Articles de revues : « Job displacement and growth »

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Kletzer, Lori G. « Job Displacement ». Journal of Economic Perspectives 12, n^o 1 (1 février 1998) : 115–36. http://dx.doi.org/10.1257/jep.12.1.115.

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The past decade and a half has seen tremendous research growth in the area of job displacement. This paper discusses the state of knowledge on the issues and questions of job loss. The 1984-96 Displaced Worker Surveys are used to describe how the characteristics of displacement are changing to include more college educated, white collar, and nonmanufacturing workers. For many workers, the long-term earnings losses following displacement are large due to the loss of firm-specific human capital. More research is needed on the questions of the causes of job displacement and on the efficacy of employment and training programs.

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Kletzer, Lori G., et Robert W. Fairlie. « The Long-Term Costs of Job Displacement for Young Adult Workers ». ILR Review 56, n^o 4 (juillet 2003) : 682–98. http://dx.doi.org/10.1177/001979390305600408.

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Using NLSY data, the authors estimate the long-term costs of job displacement for young adults. Earnings and wage losses were large for the first three years following displacement. Compared to earnings losses found by other studies for more mature workers, however, earnings losses for these young adults were short-lived, with differences between observed and expected earnings narrowing considerably five years after job loss. At that point, the shortfall in annual earnings (relative to what would have been expected absent job loss) was 9% for men and 12.5% for women, and the shortfall in hourly wages was 21.2% for men. Young workers also apparently differ from more established workers in the composition of total earnings losses: for older workers, total losses largely represent actual, immediate earnings losses, whereas for young workers the loss of opportunities for rapid earnings growth is more important.

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Gregory, Terry, Anna Salomons et Ulrich Zierahn. « Racing With or Against the Machine ? Evidence on the Role of Trade in Europe ». Journal of the European Economic Association 20, n^o 2 (6 octobre 2021) : 869–906. http://dx.doi.org/10.1093/jeea/jvab040.

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Abstract Digital technologies displace labor from routine tasks, raising concerns that labor is racing against the machine. We develop an empirically tractable task-based framework to estimate the aggregate employment effects of routine-replacing technological change (RRTC), along with the labor and product demand channels through which this aggregate effect comes about, focusing on the role of inter-regional trade. While RRTC has indeed had strong displacement effects in Europe between 1999 and 2010, it has simultaneously created new jobs through increased product demand, resulting in net employment growth. However, the distribution of gains from technological progress matters for its job-creating potential.

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Griffith, Lucy. « Soy Domination ». Undergraduate Research Journal for the Humanities 2, n^o 1 (1 avril 2017) : 152–64. http://dx.doi.org/10.17161/1808.23867.

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Genetically modified soy has experienced enormous growth in Latin America’s Southern Cone nations since the beginning of the soy boom in the 1990s. The Southern Cone refers to the nations at the southern end of South America, typically including Argentina, Paraguay, Uruguay and Brazil. The exponential growth in the soy industry created significant problems for smallholder farmers and peasant communities in Argentina and Paraguay. The soy boom led to extensive displacement, job loss, and uncertainty among peasants and smallholder farmers. Genetically modified technology also threatens the health of surrounding communities. Agribusiness giants encouraged the growth of the soy industry in Argentina and Paraguay, creating an export-based economy reliant upon raw material output. This research explores the various impacts of the genetically modified soy industry, with particular emphasis on smallholder farmers and peasants in the region.

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Slootweg, M. C., C. M. Hoogerbrugge, T. L. de Poorter, S. A. Duursma et S. C. van Buul-Offers. « The presence of classical insulin-like growth factor (IGF) type-I and -II receptors on mouse osteoblasts : autocrine/paracrine growth effect of IGFs ? » Journal of Endocrinology 125, n^o 2 (mai 1990) : 271–77. http://dx.doi.org/10.1677/joe.0.1250271.

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ABSTRACT Specific binding to and proliferative actions of insulinlike growth factors-I and -II (IGF-I and -II) on fetal mouse osteoblasts were tested. Membranes of mouse osteoblasts were shown by binding competition studies to possess specific binding sites for IGF-I and IGF-II. When IGF-I was used as a tracer, half-maximal displacement was obtained with 1·11 μg IGF-I/1 and with 14 μg IGF-II/1. Displacement of 125I-labelled IGF-I was accomplished with 2·33 μg IGF-II/1 and with 55 μg IGF-I/1. Affinity cross-linking showed bands of 130 kDa 125I-labelled IGF-I and 260 kDa 125I-labelled IGF-II under reducing conditions, further indicating the presence of classical type-I and -II receptor sites on mouse osteoblasts. Mitogenic effects of IGFs were weak; a combination with epidermal growth factor or fibroblast growth factor showed strong synergistic action however. The possibility of autocrine/paracrine actions of IGFs is discussed. Journal of Endocrinology (1990) 125, 271-277

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Boston, Amanda T. « Manufacturing Distress : Race, Redevelopment, and the EB-5 Program in Central Brooklyn ». Critical Sociology 47, n^o 6 (16 février 2021) : 961–76. http://dx.doi.org/10.1177/0896920520986614.

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Gentrification’s racial consequences are garnering increased attention as the process advances into majority–minority urban neighborhoods. This study examines the EB-5 Immigrant Investor Program’s implementation in Brooklyn, New York to ground these trends in policies through which gentrification is promoted, histories of racism and uneven development against which they are unfolding, and their disparate impacts on Black communities. While the program purports to use foreign investment to promote job growth in high unemployment areas, its financing of multimillion and billion-dollar development projects facilitates the displacement of longtime residents of the very places the initiative was designed to improve. Central Brooklyn and its outlying areas, home to one of the largest contiguous Black communities in the United States, are host to numerous EB-5 projects that have failed to produce sustainable job growth for existing residents and heightened the growing crisis of unaffordability. My analysis shows how EB-5 projects have enabled investors to use distressed areas disproportionately inhabited by poor and working-class Black communities to qualify for funding, while redistributing benefits upward to wealthy developers and affluent residents and consumers. Ultimately, the EB-5 program and other neoliberal, colorblind urban development policies exacerbate existing racial inequalities in the organization and operation of urban space.

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Howland, Marie, et George E. Peterson. « Labor Market Conditions and the Reemployment of Displaced Workers ». ILR Review 42, n^o 1 (octobre 1988) : 109–22. http://dx.doi.org/10.1177/001979398804200109.

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The authors of this study use data from the January 1984 Current Population Survey to examine the impact of local labor market conditions on the financial losses of displaced manufacturing workers. They find that strong overall growth in the local economy reduced the economic losses of white-collar workers whose industry of displacement was declining, but not of blue-collar workers in the same situation. Most older, poorly educated blue-collar workers with long tenure at their pre-layoff job suffered large financial losses even when displaced in a growing local economy. All workers, including those who were young and well-educated, suffered large financial losses when located in a depressed local economy.

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Pavelić, K., D. Vrbanec, S. Marušić, S. Levanat et T. Čabrijan. « Autocrine tumour growth regulation by somatomedin C : an in-vitro model ». Journal of Endocrinology 109, n^o 2 (mai 1986) : 233–38. http://dx.doi.org/10.1677/joe.0.1090233.

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ABSTRACT A human primary haemangiosarcoma was derived from a patient with severe hypoglycaemia. Cell line established from that tumour secreted somatomedin C in serum-free culture media. Immunoreactive somatomedin from the media eluted from Sephacryl S-200 in two peaks of 160 000 and 8000 molecular weights. Similar results were obtained when medium was acidified and chromatographed on Sephadex G-50. Binding of tracer concentrations of 125I-labelled somatomedin C to human haemangiosarcoma cells was much higher than that of 125I-labelled insulin. Half-maximal displacement of 125I-labelled somatomedin C binding occurred at an unlabelled somatomedin C concentration of 0·7 nmol/l. Insulin competed with 125I-labelled somatomedin for binding to this receptor, but 150-fold more insulin was required for half-maximal displacement. Somatomedin secreted by human haemangiosarcoma cells and purified from serum-free media strongly stimulated [methyl-3H]thymidine incorporation into the DNA of these cells. Inhibition of somatomedin C secretion by cortisol resulted in the inhibition of tumour cell proliferation but stimulation of somatomedin secretion by human GH stimulated the cell proliferation rate. It appears that production of somatomedin C in human haemangiosarcoma cells plays a part in the regulation of tumour growth by an autocrine mechanism. J. Endocr. (1986) 109, 233–238

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Bentham, J., C. Ohlsson, A. Lindahl, O. Isaksson et A. Nilsson. « A double-staining technique for detection of growth hormone and insulin-like growth factor-I binding to rat tibial epiphyseal chondrocytes ». Journal of Endocrinology 137, n^o 3 (juin 1993) : 361—NP. http://dx.doi.org/10.1677/joe.0.1370361.

