• Title/Summary/Keyword: Damage parameters

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Effect of Alpha-Linolenic Acid with Bovine Serum Albumin or Methyl-Beta-Cyclodextrin on Membrane Integrity and Oxidative Stress of Frozen-Thawed Boar Sperm

  • Lee, Won-Hee;Kim, Wook-Hwan;Cheong, Hee-Tae;Yang, Boo-Keun;Park, Choon-Keun
    • Development and Reproduction
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    • v.23 no.1
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    • pp.11-19
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    • 2019
  • The study was conducted to investigate the effects of alpha-linolenic acid (ALA) combined with bovine serum albumin (BSA) or methyl-beta-cyclodextrin (MBCD) on plasma and acrosomal membrane damages, mitochondrial activity, morphological abnormality, motility, and oxidative stress in frozen-thawed boar sperm. In previous our study, 3 ng/mL ALA had been shown protective effect during freezing process of boar sperm. Therefore, we used 3 ng/mL ALA in present study and ALA was combined with same molar ratio of BSA or MBCD (ALA+BSA and ALA+MBCD, respectively). To confirm the effect of two carrier proteins, same volume of BSA and MBCD without ALA were added during cryopreservation. Membrane damage, mitochondrial activity, reactive oxygen species (ROS) and lipid peroxidation (LPO) levels were measured using flow cytometry, and movement of sperm tail as motility parameter and morphological abnormality were observed under light microscope. In results, all of sperm parameters were enhanced by ALA combined with BSA or MBCD compared to control groups (p<0.05). Mitochondrial activity, morphological abnormality, ROS and LPO levels in ALA+BSA or MBCD groups were no significant difference compared with ALA, BSA and MBCD treatment groups. On the other hand, plasma and acrosomal membrane intact, and sperm motility in ALA+MBCD group were higher than single treatment groups (p<0.05), whereas ALA+BSA did not differ. Our findings indicate that carrier proteins such as BSA and MBCD could improve the effect of ALA during cryopreservation of boar sperm, and treatment of ALA with carrier proteins enhance membrane integrity, mitochondrial activity through reduction of ROS-induced LPO.

Finite element based dynamic analysis of multilayer fibre composite sandwich plates with interlayer delaminations

  • Jayatilake, Indunil N.;Karunasena, Warna;Lokuge, Weena
    • Advances in aircraft and spacecraft science
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    • v.3 no.1
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    • pp.15-28
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    • 2016
  • Although the aircraft industry was the first to use fibre composites, now they are increasingly used in a range of structural applications such as flooring, decking, platforms and roofs. Interlayer delamination is a major failure mode which threatens the reliability of composite structures. Delamination can grow in size under increasing loads with time and hence leads to severe loss of structural integrity and stiffness reduction. Delamination reduces the natural frequency and as a consequence may result in resonance. Hence, the study of the effects of delamination on the free vibration behaviour of multilayer composite structures is imperative. The focus of this paper is to develop a 3D FE model and investigate the free vibration behaviour of fibre composite multilayer sandwich panels with interlayer delaminations. A series of parametric studies are conducted to assess the influence of various parameters of concern, using a commercially available finite element package. Additionally, selected points in the delaminated region are connected appropriately to simulate bolting as a remedial measure to fasten the delamination region in the aim of reducing the effects of delamination. First order shear deformation theory based plate elements have been used to model each sandwich layer. The findings suggest that the delamination size and the end fixity of the plate are the most important factors responsible for stiffness reduction due to delamination damage in composite laminates. It is also revealed that bolting the delaminated region can significantly reduce the natural frequency variation due to delamination thereby improving the dynamic performance.

Antidiabetic Activity of IH-901 in db/db Mice (db/db 마우스에서 IH-901의 항 당뇨 활성)

  • Choi, Yun-Suk;Han, Gi-Cheol;Han, Eun-Jung;Park, Keum-Joo;Park, Jong-Suk;Sung, Jong-Hwan;Chung, Sung-Hyun
    • YAKHAK HOEJI
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    • v.50 no.6
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    • pp.345-350
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    • 2006
  • The pharmacological properties of ginseng are mainly attributed to ginsenosides, the active constituents that are found in the extracts of different species of ginseng. Lately; the studies on ginsenosides are mainly focused on IH-901, a major intestinal bacterial metabolite of ginsenosides. In this study; we examined the anti-diabetic activity of IH-901 in C57BU61 db/db mice model. IH-901 was administrated orally at a dose of 20 mg/kg for 5 weeks. During the experimental period, body weight and blood glucose levels were measured every week. After 5 weeks, db/db mice were sacrificed and diabetic parameters were analyzed. IH-901 treated group showed a significant decrease in fasting blood glucose levels (from 10.5 mM to 9.4 mM), insulin resistance index (from 163.6 to 100.2) and triglyceride levels (from 115.3 to 70.1) compared to the diabetic control. In Pancreatic islets morphology; IH-901 treated group revealed much less infltrated mononuclear cells, indicating that IH-901 recovered ${\beta}$-cell damage due to hyperglycemia. In addition, IH-901 upregulated expressions of glucose transporter 4 (GLUT4) and PPAR-${\gamma}$ in skeletal muscle and adipose tissue, respectively. Taken together IH-901might be a potential anti-hyperglycemic agent with insulin sensitizing effect.

