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41.
This monograph reports on a study comparing the regulation of internal housing space in Italy – since the introduction of broad, generic standards in 1975 – and in England, where there are no universal rules governing internal space. After tracing the evolution of standards in both countries from public health legislation in the late 19th century to specific building and urban codes in Italy today, and a range of standards applied to some social housing in England, it outlines the space characteristics of homes in the two countries, before drawing on a series on interviews with key built environment professionals in the cities of Turin and Manchester, to unpack the ‘conditions’ of space standard regulation in both countries. The purpose of the study has been to explore the politics, practicalities, acceptability and impact of internal space regulation in Italy and England, and to ask why regulatory standards in Italy seem more palatable than they are in England and Wales: the only remaining part of the EU where legal minimum space standard for residential development remain absent. Discussion also centres on how regulatory approaches to delivering housing quality compare with approaches based on local negotiation through planning, and how these are situated in the context of different market drivers, lending and planning cultures. Moving to a regulatory approach in England (with fixed space standards) may be problematic given that such a move would not address the market fundamentals – speculative production and investment consumption – that, alongside land supply constraints, determine the amount of space in homes. In this context, a more effective strategy might be to expose home buyers to more information on internal space, thus influencing market behaviour and thereafter, the types of homes built to supply future demand.  相似文献   
42.
The use of adult stem/progenitor cells is a challenge in current research about kidney functional regeneration. In this framework, material‐induced stem cell differentiation can become a new paradigm to promote advances in therapies. Here, the effects of both isotropic and anisotropic fibrous topographies on the podocyte differentiation of adult renal stem cells (RSCs) from human donors are investigated. The proliferation rate of RSCs is analyzed, immunofluorescence and genetic analyses of specific podocyte markers (Wilms’ tumor 1 gene, nephrin, and podocin) are performed to assess the differentiation level on the scaffolds. The studied markers are over‐expressed in RSCs cultured on aligned fibers compared to cells cultured on either protein‐functionalized films or randomly oriented fibers. In addition, RSCs cultured on aligned fibers are found to differentiate toward podocyte precursors even in basal medium conditions, thus highlighting scaffold‐induced commitment without exogenous chemicals or cellular reprogramming. Aligned polymer fiber scaffolds which provide instructive cues for RSC differentiation might lead to new biomimetic systems for renal stem cell engineering.
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43.
A response surface model was developed to describe the effects of temperature (35 to 55 degrees C), pH (3.5 to 5.5), and water activity (a(w), 0.960 to 0.992) on germination of Alicyclobacillus acidoterrestris spores. Germination and growth or viability loss depended, to varying extents, on the interactions among the independent variables and the complexity of the medium. In particular, maximum growth was achieved at temperatures between 35 and 42 degrees C and at pH values from 3.5 to 4.5. The model was validated against data not used in its development. Bias factors of 0.999 and 0.817 for 2- and 7-day models, respectively, were obtained, indicating that the models were "fail safe." Results indicated that the model provided reliable predictions of growth of A. acidoterrestris spores.  相似文献   
44.
Hepatocyte growth factor/scatter factor (HGF/SF) stimulates the invasive growth of epithelial cells via the c-MET oncogene-encoded receptor. In normal lung, both the receptor and the ligand are detected, and the latter is known to be a mitogenic and a motogenic factor for both cultured bronchial epithelial cells and non-small-cell carcinoma lines. Here, ligand and receptor expression was examined in 42 samples of primary human non-small-cell lung carcinoma of different histotype. Each carcinoma sample was compared with adjacent normal lung tissue. The Met/HGF receptor was found to be 2 to 10-fold increased in 25% of carcinoma samples (P = 0.0113). The ligand, HGF/SF, was found to be 10 to 100-fold overexpressed in carcinoma samples (P < 0.0001). Notably, while HGF/SF was occasionally detectable and found exclusively as a single-chain inactive precursor in normal tissues, it was constantly in the biologically-active heterodimeric form in carcinomas. Immunohistochemical staining showed homogeneous expression of both the receptor and the ligand in carcinoma samples, whereas staining was barely detectable in their normal counterparts. These data show that HGF/SF is overexpressed and consistently activated in non-small-cell lung carcinomas and may contribute to the invasive growth of lung cancer.  相似文献   
45.