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ABSTRACT In the present study a double-staining technique was developed to investigate simultaneous GH and insulin-like growth factor-I (IGF-I) binding to chondrocytes in a monolayer cell culture. Rat tibial epiphyseal chondrocytes were isolated by enzymatic digestion and cultured in monolayer. GH and IGF-I were labelled with biotin. The affinity of the biotin-labelled ligands was compared with unlabelled ligands in a radioreceptor assay. To study the distribution of GH and IGF-I binding in the monolayer, chondrocytes were incubated with biotinylated ligands with or without an excess of unlabelled ligands, followed by incubation with Vectastain ABC complex, which was then reacted with diaminobenzidine (DAB). Double staining was accomplished by carrying out the first reaction with DAB in the presence of nickel ammonium sulphate to give a black precipitate, followed by incubation with the second ligand, then ABC complex and finally DAB in the absence of nickel ammonium sulphate to give a brown stain. The presence of type-II collagen was demonstrated by immunohistochemistry and used as a marker for differentiated chondrocytes. Biotin-labelled GH and biotin-labelled IGF-I exhibited dose-dependent displacements of 125I-labelled GH and 125I-labelled IGF-I respectively from the chondrocytes in a radioreceptor assay. The displacement curves were identical to those of unlabelled ligands indicating that the affinity was unaltered. Binding of biotinylated GH to cells was seen throughout the culture in regions where there was little or no type-II collagen staining. IGF-I binding was predominantly localized to cells at high density; areas which also showed a high degree of staining for type-II collagen. The different locations of binding suggest that epiphyseal chondrocytes in monolayer culture comprise a heterogeneous cell population and that IGF-I and GH have different target cells. Journal of Endocrinology (1993) 137, 361–367

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Hosen, Sajjad, et Golam Shahria. « Economic Challenges of Rohingya Peoples : A study on Displacement (Rohingya) Peoples on Myanmar in Cox’s Bazar ». International Journal of Social, Political and Economic Research 7, n^o 3 (3 septembre 2020) : 415–36. http://dx.doi.org/10.46291/ijospervol7iss3pp415-436.

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Massive influx of Rohingya peoples into Bangladesh, fleeing a campaign of terror by the Myanmar military has had a profound impact on the communities of Cox’s Bazar. Some positive impacts include improvements in the provision of social services, increasing labor workforce, job placement of host community, growth in the number of small businesses and new livelihood opportunities. Though the Bangladesh Government & INGO is fulfilling all its humanitarian commitments, such as providing temporary shelter, foods and many more but it wants to begin repatriation as soon. However, there is a little probability that the refugees will be able to return to Myanmar in the short term due to political instability, security concerns and lack of interest by the Myanmar government in negotiating a deal. The research tries to find out what types of steps are useful if they are staying a long time in Bangladesh. The researcher found that Rohingya peoples want to work as a day laborer in the camp area, they want to start commerce in the camp for removing unemployment and agree that cooking is a source of earning. Highest average mean is 4.5690 express that most of the Rohingya peoples want education for seeking more opportunities.

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Clifton, Judith, Amy Glasmeier et Mia Gray. « When machines think for us : the consequences for work and place ». Cambridge Journal of Regions, Economy and Society 13, n^o 1 (mars 2020) : 3–23. http://dx.doi.org/10.1093/cjres/rsaa004.

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Abstract The relationship between technology and work, and concerns about the displacement effects of technology and the organisation of work, have a long history. The last decade has seen the proliferation of academic papers, consultancy reports and news articles about the possible effects of Artificial Intelligence (AI) on work—creating visions of both utopian and dystopian workplace futures. AI has the potential to transform the demand for labour, the nature of work and operational infrastructure by solving complex problems with high efficiency and speed. However, despite hundreds of reports and studies, AI remains an enigma, a newly emerging technology, and its rate of adoption and implications for the structure of work are still only beginning to be understood. The current anxiety about labour displacement anticipates the growth and direct use of AI. Yet, in many ways, at present AI is likely being overestimated in terms of impact. Still, an increasing body of research argues the consequences for work will be highly uneven and depend on a range of factors, including place, economic activity, business culture, education levels and gender, among others. We appraise the history and the blurry boundaries around the definitions of AI. We explore the debates around the extent of job augmentation, substitution, destruction and displacement by examining the empirical basis of claims, rather than mere projections. Explorations of corporate reactions to the prospects of AI penetration, and the role of consultancies in prodding firms to embrace the technology, represent another perspective onto our inquiry. We conclude by exploring the impacts of AI changes in the quantity and quality of labour on a range of social, geographic and governmental outcomes.

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Pirone, Dana M., Wendy F. Liu, Sami Alom Ruiz, Lin Gao, Srivatsan Raghavan, Christopher A. Lemmon, Lewis H. Romer et Christopher S. Chen. « An inhibitory role for FAK in regulating proliferation : a link between limited adhesion and RhoA-ROCK signaling ». Journal of Cell Biology 174, n^o 2 (17 juillet 2006) : 277–88. http://dx.doi.org/10.1083/jcb.200510062.

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Focal adhesion kinase (FAK) transduces cell adhesion to the extracellular matrix into proliferative signals. We show that FAK overexpression induced proliferation in endothelial cells, which are normally growth arrested by limited adhesion. Interestingly, displacement of FAK from adhesions by using a FAK−/− cell line or by expressing the C-terminal fragment FRNK also caused an escape of adhesion-regulated growth arrest, suggesting dual positive and negative roles for FAK in growth regulation. Expressing kinase-dead FAK-Y397F in FAK−/− cells prevented uncontrolled growth, demonstrating the antiproliferative function of inactive FAK. Unlike FAK overexpression–induced growth, loss of growth control in FAK−/− or FRNK-expressing cells increased RhoA activity, cytoskeletal tension, and focal adhesion formation. ROCK inhibition rescued adhesion-dependent growth control in these cells, and expression of constitutively active RhoA or ROCK dysregulated growth. These findings demonstrate the ability of FAK to suppress and promote growth, and underscore the importance of multiple mechanisms, even from one molecule, to control cell proliferation.

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Frey, R. S., M. R. Hathaway et W. R. Dayton. « Comparison of the effectiveness of various procedures for reducing or eliminating insulin-like growth factor-binding protein interference with insulin-like growth factor-I radioimmunoassays on porcine sera ». Journal of Endocrinology 140, n^o 2 (février 1994) : 229–37. http://dx.doi.org/10.1677/joe.0.1400229.

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Abstract We have examined the efficacy of various methods for reducing the interference of insulin-like growth factor-binding proteins (IGFBPs) with insulin-like growth factor-I (IGF-I) radioimmunoassays (RIAs) run on porcine sera. Acid–ethanol (AE) extraction, AE extraction followed by cryoprecipitation, glycyl–glycine (GG) extraction, GG extraction followed by Sephadex G-50 chromatography in 1 mol acetic acid/l (GG/G-50), and Sep-Pak chromatography were analysed. To provide a range of IGF-I and IGFBP levels, sera obtained from control, hypophysectomized, diabetic and somatotrophin-treated pigs were used. Recoveries of IGF-I added to sera prior to treatments other than Sep-Pak chromatography ranged from 85 to 105% and were not significantly different. In contrast, Sep-Pak chromatography gave extremely variable recoveries. 125I-Labelled IGF-I ligand blotting showed that GG extraction followed by acid G-50 chromatography was by far the most effective method of removing or inactivating IGFBPs in porcine sera. Consequently, this procedure was used as a standard against which to compare other extraction procedures. GG extraction alone removed or inactivated low molecular weight binding proteins but appeared to have little effect on IGFBP-3. AE extraction reduced the level of IGFBP-3 but had little effect on lower molecular weight binding proteins. Even though none of the tested procedures completely removed or inactivated the binding proteins, all samples yielded IGF-I displacement curves that were parallel to that obtained for IGF-I standard. Despite yielding parallel displacement curves, sera extracted by various methods gave dramatically different apparent IGF-I levels when subjected to IGF-I RIA. IGF-I RIA of GG extracted sera yielded IGF-I values that were closest to those obtained for identical serum samples subjected to glycyl-glycine extraction followed by G-50 chromatography. For sera from control, hypophysectomized, diabetic and somatotrophin-treated pigs, the relationship of the IGF-I level in GG-extracted sera to that in GG-extracted, acid G-50 chromatographed (GG/G-50) sera was √GG=1·13√GG/G-50−0·23 (r2=0·98). Consequently, GG extraction can be used to remove IGFBP interference with IGF-I RIAs of porcine sera from normal, hypophysectomized, diabetic and somatotrophin-treated animals. Journal of Endocrinology (1994) 140, 229–237

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Breier, B. H., B. W. Gallaher et P. D. Gluckman. « Radioimmunoassay for insulin-like growth factor-I : solutions to some potential problems and pitfalls ». Journal of Endocrinology 128, n^o 3 (mars 1991) : 347–57. http://dx.doi.org/10.1677/joe.0.1280347.

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ABSTRACT This report describes essential requirements for the validation of a radioimmunoassay (RIA) for insulin-like growth factor-I (IGF-I) and presents solutions to some problems and pitfalls commonly observed. The preparation of IGF-I to be used as radioligand or standard has to be selected carefully since some IGF-I preparations are contaminated with variants which demonstrate different potencies for different antisera used in the RIA. Accurate assessment of IGF-I levels in blood plasma requires an efficient extraction method for the IGF-binding proteins (IGFBPs). Extraction methods to remove the influence of IGFBPs in the RIA were compared using blood plasma of considerable differences in IGF-I/IGFBP ratios. Acidification of plasma before column chromatography on Sephadex G-75 (G75) is generally considered to be the most reliable extraction method, but it is very time-consuming. The acid–ethanol extraction (AE) of plasma is not valid in many situations. Non-parallel displacement to the IGF-I standard was observed with AE-extracted plasma samples in the RIA. In addition, a comparison of IGF-I values obtained in the RIA after AE or G75 extraction of fetal ovine plasma has shown no significant correlation. We report an extraction technique based on a modified AE extraction followed by cryo-precipitation (AEC). AEC extraction on blood plasma reduced residual IGFBPs to a level that did not interfere in the assay. Furthermore, AEC-extracted plasma samples showed parallel displacement in the RIA to highly purified preparations of authentic IGF-I. We observed high correlations, with a slope close to unity, of IGF-I values obtained in the RIA using the AEC or G75 extraction for plasma from different species including adult and fetal sheep, rat, mouse and man. The AEC extraction provides a rapid and simple alternative to G75 extraction for blood plasma from a variety of species provided that high-affinity antisera are used for the RIA. Journal of Endocrinology (1991) 128, 347–357

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Lee, C. Y., et D. M. Henricks. « Comparisons of various acidic treatments of bovine serum on insulin-like growth factor-I immunoreactivity and binding activity ». Journal of Endocrinology 127, n^o 1 (octobre 1990) : 139–48. http://dx.doi.org/10.1677/joe.0.1270139.

