Developing Regenerative Treatments for Developmental Defects, Injuries, and Diseases Using Extracellular Matrix Collagen-Targeting Peptides.

Collagen is the most widespread extracellular matrix (ECM) protein in the body and is important in maintaining the functionality of organs and tissues. Studies have explored interventions using collagen-targeting tissue engineered techniques, using collagen hybridizing or collagen binding peptides, to target or treat dysregulated or injured collagen in developmental defects, injuries, and diseases. Researchers have used collagen-targeting peptides to deliver growth factors, drugs, and genetic materials, to develop bioactive surfaces, and to detect the distribution and status of collagen. All of these approaches have been used for various regenerative medicine applications, including neovascularization, wound healing, and tissue regeneration. In this review, we describe in depth the collagen-targeting approaches for regenerative therapeutics and compare the benefits of using the different molecules for various present and future applications

Simulating the time-variable coastal upwelling during CODE 2

The time-variable coastal upwelling during CODE 2 is simulated using a mixing-advection coupled model. The agreement between model results and observations is generally good. During periods of strong equatorward wind stress, shelf water is cold and weakly stratified, and a front moves offshore; during periods of wind relaxation, surface temperature rises markedly, but the subsurface front usually does not go back toward the coast. At the onset of each wind event, a quick cooling of the surface layer is first caused by wind mixing followed closely by offshore advection of upwelled cold water. Due to the combined effect of mixing and advection, convergence occurs at the shoreward side and divergence occurs at the seaward side of the front. Consequently, a double-cell circulation is formed

Zivilgesellschaft, Gemeinwohl und Kollektivgüter

In den letzten zwei Jahrzehnten erlebten ‚Gemeinwohl’ wie ‚Zivilgesellschaft’ eine Renaissance als Topoi und wissenschaftliche Konzepte. Beide werden oft miteinander in Beziehung gebracht: Während der Zivilgesellschaft eine gemeinwohlfördernde Funktion zugeschrieben wird, dient das Gemeinwohl wiederum auch in wissenschaftlich-analytischen Konzepten der Zivilgesellschaft als Kennzeichen eines spezifisch ‚zivilgesellschaftlichen’ Handlungsmodus. Diese Gleichsetzung wird im vorliegenden Papier theoretisch wie empirisch anhand ausgewählter Fallstudien zum Gemeinwohldiskurs in Umweltkonflikten in Frage gestellt. Die vorgestellten Überlegungen beziehen sich dabei primär auf eine von Jürgen Kocka im Rahmen der Arbeitsgruppe ‚Zivilgesellschaft’ am WZB entwickelte Definition von Zivilgesellschaft. Der Bezug auf das Gemeinwohl wird insgesamt als nur begrenzt geeignet angesehen, zivilgesellschaftliches Handeln zu kennzeichnen. Dies nicht nur aufgrund seiner inhaltlichen Vagheit und normativen Aufladung, sondern auch deshalb, weil das Gemeinwohl in Nutzungskonflikten um Kollektivgüter als stehender Begriff verwendet wird. Die Frage, ob das jeweils umstrittene Gut die Eigenschaften eines privaten oder eines öffentlichen Gutes aufweist, bestimmt damit maßgeblich die diskursive Verwendung von ‚Gemeinwohl’ mit. Da zudem zivilgesellschaftliche Akteure ohnehin meist im Falle von Verteilungsfragen, die Kollektivgüter betreffen, in die öffentliche Debatte eingreifen, bietet es sich an, anstelle des Gemeinwohls die Verhandlung von Kollektivgütern in eine wissenschaftliche Konzeptualisierung zivilgesellschaftlichen Handelns aufzunehmen.As topoi and as scientific concepts, ‘common welfare’ (Gemeinwohl) and ‘civil society’ experienced a revitalisation within the last two decades. Both are often used in context of one another. While civil society is supposed to enhance the common welfare, the latter is, in return, perceived as characteristic for activities typical for civil society, even in scientific concepts. In this paper, this relationship is put into question, theoretically as well as empirically, taking into account selected case studies on the debate on ‘common welfare’ in environmental conflicts. It specifically refers to a concept of civil society developed by Jürgen Kocka within the WZB Working Group “Civil Society: historical and comparative perspectives”. It will be shown that reference to common welfare is only suitable to a limited extent in characterising ‘civil society’ activities. This is not only due to its vagueness and normative charge; moreover, the ‘common welfare’ seems to be a set phrase in the case of conflicts regarding collective goods. Whether the goods in question can be described as private or public goods apparently influences the discursive use of ‘common welfare’. Since civil society actors mostly tend to intervene in public debates concerning the distribution of collective goods, the negotiation of ‘collective goods’ rather than ‘common welfare’ should be integrated into a scientific conceptualisation of civil society