Mix design and early-age mechanical properties of ultra-high performance concrete

  • Tang, Chao-Wei
    • Advances in concrete construction
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    • v.11 no.4
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    • pp.335-345
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    • 2021
  • It is known from the literature that there are relatively few studies on the engineering properties of ultra-high performance concrete (UHPC) in early age. In fact, in order to ensure the safety of UHPC during construction and sufficient durability and long-term performance, it is necessary to explore the early behavior of UHPC. The test parameters (test control factors) investigated included the percentage of cement replaced by silica fume (SF), the percentage of cement replaced by ultra-fine silica powder (SFP), the amount of steel fiber (volume percent), and the amount of polypropylene fiber (volume percentage). The engineering properties of UHPC in the fresh mixing stage and at the age of 7 days were investigated. These properties include freshly mixed properties (slump, slump flow, and unit weight) and hardened mechanical properties (compressive strength, elastic modulus, flexural strength, and splitting tensile strength). Moreover, the effects of the experimental factors on the performance of the tested UHPC were evaluated by range analysis and variance analysis. The experiment results showed that the compressive strength of the C8 mix at the age of 7 days was highest of 111.5 MPa, and the compressive strength of the C1 mix at the age of 28 days was the highest of 128.1 MPa. In addition, the 28-day compressive strength in each experimental group increased by 13%-34% compared to the 7-day compressive strength. In terms of hardened mechanical properties, the performance of each experimental group was superior to that of the control group (without fiber and without additional binder materials), with considerable improvement, and the experimental group did not produce explosive or brittle damage after the test. Further, the flexural test process found that all test specimens exhibited deflection-hardening behavior, resulting in continued to increase carrying capacity after the first crack.

Comparative and Interactive Biochemical Effects of Sub-Lethal Concentrations of Cadmium and Lead on Some Tissues of the African Catfish (Clarias gariepinus)

  • Elarabany, Naglaa;Bahnasawy, Mohammed
    • Toxicological Research
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    • v.35 no.3
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    • pp.249-255
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    • 2019
  • Cadmium is a strong toxic heavy metal which presents in paints and liquid wastes and causes oxidative stress in fish. On the other hand, lead is widely used for different purposes, e.g. lead pipes, it targets vital organs such as liver and kidney causing biochemical alterations. The present study evaluates the effects of 60 days exposure to Cd and Pb either single or combined together in African catfish. Sixty-four fishes were divided into 3 groups and exposed to $CdCl_2$ (7.02 mg/L) or $PbCl_2$ (69.3 mg/L) or a combination of them along with control group. Activities of acid phosphatase (ACP), lactate dehydrogenase (LDH) and glucose-6-phosphate dehydrogenase (G-6-PDH) were estimated. Moreover, gill, liver and kidney were assayed for activities of superoxide dismutase (SOD), catalase (CAT) and levels of glutathione (GSH) and malondialdehyde (MDA). Individual exposure showed that both Cd and Pb significantly decreased LDH activity and SOD activity in the kidney. Pb significantly increased G-6-PDH activity and decreased GSH level in the gill. CAT activity in liver and kidney elevated significantly on Cd exposure while lead caused a significant depletion in the liver and significant elevation in the kidney. Both Cd and Pb significantly increased MDA levels in liver and kidney while Pb increased its level in gills. The combined exposure resulted in normalization of LDH, G-6-PDH activity, and CAT activity in liver and kidney as well as GSH level in both tissues and MDA in gill and kidney. The combination increased SOD activity and MDA level in liver and decreased SOD activity in kidney and GSH level in gills. In conclusion, the antioxidant system of African catfish was adversely affected by prolonged exposure to Cd and Pb. The combined exposure caused less damage than individual exposure and returned most parameters to those of controls.