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ABSTRACT Untreated serum exhibited two forms of insulin-like growth factor-I (IGF-I)-binding protein complexes during gel chromatography: one of Mr 150 000 and the other of Mr 40 000–45 000. The majority of the immunoreactive IGF-I was associated with the Mr 150 000 complex. Following acid-ethanol extraction of serum, the binding activity at Mr 150 000 disappeared and a reduced binding activity appeared in the albumin size range. Acid incubation of serum was slightly less effective than acid-ethanol extraction in reducing the binding activity. Acid-ethanol-extracted or acid-incubated serum were parallel to IGF-I standard in the dose–response displacement of iodinated IGF-I. Gel filtration of serum with 1 mol acetic acid/l almost completely separated IGF-I and the binding proteins. Binding-protein fractions from gel filtration interfered with the immunoreactivity of IGF-I with its antibodies, causing a non-parallel displacement curve in the radioimmunoassay (RIA). Serum IGF-I could be isolated as a single peak by high performance C18 reverse-phase liquid chromatography (HPLC). The concentrations of IGF-I measured in bovine sera by RIA were similar between acid gel filtration and HPLC; the concentrations by acid-ethanol extraction and acid incubation being about 30% smaller than those measured with former methods. The lower concentration of IGF-I measured in bovine serum with acid-ethanol extraction or acid incubation appears to be due to interference of IGF-binding proteins not removed by either treatment. Journal of Endocrinology (1990) 127, 139–148

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Rafferty, K. L., S. W. Herring et F. Artese. « Three-dimensional loading and growth of the zygomatic arch ». Journal of Experimental Biology 203, n^o 14 (15 juillet 2000) : 2093–104. http://dx.doi.org/10.1242/jeb.203.14.2093.

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Despite a number of previous biomechanical studies on the zygomatic arch, unanswered questions remain about its three-dimensional loading and growth. Using young miniature swine, we have for the first time recorded strains from both the medial and lateral aspects of the squamosal bone during mastication and masseter muscle stimulation. Strains from the zygomatic bone flange and zygomatic arch growth data were also obtained from the same animals. A second study on a younger group of animals examined the growth of the zygomatic flange following partial removal of the masseter. Strain data indicated that the squamosal bone is bent out-of-plane and that this pattern of loading is quite different from that of the adjacent zygomatic bone, which experiences much lower strains with little evidence of out-of-plane bending. Surprisingly, strains were higher in the zygomatic flange during contralateral chews and contralateral masseter stimulations than during ipsilateral chews/stimulations. These strains proved to arise from movement of the condyle, explaining why partial removal of the masseter had little effect on the growth of the flange. Other growth results indicated an approximately threefold greater rate of subperiosteal deposition on the lateral surface of the squamosal bone than on the zygomatic bone. This difference in growth rate is attributed to the presence of sutures that contribute to the lateral displacement of the zygomatic bone but not the squamosal bone. This explanation does not exclude the possibility that the rapid apposition on the lateral squamosal surface is regulated by the high surface strains that result from out-of-plane bending.

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Nilsson, A., A. Lindahl, S. Edén et O. G. P. Isaksson. « Demonstration of growth hormone receptors in cultured rat epiphyseal chondrocytes by specific binding of growth hormone and immunohistochemistry ». Journal of Endocrinology 122, n^o 1 (juillet 1989) : 69—NP. http://dx.doi.org/10.1677/joe.0.1220069.

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ABSTRACT Growth hormone has been reported to exert direct effects on rat and rabbit epiphyseal chondrocytes in vitro, indicating that GH interacts with specific receptors on these cells. To investigate this possibility, binding of GH to cultured rat epiphyseal chondrocytes was studied under various experimental conditions. Chondrocytes were isolated enzymatically from epiphyseal growth plates of the proximal tibia of 20-day-old male rats and were cultured in monolayer in Ham's F-12 medium supplemented with 10% calf serum and 1% of a serum substitute. The cells were seeded at various densities (25 000–200 000 cells/well) and cultured for 5–16 days. Twenty-four hours before binding experiments, the medium containing calf serum was changed for one containing serum obtained from hypophysectomized rats, in order to avoid binding of GH present in the calf serum. Binding was studied by incubating 125I-labelled human GH (hGH) with the cells in the presence or absence of various concentrations of unlabelled hGH, bovine GH (bGH), rat GH (rGH) and ovine prolactin (oPRL). Specific binding could be demonstrated in cells cultured for 5–16 days. Binding was dependent upon time and temperature, and maximal binding was obtained by incubating the labelled hormone for 4–6 h at 24 °C. An increase in binding was noted between 7 and 12 days in culture. In cells cultured for 12 days, addition of unlabelled hGH, bGH or rGH caused a dose-dependent displacement of 125I-labelled hGH, whereas oPRL was ineffective. Scatchard analysis resulted in a linear plot, and the number of binding sites/cell was approximately 5700, with a dissociation constant of 0·46 nmol/l. The increase in binding between days 7 and 12 was independent of the density of seeded cells, but total binding was higher if the cells were seeded at a low density. By using a monoclonal antibody to the rabbit GH receptor, specific staining could be demonstrated immunohistochemically in the cultured cells. The results show the presence of GH receptors in cultured rat epiphyseal chondrocytes and also show that the culture conditions influence the expression of GH receptors. Journal of Endocrinology (1989) 122, 69–77

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Sechler, Jan L., Hongwei Rao, Anne Marie Cumiskey, Irbert Vega-Colón, Michael S. Smith, Takatoshi Murata et Jean E. Schwarzbauer. « A novel fibronectin binding site required for fibronectin fibril growth during matrix assembly ». Journal of Cell Biology 154, n^o 5 (3 septembre 2001) : 1081–88. http://dx.doi.org/10.1083/jcb.200102034.

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Fibronectin (FN) assembly into a fibrillar extracellular matrix is a stepwise process requiring participation from multiple FN domains. Fibril formation is regulated in part by segments within the first seven type III repeats (III1–7). To define the specific function(s) of this region, recombinant FNs (recFNs) containing an overlapping set of deletions were tested for the ability to assemble into fibrils. Surprisingly, recFN lacking type III repeat III1 (FNΔIII1), which contains a cryptic FN binding site and has been suggested to be essential for fibril assembly, formed a matrix identical in all respects to a native FN matrix. Similarly, displacement of the cell binding domain in repeats III9–10 to a position close to the NH2-terminal assembly domain, as well as a large deletion spanning repeats III4–7, had no effect on assembly. In contrast, two deletions that included repeat III2, ΔIII1–2 and ΔIII2–5, caused significant reductions in fibril elongation, although binding of FN to the cell surface and initiation of assembly still proceeded. Using individual repeats in binding assays, we show that III2 but not III1 contains an FN binding site. Thus, these results pinpoint repeat III2 as an important module for FN–FN interactions during fibril growth.

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Jansen, J., S. C. van Buul-Offers, C. M. Hoogerbrugge, T. L. de Poorter, M. T. Corvol et J. L. Van den Brande. « Characterization of specific insulin-like growth factor (IGF)-I and IGF-II receptors on cultured rabbit articular chondrocyte membranes ». Journal of Endocrinology 120, n^o 2 (février 1989) : 245–49. http://dx.doi.org/10.1677/joe.0.1200245.

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ABSTRACT The interaction of insulin-like growth factor (IGF)-I and IGF-II with specific type-I and -II receptor sites on rabbit articular chondrocyte membranes was studied. With labelled IGF-I as tracer, half-maximal displacement of the label was obtained with 1·4 ng IGF-I/ml and 22 ng IGF-II/ml. Using IGF-II as labelled peptide, 16 ng unlabelled IGF-II/ml and 200 ng IGF-I/ml were needed to inhibit the binding by 50%. Covalent cross-linking experiments revealed the presence of typical type-I (Mr 130 000 under reducing conditions) and type-II (Mr 260 000) receptor sites. In addition, with 125I-labelled IGF-II a very intense labelled band appeared at Mr > 300 000. This band was not found in mouse liver membranes and human placental membranes. Journal of Endocrinology (1989) 120, 245–249

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Kerr, D. E., B. Laarveld et J. G. Manns. « Effects of passive immunization of growing guinea-pigs with an insulin-like growth factor-I monoclonal antibody ». Journal of Endocrinology 124, n^o 3 (mars 1990) : 403–15. http://dx.doi.org/10.1677/joe.0.1240403.

