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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.

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Transformation of Tools and Conservation of Architecture •

Some Researches on the Use of Digital Systems for the Intervention on the Historical Buildings

Építés - Építészettudomány
Authors: Donatella Fiorani, Marta Acierno, Silvia Cutarelli, and Adalgisa Donatelli

The use of digital technologies to study architecture and landscape has begun to represent an innovative aspect of the research when it started to allow the dynamic association (as input and output) of images and alphanumeric data: the different combination of this information through inferences and algorithms and the consequent generation of new data has freed digitisation from a strictly instrumental role making it a new methodological approach in itself.

As a matter of fact, recently architectural research has begun to take an interest in the problem ‘from within’, working not only on the application of computer tools but, more consciously, on their configuration. The work carried out by the Sapienza research group is aimed at developing ontologies and inferential models specifically dedicated to the representation of historical buildings and is devoted to the implementation of a national GIS platform for the historical centres, the Risk Map of the Italian Ministry of Cultural Heritage and Activities and Tourism.

This kind of work involves a series of methodological issues specially oriented to the definition of the role of the history of architecture in itself and its use for the conservation project. These arguments are developed within this essay, mainly focused on: type and quality of information deriving by the new procedures; interpretative components that fuel the new research methods; cost/benefit ratio in the use of ‘analogue’ and ‘digital’ approaches; future prospects of the two different (traditional and digital) investigative strategies. Moreover, both of the fields of digital research developed by the group (ontology and Risk Map) are here summarised.

A kutatásban azóta jelent meg innovatív szempontként a digitális technológiák használata az építészet és környezete tanulmányozásában, amióta a képek és alfanumerikus adatok dinamikus társítása (bemeneti és kimeneti formában) elkezdődött: az információk következtetések és algoritmusok révén létrejött különböző kombinációja, valamint az új adatok ezekből következő generálása megszabadította a digitalizálást szigorúan instrumentális szerepétől és önmagában új módszertani megközelítést hozott létre.

A közelmúltbeli építészeti kutatások tulajdonképpen „belülről” mutattak érdeklődést a probléma iránt, nemcsak a számítógépes eszközök alkalmazásával, hanem még tudatosabban a konfigurációval is foglalkoztak. A Sapienza egyetemi kutatócsoport munkájának célja kifejezetten történeti épületek bemutatására szolgáló ontológiák és következtetési modellek kifejlesztésére irányul azzal a szándékkal, hogy megvalósuljon a történeti központokra vonatkozó olasz nemzeti térinformatikai platform, az olasz Kulturális Örökség és Turizmus Minisztériuma kockázati térképe.

Ez a fajta kutatómunka módszertani problémák sorozatát foglalja magába, amelyek kifejezetten az építészettörténet szerepének meghatározására, valamint helyreállítási projektekben történő felhasználására irányulnak. Érveinket e tanulmányban fejtjük ki, elsősorban a következőkre összpontosítva: az új eljárásokból származó információ típusa és minősége; az új kutatási módszereket fellobbantó értelmező elemek; a költség-haszon arány az „analóg” és a „digitális” megközelítés alkalmazása esetén; a kétféle (hagyományos és digitális) vizsgálati stratégia jövőbeli kilátásai. Ezeken túlmenően összefoglalásra kerül a kutatócsoport által kifejlesztett digitális kutatás mindkét területe (ontológia és kockázati térkép) is.

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Abstract

Thermodynamic efficiency is a crucial factor of a power cycle. Most of the studies indicated that efficiency increases with increasing heat source temperature, regardless of heat source type. Although this assumption generally is right, when the heat source temperature is close to the critical temperature, increasing the heat source temperature can decrease efficiency. Therefore, in some cases, the increase in the source temperature, like using improved or more collectors for a solar heat source can have a double negative effect by decreasing efficiency while increasing the installation costs. In this paper, a comparison of the CO2 subcritical cycle and the Trilateral Flash Cycle will be presented to show the potential negative effect of heat source temperature increase.

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Abstract

The development of the social economy has led to the reorganization of the original layout structure and spatial functions of the city. Based on the development background of the Petite Ceinture railway space, this article conceives the attribute transformation and activation method of this industrial heritage. The proposed methodology, applied to the leftover spaces in Paris: integrating the biodiversity; softening the boundary; setting up installations. This paper investigates the relationship between the vitality of leftover space and the texture of the cities. It is proposed to try to reconnect the leftover space with the city through a multi-dimensional system corresponding to the diversified space and make good use of its unique location and internal potential.