Evaluation of antiproteinuric and hepato-renal protective activities of propolis in paracetamol toxicity in rats

  • Menyiy, Nawal El;Al-Waili, Noori;Ghouizi, Asmae El;Al-Waili, Wail;Lyoussi, Badiaa
    • Nutrition Research and Practice
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    • v.12 no.6
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    • pp.535-540
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    • 2018
  • BACKGROUND/OBJECTIVES: Propolis has a rich source of bioactive compounds and has renal and hepatic protective properties. The purpose of this study was to investigate the beneficial effect of hydro-ethanolic extract of propolis against paracetamol-induced liver damage and impairment of kidney function, as well as hematological changes in rats. MATERIALS/METHODS: Six groups of rats were used; the first group was served as a control; the second and third groups were treated by propolis extract at a dose of 50 and 100 mg/kg.B.WT. respectively; the fourth group was treated by paracetamol (200 mg/kg.B.WT.); the fifth group was treated by propolis (50 mg/kg.B.WT.) for eight days and then received similar dose of propolis for following seven days with paracetamol at a dose of 200 mg/kg.B.WT. daily for the seven days; and the sixth group was treated with propolis (100 mg/kg.B.WT.) for eight days and then received similar dose of propolis for following seven days with paracetamol at a dose of 200 mg/kg.B.WT. daily for the seven days. All the animals were treated for a period of 15 days. At the end of the experimental period, blood samples were collected for measurement of the liver enzymes, serum albumin, protein and creatinine, blood urea nitrogen, hematological parameters, and urine volume, protein and albumin. RESULTS: Paracetamol over dose significantly lowered hemoglobin, serum total protein, albumin, and uric acid, while it significantly increased blood creatinine, blood urea nitrogen, alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase activities, white blood cells, and platelet count as compared to the control. However, these alterations were significantly attenuated by the use of propolis extract and the effect was dose dependent. Interestingly, propolis prevented paracetamol induced proteinuria, low hemoglobin and body weight loss. CONCLUSIONS: Propolis significantly prevented paracetamol induced renal, hepatic and hematological toxicity and might be useful in the management of liver and renal diseases particularly proteinuria.

High energy swift heavy ion irradiation and annealing effects on DC electrical characteristics of 200 GHz SiGe HBTs

  • Hegde, Vinayakprasanna N.;Praveen, K.C.;Pradeep, T.M.;Pushpa, N.;Cressler, John D.;Tripathi, Ambuj;Asokan, K.;Prakash, A.P. Gnana
    • Nuclear Engineering and Technology
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    • v.51 no.5
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    • pp.1428-1435
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    • 2019
  • The total ionizing dose (TID) and non ionizing energy loss (NIEL) effects of 100 MeV phosphorous ($P^{7+}$) and 80 MeV nitrogen ($N^{6+}$) ions on 200 GHz silicon-germanium heterojunction bipolar transistors (SiGe HBTs) were examined in the total dose range from 1 to 100 Mrad(Si). The in-situ I-V characteristics like Gummel characteristics, excess base current (${\Delta}I_B$), net oxide trapped charge ($N_{OX}$), current gain ($h_{FE}$), avalanche multiplication (M-1), neutral base recombination (NBR) and output characteristics ($I_C-V_{CE}$) were analysed before and after irradiation. The significant degradation in device parameters was observed after $100MeV\;P^{7+}$ and $80MeV\;N^{6+}$ ion irradiation. The $100MeV\;P^{7+}$ ions create more damage in the SiGe HBT structure and in turn degrade the electrical characteristics of SiGe HBTs more when compared to $80MeV\;N^{6+}$. The SiGe HBTs irradiated up to 100 Mrad of total dose were annealed from $50^{\circ}C$ to $400^{\circ}C$ in different steps for 30 min duration in order to study the recovery of electrical characteristics. The recovery factors (RFs) are employed to analyse the contribution of room temperature and isochronal annealing in total recovery.

Tomato Yellow Leaf Curl China Virus Impairs Photosynthesis in the Infected Nicotiana benthamiana with βC1 as an Aggravating Factor

  • Farooq, Tahir;Liu, Dandan;Zhou, Xueping;Yang, Qiuying
    • The Plant Pathology Journal
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    • v.35 no.5
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    • pp.521-529
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    • 2019
  • Tomato yellow leaf curl China virus is a species of the widespread geminiviruses. The infection of Nicotiana benthamiana by Tomato yellow leaf curl China virus (TYLCCNV) causes a reduction in photosynthetic activity, which is part of the viral symptoms. ${\beta}C1$ is a viral factor encoded by the betasatellite DNA ($DNA{\beta}$) accompanying TYLCCNV. It is a major viral pathogenicity factor of TYLCCNV. To elucidate the effect of ${\beta}C1$ on plants' photosynthesis, we measured the relative chlorophyll (Chl) content and Chl fluorescence in TY-LCCNV-infected and ${\beta}C1$ transgenic N. benthamiana plants. The results showed that Chl content is reduced in TYLCCNV A-infected, TYLCCNV A plus $DNA{\beta}$ (TYLCCNV A + ${\beta}$)-infected and ${\beta}C1$ transgenic plants. Further, changes in Chl fluorescence parameters, such as electron transport rate, $F_v/F_m$, NPQ, and qP, revealed that photosynthetic efficiency is compromised in the aforementioned N. benthamiana plants. The presense of ${\beta}C1$ aggravated the decrease of Chl content and photosynthetic efficiency during viral infection. Additionally, the real-time quantitative PCR analysis of oxygen evolving complex genes in photosystem II, such as PsbO, PsbP, PsbQ, and PsbR, showed a significant reduction of the relative expression of these genes at the late stage of TYLCCNV A + ${\beta}$ infection and at the vegetative stage of ${\beta}C1$ transgenic N. benthamiana plants. In summary, this study revealed the pathogenicity of TYLCCNV in photosynthesis and disclosed the effect of ${\beta}C1$ in exacerbating the damage in photosynthesis efficiency by TYLCCNV infection.