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ABSTRACT The physiological importance of circulating as opposed to locally produced insulin-like growth factor-I (IGF-I) has not been determined. By using a passive immunoneutralization technique, our objectives were to evaluate the role of circulating IGF-I in the regulation of animal growth and pituitary GH content. A monoclonal antibody (MAb) to IGF-I, generated in our laboratory, has an affinity (Ka) of 0·13 litres/pmol for recombinant human IGF-I (rhIGF-I). Cross-reactivities of recombinant des-tripeptide IGF-I and recombinant bovine IGF-II were approximately 40 and 8% respectively. This MAb inhibited binding of purified hIGF-I to human placental membranes. In a radioimmunoassay based on displacement of 125I-labelled rhIGF-I from the MAb, displacement curves generated with dilutions of acid–gel chromatography extracts of guinea-pig serum and rhIGF-I standards were parallel. Twenty-four, 3-week-old male guinea-pigs were treated with the IGF-I MAb, a bovine herpes virus-I (BHV-I) MAb (control MAb) or vehicle (phosphate-buffered saline) (n = 8 per group). Treatments were administered i.p. every 3 days for 24 days at a dose of 20 mg/kg body weight. Blood was obtained on day 23 (48 h after treatment) and on day 25 (24 h after treatment). In a liquid-phase assay, serum from the IGF-I MAb-treated group bound 38 ± 8% (mean ± s.e.m.) (day 23) and 56 ± 7% (day 25) of an 125I-labelled rhIGF-I trace at a final dilution of 1:10 000. Because of the development of an anti-mouse immune response in the guinea-pigs, these parameters would probably have been much greater during the first 2 weeks of the trial. Of the total IGF-I in serum, 50 ± 5% and 61±4% could be immunoprecipitated with an excess of rabbit anti-mouse immunoglobulin in samples from days 23 and 25 respectively. Comparisons between the groups treated with IGF-I MAb and BHV-I MAb revealed no significant differences in whole animal growth rate, growth of individual tissues, or pituitary GH content. Mean serum concentrations of IGF-I were 69 and 99% greater in IGF-I MAb-treated group than in the BHV-I MAb-treated group on days 23 and 25 respectively. These differences probably resulted from an extension of the half-life of IGF-I in serum of animals treated with the IGF-I MAb. The lack of effect of treatment with the IGF-I MAb suggests that local production of IGF-I is generally sufficient to maintain normal growth or that local production or activity of IGF-I is increased in a compensatory fashion. Journal of Endocrinology (1990) 124, 403–415

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Jaffrain-Rea, ML, E. Petrangeli, C. Lubrano, G. Minniti, D. Di Stefano, F. Sciarra, L. Frati, G. Tamburrano, G. Cantore et A. Gulino. « Epidermal growth factor binding sites in human pituitary macroadenomas ». Journal of Endocrinology 158, n^o 3 (1 septembre 1998) : 425–33. http://dx.doi.org/10.1677/joe.0.1580425.

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The number of epidermal growth factor (EGF) binding sites was determined by competitive binding assays in a series of 46 pituitary macroadenomas. A single concentration of 125I-EGF (1 nM) was used for all experiments. In four cases, a displacement curve was obtained by adding increasing concentrations of cold EGF, and Scatchard analysis showed the presence of two classes of EGF binding sites, with Kd1 = 0.62 +/- 0.23 nM and Kd2 = 53.8 +/- 8.2 nM for the high- and low-affinity binding sites respectively. The distribution of EGF binding sites was studied in 42 cases by a single-point assay, in the presence and in the absence of a 100-fold cold EGF excess. A non-parametric distribution of EGF binding sites was observed (median 10.2 fmol/mg membrane protein, range 0.0-332.0). EGF-receptor positivity, defined as EGF binding > or = 10.0 fmol/mg protein, was observed in 23 samples (54.8%), especially in prolactinomas (76.5%, P < 0.05 vs other tumors taken together) and in gonadotrope adenomas (62.5%). EGF binding was higher in invasive than in non-invasive adenomas (median: 12.8 vs 0.0 fmol/mg membrane protein, P = 0.047), and especially in adenomas invading the sphenoid sinus (median 26.7 fmol/mg membrane protein, P = 0.008 vs other adenomas). EGF binding also tended to increase with the grade of supra/extrasellar extension according to Wilson (P = 0.15). Sex steroid receptors (SSRs) were simultaneously determined in both cytosolic and nuclear fractions of 31 pituitary adenomas. Estrogen and progesterone receptors were determined by an enzyme-linked immunoassay and androgen receptors by a competitive binding assay with [3H]methyltrienolone. No correlation could be found between EGF binding and either the gender and gonadal status of the patients, or the expression of SSRs by the adenomas. We conclude that the EGF family of growth factors may play a role in the evolution of a significant subset of human pituitary adenomas, especially in their invasiveness, and that a high EGF binding capacity may represent an additional marker of aggressiveness for these tumors. Sex steroids do not appear to have a significant role in the regulation of EGF binding in vivo in these tumors.

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Wang, J. F., L. J. Fraher et D. J. Hill. « Characterization of insulin-like growth factor-binding protein in ovine amniotic fluid ». Journal of Endocrinology 127, n^o 2 (novembre 1990) : 325–33. http://dx.doi.org/10.1677/joe.0.1270325.

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ABSTRACT We have characterized an insulin-like growth factor (IGF)-binding protein present in ovine amniotic fluid. Using an activated charcoal-binding assay, whole amniotic fluid specifically bound approximately 20–30% of 125I-labelled human (h) IGF-II added, while the binding of 125I-labelled hIGF-I was minimal. Radioimmunoassay for IGF-I or -II in ovine biological fluids showed that values in amniotic fluid were 9- to 13-fold less than in fetal plasma, while gel filtration of amniotic fluid on Sephadex G-50 eluted with 1 mol acetic acid/l revealed no additional binding activity which had been complexed to IGFs at neutral pH. Together, these observations suggest that the binding activity in amniotic fluid is largely unsaturated. Competition studies for the displacement of 125I-labelled IGF-II binding to amniotic fluid by increasing amounts of unlabelled IGF-I or -II, using the charcoal assay, showed that IGF-II was 30-fold more potent than IGF-I. Scatchard analysis revealed a single class of binding site for IGF-II, with a binding affinity of 0·68 ±0·18 litres/nmol (mean ± s.d., n = 3). Ligand blot analysis of amniotic fluid by separation on 8% SDS-PAGE, transfer to nitrocellulose membranes, incubation with 125I-labelled IGF-II and autoradiography revealed a single band of IGF-binding protein with approximate molecular size of 38 kDa. Additional IGF-binding species of 20, 28, 48 and > 180 kDa were present in ovine fetal plasma. Separation of amniotic fluid on Concanavalin A–Sepharose revealed that it had little carbohydrate content. These results show that ovine amniotic fluid contains an unsaturated, non-glycosylated IGF-binding protein with high affinity for IGF-II. These characteristics differ from those of the IGF-binding proteins purified from human amniotic fluid. Journal of Endocrinology (1990) 127, 325–333

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Crawford, B. A., J. L. Martin, C. J. Howe, D. J. Handelsman et R. C. Baxter. « Comparison of extraction methods for insulin-like growth factor-I in rat serum ». Journal of Endocrinology 134, n^o 2 (août 1992) : 169–76. http://dx.doi.org/10.1677/joe.0.1340169.

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ABSTRACT This study was undertaken to compare various extraction methods for insulin-like growth factor-binding proteins (IGFBPs) from insulin-like growth factor-I (IGF-I) in rat serum systematically, before measurement of IGF-I by radioimmunoassay (RIA). The values obtained in the IGF-I RIA following acid–ethanol (AE), acid-ethanol cryoprecipitation (AEC) and formic acid-acetone (FA) extraction methods were compared with the IGF-I values obtained following high-performance liquid chromatography (HPLC), which was the reference method. Radio-ligand blots were used to determine the pattern and degree of IGFBP removal by these methods. Over a wide range of circulating IGF-I levels, AE and AEC extraction gave IGF-I levels comparable with those obtained following HPLC. FA extraction resulted in IGF-I levels that were consistently higher (P <0·01) than those obtained following HPLC and gave non-parallel displacement curves in comparison with recombinant IGF-I standards (P <0·01). Ligand blots demonstrated a similar pattern of IGFBP removal among the three methods with almost complete removal of IGFBP-3 but only 30–40% removal of the lower molecular weight IGFBPs. These lower molecular weight IGFBPs did not interfere with the RIA measurements of IGF-I from AE and AEC extracts. Therefore the AE extraction method of Daughaday, originally validated for use in human serum, is also satisfactory for use in rat serum. The complete removal of IGF-binding activity does not appear essential for accurate measurement of IGF-I by RIA, although this may depend on the specific binding characteristics of the IGF-I antiserum. Journal of Endocrinology (1992) 134, 169–176

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Bramley, T. A., et G. S. Menzies. « Specific binding sites for 125I-labelled epidermal growth factor in the ovine corpus luteum and human placenta ». Journal of Endocrinology 135, n^o 1 (octobre 1992) : 5–16. http://dx.doi.org/10.1677/joe.0.1350005.

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ABSTRACT Specific, high-affinity binding sites for radiolabelled mouse epidermal growth factor (mEGF) were demonstrated in homogenates and membranes of ovine corpora lutea. Subcellular fractionation on sucrose density gradients demonstrated that luteal EGF receptors were associated with fractions enriched in cell surface-membrane markers. Binding of 125I-labelled mEGF to ovine luteal EGF receptors was dependent on the pH, temperature and duration of incubation, and on the concentration of metal ions present in the incubation medium. Unlabelled mEGF and human EGF (urogastrone) competed for the binding of radiolabelled mEGF to ovine luteal homogenates at low doses (half-maximal inhibition of binding (IC50) at 2–3 nmol/l). Transforming growth factor-α also competed for mEGF-binding sites (IC50, 4–10 nmol/l), but a range of peptides, growth factors and protein hormones were ineffective at much higher concentrations. Concave Scatchard plots for 125I-labelled EGF binding and Hill coefficients of <1 for displacement radiolabelled EGF suggested negative co-operativity of binding sites, and dilution at equilibrium accelerated the rate of dissociation of 125I-labelled EGF from human placental (but not from ovine luteal) receptors. Specific EGF-binding sites were also demonstrated in rat and rabbit placental homogenates, and in luteal homogenates of the pig. Luteal concentrations of EGF receptors appeared to be reduced significantly during early pregnancy in both the pig and sheep. Journal of Endocrinology (1992) 135, 5–16

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Fujinaga, H., M. Yamoto, T. Shikone et R. Nakano. « FSH and LH up-regulate epidermal growth factor receptors in rat granulosa cells ». Journal of Endocrinology 140, n^o 2 (février 1994) : 171–77. http://dx.doi.org/10.1677/joe.0.1400171.

