• Title/Summary/Keyword: Helix 0

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Antagonists of Both D1 and D2 Mammalian Dopamine Receptors Block the Effects of Dopamine on Helix aspersa Neurons

  • Kim, Young-Kee;Woodruff, Michael L.
    • BMB Reports
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    • v.28 no.3
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    • pp.221-226
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    • 1995
  • Dopamine mediates inhibitory responses in Helix aspersa neurons from the right parietal lobe ("F-lobe") of the circumoesophageal ganglia. The effects appeared as a dose-dependent hyperpolarization of the plasma membrane and a decrease in the occurrence of spontaneous action potentials. The average hyperpolarization with 5 ${\mu}m$ dopamine was -12 mV (${\pm}1.5$mV, S.D., n=12). Dopamine also modulated the currents 'responsible for shaping the action potentials in these neurons. When dopamine was added and action potentials were triggered by an injection of current, the initial depolarization was slowed, the amplitude and the duration of action potentials were decreased, and the after-hyperpolarization was more pronounced. The amplitude and the duration of action potential were reduced about 15 mV and about 13% by 5 ${\mu}m$ dopamine, respectively. The effects of dopamine on the resting membrane potentials and the action potentials of Helix neurons were dose-dependent in the concentration range 0.1 ${\mu}m$ to 50 ${\mu}m$. In order to show 1) that the effects of dopamine were mediated by dopamine receptors rather than by direct action on ionic channels and 2) which type of dopamine receptor might be responsible for the various effects, we assayed the ability of mammalian dopamine receptor antagonists, SCH-23390 (antagonist of D1 receptor) and spiperone (antagonist of D2 receptor), to block the dopamine-dependent changes. The D1 and D2 antagonists partially inhibited the dopamine-dependent hyperpolarization and the decrease in action potential amplitude. They both completely blocked the decrease in action potential duration and the increase in action potential after-hyperpolarization. The dopamine-induced slowdown of the depolarization in the initial phase of the action potentials was less effected by SCH-23390 and spiperone. From the results we suggest 1) that Helix F-lobe neurons may have a single type of dopamine receptor that binds both SCH-23390 and spiperone and 2) that the dopamine receptor of Helix F-lobe neurons may be homologous with and primitive to the family of mammalian dopamine receptors.

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Assessment of Genetic Diversity of Hedera spp. Using RAPD Marker Technique (RAPD Marker를 이용한 Hedera속 식물의 다양성 조사)

  • Jung, Mi Soon;Joung, Youn Hwa;Lee, Ja Hyun;Choi, Jeong Keun;Kim, Kwang Soo;Han, Tae Ho
    • FLOWER RESEARCH JOURNAL
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    • v.16 no.1
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    • pp.28-35
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    • 2008
  • Eleven accessions of Hedera helix, three accessions of Hedera rhombea, one accession of Fatshedera lizei, and one accession of Fatsia japonica were collected and their genetic diversity was measured by using 10 RAPD primers. Approximately ninety seven percentage of polymorphism was detected, because broad germplasm, three genus, was used. Total 97 bands were scored and a dendrogram was constructed by using an UPGMA method. Accessions belonging to Hedera helix tightly clustered in one group: eight accessions showed extremely narrow genetic differences and the other three accessions also showed significant similarity. Despite of their genetic similarity, they showed morphological variations. The morphological variation with a narrow genetic differences indicated that the ivy cultivars have been indeed developed from a mutation breeding program. Genetically most unrelated Fatsia japonica showed a genetic distance of 0.63 on the average between other species. An accession from Fatshedera lizei developed by crossing between two genus, Hedera helix and Fatsia japonica, was allocated together with accessions from Hedera rhombea.

Effects of Different Light Conditions on Wintering in Evergreen Ground Covers (차광처리가 상록지피식물의 내한성에 미치는 영향)

  • Kim, Myung-Hyoe
    • Journal of agriculture & life science
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    • v.44 no.6
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    • pp.61-67
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    • 2010
  • Six evergreen ground-cover species including Ajuga reptans, Carex morrowii 'Variegata', Dianthus 'Night Star', Hedera helix 'Ivalace', Pachysandra terminalis, and Sedum rupestre, were tested for cold acclimation with three different light treatments (0, 30, and 70% of shading, respectively) to select potential candidates for over-wintering in central Korea. Among those species, Ajuga reptans, Carex morrowii 'Variegata', and Sedum rupestre performed well, which had more than 50% of survival rate in all light conditions. However, Dianthus 'Night Star' had less than 40% under any light treatment and the other two species, Hedera helix 'Ivalace' and Pachysandra terminalis, survived more than 40% only with 70% of shading condition. These results imply that those candidate species having less cold hardness in central Korea could have the potential to could over-winter as long as a proper light condition is provided.

