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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

About 800,000 of “Cube houses” which date back to the socialist era are still in use throughout Hungary. These houses are considered to be “outdated” and they bring not only energy but also social issues. This paper presents a refurbishment design solution for the cube house, combining vernacular architecture with modern solutions within the framework of Solar Decathlon Europe 19 competition. The paper investigates the comfort and energy improvement of the refurbished design. Thermal simulation results revealed considerable improvements, which can be considered and implemented to a big proportion of family houses with analogous dimensions, under similar climate conditions.

Open access

Abstract

This paper presents an investigation on the influence of structural imperfections on the ultimate load capacity of steel welded beam-columns with class 4 cross-section under elevated temperatures. This is done by considering different amplitudes for the global and local (plate) imperfections, and different residual stresses distributions available in the literature. To this purpose, a geometrically and materially non-linear finite element model using Abaqus software has been used to determine the buckling resistance of a steel welded beam-column at elevated temperatures, using the material properties of EN1993-1-2. The imperfection sensitivity of beam-columns is reported: the influences of the amplitudes of the geometric imperfection and the patterns of the residual stress on the load capacity are compared.

Open access

Abstract

Recently, low power wide area networks are attracting a lot of attention by the research community. They are wireless technologies characterized by large coverage area, low bandwidth and long battery life. One of these low power wide area networks technologies, the long range wide area network, can be used for different monitoring applications for health, agriculture, traffic, smart city.

In this paper, different simulations and experiments are conducted to implement a low-cost long-range wide area network environmental monitoring application for Tirana city in Albania. Simulation and experimental data are compared and similar results were obtained. In the low-cost implemented system, the gateway can communicate with the sensors placed in strategic positions with long distance covered also using Radio Mobile software.

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Abstract

The contribution is dealing with run-off conditions on the lower part of the Ondava River as the capacity of the river bed is insufficient at high flow rates. The reason for the proposed research was the flood situations when protection dikes were breached. For mathematical modeling of flood wave progress, the HEC-RAS software has been applied coupling 1D and 2D modeling procedures. Results of the mathematical model of the surface water level regime in the Ondava River were compared with measured values and afterwards it was used to design further flood protection measures utilizing the existing drainage channel system and pumping stations, as well.

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Pollack Periodica
Authors: Bintul Zehra, Ali Salem, Souphavanh Senesavath, Saied Kashkash, and Zoltan Orban

Abstract

Concrete is the most widely used construction material in the world. Over ten billion tons of concrete are being produced each year resulting in exhaustion of natural materials and an enormous carbon footprint. One of the primary goals of concrete technology today is to reduce the use of Portland cement and natural fine aggregates by partially replacing them with various waste materials and by-products of industrial processes. The paper summarizes the results of a study where the partial replacement of river sand and Portland cement was successfully applied using steel slag aggregate, silica fume and glass waste.

Open access

Abstract

In this work, the thermal performance of using hybrid nanofluid of Ceria oxide and multi-walled carbon nanotube-based MOL 68 in the receiver tube of parabolic trough collector is simulated numerically. The influence of using this nanofluid under various volume concentrations and different Reynold numbers is solved numerically using computational fluid dynamics. The turbulent model's analysis is carried out based on kϵ re-normalization group and employed to find the Nusselt number and the heat transfer coefficients. The model results were validated with the previous correlation, which were used to evaluate the Nusselt number. The results showed that hybrid nanofluid enhances the heat transfer characteristics of the parabolic trough collector in comparison with the base fluid. Furthermore, even better heat transfer characteristics can be achieved with an increased volume concentration of the modified nanofluids.

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Abstract

With the reform of China's childbirth policy in recent years, a unique baby boom phenomenon has emerged, and the new-born baby has increased rapidly in China. In the process of transformation and development of contemporary cities, a complex urban environment has a significant impact on psychology and physiology. The past kindergarten architectural aesthetic experience can no longer adapt to the social development needs. Thus, how to realize the sustainable development of kindergarten architecture has become a social problem that needs to be solved urgently. In the context of Environmental Psychology, this paper investigates the construction mode of experiential kindergarten architecture and tries to explore a new paradigm of educational architecture design in China for the future.

Open access