10,003 research outputs found
Skin Cell Proliferation Stimulated by Microneedles
A classical wound may be defined as a disruption of tissue integrity. Wounds, caused by trauma from accidents or surgery, that close via secondary intention rely on the biological phases of healing, i.e., hemostasis, inflammation, proliferation, and remodeling (HIPR). Depending on the wound type and severity, the inflammation phase begins immediately after injury and may last for an average of 7â14 days. Concurrent with the inflammation phase or slightly delayed, cell proliferation is stimulated followed by the activation of the remodeling (maturation) phase. The latter phase can last as long as 1 year or more, and the final healed state is represented by a scar tissue, a cross-linked collagen formation that usually aligns collagen fibers in a single direction. One may assume that skin microneedling that involves the use of dozens or as many as 200 needles that limit penetration to 1.5 mm over 1 cm2 of skin would cause trauma and bleeding followed by the classical HIPR. However, this is not the case or at least the HIPR phases are significantly curtailed and healing never ends in a scar formation. Conversely dermabrasion used in aesthetic medicine for improving skin quality is based on âablationâ (destruction or wounding of superficial skin layers), which requires several weeks for healing that involves formation of new skin layers. Such procedures provoke an acute inflammatory response. We believe that a less intense inflammatory response occurs following microneedle perforation of the skin. However, the mechanism of action of microneedling appears to be different. Here we review the potential mechanisms by which microneedling of the skin facilitates skin repair without scarring after the treatment of superficial burns, acne, hyperpigmentation, and the non-advancing periwound skin surrounding the chronic ulcerations of the integument
Equivalence after extension for compact operators on Banach spaces
In recent years the coincidence of the operator relations equivalence after
extension and Schur coupling was settled for the Hilbert space case, by showing
that equivalence after extension implies equivalence after one-sided extension.
In this paper we investigate consequences of equivalence after extension for
compact Banach space operators. We show that generating the same operator ideal
is necessary but not sufficient for two compact operators to be equivalent
after extension. In analogy with the necessary and sufficient conditions on the
singular values for compact Hilbert space operators that are equivalent after
extension, we prove the necessity of similar relationships between the
-numbers of two compact Banach space operators that are equivalent after
extension, for arbitrary -functions.
We investigate equivalence after extension for operators on
-spaces. We show that two operators that act on different
-spaces cannot be equivalent after one-sided extension. Such
operators can still be equivalent after extension, for instance all invertible
operators are equivalent after extension, however, if one of the two operators
is compact, then they cannot be equivalent after extension. This contrasts the
Hilbert space case where equivalence after one-sided extension and equivalence
after extension are, in fact, identical relations.
Finally, for general Banach spaces and , we investigate consequences
of an operator on being equivalent after extension to a compact operator on
. We show that, in this case, a closed finite codimensional subspace of
must embed into , and that certain general Banach space properties must
transfer from to . We also show that no operator on can be
equivalent after extension to an operator on , if and are
essentially incomparable Banach spaces
The Price of Ethics: Evidence from Socially Responsible Mutual Funds
This paper estimates the price of ethics by studying the risk-return relation in socially responsible investment (SRI) funds. Consistent with investors paying a price for ethics, SRI funds in many European and Asia-Pacific countries strongly underperform domestic benchmark portfolios by about 5% per annum, although UK and US SRI funds do not significantly underperform their benchmarks. The underperformance of SRI funds does not seem to be driven by the loadings on an ethical risk factor. SRI funds do not suffer a cost of reduced selectivity nor do SRI funds managers time the market. There is mixed evidence of a smart money effect: SRI investors are unable to identify the funds that will outperform in the future, whereas they show some fund-selection ability in identifying ethical funds that will perform poorly. The screening activities of SRI funds have a significant impact on fundsâ riskadjusted returns and loadings on risk factors: corporate governance and social screens generate better risk-adjusted returns whereas other screens (e.g. environmental ones) yield significantly lower returns.ethics;mutual funds;socially responsible investing;investment screens;smart money;risk loadings
Socially Responsible Investments: Methodology, Risk and Performance