The Unique Mechanism of SNX9 BAR Domain for Inducing Membrane Tubulation

  • Park, Joohyun;Zhao, Haiyan;Chang, Sunghoe
    • Molecules and Cells
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    • v.37 no.10
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    • pp.753-758
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    • 2014
  • Sorting nexin 9 (SNX9) is a member of the sorting nexin family of proteins and plays a critical role in clathrinmediated endocytosis. It has a Bin-Amphiphysin-Rvs (BAR) domain which can form a crescent-shaped homodimer structure that induces deformation of the plasma membrane. While other BAR-domain containing proteins such as amphiphysin and endophilin have an amphiphatic helix in front of the BAR domain which plays a critical role in membrane penetration, SNX9 does not. Thus, whether and how SNX9 BAR domain could induce the deformation of the plasma membrane is not clear. The present study identified the internal putative amphiphatic stretch in the $1^{st}$ ${\alpha}$-helix of the SNX9 BAR domain and proved that together with the N-terminal helix ($H_0$) region, this internal putative amphiphatic stretch is critical for inducing membrane tubulation. Therefore, our study shows that SNX9 uses a unique mechanism to induce the tubulation of the plasma membrane which mediates proper membrane deformation during clathrinmediated endocytosis.

Effects of Auricular Acupressure on Anxiety and Sleep among Patients Undergoing Chemotherapy for Breast Cancer (이압요법이 항암화학요법을 받는 유방암 환자의 불안 및 수면에 미치는 효과)

  • Kang, Mi-Ae;Yeo, Hyeong-Nam
    • The Korean Journal of Health Service Management
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    • v.13 no.3
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    • pp.81-92
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    • 2019
  • Objectives: This study aimed to investigate the effects of auricular acupressure on anxiety and sleep among patients undergoing chemotherapy for breast cancer. Methods: A nonequivalent control group nonsynchronized design was employed. The experimental group received auricular acupressure on specific acupoints (shenmen, heart, kidney, subcortex), and the control group received auricular acupressure on helix 1, helix 2, helix 3, and helix 4 three times a day for three weeks. A total of 60 women were divided into an experimental (n=30) and control (n=30) group. Patient recruitment occurred between May and August 2019. The collected data were analyzed by a chi-square test, paired t-test, and independent t-tests using the SPSS 21.0 program. Results: There was a significant decrease in anxiety(t=4.61, p=<.001) and increase in sleep(t=3.81, p=<.001) in the experimental group compared to the control group. Conclusions: The findings confirm that auricular acupressure is an effective nursing intervention to decrease anxiety felt by patients undergoing chemotherapy and to increase the quality of their sleep.

Effects of the Helix Angle on the Tool Deflection in End Milling (엔드밀 가공시 헬릭스각이 공구변위에 미치는 영향)

  • 맹민재;이성찬;정준기
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.373-377
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    • 2002
  • In the end milling operation the deflection of the cutter is an important factor affecting the accuracy of machining with implications on the selection of cutting parameters and economics of the operation. The deflection of the end mill was studied both experimentally with strain gauge, tool dynamometer, laser measuring apparatus and on a finite element model of the cutting using ANSYS software. The deflection of machining tool with various helix angles was studied with FEM simulation and experiment. ANSYS analysis performed on the finite element model of the end mill provides deflection results which agree within 15.0% with the experimental ones.

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Modified p-y curves to characterize the lateral behavior of helical piles

  • Hyeong-Joo, Kim;James Vincent, Reyes;Peter Rey, Dinoy;Tae-Woong, Park;Hyeong-Soo, Kim;Jun-Young, Kim
    • Geomechanics and Engineering
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    • v.31 no.5
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    • pp.505-518
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    • 2022
  • This study introduces soil resistance multipliers at locations encompassed by the zone of influence of the helix plate to consider the added lateral resistance provided to the helical pile. The zone of influence of a helix plate is a function of its diameter and serves as a boundary condition for the modified soil resistance springs. The concept is based on implementing p-multipliers as a reduction factor for piles in group action. The application of modified p-y springs in the analysis of helical piles allows for better characterization and understanding of the lateral behavior of helical piles, which will help further the development of design methods. To execute the proposed method, a finite difference program, HPCap (Helical Pile Capacity), was developed by the authors using Matlab. The program computes the deflection, shear force, bending moment, and soil resistance of the helical pile and allows the user to freely input the value of the zone of influence and Ω (a coefficient that affects the value of the p-multiplier). Results from ten full-scale lateral load tests on helical piles embedded at depths of 3.0 m with varying shaft diameters, shaft thicknesses, and helix configurations were analyzed to determine the zone of influence and the magnitude of the p-multipliers. The analysis determined that the value of the p-multipliers is influenced by the ratio between the pile embedment length and the shaft diameter (Dp), the effective helix diameter (Dh-Dp), and the zone of influence. Furthermore, the zone of influence is recommended to be 1.75 times the helix diameter (Dh). Using the numerical analysis method presented in this study, the predicted deflections of the various helical pile cases showed good agreement with the observed field test results.