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Abstract Epidermal growth factor (EGF) modulates ovarian folliculogenesis and steroidogenesis and its binding sites have been demonstrated in the ovary. We investigated the localization of EGF-binding sites in the rat ovary, and the effects of FSH and LH on EGF binding to cultured granulosa cells. Autoradiographic localization of 125I-labelled mouse EGF-binding sites was demonstrated in the granulosa and luteal cells. Displacement study and Scatchard analysis showed that a single class of specific binding sites for 125I-labelled mouse EGF was present in the granulosa cells, obtained from the ovaries of immature rats treated with diethylstilboesterol. The number of binding sites and the apparent dissociation constant were 4336 binding sites/cell and 3·42 pmol/l respectively. The granulosa cells were cultured for 48 h at 37 °C in medium alone or with increasing amounts of ovine FSH (oFSH; 1–1000 μg/l). FSH treatment increased 125I-labelled mouse EGF binding to the granulosa cells in a dose-dependent manner. After culture with oFSH (100 μg/l) for 48 h, the cells were cultured in medium alone or with increasing amounts of ovine LH (oLH; 1–1000 μg/l) for an additional 48 h. LH treatment also increased 125I-labelled mouse EGF binding in a dose-dependent manner, compared with the control. However, neither FSH nor LH altered receptor-binding affinity. Furthermore, after culture with oFSH (FSH-primed) or oFSH followed by oLH (LH-primed), tissue plasminogen activator (tPA) activities in the conditioned media were examined by fibrin autography. FSH-primed or LH-primed granulosa cells were more responsive to EGF action to induce an increase in tPA activity. In conclusion, it is suggested that functional receptors for EGF in rat granulosa cells are up-regulated by FSH and LH. Journal of Endocrinology (1994) 140, 171–177

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Bryson, J. M., et R. C. Baxter. « High-affinity receptor for insulin-like growth factor II in rat liver : properties and regulation in vivo ». Journal of Endocrinology 113, n^o 1 (avril 1987) : 27–35. http://dx.doi.org/10.1677/joe.0.1130027.

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ABSTRACT Receptors for insulin-like growth factor II (IGF-II) have been identified in many tissue types and have been shown to differ widely in their specificities and affinities. We have characterized the IGF-II receptor in rat liver microsomal membranes, both in the intact membrane and in a solubilized extract. Binding was time- and temperature-dependent and was unaffected by changes in pH in the range 6–9. Half-maximal displacement was obtained with 0·33 ng IGF-II/ml standard, and Scatchard analysis showed a class of receptors with an affinity for IGF-II of 1·33 ± 0·36 × 1010 litres/mol which increased threefold in the presence of Ca (1 mmol/l) to 3·74 ± 0·89 × 1010 litres/mol. There was also a threefold decrease in the rate of dissociation in the presence of Ca. Cross-reactivity with IGF-I was < 1% and there was no cross-reactivity with insulin. Infusion of rat GH or prolactin for 1 week, at the rate of 175–200 μg/day, into female rats had no effect on IGF-II binding in control animals, but rat GH infusion caused a 60% increase (P< 0·001) in binding in hypophysectomized rats by increasing the number of receptors. These studies demonstrate that rat liver microsomal membranes contain a highly specific, high-affinity receptor for IGF-II which may be under partial GH control J. Endocr. (1987) 113, 27–35

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Nauen, J. C., et R. E. Shadwick. « The scaling of acceleratory aquatic locomotion : body size and tail-flip performance of the california spiny lobster panulirus interruptus ». Journal of Experimental Biology 202, n^o 22 (15 novembre 1999) : 3181–93. http://dx.doi.org/10.1242/jeb.202.22.3181.

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Tail-flipping is a crucial escape locomotion of crustaceans which has been predicted to be limited by increased body mass (M(b)). Given isometric growth, one may predict that with growth event duration will decrease as M(b)(−)(1/3), translational distances will increase as M(b)(1/3), translational velocity will be independent of M(b), translational acceleration will decrease as M(b)(−)(1/3), angular displacement will be independent of M(b) and angular velocity and angular acceleration will decrease as M(b)(−)(1/3). We tested these hypotheses by examining the scaling of 12 morphological variables, five kinematic variables and six performance variables of tail-flipping by the California spiny lobster Panulirus interruptus. Growth approximated isometry, which validated the use of the proposed scaling hypotheses. For animals from 1 to 1000 g M(b), the predicted scaling relationships for tail-flip duration and translational distance and velocity variables were supported; however, translational acceleration performance was much better than predicted. Predictions for rotation and rotational velocity variables were not supported, while the rotational acceleration data closely matched the predicted relationship. The increase in tail-flip duration as predicted suggests that muscle shortening velocity decreases with growth; the sustained acceleration performance (similar to findings for shrimp and fish fast-starts) suggests that muscle force output may increase at a greater rate than predicted by isometry. The scaling of rotational acceleration indicates that the torque produced during the tail-flip scales with a mass exponent greater than 1. Comparison of the tail-flip performance of Panulirus interruptus with those of other crustacean species reveals a wide range in performance by animals of similar body size, which suggests that the abdominal muscle may show interesting differences in contractile properties among different species.

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Jen, Ming-Hwa R., Li-Jen Hsu, Yu-Cheng Liang et Ying-Hui Wu. « The mechanical properties and fatigue responses of fiber metal nanocomposite laminates with double-edged cracks ». Journal of Mechanics 38 (2022) : 1–12. http://dx.doi.org/10.1093/jom/ufab034.

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ABSTRACT The fiber metal laminates (FMLs) of hybrid Ti/APC-2 neat and nanocomposite laminates were fabricated. Geometrically symmetric and anti-symmetric double-edged cracks were cut in FMLs. From tensile tests, we received the load vs. displacement curves, stress intensity factors of mixed mode and mechanical properties. From cyclic tests, the load vs. cycles (P–N) curves, residual life and failure mechanisms were obtained. The mechanical properties of symmetrically cracked specimens were slightly lower than those of anti-symmetrically cracked counterparts. As the crack length increases and inclination angle decreases, the fatigue life decreases. The enhancement of nanopowder improved the ultimate load and fatigue life. The local stress intensity at the crack tip dominates the fatigue responses. The piece of elliptical part was observed from cyclic tests at failure. Although the attraction of two crack tips accelerated the crack growth towards each other, the delay to failure was caused by two crack tips circling around and forming a small piece of ellipse centrally.

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Watanabe, N., R. G. Rosenfeld, R. L. Hintz, L. A. Dollar et R. L. Smith. « Characterization of a specific insulin-like growth factor-I/somatomedin-C receptor on high density, primary monolayer cultures of bovine articular chondrocytes : regulation of receptor concentration by somatomedin, insulin and growth hormone ». Journal of Endocrinology 107, n^o 2 (novembre 1985) : 275–83. http://dx.doi.org/10.1677/joe.0.1070275.

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ABSTRACT In order to obtain a phenotypically stable cell population of chondrocytes, high density primary monolayer cultures of bovine articular chondrocytes were established. Using these cultures, a specific insulin-like growth factor-I/somatomedin-C (IGF-I/SM-C) receptor was demonstrated and characterized. At 15 °C steady-state binding was attained by 5 h, and averaged 25% per 2·2 × 106 cells. Fifty per cent displacement of 125I-labelled IGF-I/SM-C by unlabelled IGF-I/SM-C occurred at concentrations of only 2·3 ng/ml, whereas IGF-II and porcine insulin were approximately 15-and 1000-fold less potent respectively. Scatchard analysis gave a linear plot, with a calculated association constant of 2·26 × 109 l/mol and a receptor number of 15 400 sites per cell. Preincubation of chondrocyte monolayers with either IGF-I/SM-C or porcine insulin at 37 °C for 20 h resulted in reduction of 125I-labelled IGF-I/SM-C binding in a dose-dependent manner, although higher concentrations were required with insulin. More than 40% down-regulation of the receptor occurred with IGF-I/SM-C at concentrations of 10 nmol/l and nearly 70% reduction at 50 nmol/l. Interestingly, after preincubation with either human (h) or bovine (b)GH, 40% down-regulation of 125I-labelled IGF-I/SM-C binding was observed at concentrations of 10 μmol/l. Local production of IGF-I/SM-C by chondrocytes in response to GH stimulation may have occurred, but, because only 120 pmol IGF-I/SM-C and < 30 pmol IGF-I/SM-C per litre were recovered from serum-free conditioned media preincubated with bGH and hGH respectively, this was not established. These studies demonstrate that cultured bovine articular chondrocytes possess a highly specific IGF-I/SM-C receptor, and that this receptor population is regulated not only by IGF-I/SM-C and insulin but also by high concentrations of either hGH or bGH. These results are consistent with the growth-promoting action of IGF-I/SM-C on skeletal tissues, and suggest the possibility that GH itself may play its own role to modulate IGF-I/SM-C receptors on chondrocytes. J. Endocr. (1985) 107, 275–283

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Chen, P., J. E. Murphy-Ullrich et A. Wells. « A role for gelsolin in actuating epidermal growth factor receptor-mediated cell motility. » Journal of Cell Biology 134, n^o 3 (1 août 1996) : 689–98. http://dx.doi.org/10.1083/jcb.134.3.689.