Shear dispersion in the thermocline and the saline intrusion

Over the mid-Atlantic shelf of the North America, there is a pronounced shoreward intrusion of the saltier slope water along the seasonal thermocline, whose genesis remains unexplained. Taking note of the observed broad-band baroclinic motion, we postulate that it may propel the saline intrusion via the shear dispersion. Through an analytical model, we first examine the shear-induced isopycnal diffusivity ("shear diffusivity" for short) associated with the monochromatic forcing, which underscores its varied even anti-diffusive short-term behavior and the ineffectiveness of the internal tides in driving the shear dispersion. We then derive the spectral representation of the long-term "canonical" shear diffusivity, which is found to be the baroclinic power band-passed by a diffusivity window in the log-frequency space. Since the baroclinic power spectrum typically plateaus in the low-frequency band spanned by the diffusivity window, canonical shear diffusivity is simply 1/8 of this low-frequency plateau — independent of the uncertain diapycnal diffusivity. Applied to the mid-Atlantic shelf, this canonical shear diffusivity is about 20 m2 s−1, which is sufficient to account for the observed tracer dispersion or saline intrusion in the thermocline

Hypoxic Preconditioning Enhances Survival and Proangiogenic Capacity of Human First Trimester Chorionic Villus-Derived Mesenchymal Stem Cells for Fetal Tissue Engineering.

Prenatal stem cell-based regenerative therapies have progressed substantially and have been demonstrated as effective treatment options for fetal diseases that were previously deemed untreatable. Due to immunoregulatory properties, self-renewal capacity, and multilineage potential, autologous human placental chorionic villus-derived mesenchymal stromal cells (CV-MSCs) are an attractive cell source for fetal regenerative therapies. However, as a general issue for MSC transplantation, the poor survival and engraftment is a major challenge of the application of MSCs. Particularly for the fetal transplantation of CV-MSCs in the naturally hypoxic fetal environment, improving the survival and engraftment of CV-MSCs is critically important. Hypoxic preconditioning (HP) is an effective priming approach to protect stem cells from ischemic damage. In this study, we developed an optimal HP protocol to enhance the survival and proangiogenic capacity of CV-MSCs for improving clinical outcomes in fetal applications. Total cell number, DNA quantification, nuclear area test, and cell viability test showed HP significantly protected CV-MSCs from ischemic damage. Flow cytometry analysis confirmed HP did not alter the immunophenotype of CV-MSCs. Caspase-3, MTS, and Western blot analysis showed HP significantly reduced the apoptosis of CV-MSCs under ischemic stimulus via the activation of the AKT signaling pathway that was related to cell survival. ELISA results showed HP significantly enhanced the secretion of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) by CV-MSCs under an ischemic stimulus. We also found that the environmental nutrition level was critical for the release of brain-derived neurotrophic factor (BDNF). The angiogenesis assay results showed HP-primed CV-MSCs could significantly enhance endothelial cell (EC) proliferation, migration, and tube formation. Consequently, HP is a promising strategy to increase the tolerance of CV-MSCs to ischemia and improve their therapeutic efficacy in fetal clinical applications

The late summer vertical nutrient mixing in Long Island Sound

The occurrence of vertical nutrient mixing in central Long Island Sound was simulated for the period from July 23 to August 29, 1986 using a one-dimensional mixed-layer model based on Mellor and Yamada (1974)\u27s level 2 turbulence closure scheme. During most of the study period, the water column was stratified and the nutrient fluxes through the thermocline were driven by the combined effect of the wind and the tidal mixing. The nutrient entrainment at the bottom of the thermocline was tidally induced, while that at the top of the thermocline had a pulsating character resulting from the interaction of the wind stress and wind-generated inertial currents. Near the end of the summer, the combination of strong wind stress, surface cooling and spring tide completely broke down the stratification. The relieved upward nutrient transport was an order of magnitude larger than during the stratified period, which could result in the observed phytoplankton bloom. Model results agreed well with observations, suggesting that the mixed-layer model can be used for prediction of vertical fluxes of nutrients and other dissolved materials in Long Island Sound

The effects of thermohaline circulation on wind-driven circulation in the South China Sea

Author Posting. © American Meteorological Society, 2012. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 42 (2012): 2283–2296, doi:10.1175/JPO-D-11-0227.1.The dynamic influence of thermohaline circulation on wind-driven circulation in the South China Sea (SCS) is studied using a simple reduced gravity model, in which the upwelling driven by mixing in the abyssal ocean is treated in terms of an upward pumping distributed at the base of the upper layer. Because of the strong upwelling of deep water, the cyclonic gyre in the northern SCS is weakened, but the anticyclonic gyre in the southern SCS is intensified in summer, while cyclonic gyres in both the southern and northern SCS are weakened in winter. For all seasons, the dynamic influence of thermohaline circulation on wind-driven circulation is larger in the northern SCS than in the southern SCS. Analysis suggests that the upwelling associated with the thermohaline circulation in the deep ocean plays a crucial role in regulating the wind-driven circulation in the upper ocean.G. Wang is supported by the National Science Foundation of China (NSFC Grants 41125019, 40725017, and 40976017).D.Chen is supported by grants from the Ministry of Science and Technology (2010DFA21012), the State Oceanic Administration (201105018), and the NSFC (91128204).2013-06-0