Evaluation of Salt Tolerance of Three Foliage Plant as affected by Salinity Concentration in Indoor Ornamental Hydroculture (실내 관상용 물재배에서 염분농도에 따른 3가지 관엽식물의 내염성 평가)

  • Jin Hee Ju;Sun Young Park;Yong Han Yoon
    • Journal of Environmental Science International
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    • v.33 no.4
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    • pp.257-268
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    • 2024
  • This study investigated the growth characteristics of Euonymus japonicus, Hedera helix, and Peperomia puteolata treated with different calcium chloride (CaCl2) concentrations to evaluate salt tolerance limits in hydroculture cultivation. Six concentrations of CaCl2 (0, 1, 2, 5, 10, and 15 g·L-1 referred to as Cont., C1, C2, C5, C10, and C15) were applied to solution - grown plant species. The survival rate, growth index, plant height, plant width, leaf width, leaf length, number of leaves, and relative chlorophyll contents were measured at monthly intervals. Euonymus japonicus, Hedera helix, and Peperomia puteolata survived up to C2, C5, and C10 at each CaCl2 concentration. The Euonymus japonicus was higher in the C1 treatment than in the Cont. for most growth characteristics. Hedera helix had the highest leaf width, leaf length, and number of leaves in the Cont., a significant difference was observed compared with the C1 treatment. The chlorophyll content did not differ significantly between the C5 and Cont. treatments. The leaf width and length of Peperomia puteolata were greater in the C2 and C1 treatments than in the Cont., whereas the number of leaves and chlorophyll content were the highest in C5. Dry weight analysis revealed that Euonymus japonicus, Hedera helix, and Peperomia puteolata were the lowest in the Cont. treatments. Euonymus japonicus was 74% in C15, and Hedera helix, and Peperomia puteolata were analyzed at approximately 37%- 50% and 9%-14%, respectively, regardless of the concentration in the CaCl2 treatment groups. In indoor hydroponic cultivation, the salt tolerance limit concentrations of Euonymus japonicus, Hedera helix, and Peperomia puteolata are 2, 5, and 10 g·L-1, respectively, indicating that hydroculture management techniques should be applied at higher concentrations.

Evaluation of Pork Myofibrillar Protein Gel with Pork Skin Gelatin on Rheological Properties at Different Salt Concentrations

  • Lee, Chang Hoon;Chin, Koo Bok
    • Food Science of Animal Resources
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    • v.39 no.4
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    • pp.576-584
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    • 2019
  • This study was performed to evaluate the physicochemical properties of myofibrillar protein (MP) gels containing pork skin gelatin at different salt concentrations. MP gels were prepared to the different salt levels (0.15, 0.30, and 0.45 M) with or without 1.0% of pork skin gelatin. Cooking yield (CY), gel strength, shear stress were measured to determine the physical properties, and SDS-polyacrylamide gel electrophoresis, scanning electron microscopy, fourier transform infrared spectroscopy, sulfhydryl group and protein surface hydrophobicity was performed to figure out the structural changes among the proteins. The addition of gelatin into MP increased CYs and shear stress. MP at 0.45 M salt level had the highest CY and shear stress, as compared to MPs at lower salt concentrations. As the salt concentration of MP gels increased, the microstructure became the compact and wet structures, and decreased the amount of ${\alpha}-helix$/unordered structures and ${\beta}-sheet$. MP with gelatin showed a decreased amount of ${\alpha}-helix$/unordered structures and ${\beta}-sheet$ compared to MP without gelatin. The addition of gelatin to MP did not affect the sulfhydryl group, but the sulfhydryl group decreased as increased salt levels. MP mixtures containing gelatin showed a higher hydrophobicity value than those without gelatin, regardless of salt concentration. Based on these results, the addition of gelatin increased viscosity of raw meat batter and CY of MP gels for the application to low salt meat products.