Associations of nerve conduction study variables with clinical symptom scores in patients with type 2 diabetes

  • Park, Joong Hyun;Park, Jae Hyeon;Won, Jong Chul
    • Annals of Clinical Neurophysiology
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    • v.21 no.1
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    • pp.36-43
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    • 2019
  • Background: Diabetic peripheral polyneuropathy (DPN) is associated with a variety of symptoms. Nerve conduction studies (NCSs) are considered to be the gold standard of nerve damage assessments, but these studies are often dissociated from the subjective symptoms observed in DPN patients. Thus, the aim of the present study was to investigate the correlations between NCS parameters and neuropathic symptoms quantified using the Michigan Neuropathy Screening Instrument (MNSI). Methods: Patients with type 2 diabetes mellitus (T2DM) with or without symptoms of neuropathy were retrospectively enrolled. Demographic data, clinical laboratory data, MNSI score, and NCS results were collected for analysis; DPN was diagnosed based on the MNSI score (${\geq}3.0$) and abnormal NCS results. Pearson's correlation coefficients were used to evaluate the relationships between MNSI score and NCS variables. Results: The final analyses included 198 patients (115 men and 83 women) with a mean age of $62.6{\pm}12.7$ years and a mean duration of diabetes of $12.7{\pm}8.4$ years. The mean MNSI score was 2.8 (range, 0.0-9.0), and 69 patients (34.8%) were diagnosed with DPN. The MNSI score was positively correlated with the median motor nerve latency and negatively correlated with the median motor, ulnar sensory, peroneal, tibial, and sural nerve conduction velocities (NCVs). When the patients were categorized into quartiles according to MNSI score, peroneal nerve conduction velocity was significantly lower in the second MNSI quartile than in the first MNSI quartile (p = 0.001). A multivariate analysis revealed that the peroneal NCV was independently associated with MNSI score after adjusting for age, sex, and glycosylated hemoglobin A1c (HbA1c) levels. Conclusions: The present results indicate that a decrease in peroneal NCV was responsible for early sensory deficits in T2DM patients.

Performance of passive and active MTMDs in seismic response of Ahvaz cable-stayed bridge

  • Zahrai, Seyed Mehdi;Froozanfar, Mohammad
    • Smart Structures and Systems
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    • v.23 no.5
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    • pp.449-466
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    • 2019
  • Cable-stayed bridges are attractive due to their beauty, reducing material consumption, less harm to the environment and so on, in comparison with other kinds of bridges. As a massive structure with long period and low damping (0.3 to 2%) under many dynamic loads, these bridges are susceptible to fatigue, serviceability disorder, damage or even collapse. Tuned Mass Damper (TMD) is a suitable controlling system to reduce the vibrations and prevent the threats in such bridges. In this paper, Multi Tuned Mass Damper (MTMD) system is added to the Ahvaz cable stayed Bridge in Iran, to reduce its seismic vibrations. First, the bridge is modeled in SAP2000 followed with result verification. Dead and live loads and the moving loads have been assigned to the bridge. Then the finite element model is developed in OpenSees, with the goal of running a nonlinear time-history analysis. Three far-field and three near-field earthquake records are imposed to the model after scaling to the PGA of 0.25 g, 0.4 g, 0.55 g and 0.7 g. Two MTMD systems, passive and active, with the number of TMDs from 1 to 8, are placed in specific points of the main span of bridge, adding a total mass ratio of 1 to 10% to the bridge. The parameters of the TMDs are optimized using Genetic Algorithm (GA). Also, the optimum force for active control is achieved by Fuzzy Logic Control (FLC). The results showed that the maximum displacement of the center of the bridge main span reduced 33% and 48% respectively by adding passive and active MTMD systems. The RMS of displacement reduced 37% and 47%, the velocity 36% and 42% and also the base shear in pylons, 27% and 47%, respectively by adding passive and active systems, in the best cases.