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Abstract

Based on the current literature, the link between Achilles tendon moment arm length and running economy is not well understood. Therefore, the aim of this study was to further investigate the connection between Achilles tendon moment arm and running economy and the influence of Achilles tendon moment arm on the function of the plantarflexor muscle-tendon unit during running.

Ten male competitive marathon runners volunteered for this study. The participants ran on a treadmill at two running speeds: 3 and 3.5 m s−1. During running the oxygen consumption, lower leg kinematics, electrical activity of plantar flexor muscles, and fascicle behavior of the lateral gastrocnemius were measured simultaneously. On the second occasion, an MRI scan of the right leg was taken and used to estimate the Achilles tendon moment arm length.

There was a negative correlation between running economy and the body height normalized moment arm length at both selected speeds (r = −0.68, P = 0.014 and r = −0.70, P = 0.01). In addition, Achilles tendon moment arm length correlated with the amplitude of the ankle flexion at both speeds (r = −0.59, P = 0.03 and r = −0.60, P = 0.03) and with the electrical activity of the medial gastrocnemius muscle at 3 m s−1 speed (r = −0.62, P = 0.02). Our finding supports the concept that a longer moment arm could be beneficial for distance runners.

Open access

Abstract

In this study, the ability of microRNA-1906 (miR-1906) to attenuate bone loss in osteoporosis was evaluated by measuring the effects of a miR-1906 mimic and inhibitor on the cellular toxicity and cell viability of MC3T3‐E1 cells. Bone marrow-derived macrophage (BMM) cells were isolated from female mice, and tartrate-resistant acid phosphatase signalling was performed in miR-1906 mimic-treated, receptor-activated nuclear factor kappa-B (NF-κB) ligand (RANKL)-induced osteoclasts. In-vivo, osteoporosis was induced by ovariectomy (OVX). Rats were treated with 500 nmol/kg of the miR-1906 mimic via intrathecal administration for 10 consecutive days following surgery. The effect of the miR-1906 mimic on bone mineral density (BMD) in OVX rats was observed in the whole body, lumbar vertebrae and femur. Levels of biochemical parameters and cytokines in the serum of miR-1906 mimic-treated OVX rats were analysed. The mRNA expression of toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), p-38 and NF-κB in tibias of osteoporotic rats (induced by ovariectomy) was observed using quantitative reverse-transcription polymerase chain reaction. Treatment with the miR-1906 mimic reduced cellular toxicity and enhanced the cell viability of MC3T3‐E1 cells. Furthermore, osteoclastogenesis in miR-1906 mimic-treated, RANKL-induced osteoclast cells was reduced, whereas the BMD in the miR-1906 mimic-treated group was higher than in the OVX group of rats. Treatment with the miR-1906 mimic also increased levels of biochemical parameters and cytokines in the serum of ovariectomised rats. Finally, mRNA expression levels of TLR4, MyD88, p-38 and NF-κB were lower in the tibias of miR-1906 mimic-treated rats than in those of OVX rats. In conclusion, the miR-1906 mimic reduces bone loss in rats with ovariectomy-induced osteoporosis by regulating the TLR4/MyD88/NF‐κB pathway.

Restricted access

Abstract

The 2010–2012 euro crisis prompted a wave of institutional reforms in the European Economic and Monetary Union (EMU), and one of the most remarkable changes was the creation of a permanent bailout facility for troubled sovereigns. The birth of the European Stability Mechanism (ESM) in 2012 was preceded by harsh debates, reflecting a conflict between a German view of country-level responsibility and French-Italian calls for more risk sharing. These tensions have remained ever since, which was also highlighted by conflicts regarding the ESMs overhaul at the end of 2019. Concerns of Italy then drew attention to the fact that a wide range of issues prevented the community from finalizing the post-crisis structure of the eurozone. This paper focuses on the evolution of the EMU financial assistance framework up until the latest efforts for its reform. We analyse the impact of related policy announcements on changes in sovereign bond yields of Italy, Spain, Portugal and Ireland (i.e. the most vulnerable countries during the euro crisis). Our findings show that news on bailout arrangements significantly contributed to a contemporaneous moderation of periphery bond yields, especially in the case of shorter maturities. This result hints at the role of common facilities in supporting financial stability. To enhance this feature, a ‘package approach’ (i.e. multiple reforms together, as stressed by Italy) may well need to be considered. Such a broad perspective can help strengthen the euro area once the acute threat of the coronavirus pandemic is averted.