This paper surveys the literature on socially responsible investments (SRI). Over the past decade, SRI has experienced an explosive growth around the world. Particular to the SRI funds is that both financial goals and social objectives are pursued. While corporate social responsibility (CSR) - defined as good corporate governance, sound environmental standards, and good management towards stakeholder relations - may create value for shareholders, participating in other social and ethical issues is likely to destroy shareholder value. Furthermore, the risk-adjusted returns of SRI funds in the US and UK are not significantly different from those of conventional funds, whereas SRI funds in Continental Europe and Asia-Pacific strongly underperform benchmark portfolios. Finally, the volatility of money-flows is lower in SRI funds than of conventional funds, and SRI investorsâ decisions to invest in an SRI fund are less affected by management fees than the decisions by conventional fund investors.socially responsible investments;ethical investing;corporate social responsibility;mutual funds;performance evaluation;money-flows;investment screens;mutual funds
The Price of Ethics: Evidence from Socially Responsible Mutual Funds
This paper estimates the price of ethics by studying the risk-return relation in socially responsible investment (SRI) funds. Consistent with investors paying a price for ethics, SRI funds in many European and Asia-Pacific countries strongly underperform domestic benchmark portfolios by about 5% per annum, although UK and US SRI funds do not significantly underperform their benchmarks. The underperformance of SRI funds does not seem to be driven by the loadings on an ethical risk factor. SRI funds do not suffer a cost of reduced selectivity nor do SRI funds managers time the market. There is mixed evidence of a smart money effect: SRI investors are unable to identify the funds that will outperform in the future, whereas they show some fund-selection ability in identifying ethical funds that will perform poorly. The screening activities of SRI funds have a significant impact on fundsâ riskadjusted returns and loadings on risk factors: corporate governance and social screens generate better risk-adjusted returns whereas other screens (e.g. environmental ones) yield significantly lower returns.ethics;mutual funds;socially responsible investing;investment screens;smart money;risk loadings
Socially Responsible Investments: Methodology, Risk Exposure and Performance
This paper surveys the literature on socially responsible investments (SRI). Over the past decade, SRI has experienced an explosive growth around the world. Particular to the SRI funds is that both financial goals and social objectives are pursued. While corporate social responsibility (CSR) - defined as good corporate governance, sound environmental standards, and good management towards stakeholder relations - may create value for shareholders, participating in other social and ethical issues is likely to destroy shareholder value. Furthermore, the risk-adjusted returns of SRI funds in the US and UK are not significantly different from those of conventional funds, whereas SRI funds in Continental Europe and Asia-Pacific strongly underperform benchmark portfolios. Finally, the volatility of money-flows is lower in SRI funds than of conventional funds, and SRI investorsâ decisions to invest in an SRI fund are less affected by management fees than the decisions by conventional fund investors.socially responsible investments;ethical investing;corporate social responsibility;mutual funds;performance evaluation;money-flows;investment screens;mutual funds
Is Ethical Money Financially Smart?
Little is known about how investors select socially responsible investment (SRI) funds.Investors in SRI funds may care more about social or ethical issues in their investment decisions than about fund performance.This paper studies the money-flows into and out of the SRI funds around the world.We find that ethical money chases past returns.In contrast to conventional funds' investors, SRI investors care less about the funds' riskiness and fees.Funds characterized by shareholder activism and by in-house SRI research attract more stable investors. Membership of a large SRI fund family creates higher flow volatility due to the lower fees to reallocate money within the fund family.SRI funds receiving most of the money-inflows perform worse in the future, which is consistent with theories of decreasing returns to scale in the mutual fund industry.Finally, funds employing a higher number of SRI screens to model their investment universe receive larger money-inflows and perform better in the future than focused funds.money-flows;ethical funds;socially responsible investing;persistence in performance;investment screens;corporate governance screens;SRI
Bottom and charm production at LHC and RHIC
We study bÂŻb and cÂŻc production and the influence of nuclear shadowing at LHC and RHIC energies. We find a significant reduction in the production cross section of both charm and bottom at RHIC and LHC. Bound states such as and J/psi are suppressed by this reduction in the charm production cross sections. Therefore, J/psi suppression may not be useful as a signature for the quark gluon plasma. PACS: 12.38.Mh, 25.75.-q, 24.85.+p, 14.65.D
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