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Phospholipase C-gamma (PLC gamma) is required for EGF-induced motility (Chen, P., H. Xie, M.C. Sekar, K.B. Gupta, and A. Wells. J. Cell Biol. 1994. 127:847-857); however, the molecular basis of how PLC gamma modulates the actin filament network underlying cell motility remains undetermined. We propose that one connection to the actin cytoskeleton is direct hydrolysis of PIP2 with subsequent mobilization of membrane-associated actin modifying proteins. We used signaling-restricted EGFR mutants expressed in receptor-devoid NR6 fibroblast cells to investigate whether EGFR activation of PLC causes gelsolin mobilization from the cell membrane in vivo and whether this translocation facilitates cell movement. Gelsolin anti-sense oligonucleotide (20 microM) treatment of NR6 cells expressing the motogenic full-length (WT) and truncated c'1000 EGFR decreased endogenous gelsolin by 30-60%; this resulted in preferential reduction of EGF (25 nM)-induced cell movement by > 50% with little effect on the basal motility. As 14 h of EGF stimulation of cells did not increase total cell gelsolin content, we determined whether EGF induced redistribution of gelsolin from the membrane fraction. EGF treatment decreased the gelsolin mass associated with the membrane fraction in motogenic WT and c'1000 EGFR NR6 cells but not in cells expressing the fully mitogenic, but nonmotogenic c'973 EGFR. Blocking PLC activity with the pharmacologic agent U73122 (1 microM) diminished both this mobilization of gelsolin and EGF-induced motility, suggesting that gelsolin mobilization is downstream of PLC. Concomitantly observed was reorganization of submembranous actin filaments correlating directly with PLC activation and gelsolin mobilization. In vivo expression of a peptide that is reported to compete in vitro with gelsolin in binding to PIP2 dramatically increased basal cell motility in NR6 cells expressing either motogenic (WT and c'1000) or nonmotogenic (c'973) EGFR; EGF did not further augment cell motility and gelsolin mobilization. Cells expressing this peptide demonstrated actin reorganization similar to that observed in EGF-treated control cells; the peptide-induced changes were unaffected by U73122. These data suggest that much of the EGF-induced motility and cytoskeletal alterations can be reproduced by displacement of select actin-modifying proteins from a PIP2-bound state. This provides a signaling mechanism for translating cell surface receptor-mediated biochemical reactions to the cell movement machinery.

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Goldspink, G. « Malleability of the motor system : a comparative approach ». Journal of Experimental Biology 115, n^o 1 (1 mars 1985) : 375–91. http://dx.doi.org/10.1242/jeb.115.1.375.

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The various ways in which the power output of muscles can be changed are described. As a result of exercise and growth, force production is increased by an increase in the cross-sectional area of the fibres. This is associated with changes in the rate of synthesis and degradation of muscle proteins which lead to build up of the myofibrils. These then split longitudinally when they reach a critical size. This process is repeated so that the number of myofibrils increases very considerably. Also, during growth, the displacement is increased by increasing the length of the muscles. To do this more sarcomeres are produced in series along the length of the fibres. This is induced by stretch which also encourages fibre growth in girth as well as in length. Yet another way of changing the power output of a muscle is to change the types of muscle fibres (motor units) within the muscle. Fibre type transformation has been fibres (motor units) within the muscle. Fibre type transformation has been shown to occur with cross innervation and stimulation but it does not usually occur with exercise training. It has been possible, however, to change the fibre type proportions in young animals. Also, by combining stretch with stimulation, it has been possible for instance to make the fast glycolytic fibres add on fast oxidative type sarcomeres or even slow oxidation type sarcomeres. Interestingly, fibre transformation also occurs in some species of fish during acclimation to low temperatures in that the specific myofibrillar ATPase activity is increased. This means that the reduction in power output due to decreased temperature is to some extent compensated for by an increase in the intrinsic rate of shortening. EMG studies of fish swimming at different temperatures have shown that the acclimated fish can swim faster and can derive more aerobic sustainable power as a result of this change.

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Hall, Ralph P., Robert Ashford, Nicholas A. Ashford et Johan Arango-Quiroga. « Universal Basic Income and Inclusive Capitalism : Consequences for Sustainability ». Sustainability 11, n^o 16 (19 août 2019) : 4481. http://dx.doi.org/10.3390/su11164481.

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Over the past forty years, income growth for the middle and lower classes has stagnated, while the economy (and with it, economic inequality) has grown significantly. Early automation, the decline of labor unions, changes in corporate taxation, the financialization and globalization of the economy, deindustrialization in the U.S. and many OECD countries, and trade have contributed to these trends. However, the transformative roles of more recent automation and digital technologies/artificial intelligence (AI) are now considered by many as additional and potentially more potent forces undermining the ability of workers to maintain their foothold in the economy. These drivers of change are intensifying the extent to which advancing technology imbedded in increasingly productive real capital is driving productivity. To compound the problem, many solutions presented by industrialized nations to environmental problems rely on hyper-efficient technologies, which if fully implemented, could further advance the displacement of well-paid job opportunities for many. While there are numerous ways to address economic inequality, there is growing interest in using some form of universal basic income (UBI) to enhance income and provide economic stability. However, these approaches rarely consider the potential environmental impact from the likely increase in aggregate demand for goods and services or consider ways to focus this demand on more sustainable forms of consumption. Based on the premise that the problems of income distribution and environmental sustainability must be addressed in an integrated and holistic way, this paper considers how a range of approaches to financing a UBI system, and a complementary market solution based on an ownership-broadening approach to inclusive capitalism, might advance or undermine strategies to improve environmental sustainability.

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Carón, R. W., G. A. Jahn et R. P. Deis. « Lactogenic actions of different growth hormone preparations in pregnant and lactating rats ». Journal of Endocrinology 142, n^o 3 (septembre 1994) : 535–45. http://dx.doi.org/10.1677/joe.0.1420535.

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Abstract We studied the capacity of different GH preparations, natural human (h)GH, recombinant hGH (rhGH), rat (r)GH, ovine (o)GH, bovine (b)GH and porcine (p)GH, and ovine prolactin (oPRL), to stimulate lactogenesis in ovario-hysterectomized pregnant rats or intact lactating rats treated with bromocriptine (BC). Ovariohysterectomy (OVX-HYS) performed at 0800 h on day 19 of pregnancy induced lactogenesis, i.e. increases in mammary casein and lactose and positive response to the oxytocin test, 28 h later. Lactogenesis was prevented by treatment with BC (1·5 mg/kg) immediately after surgery (OVX-HYS-BC). The hormones were given at doses of 0·25 or 0·5 mg/rat (except rhGH given only at 0·5 mg/rat) at 1200 and 2000 h on day 19. Casein was increased by both doses of oPRL and hGH, rhGH and 0·25 mg oGH, and lactose by both doses of oPRL, rhGH and 0·25 mg rGH. The other GH preparations had no effect. The oxytocin test demonstrated the presence of milk in the mammary tissues of the OVX-HYS rats and in the OVX-HYS-BC plus oPRL (0·25 and 0·5 mg) or rhGH-treated groups. Injection of BC to pregnant rats at 2000 h on day 20 and at 0800 h on day 21 decreased litter growth on the first 4 days postpartum. Two-thirds of the litters resumed growth after day 4, indicating the recuperation of milk production, while the rest never recuperated. Serum prolactin in BC-treated rats was reduced until day 4 postpartum. On day 6 the rats which had recuperated had normal values, while those which had still not recuperated had lower values. BC-treated rats were injected s.c. with 0·25 mg each of oPRL, hGH, rGH, oGH, bGH or pGH, or 0·25 or 0·5 mg rhGH/rat, immediately postpartum and 12, 24 and 36 h later. hGH and 0·5 mg rhGH induced levels of milk production similar to controls except on day 3. oPRL and rhGH (0·25 mg), induced a partial reversion of the effect of BC. rGH and oGH had a slight effect on days 1 and 2 and all the litters resumed growth on day 7. In contrast, pGH and bGH were inactive. The affinity of hGH for the prolactin receptor, measured as displacement of 125I-labelled oPRL binding to crude liver membranes, was comparable with that of oPRL. While rhGH was ten times less active than oPRL, rPRL was 100 times lower and all the other GH preparations had at least 104 times lower capacity to displace 125I-labelled oPRL. These results indicate that both natural and recombinant hGHs are potent inductors of milk synthesis in pregnant or lactating rats, most probably due to their actions at the level of the prolactin receptor. rGH and oGH have a partial action, while pGH and bGH seem to be inactive. The actions of non-human GHs may be explained by their somatogenic properties exclusively, and indicate that GH may play a role in the optimization of milk production during lactation and an accessory role in the induction of lactogenesis in pregnant rats. Journal of Endocrinology (1994) 142, 535–545

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Rand-Weaver, M., P. Swanson, H. Kawauchi et W. W. Dickhoff. « Somatolactin, a novel pituitary protein : purification and plasma levels during reproductive maturation of coho salmon ». Journal of Endocrinology 133, n^o 3 (juin 1992) : 393–403. http://dx.doi.org/10.1677/joe.0.1330393.

