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Number of results: 284
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Abstract

The Intrauterine fetal development process is complicated and affected by many regulating factors such as maternal nutritional status, transcription factors and adipokines. Adipokines are kinds of active substances secreted by adipose tissue, including more than 50 kinds of molecules. To explore the correlation between calf birth weights and adipokines including adiponectin, leptin, visfatin, and IGF-1 in cows venous and venous cord blood. Fifty-four healthy multiparous Chinese Holstein cows were used; in which, cows with a calf weight less than 40 kg were included in group A (n=9); those with a calf weight between 40 kg~45 kg were included in group B (n=25) and ≥45 kg were included in group C (n=20), venous blood and cord venous blood was collected. An ELISA kit was used to evaluate the concentration of adiponectin, leptin, visfatin, and IGF-1, correlations between index-index and index-calf birth weight were analysed. In both cows venous and cord venous blood, adiponectin, leptin, visfatin, and IGF-1 levels were significantly correlated with each other (p<0.01), and levels of these adipokines in venous blood were significantly higher than cord venous blood (p<0.01). Adiponectin, leptin, visfatin, and IGF-1 in venous cord blood were positively correlated with calf birth weights, and significantly correlated with calf birth weights respectively (p<0.01). Our study showed that adiponectin, leptin, and IGF-1 were found in venous blood and cord venous blood, and adiponectin, leptin, and IGF-1 in venous and cord venous blood potentially inter-regulated each other; adiponectin, leptin, and IGF-1 in venous blood were not significantly correlated with calf birth weights, while adiponectin, leptin, visfatin, and IGF-1 in venous cord blood were significantly correlated with calf birth weights, respectively.

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Authors and Affiliations

L. Shen
Y. Zhu
J. Xiao
J. Deng
G. Peng
Z. Zuo
S. Yu
X. Ma
Z. Zhong
Z. Ren
Z. Zhou
H. Liu
ORCID: ORCID
X. Zong
S. Cao
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Abstract

Cu–4.7 wt. % Sn alloy wire with Ø10 mm was prepared by two-phase zone continuous casting technology, and the temperature field, heat

and fluid flow were investigated by the numerical simulated method. As the melting temperature, mold temperature, continuous casting

speed and cooling water temperature is 1200 °C, 1040 °C, 20 mm/min and 18 °C, respectively, the alloy temperature in the mold is in the

range of 720 °C–1081 °C, and the solid/liquid interface is in the mold. In the center of the mold, the heat flow direction is vertically

downward. At the upper wall of the mold, the heat flow direction is obliquely downward and deflects toward the mold, and at the lower

wall of the mold, the heat flow deflects toward the alloy. There is a complex circular flow in the mold. Liquid alloy flows downward along

the wall of the mold and flows upward in the center.

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Authors and Affiliations

J. Luo
X. Liu
X. Wang
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Abstract

We investigated changes in concentrations of ADP (adiponectin), LEP (leptin), BHBA (beta-hydroxybutyric acid), NEFA (non-esterified fatty acid), Glucose (Glu) and INS (insulin) in serum of healthy perinatal dairy cows and cows with ketosis. Twenty-one healthy cows and seventeen cows with ketosis from a herd of a total 60 Holstein cows (near dry period i.e. 56 days antepartum) were selected. Blood was collected through the tail vein every 7 days, from 56 day antepartum to 56 day postpartum. Serum ADP, LEP, BHBA, NEFA, Glu, and INS concentrations were determined, and ketosis was diagnosed through serum BHBA (≥1.2 mmol/L). We showed the concentration of serum adipokines and energy balancing indices were stable during antepar- tum period. However, ADP concentration increased while LEP decreased, and there were a significant increase in cows with ketosis compared to that of in healthy cows. Serum BHBA and NEFA concentrations increased significantly at first, and then gradually decreased in both healthy cows and cows with ketosis. However, cows with ketosis showed higher concentrations of BHBA and NEFA which restored later. The serum concentration of Glu in both healthy dairy cows and cows with ketosis showed a decreasing trend. INS concentration in healthy cows was decreased while it was increased in cows with ketosis. The results reflect the extent of hypo- glycemia and lipid mobilization postpartum, suggest IR exists in cows with ketosis while serum ADP and LEP might play roles in the development of ketosis.

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Authors and Affiliations

L. Shen
B. Qian
J. Xiao
Y. Zhu
S. Hussain
J. Deng
G. Peng
Z. Zuo
L. Zou
S. Yu
X. Ma
Z. Zhong
Z. Ren
Y. Wang
ORCID: ORCID
H. Liu
ORCID: ORCID
Z. Zhou
D. Cai
Y. Hu
X. Zong
S. Cao
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Abstract