Open access

Abstract

Rauwolfia tetraphylla L., is an important medicinal plant in Apocynaceae family and is recognized as an alternative source to Rauwolfia serpentina L., in terms of anti-hypertensive alkaloid production i.e. reserpine. In view of this, the present study is conducted to estimate the reserpine content in different parts (leaf, stem and root) of field grown plants (2 years old), tissue cultured plantlets (R1) (two months old) and cell suspensions cultures (two months old with and without precursor feeding) of R. tetraphylla by using high performance liquid chromatography (HPLC) technique. Overall maximum content of reserpine (in %) was estimated from the root samples. Roots of field grown plants has recorded high percent of reserpine (0.39%) followed by roots of tissue cultured plantlets (0.35%) and root callus based cell suspension cultures (0.38 %) which was fed with precursor amino acid (100 mg/L of tryptophan). In control type of root callus based cell suspension cultures, reserpine content was quantified as 0.14%; by precursor feeding (100 mg/L of tryptophan) it was enhanced to 0.38%. In conclusion, the reserpine content (0.35 and 0.38%) produced by the roots of tissue cultured plantlets (R1) and 100 mg/L tryptophan fed root callus based cell suspensions was comparable to that of the reserpine content (0.39%) of root parts of field grown plants. The present study demonstrates the reserpine production by in vitro cell suspension cultures throughout the year without sacrificing the medicinal plants.

Open access

Abstract

Multinational enterprises (MNEs) use different methods and structures for base erosion and profit shifting (BEPS) to optimize the tax liability of the group. It is of great interest to the relevant countries to be able to identify such practices and react with appropriate measures. The objective of this paper is to verify whether selected MNEs engaged in the digital economy tend to shift profits from the Czech Republic to jurisdictions with lower taxation using the tax evasion rate (TER) indicator and the transactional net margin method (TNNM). Since the TER method has not been tested yet, this paper also aims to demonstrate its application on real world data and to evaluate its usability. On a sample of five MNEs, the analysis showed a potential tendency to shift profits within Europe for four MNEs (Amazon, Apple, Google and Uber) and a potential tendency to shift profits specifically from the Czech Republic for one MNE (Amazon). The analysis shows that TER is suitable as a preliminary indication of possible risks, rather than their exact quantification.

Open access

Abstract

Providers of insurance used to have no other choice than to absorb the behavioral externalities of their policy-holders. New technology coupled with the incentives of low-risk consumers has made it possible for firms to price-discriminate on the basis of behavioral risk and thus internalize behavioral externalities. While cost-internalization is generally a positive development, the introduction of behavioral tracking technologies also introduces new economic and social costs. This paper explores the economic and moral trade-offs of adopting behavioral tracking technologies in various insurance settings.

Open access

Abstract

This paper examines the drivers and the size of the shadow economies of the Czech Republic, Hungary and Poland. It also investigates the tax losses associated with these shadow economic activities in all three countries. The Multiple Indicators and Multiple Causes (MIMIC) model is applied and uses time series data covering the period 1990–2019. The key findings show that the sizes of the shadow economies of the Czech Republic, Hungary and Poland are 10.44, 11.18 and 20.47% respectively. The results also show that the average size of the shadow economies between 1990–2019 was 14.92% in the Czech Republic, 18.72% in Hungary and 22.85% in Poland. The Czech Republic loses 3.13% of tax revenue from goods and services and 2.83% from incomes and profits as a result of the shadow economy, while Hungary loses 5.05% of tax revenue from goods and services and 1.68% from incomes and profits. Poland loses 5.25% of tax revenue from goods and services and 4.34% from incomes and profits.

Open access

Abstract

For the further development and more efficient operation of the sharing economy, a fast and inexpensive peer-to-peer payment system is an essential element. The aim of this study is to outline a prototype that ensures the automation and decentralization of processes through smart contracts without blockchain technology. The model has been built based on the narrative that a community currency created through smart contracts can promote genuine practices of sharing as opposed to the profit-oriented approach that most of the currently operating sharing economy platforms have. Features of the model, such as ease of use, high-speed transactions without transaction cost are benefits that can provide a more efficient alternative to the traditional or to the cryptocurrency-based centralized sharing economy platforms.

Open access