Tendon proper- and peritenon-derived progenitor cells have unique tenogenic properties.

IntroductionMultipotent progenitor populations exist within the tendon proper and peritenon of the Achilles tendon. Progenitor populations derived from the tendon proper and peritenon are enriched with distinct cell types that are distinguished by expression of markers of tendon and vascular or pericyte origins, respectively. The objective of this study was to discern the unique tenogenic properties of tendon proper- and peritenon-derived progenitors within an in vitro model. We hypothesized that progenitors from each region contribute differently to tendon formation; thus, when incorporated into a regenerative model, progenitors from each region will respond uniquely. Moreover, we hypothesized that cell populations like progenitors were capable of stimulating tenogenic differentiation, so we generated conditioned media from these cell types to analyze their stimulatory potentials.MethodsIsolated progenitors were seeded within fibrinogen/thrombin gel-based constructs with or without supplementation with recombinant growth/differentiation factor-5 (GDF5). Early and late in culture, gene expression of differentiation markers and matrix assembly genes was analyzed. Tendon construct ultrastructure was also compared after 45 days. Moreover, conditioned media from tendon proper-derived progenitors, peritenon-derived progenitors, or tenocytes was applied to each of the three cell types to determine paracrine stimulatory effects of the factors secreted from each of the respective cell types.ResultsThe cell orientation, extracellular domain and fibril organization of constructs were comparable to embryonic tendon. The tendon proper-derived progenitors produced a more tendon-like construct than the peritenon-derived progenitors. Seeded tendon proper-derived progenitors expressed greater levels of tenogenic markers and matrix assembly genes, relative to peritenon-derived progenitors. However, GDF5 supplementation improved expression of matrix assembly genes in peritenon progenitors and structurally led to increased mean fibril diameters. It also was found that peritenon-derived progenitors secrete factor(s) stimulatory to tenocytes and tendon proper progenitors.ConclusionsData demonstrate that, relative to peritenon-derived progenitors, tendon proper progenitors have greater potential for forming functional tendon-like tissue. Furthermore, factors secreted by peritenon-derived progenitors suggest a trophic role for this cell type as well. Thus, these findings highlight the synergistic potential of including these progenitor populations in restorative tendon engineering strategies

Empirical Research on Financial Notes to the Accounts and Earnings Management

Managers can influence the amount of net income their firm reports by variation in the application of accounting policies or by making real cash flow decisions. 'Earnings management' is the term given when such choices or decisions distort the fair presentation of earnings. Such earnings management activities can lead to negative consequences in the long-term. Accounting scandals in the past have shown that earnings management can even threaten the existence of a firm. Therefore, it is of crucial importance to detect and restrict earnings management. The notes to the accounts can provide information, which is otherwise not presented on the face of the financial statements. Especially the accounting policy disclosures improve the understanding about a firm’s current and future earnings. According to the comparability theory, there should be comparable accountings of firms in the same industry that are subject to similar economic events. Extending this theory, managers of comparable firms should translate the same economic events into similar notes to the accounts and contain similar earnings and discretionary accruals. Therefore, this PhD thesis examines whether similar notes to the accounts are negatively associated with a firm’s propensity to manage earnings. This means that the effect of similar textual accounting policy disclosures or rather notes relative to other firms in the same industry is tested on both, accrual-based and real earnings management proxies. This research uses detail-tagged XBRL notes from SEC EDGAR system as data source. To operationalize the within-industry similarity of the XBRL-formatted notes, the co-sine similarity measure was utilized in this study. Two different similarity scores of the notes are adopted. First, the full set of accounting policy disclosures and second, the revenue recognition disclosures. The key findings demonstrate that firms with more similar notes of the previous year conduct less accrual-based earnings management activities in the following fiscal year. Also, the empirical analyses show that more similar accounting policy and revenue recognition disclosures are negatively associated with real earnings management activities. Collectively, these results indicate that firms with an overall better accounting information environment as measured by more similar notes, relative to industry peers, engage in less accrual-based and real earnings management activities in the following year