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ABSTRACT Somatolactin (SL), a newly discovered fish pituitary protein belonging to the GH/prolactin family, was isolated from coho salmon (Oncorhynchus kisutch). Antibodies were raised to purified coho SL, and a homologous radioimmunoassay was developed and validated. The assay was specific for SL as indicated by the absence of cross-reactivity with coho salmon GH, gonadotrophins I and II and less than 0·2% cross-reaction to prolactin. Serial dilutions of plasma and pituitary extracts from Oncorhynchus species including coho salmon, chinook salmon and rainbow trout were parallel to the coho salmon SL standard curve. Displacement curves for dilutions of Atlantic salmon (Salmo salar) plasma, but not pituitary extract were parallel to the standards. Plasma levels of SL were measured in coho salmon throughout the final year of reproductive maturation. During the period of gonadal growth, plasma SL levels increased and were highly correlated to oestradiol levels in females and 11-ketotestosterone levels in males. Peak levels of SL were observed at the time of final maturation and spawning in both sexes. It is hypothesized that SL may regulate some physiological aspect of reproduction. Journal of Endocrinology (1992) 133, 393–403

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Tremblay, Gilbert. « Rehabilitation of Surgically Relocated Integrated Dental Implants With and Without Bone Morphogenesis Protein-2 ». Journal of Oral Implantology 39, n^o 4 (1 août 2013) : 409–15. http://dx.doi.org/10.1563/aaid-joi-d-13-00077.

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In the following case report, three osseointegrated implants placed in a dysfunctional and nonaesthetic position were successfully relocated with innovative surgical techniques were followed by a comprehensive dental rehabilitation. The goal of this report is to communicate the surgical techniques used to successfully relocate dental implants rather than replace them. Two techniques were used for these implants relocation. One technique consisted of displacing the integrated implant with some similarity to the alveolar distraction osteogenesis but without using the distraction device. The second surgical technique involved the displacement of the 2 adjacent implants, similarly to the first approach, except that an osseoinductive molecule, recombinant human bone morphogenetic protein-2, was used for guided bone growth. It was possible to relocate dental implants within bone blocs and rehabilitate them to adopt new dental abilities by complying with bone regeneration parameters. However, advanced treatment planning with computerized tomography scans, parametric software, and stereolithography models as well as guided surgery and bone regeneration products were used.

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Couch, K. A. « Late Life Job Displacement ». Gerontologist 38, n^o 1 (1 février 1998) : 7–17. http://dx.doi.org/10.1093/geront/38.1.7.

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Kandilov, Amy M. G., et Ivan T. Kandilov. « Job Displacement from Agriculture ». American Journal of Agricultural Economics 92, n^o 3 (13 mars 2010) : 591–607. http://dx.doi.org/10.1093/ajae/aaq021.

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Sawitzky, H., et F. Grolig. « Phragmoplast of the green alga Spirogyra is functionally distinct from the higher plant phragmoplast. » Journal of Cell Biology 130, n^o 6 (15 septembre 1995) : 1359–71. http://dx.doi.org/10.1083/jcb.130.6.1359.

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Cytokinesis in the green alga Spirogyra (Zygnemataceae) is characterized by centripetal growth of a septum, which impinges on a persistent, centrifugally expanding telophase spindle, leading to a phragmoplast-like structure of potential phylogenetic significance (Fowke, L. C., and J. D. Pickett-Heaps. 1969. J. Phycol. 5:273-281). Combining fluorescent tagging of the cytoskeleton in situ and video-enhanced differential interference contrast microscopy of live cells, the process of cytokinesis was investigated with emphasis on cytoskeletal reorganization and concomitant redistribution of organelles. Based on a sequence of cytoskeletal arrangements and the effects of cytoskeletal inhibitors thereon, cytokinetic progression could be divided into three functional stages with respect to the contribution of microfilaments (MFs) and microtubules (MTs): (1) Initiation: in early prophase, a cross wall initial was formed independently of MFs and MTs at the presumptive site of wall growth. (2) Septum ingrowth: numerous organelles accumulated at the cross wall initial concomitant with reorganization of the extensive peripheral interphase MF array into a distinct circumferential MF array. This array guided the ingrowing septum until it contacted the expanding interzonal MT array. (3) Cross wall closure: MFs at the growing edge of the septum coaligned with and extended along the interzonal MTs toward the daughter nuclei. Thus, actin-based transportation of small organelles during this third stage occurred, in part, along a scaffold previously deployed in space by MTs. Displacement of the nuclei-associated interzonal MT array by centrifugation and depolymerization of the phragmoplast-like structure showed that the success of cytokinesis at the third stage depends on the interaction of both MF and MT cytoskeletons. Important features of the phragmoplast-like structure in Spirogyra were different from the higher plant phragmoplast: in particular, MFs were responsible for the positioning of organelles at the fusion site, contrary to the proposed role of MTs in the higher plant phragmoplast.

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Crosby, S. R., C. D. Anderton, M. Westwood, J. M. P. Holly, S. C. Cwyfan Hughes, M. Gibson, C. A. Morrison, R. J. Young et A. White. « Measurement of insulin-like growth factor-II in human plasma using a specific monoclonal antibody-based two-site immunoradiometric assay ». Journal of Endocrinology 137, n^o 1 (avril 1993) : 141–50. http://dx.doi.org/10.1677/joe.0.1370141.

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ABSTRACT An immunoradiometric assay (IRMA) for the measurement of insulin-like growth factor-II (IGF-II) in human plasma has been developed, optimized and evaluated clinically in normal subjects and patients with disorders of the GH/IGF-I axis. Six monoclonal antibodies (MAbs) to recombinant human IGF-II (rhIGF-II) were produced, all of which had low cross-reactivity with rhIGF-I (< 0·01%) and insulin (< 0·01%). Compatibility of pairs of MAbs was tested in two-site IRMAs using three radioiodinated MAbs and three MAbs linked to Sephacryl S-300 (with separation of bound and free radiolabelled MAb by sucrose layering). Seven pairs of MAbs bound rhIGF-II and the combination of 125I-labelled W3D9 and W2H1 linked to solid phase was selected. The optimized assay had a completion time of 4 h, a minimum detection limit of 30 ng/ml (2·5 standard deviations from the zero standard) and detected a single peak of endogenous IGF-II in normal plasma which co-eluted with rhIGF-II after acid gel chromatography. IGF-II was measured in formic acid/acetone extracts of plasma from 16 normal subjects (mean 685, range 516–1008 μg/l), four acromegalic patients (mean 637, range 553–700 μg/l), fourteen patients with type-1 diabetes (mean 635, range 247–753 μg/l), nine patients with uraemia (mean 423, range 78–850 μg/l), and three patients with Laron-type GH insensitivity (75, 35 and 36 μg/l). No significant fluctuations were detected between samples obtained hourly from 08.00 to 19.00 h in normal subjects. Low levels of IGF-binding proteins (IGFBPs) remaining in plasma extracts may interfere with the measurement of IGF-II and give rise to falsely elevated IGF-II levels in radioimmunoassays or falsely suppressed levels in IRMAs. Such interference did not occur with the IRMA when used to measure IGF-II in extracts from normal subjects, acromegalic patients and patients with type-1 diabetes, and the addition of excess rhIGF-I in order to displace IGF-II from residual IGFBPs had no effect on IGF-II measurements in these samples. However, levels of IGF-II measured in extracts from patients with Laron-type GH insensitivity and patients with uraemia increased markedly after preincubation with excess rhIGF-I. The accurate measurement of IGF-II by IRMA in extracts from these subjects therefore requires the displacement of IGF-II from IGFBPs prior to assay. We conclude that, in contrast to radioimmunoassays, the two-site IRMA developed here provides a practical, rapid and specific method for the measurement of IGF-II in human plasma. Journal of Endocrinology (1993) 137, 141–150

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Charles, Kerwin Kofi, et Melvin Stephens, Jr. « Job Displacement, Disability, and Divorce ». Journal of Labor Economics 22, n^o 2 (avril 2004) : 489–522. http://dx.doi.org/10.1086/381258.

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Aaronson, Daniel, Sumit Agarwal, Julie L. Hotchkiss et Taylor Kelley. « Job displacement and financial outcomes ». Economics Letters 177 (avril 2019) : 18–21. http://dx.doi.org/10.1016/j.econlet.2019.01.014.

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Munro, Moira, Ivan Turok et Mark Livingston. « Students in Cities : A Preliminary Analysis of Their Patterns and Effects ». Environment and Planning A : Economy and Space 41, n^o 8 (août 2009) : 1805–25. http://dx.doi.org/10.1068/a41133.

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This paper adds to a growing literature on the impacts of the growth in student numbers in the UK, by focusing explicitly on their spatial residential patterns and impacts on labour markets in cities. It shows that students are typically highly residentially concentrated and statistically the population of students shows a high degree of segregation from nonstudents. Turnover within student neighbourhoods is argued to be sufficiently high to cause significant neighbourhood and community disruption in many cities. Students are also shown to have very distinct labour-market characteristics, being highly concentrated within particular sectors and types of occupation. Here too they have the potential for wider impacts, including displacement effects in relation to other local young people from entry-level jobs and increasing the flexibilisation of working practices. Students are also distinctive in apparently being able to find work if they wish to, although the evidence suggests that this is probably marginally easier in more buoyant labour markets. There is much unexplained variation between cities, though, which suggests the need for more detailed local work.