Previous work has shown that the Tat protein of Human Immunodeficiency Virus (HIV)-1 is released by acutely infected cells in a biologically active form and enters dendritic cells upon the binding of its arginine-glycine-aspartic acid (RGD) domain to the α5β1, αvβ3, and αvβ5 integrins. The up-regulation/activation of these integrins occurs in endothelial cells exposed to inflammatory cytokines that are increased in HIV-infected individuals, leading to endothelial cell dysfunction. Here, we show that inflammatory cytokine-activated endothelial cells selectively bind and rapidly take up nano-micromolar concentrations of Tat, as determined by flow cytometry. Protein oxidation and low temperatures reduce Tat entry, suggesting a conformation- and energy-dependent process. Consistently, Tat entry is competed out by RGD-Tat peptides or integrin natural ligands, and it is blocked by anti-α5β1, -αvβ3, and -αvβ5 antibodies. Moreover, modelling–docking calculations identify a low-energy Tat-αvβ3 integrin complex in which Tat makes contacts with both the αv and β3 chains. It is noteworthy that internalized Tat induces HIV replication in inflammatory cytokine-treated, but not untreated, endothelial cells. Thus, endothelial cell dysfunction driven by inflammatory cytokines renders the vascular system a target of Tat, which makes endothelial cells permissive to HIV replication, adding a further layer of complexity to functionally cure and/or eradicate HIV infection.  相似文献   
46.
47.
In this study biomimetic poly(glycerol sebacate) PGS matrix was developed for cardiac patch application. The rationale was that such matrices would provide conducive environment for the seeded cells at the interphase with PGS. From the microstructural standpoint, PGS was fabricated into dense films and porous PGS scaffolds. From the biological aspect, biomimetic PGS membranes were developed via covalently binding peptides Tyr-Ile-Gly-Ser-Arg (YIGSR) and Gly-Arg-Gly-Asp-Ser-Pro (GRGDSP), corresponding to the epitope sequences of laminin and fibronectin, respectively onto the surface. To improve and enhance homogenous binding of peptides onto the PGS surface, chemical modification of its surface was carried out. A sequential regime of alkaline hydrolysis with 0.01 M NaOH for 5 min and acidification with 0.01 M HCl for 25 s was optimal. More COOH chemical group was exposed without causing deleterious effect on the bulk properties of the polymer as revealed by the physicochemical analysis carried out. HPLC analysis, chemical imaging and ToF-SIMS were able to establish the successful homogenous functionalization of PGS membranes with the peptides. Finally, the developed biomimetic membranes supported the adhesion and growth of rat and human cardiac progenitor cells.  相似文献   
48.
A trace coding is an injective morphism between two trace monoids. This definition naturally extends the classical notion of word coding between two free monoids. We prove that any lifting of a trace coding is a word coding. More precisely, given a trace codingF, let us choose for any lettera, a representative wordf(a) of the traceF(a). Then, the word morphismfis also a coding. This result positively solves a problem proposed by Ochmański.  相似文献   
49.
The aim of the present study was to analyze the developmental changes in three spatial processes, namely, in positional reconstruction involving the retention of spatial locations per se (Positional encoding task), in the assignment of objects to positions (Object-to-position assignment task), and in the integration of these two (Combined task). A span procedure was used to assess the development of spatial memory in children aged 6, 8, and 10 years tested in these three tasks. The findings of the present study provide developmental spans for each relocation task. Results show an age-dependent improvement in all tasks, suggesting that spatial position is not automatically encoded. The results also show different developmental patterns for the relocation tasks considered, suggesting that spatial memory comprises a number of different component processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
This study was designed to investigate the individual or combined effects of ethanol (4–12%), glucose (10–30%) and acetic acid (0–6%) on survival of planktonic and sessile cells of one strain belonging to the new species Acetobacter cerevisiae isolated from traditional balsamic vinegar. The results confirm that the planktonic cells’ survival was negatively affected by ethanol and by acetic acid; moreover, there was a positive correlation between survival and glucose concentration. On the contrary, biofilm formation was observed only in the absence of acetic acid, which was the most affecting variable on the natural ability of cells to attach and grow on surfaces. The obtained results supply new information about the physiology of a novel Acetobacter species and about its natural capability to develop biofilms so that improved control over balsamic vinegar fermentation could be implemented in the future.  相似文献   
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