Emerging researches in humans, pigs and mice, highlighted that estrogen plays a pivotal role in self-renewal and differentiation of bone marrow mesenchymal stem cells (BMSCs). The present study aimed at evaluating effects of 17 beta-estradiol (E2) on proliferation and apoptosis of canine-derived bone marrow mesenchymal stem cells (cBMSCs) in vitro. The results showed that E2 supplementation at the concentration of 10-11 M promoted the proliferation of cBMSCs by CCK-8 assay and RT-qPCR analysis for the proliferation-related genes, with proliferating cell nuclear antigen (PCNA), cyclin-D1 (CCND1) being up-regulated and cyclin-dependent kinase inhibitor 1B (CDKN1B) being down-regulated. Contrarily, analysis of fluorescence-activated cell sorting (FACS) and RT-qPCR demonstrated that E2 supplementation above 10-11 M had inhibitory effects on the proliferation of cBMSCs and induced apoptosis. Intriguingly, cBMSCs still possessed the capability to differentiate into osteoblasts and adipocytes with 10-11 M E2 addition. Taken together, this study determined the optimal culture condition of cBMSCs in vitro, and has important implications for further understanding the regulatory effect of E2 on the self-renewal of cBMSCs, which are helpful for the clinical application of BMSCs.

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Authors and Affiliations

Z.-H. Zhou
C.-W. Gu
J. Li
X.-Y. Huang
J.-Q. Deng
L.-H. Shen
S.-Z. Cao
J.-L. Deng
Z.-C. Zuo
Y. Wang
ORCID: ORCID
X.-P. Ma
Z.-H. Ren
S.-M. Yu
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Abstract

In order to overcome the shortcomings of the dolphin algorithm, which is prone to falling into local optimum and premature convergence, an improved dolphin swarm algorithm, based on the standard dolphin algorithm, was proposed. As a measure of uncertainty, information entropy was used to measure the search stage in the dolphin swarm algorithm. Adaptive step size parameters and dynamic balance factors were introduced to correlate the search step size with the number of iterations and fitness, and to perform adaptive adjustment of the algorithm. Simulation experiments show that, comparing with the basic algorithm and other algorithms, the improved dolphin swarm algorithm is feasible and effective.

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Authors and Affiliations

Y. Li
X. Wang
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Abstract

In this paper, a semi-analytical solution for free vibration differential equations of curved girders is proposed based on their mathematical properties and vibration characteristics. The solutions of in-plane vibration differential equations are classified into two cases: one only considers variable separation of non-longitudinal vibration, while the other is a synthesis method addressing both longitudinal and non-longitudinal vibrationusing Rayleigh’s modal assumption and variable separation method. A similar approach is employed for the out-of-plane vibration, but further mathematical operations are conducted to incorporate the coupling effect of bending and twisting. In this case study, the natural frequencies of a curved girder under different boundary conditions are obtained using the two proposed methods, respectively. The results are compared with those from the finite element analysis (FEA) and results show good convergence.

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Authors and Affiliations

Y. Song
X. Chai
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Abstract

To investigate the mechanical properties of tunnel lining concrete under different moderate-low strain rates after high temperatures, uniaxial compression tests in association with ultrasonic tests were performed. Test results show that the ultrasonic wave velocity and mass loss of concrete specimen begin to sharply drop after high temperatures of 600°C and 400°C, respectively, at the strain rates of 10‒5s‒1 to 10‒2s‒1. The compressive strength and elastic modulus of specimen increase with increasing strain rate after the same temperature, but it is difficult to obtain an evident change law of peak strain with increasing strain rate. The compressive strength of concrete specimen decreases first, and then increases, but decreases again in the temperatures ranging from room temperature to 800°C at the strain rates of 10‒5s‒1 to 10‒2s‒1. It can be observed that the strain-rate sensitivity of compressive strength of specimen increases with increasing temperature. In addition, the peak strain also increases but the elastic modulus decreases substantially with increasing temperature under the same strain rate.

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Authors and Affiliations

L.X. Xiong
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Abstract

The distortion of air gap magnetic field caused by the rotor eccentricity contributes to the electromechanical coupling vibration of the brushless DC (BLDC) permanent magnet in-wheel motor (PMIWM) in electric vehicles (EV). The comfort of the BLDC in-wheel motor drive (IWMD) EV is seriously affected. To deeply investigate the electromechanical coupling vibration of the PMIWM under air gap eccentricity, the PMIWM, tyre and road excitation are analyzed first. The influence of air gap eccentricity on air gap magnetic density is investigated. The coupling law of the air gap and the unbalanced magnetic force (UMF) is studied. The coupling characteristics of eccentricity rate, air gap magnetic density, UMF, phase current and vibration acceleration are verified on the test bench in the laboratory. The mechanism of the electromechanical coupling vibration of the BLDC PMIWM under air gap static eccentricity (SE), dynamic eccentricity (DE) and hybrid eccentricity (HE) is revealed. DE and HE deteriorate the vibration acceleration amplitude, which contributes the electromechanical coupling vibration of the PMIWM. The research results provide a solid foundation for the vibration and noise suppression of the PMIWM in distributed drive EV.

