed low-density PCR arrays. Muscle ultrastructure was evaluated using EM morphometry. Gain in thigh muscle mass was paralleled by an increase in muscle fiber cross-sectional area (hypertrophy) with RET but not with EET, where muscle growth is likely occurring by the addition of sarcomeres in series or by hyperplasia. The expression of transcripts encoding factors involved in muscle growth, repair and remodeling (e.g., IGF-1, HGF, MYOG, MYH3) was increased to a larger extent after EET than RET. MicroRNA 1 expression was decreased independent of the training modality, and was paralleled by an increased expression of IGF-1 representing a potential target. IGF-1 is a potent promoter of muscle growth, and its regulation by microRNA 1 may have contributed to the gain of muscle mass observed in our subjects. EET depressed genes encoding mitochondrial and metabolic transcripts. The changes of several metabolic and mitochondrial transcripts correlated significantly with changes in mitochondrial volume density. Intramyocellular lipid content was decreased after EET concomitantly with total body fat. Changes in intramyocellular lipid content correlated with changes in body fat content with both RET and EET. In the elderly, RET and EET lead to distinct molecular and structural adaptations which might contribute to the observed small quantitative differences in functional tests and body composition parameters. EET seems to be particularly convenient for the elderly with regard to improvements in body composition and strength but at the expense of reducing muscular oxidative capacity.

A Divided City in a Common Market: EU Citizenship and Everyday Instrumentalities on the Polish-German Border

Based on an ethnographic case study in the border cities of Frankfurt (Oder), Germany and Słubice, Poland, this article explores the construction and maintenance of ethnic difference within the transnational economic and social spaces created by the European Union's common market. Through an examination of three domains of cross-border citizenship practice - shopping and consumption, housing and work - this article argues that even as the European Union deploys policies aimed at creating de-territorialised and supranational forms of identity and citizenship, economic asymmetries and hierarchies of value embedded within these policies grant rights differentially in ways that continue to be linked to ethnicity and nationality.

Human neural stem cells enhance structural plasticity and axonal transport in the ischaemic brain

Stem cell transplantation promises new hope for the treatment of stroke although significant questions remain about how the grafted cells elicit their effects. One hypothesis is that transplanted stem cells enhance endogenous repair mechanisms activated after cerebral ischaemia. Recognizing that bilateral reorganization of surviving circuits is associated with recovery after stroke, we investigated the ability of transplanted human neural progenitor cells to enhance this structural plasticity. Our results show the first evidence that human neural progenitor cell treatment can significantly increase dendritic plasticity in both the ipsi- and contralesional cortex and this coincides with stem cell-induced functional recovery. Moreover, stem cell-grafted rats demonstrated increased corticocortical, corticostriatal, corticothalamic and corticospinal axonal rewiring from the contralesional side; with the transcallosal and corticospinal axonal sprouting correlating with functional recovery. Furthermore, we demonstrate that axonal transport, which is critical for both proper axonal function and axonal sprouting, is inhibited by stroke and that this is rescued by the stem cell treatment, thus identifying another novel potential mechanism of action of transplanted cells. Finally, we established in vitro co-culture assays in which these stem cells mimicked the effects observed in vivo. Through immunodepletion studies, we identified vascular endothelial growth factor, thrombospondins 1 and 2, and slit as mediators partially responsible for stem cell-induced effects on dendritic sprouting, axonal plasticity and axonal transport in vitro. Thus, we postulate that human neural progenitor cells aid recovery after stroke through secretion of factors that enhance brain repair and plasticity.