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Lacroix, M. C., J. L. Servely et G. Kann. « IGF-I and IGF-II receptors in the sheep placenta : evolution during the course of pregnancy ». Journal of Endocrinology 144, n^o 1 (janvier 1995) : 179–91. http://dx.doi.org/10.1677/joe.0.1440179.

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Abstract The role of IGFs in placental growth is poorly understood. IGF-II receptors have been characterised in the ovine placenta and used extensively for radioreceptor assay, but their evolution during placental development has not been considered. In this study, binding sites for IGF-I were characterised in the ovine cotyledon by binding and cross-linking studies and the evolution of the number of IGF-I and IGF-II receptors on placentae collected on days 50, 75, 100 and 140 of pregnancy were compared. IGF-I bound onto placental membranes with a mean association constant of 1·7 nm−1 except on day 50 when a lower association constant was observed (0·8 nm−1). Scatchard analysis of the displacement curves led to a single binding site model. IGF-II was as potent as IGF-I at displacing the binding of 125I-labelled IGF-I on those membranes, whereas insulin cross-reaction was only 1%. IGF-II bound on our placental membrane preparations with the characteristics described previously and neither IGF-I nor insulin was able to displace this binding. Affinity cross-linking studies followed by SDS-PAGE under reducing conditions demonstrated that IGF-I was linked to a protein with a molecular weight of about 135 000 Da and IGF-II to a protein of 250 000 Da. The mean ± s.e.m. number of IGF-I receptors was significantly higher on days 50 and 75 than on days 100 and 140 (154 ± 12, 105 ± 11 vs 65 ±4, 48 ±3 fmol/mg, P<0·01). The number of IGF-II receptors followed the same pattern and also showed a decrease towards the end of the pregnancy that was significant (P<0·01) only by day 140 (days 50 and 75, 1 ± 0·08; day 100, 0·75 ±0·04; day 140, 0·51 ± 0·03 pmol/mg). IGF-I receptors were observed in the trophoblast cells of cotyledons removed on day 40 whereas IGF-II receptors were observed in mesodermal cells. These data suggest that IGFs are involved in the placental growth and differentiation processes and that some effects of IGF-II are probably mediated by IGF-I receptors. Journal of Endocrinology (1995) 144, 179–191

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Cornish, J., KE Callon, U. Bava, C. Lin, D. Naot, BL Hill, AB Grey et al. « Leptin directly regulates bone cell function in vitro and reduces bone fragility in vivo ». Journal of Endocrinology 175, n^o 2 (1 novembre 2002) : 405–15. http://dx.doi.org/10.1677/joe.0.1750405.

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Fat mass is an important determinant of bone density, but the mechanism of this relationship is uncertain. Leptin, as a circulating peptide of adipocyte origin, is a potential contributor to this relationship. Recently it was shown that intracerebroventricular administration of leptin is associated with bone loss, suggesting that obesity should be associated with low bone mass, the opposite of what is actually found. Since leptin originates in the periphery, an examination of its direct effects on bone is necessary to address this major discrepancy. Leptin (>10(-11) m) increased proliferation of isolated fetal rat osteoblasts comparably with IGF-I, and these cells expressed the signalling form of the leptin receptor. In mouse bone marrow cultures, leptin (>or=10(-11) m) inhibited osteoclastogenesis, but it had no effect on bone resorption in two assays of mature osteoclasts. Systemic administration of leptin to adult male mice (20 injections of 43 micro g/day over 4 weeks) reduced bone fragility (increased work to fracture by 27% and displacement to fracture by 21%, P<0.001). Changes in tibial histomorphometry were not statistically significant apart from an increase in growth plate thickness in animals receiving leptin. Leptin stimulated proliferation of isolated chondrocytes, and these cells also expressed the signalling form of the leptin receptor. It is concluded that the direct bone effects of leptin tend to reduce bone fragility and could contribute to the high bone mass and low fracture rates of obesity. When administered systemically, the direct actions of leptin outweigh its centrally mediated effects on bone, the latter possibly being mediated by leptin's regulation of insulin sensitivity.

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Saito, Leland T. « How Low–Income Residents Can Benefit from Urban Development : The LA Live Community Benefits Agreement ». City & ; Community 11, n^o 2 (juin 2012) : 129–50. http://dx.doi.org/10.1111/j.1540-6040.2012.01399.x.

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Large urban development projects highlight the vast disparities in the economic and political resources controlled by developers as compared to low–income residents. Studies have documented the negative impact of such projects on neighborhoods, such as the displacement of residents. This case study of the largest development project in contemporary downtown Los Angeles analyzes how a community coalition that included low–income residents successfully negotiated with the developer the first comprehensive Community Benefits Agreement (CBA) in the nation. This 2001 CBA addressed the interests of low–income residents and now serves as a model for major CBAs across the country. This article draws upon regime theory and urban political economy in examining the resources, organizations, and coalition composition behind the CBA. It suggests that CBAs represent a significant increase in political power for low–income residents when they ally with service sector unions concerned about permanent, living wage jobs. Low–income residents drew upon neighborhood and immigrant networks to organize even non–citizens. The L.A. coalition could also take advantage of the political opportunity provided by the fragmentation of growth interests and the strong real estate market in the city.

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Cozzi, Marco, et Giulio Fella. « Job displacement risk and severance pay ». Journal of Monetary Economics 84 (décembre 2016) : 166–81. http://dx.doi.org/10.1016/j.jmoneco.2016.11.001.

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Cornish, J., KE Callon, U. Bava, DH Coy, TB Mulvey, MA Murray, GJ Cooper, GJ Cooper et IR Reid. « Systemic administration of adrenomedullin(27-52) increases bone volume and strength in male mice ». Journal of Endocrinology 170, n^o 1 (1 juillet 2001) : 251–57. http://dx.doi.org/10.1677/joe.0.1700251.

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Adrenomedullin is a 52-amino acid peptide first described in a human phaeochromocytoma but since been found to be present in many tissues, including the vascular system and bone. Because of its structural similarity to amylin and calcitonin gene-related peptide, both of which have actions on bone cells, we have previously assessed the effects of adrenomedullin on the skeleton, and found that it increases osteoblast proliferation in vitro and bone formation following local injection in vivo. The present study carries this work forward by assessing the effects on bone of the systemic administration of a fragment of this peptide lacking the structural requirements for vasodilator activity. Two groups of 20 adult male mice received 20 injections of human adrenomedullin(27-52) 8.1 microg or vehicle over a 4-week period and bone histomorphometry and strength were assessed. In the tibia, adrenomedullin(27-52) produced increases in the indices of osteoblast activity, osteoid perimeter and osteoblast perimeter (P<0.05 for both using Student's t-test). Osteoclast perimeter was not affected. There was a 21% increase in cortical width and a 45% increase in trabecular bone volume in animals treated with adrenomedullin(27-52) (P<0.002 for both). Assessment of bone strength by three-point bending of the humerus showed both the maximal force and the displacement to the point of failure were increased in the animals treated with adrenomedullin(27-52) (P<0.03 for both). There was also a significant increase in the thickness of the epiphyseal growth plate. No adverse effects of the treatment were noted. It is concluded that adrenomedullin(27-52) acts as an anabolic agent on bone. These findings may be relevant to the normal regulation of bone mass and to the design of agents for the treatment of osteoporosis.

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Honcharenko, O. G. « FORCED MIGRATION CRISIS AND ITS DEMOGRAPHIC CONSEQUENCES ». Scientific Herald of Sivershchyna. Series : Education. Social and Behavioural Sciences 2022, n^o 2 (3 octobre 2022) : 43–53. http://dx.doi.org/10.32755/sjeducation.2022.02.043.

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Scientific novelty. The Russian-Ukrainian war led to a mass migration of the population both within the state itself and beyond its borders, which led to the emergence of the phenomenon of forced migrants, internally displaced persons, refugees, displaced persons, asylum seekers and emigrants in Ukrainian society. A large-scale wave of internally displaced persons and emigrants causes security, social, economic, financial, family and demographic problems. The article determines the trends of Ukraine’s population reduction, which is accelerating the demographic catastrophe, in particular, the increasing in population mortality due to war, huge internal displacements, the growth of emigration (refugees), the decrease in the birth rate and the probable loss of territories. The causes of the migration crisis are established, and its demographic consequences are determined, in particular: the probability of life loss; the impact of the war on the geographical distribution of the population (massive and permanent internal displacement); labor shortage and increasing burden on the pension system, decrease in birth rate (decrease in the number of women of reproductive age); increase in the number of the population of older age groups). It is also proven that the “new age structure of the country’s population” will have a smaller proportion of young people and a larger population of older age groups, which will put additional pressure on the national economy during recovery and reconstruction. Already today, the immediate demographic impact of the war on Ukraine is felt, as it has a “weak” demographic profile. Conclusions. The article substantiates that strong labor relations with employers are one of the important factors of preserving labor potential in Ukraine. However, this aspect has certain challenges for employers, in particular, creating jobs for people who have moved from the war zone (money and access to work remain the main factors for Ukrainian refugees); security guarantees and provision of housing; provision of financial support to victims and others. Key words: migration, demography, migrants, labor potential, war, age structure of the population, internally displaced persons, refugees.

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Stevens, Ann Huff. « Persistent Effects of Job Displacement : The Importance of Multiple Job Losses ». Journal of Labor Economics 15, n^o 1, Part 1 (janvier 1997) : 165–88. http://dx.doi.org/10.1086/209851.

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Jacobson, Louis, et John T. Addison. « Job Displacement : Consequences and Implications for Policy. » Industrial and Labor Relations Review 46, n^o 1 (octobre 1992) : 195. http://dx.doi.org/10.2307/2524751.

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