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Authors and Affiliations

Y. Li
H. Wu
X. Xu
Y. Cai
X. Sun
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Abstract

Considering concrete nonlinearity, the wave height limit between small and large amplitude sloshing is defined based on the Bernoulli equation. Based on Navier-Stokes equations, the mathematical model of large amplitude sloshing is established for a Concrete Rectangle Liquid-Storage Structure (CRLSS). The results show that the seismic response of a CRLSS increases with the increase of seismic intensity. Under different seismic fortification intensities, the change in trend of wave height, wallboard displacement, and stress are the same, but the amplitudes are not. The areas of stress concentration appear mainly at the connections between the wallboards, and the connections between the wallboard and the bottom.

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Authors and Affiliations

X. Cheng
D. Li
P. Li
X. Zhang
G. Li
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Abstract

An integrated Z-source inverter for the single-phase single-stage grid-connected photovoltaic system is proposed in this paper. The inverter integrates three functional blocks including maximum-power-point-tracking, step-up/down DC-side voltage and output grid-connected current. According to the non-minimum-phase characteristic presented in DC-side and the functional demands of the system, two constant-frequency sliding-mode controllers with integral compensation are proposed to guarantee the system robustness. By using two controllers, the effects caused by the non-minimum-phase characteristic are mitigated. Under the circumstance of that the input voltage or the grid-connected current changes suddenly, the notches/protrusions following the over-shoot/ under-shoot of the DC-bus voltage are eliminated. The quality of grid-connected current is ensured. Also, a small-signal modelling method is employed to analyze the close-loop system. A 300W prototype is built in the laboratory. A solar-array simulator (SAS) is used to verify the systematic responses in the experiment. The correctness and validity of the inverter and proposed control algorithm are proved by simulation and experimental results.

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Authors and Affiliations

Z. Chen
X. Zhang
J. Pan
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Abstract

The paper is concerned with the problem of proper name-functions in Polish reportages of the 20th century. The analysis is focused on diachronic changes. For the research, two periods of Polish history were chosen: soc-realism and post-socialism epochs. The observation of onomastic material proved that culture had a significant impact on proper name functions in reportage understood as a dynamic and polyphonic speech genre. Furthermore, the proper name as a specific language sign is undoubtedly an important element which informs of the cultural and social factors, customs and traditions of a particular period. The results of this study confirm the benefits of contextualizing onomastic research within a broadly understood cultural background.
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Authors and Affiliations

Artur Rejter
ORCID: ORCID
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Abstract

The urban form creates the city structure, whose spatial values not only shape the functionality of the city, but also its identity, whose the most important determinant is the urban tissue. The subject of the study is the analysis of selected historical areas of Cracow in the scope of composition and readability of their urban structure. The analysis focuses on the identification of the most important aspects of spatial renewal processes of these spaces. These processes aimed at strengthening their potential as local centres, that can become a factor stimulating the development of the individual urban units. The increase in the attractiveness and quality of public spaces will positively affect the degree of their perception by the inhabitants and the social relations taking place in them. This in turn, influences the degree of the social involvement in development processes and the creation of more or less spontaneous, bottom-up activities.

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Authors and Affiliations

Dorota Jopek
ORCID: ORCID
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Abstract

This article concerns “living zones of the imagination”—areas of social life in which intensive “interpretive labor” is underway. Thanks to these zones, it is possible to engage in universally accepted exercises that enable a person to “see the world through the eyes of another person” and that yet do not disturb the current socio-cultural order. They provide an important basis for understanding among people, for harmonizing meanings in the sphere of social realities, and for integration that goes beyond certain permanent boundaries and hierarchies. The basic aim of the article is to prove that hospitality, understood as a value in Polish culture, could contribute to a considerable degree to the creation of such zones. The author analyzes the zones’ character, function, and meaning, paying attention to how they resist the expansion of bureaucratic ways of organizing social life. He also draws attention to the influence that an axio-normative pattern could have within specific models of behavior and cultural practices. Key words: hospitality, resistance practices, social imagination, interpretive labor
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Authors and Affiliations

Adam Pisarek
1
ORCID: ORCID

  1. Uniwersytet Śląski w Katowicach
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Abstract

This article looks at hospitality practices in the process of recreating and modifying social structure. The author seeks the general regularities and behavioral patterns that appear when people visit others and are visited, as well as how they speak of these visits, or, in Pierre Bourdieu’s language, the principles that organize practices that are part of the class habitus. For the purposes of the analysis, two comparative groups were selected: people with the highest and lowest levels of economic, social, and cultural capital. The analysis allowed several conclusions to be drawn. First, in addition to the class factor, the age or generational factor should be taken into account as it has proven to be relevant in terms of the diversity of practices. Second, the research showed that several of the practices studied were not differentiated between the groups; they turned out to be intense in the case of people with high and low levels of capital. Such patterns involved informality and freedom, the striving for agreement and group solidarity, and an aversion to aesthetics and decoration. Third, there were sometimes differentiating nuances—the general principle could be the same, but the justification or motivation behind it was different. For people with a high level of both types of capital, naturalness/honesty was an important justification and was contrasted to falsehood, artificiality, and pretentiousness. This justification seemed to be a meta-principle that permeated many other patterns of behavior.
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Authors and Affiliations

Marta Skowrońska
1
ORCID: ORCID

  1. Uniwersytet im. Adama Mickiewicza

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