Open access
Pollack Periodica
Authors: Ivan Baláž, Yvonna Koleková, Lýdia Moroczová, and Antonio Agüero

Abstract

In the frame of a large parametrical study metal built-up columns made from steel and made of aluminum alloy were investigated. The second order theory is used for the analysis of the battened and laced built-up columns under combined compression and bending. The bottom column ends are fixed and the upper ones are free in the case of in-plane buckling. At the column base the translation and the rotation are fixed, at the column top the translation and the rotation are free in the case of in-plane buckling. Translation is fixed and rotation is free at both column ends in out-of plane buckling. The built-up columns are considered as the columns with effective bending and smeared shear stiffness with a local bow imperfection amplitude e 0 = L/500.

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Abstract

This research work has been conducted to model the uniaxial stress-strain compressive behavior of cement-treated sand and its post-peak softening area. The cylindrical specimens were produced by using limestone powder, sand and high early strength cement. The mixtures were made by using different ratios of water to cement with fixed ratio of limestone powder to cement and cement to sand. The stress-strain behavior in post-peak zone of cement-treated is adjusted with introduction of compression softening factor. Uniaxial compressive stress-strain relationships after amending the Japanese Society of Civil Engineers model are proposed. Finite element analysis shows that the suggested model estimates well the compressive behavior of cement-treated sand.

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Abstract

Sequencing batch reactor systems in wastewater treatment is widely applied activated sludge technology. The system performance is not only dependent on the raw sewage quality and biochemical processes, but the flow pattern within the reactor has a significant impact on the treatment itself. The varying stages of the operation require different fluid flow conditions; biological stage shall be appropriately mixed, whereas low velocity zones favor the phase separation. The aim of this study was to improve sequencing batch reactor operation in order to optimize the treatment efficiency. Numerical fluid dynamic simulations were performed to determine the substrate and biomass homogeneity inside the reactor at the biological phase and the rate of the decantation was estimated at the sedimentation phase. The settling model was calibrated by field measurements. The results revealed that the hydraulic efficiency of the reactor was 87% and the achievable settled solid content was 0.9%.

Open access

Abstract

The objective of this study was to investigate the plasma concentrations of insulin-like growth factor-2 (IGF-2) as well as its expression in the uterus and ovary of healthy dogs and those with cystic endometrial hyperplasia (CEH)–pyometra complex. Group 1 (n = 10) included bitches with open cervix pyometra, while Group 2 (n = 7) consisted of clinically healthy bitches in dioestrus. The number of IGF-2 immunopositive interstitial cells was significantly higher in Group 1, whereas in Group 2 there were only two cases in which a few cells were IGF-2 immunopositive. IGF-2 immunopositivity was observed in the endometrial glandular epithelium in both groups. Additionally, interstitial fibroblasts and macrophages in the endometrium were also positive in Group 1. The concentration of plasma IGF-2 was higher in Group 1 than in Group 2 (P < 0.05). The concentration was positively correlated with IGF-2 expression in the endometrial glands (r = 0.926; P < 0.001) in Group 1. However, a negative correlation was present between plasma IGF-2 concentration and IGF-2 expression in the interstitial endocrine cells of the ovary in Group 1 (r = −0.652; P < 0.05). The results suggest that IGF-2 plays an important role during the inflammatory process occurring in bitches with CEH–pyometra complex as well as in the endometrium of healthy bitches in dioestrus.

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Abstract

Virtual reality (VR) offers a new instrument for food scientists to evaluate different aspects of food products. The possible applications range from product design testing, evaluation of the labels, effects of different placements or the evaluation of store layouts. These analyses help us to get a deeper understanding of consumers' minds. Additionally, VR can be coupled by several different tools (e.g. eye-trackers or skin conductance sensors or even electroencephalographs). However, as there have been only a limited number of applications published, there are several open questions which need to be answered. In the presented paper the authors aim i) to introduce the current knowledge on VR applications in food science by introducing several fields of applications and ii) to point out the most important questions regarding the applications of VR in food science.

Open access