The Impact of Distributed Energy Resources on the Bulk Power System: A Deeper Dive

solar photovoltaics (PV), electric storage and electric \ vehicles, demand response, combined heat and \ power, wind, fuel cells, and micro-turbines are \ typically installed on the low or medium voltage \ distribution network. Changes on the distribution \ network can have rippling effects throughout the rest \ of the power system. In this paper, we have \ calculated both traditional locational marginal \ prices (LMPs) and distributed locational marginal \ prices (DLMPs) using an optimal power flow (DC \ OPF). This paper provides an analysis of the energy \ price impacts resulting from significant additions of \ Distributed Energy Resources (DER), namely solar \ PV, electric batteries and demand response, in a \ distribution feeder. The impact is measured in terms \ of nodal approximations to DLMPs, realistic \ calculation of LMPs in the transmission system and \ overall price suppression effects that trickle down to \ consumers on the feeder. Policy implications are \ drawn concerning the potential impacts of \ penetration of DER on future planning, and \ operation of the power system as well as on energy \ markets and the environment

Highly Accurate Determination of Heterogeneously Stacked Van-der-Waals Materials by Optical Microspectroscopy

The composition of Van-der-Waals heterostructures is conclusively determined using a hybrid evaluation scheme of data acquired by optical microspectroscopy. This scheme deploys a parameter set comprising both change in reflectance and wavelength shift of distinct extreme values in reflectance spectra. Furthermore, the method is supported by an accurate analytical model describing reflectance of multilayer systems acquired by optical microspectroscopy. This approach allows uniquely for discrimination of 2D materials like graphene and hBN and, thus, quantitative analysis of Van-der-Waals heterostructures containing structurally very similar materials. The physical model features a transfer matrix method which allows for flexible, modular description of complex optical systems and may easily be extended to individual setups. It accounts for numerical apertures of applied objective lenses and a glass fiber which guides the light into the spectrometer by two individual weighting functions. The scheme is proven by highly accurate quantification of the number of layers of graphene and hBN in Van-der-Waals heterostructures. In this exemplary case, the fingerprint of graphene involves distinct deviations of reflectance accompanied by additional wavelength shifts of extreme values. In contrast to graphene the fingerprint of hBN reveals a negligible deviation in absolute reflectance causing this material being only detectable by spectral shifts of extreme values.Comment: 12 pages, 4 figure

Predicting Credit Spread Dynamics in the Norwegian Corporate Bond Market : An empirical analysis of High Yield and Investment Grade bonds in the Period 2014-2022

This thesis examines the credit spread dynamics between High Yield (HY) and Investment Grade (IG) bonds in the Norwegian corporate bond market. The sample consists of monthly pricing data for 37 distinct bonds spanning from 2014 to 2022. We apply the extended Merton model (Eom et al., 2004) to calculate model credit spreads further used in the analysis. The first part of the analysis is a regression analysis comparing the mispricing between HY and IG bonds. Applying several non-defaultrelated variables, we explore the differences in mispricing, both in terms of explanatory power and their relative magnitude. The second part of the analysis is a regression analysis aiming to predict credit spread differences between HY and IG. We find that the model underpredicts credit spreads for HY but overpredicts credit spreads for IG. Furthermore, modelled credit spreads explain 3.1% of the variance in observed credit spreads for HY bonds and 1.9% for IG bonds. We identify that both risk grades are broadly affected by the same variables but with different magnitudes. HY appears to be more sensitive to industry dynamics and market risk compared to IG. Lastly, leverage plays a pivotal role in explaining variance in credit spread differences, having an explanatory power of 83.6%.nhhma

Photon-statistics force in ultrafast electron dynamics

In strong-field physics and attosecond science, intense light induces ultrafast electron dynamics. Such ultrafast dynamics of electrons in matter is at the core of phenomena such as high harmonic generation (HHG), where these dynamics lead to emission of extreme UV bursts with attosecond duration. So far, all ultrafast dynamics of matter were understood to originate purely from the classical vector potential of the driving light, disregarding the influence of the quantum nature of light. Here we show that dynamics of matter driven by bright (intense) light significantly depend on the quantum state of the driving light, which induces an effective photon-statistics force. To provide a unified framework for the analysis & control over such a force, we extend the strong-field approximation (SFA) theory to account for non-classical driving light. Our quantum SFA (qSFA) theory shows that in HHG, experimentally feasible squeezing of the driving light can shift & shape electronic trajectories and attosecond pulses at the scale of hundreds of attoseconds. Our work presents a new degree-of-freedom for attosecond spectroscopy, by relying on nonclassical electromagnetic fields, and more generally, introduces a direct connection between attosecond science and quantum optics