• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.2
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• pp.91-95
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• 2009

To understand the effect of attachment substrate on the growth of benthic microalgae, we experimentally investigated the growth of benthic microalgae Nitzschia sp. (Jinhae Bay strain) with additions of glass beads in different sizes. The glass beads used in this study are 0.09-0.15 mm (G1), 0.25-0.50 mm (G2), 0.75-1.00 mm (G3) and 1.25-1.65 mm (G4). No addition of glass beads used as controls. Highest specific growth rate (0.37/day) and maximum cell density ($9,232{\pm}840$ cells/mL) of Nitzschia sp. showed at the smallest glass beads (G1), and the specific growth rate and maximum cell density were decreasing with increasing size of glass beads (specific growth rate and maximum cell density of G4 was 0.24/day and $6,397{\pm}524$ cells/mL, respectively). Moreover, specific growth rate of the control experiment (0.23/day) was significantly lower than their of G1 to G3 experiment. The results indicated that the attachment substrate for benthic microalgae as Nitzschia sp. is important factor which affecting the growth rate as well as cell density. Therefore, the physiological experiment of benthic microalgae seems to be necessary to preliminary experiment, which is addition or not of the attachment suitable substrate and the grain size for the target species of benthic microalgae.

• Journal of Environmental Health Sciences
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• v.24 no.2
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• pp.104-109
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• 1998

The objective of this study was to examine the effect of polymer coating on the initial microorganism attachment and the biofilm growth. Such as nonion(polyacrylamine), anion(CMC-Na) and cation polymer coagulant(chitosan and PEI) were used for coating material of the support carrier(acryl plate). When polymer coagulant was coated with 5, 10, 20, 35, 50, 100 and 200 mg/l on the surface of acryl plate, initial microorganism attachment increased and optimum concentration for the attachment was 35 mg/l. Biofilm growth experiments were conducted with the substrate loading of 12.7gSCOD/$m^2\cdot$ day using RBC. The polymer coagulants such as CMC-Na, polyacrylamide, PEI and chitosan coating on the acryl plate facilitated the biofilm growth of microorganisms. Until the biofilm dry weight grows up to 0. 0038g/cm$^2$, biofilm growth on the plate coated with cation polymer like chitosan was better than that on the coated plate of nonion(polyacrylamine), anion(CMC-Na) polymer coagulant.

• Animal cells and systems
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• v.16 no.6
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• pp.479-487
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• 2012

Biological attachment device is optimized in insect legs for attachment onto the variety of natural substrate. We have studied the microstructural characteristics of the tarsal appendages in the ladybug Harmonia axyridis using scanning electron microscopy to reveal the attachment system of their legs. The attachment devices are composed of claws and adhesive pads. The claws are connected with pretarsal segment, and their apical diverged hooks are developed to hold rough substrates. In contrast, the adhesive pads have an adhesive function onto smooth surface. The pads are interspersed at the ventral part of each tarsomere, and are composed of two kinds of hairy setae. The discoid tip seta (DtS) has a spoon-shaped endplate usually with a rounded concave structure, whereas the pointed tip seta (PtS) has a pointed tip, usually with a hooked endplate. While the PtS is broadly localized concentrically on the marginal area of both the proximal and distal pads, the DtS can be seen at the central areas of each adhesive pad except for the hind legs. Our findings demonstrate the presence of the direction-dependence pattern of the fibrillar system as well as a functional modification of the tenent setae to achieve proper contact with almost any kind of substrates.

• Journal of Environmental Science International
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• v.21 no.1
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• pp.105-111
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• 2012

The effects of substrate size on the growth of microphytobenthos Achnanthes sp., Amphora sp., Navicula sp. and Nitzschia sp. were examined using glass beads in order for phytoremediation in the benthic layer of coastal waters. The glass beads used in this study were 0.09~0.15 mm (G.B 1), 0.25~0.50 mm (G.B 2), 0.75~1.00 mm (G.B 3) and 1.25~1.65 mm (G.B 4). No addition of glass bead used as control. The specific growth rate and maximum cell density of four microphytobenthos species were increasing with decreasing size of glass beads. Moreover, the control experiment without added attachment substrates showed the lowest specific growth rate and maximum cell density. Therefore, the suitable attachment substrates for mass culture of microphytobenthos seems to be important in order for phytoremediation using microphytobenthos.

• Journal of Adhesion and Interface
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• v.5 no.2
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• pp.31-42
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• 2004

Many animals possess on their legs adhesive pads, which have undergone evolutionary optimization to be able to attach to variable substrates and to control adhesive forces during locomotion. Insect adhesive pads are either relatively smooth or densely covered with specialized adhesive hairs. Theoretical models predict that adhesion can be increased by splitting the contact zone into many microscopic, elastic subunits, which provides a functional explanation for the widespread 'hairy' design. In many hairy and all smooth attachment systems, the adhesive contact is mediated by a thin film of liquid secretion between the cuticle and the substrate. By using interference reflection microscopy (IRM), the thickness and viscosity of the secretion film was estimated in Weaver ants (Oecophylla smaragdina). 'Footprint' droplets deposited on glass are hydrophobic and form low contact angles. IRM of insect pads in contact showed that the adhesive liquid is an emulsion consisting of hydrophilic, volatile droplets dispersed in a persistent, hydrophobic phase. I tested predictions derived from film thickness and viscosity by measuring friction forces of Weaver ants on a smooth substrate. The measured friction forces were much greater than expected assuming a homogenous film between the pad and the surface. The findings indicate that the rubbery pad cuticle directly interacts with the substrate. To achieve intimate contact between the cuticle and the surface, secretion must drain away, which may be facilitated by microfolds on the surface of smooth insect pads. I propose a combined wet adhesion/rubber friction model of insect surface attachment that explains both the presence of a significant static friction component and the velocity-dependence of sliding friction.

• Microbiology and Biotechnology Letters
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• v.23 no.3
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• pp.282-287
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• 1995

Integrase (Int) carries out the cutting and resealing of attachment (att) site DNA via a covalent Int-DNA intermediate. A family of synthetic substrate DNAs was designed to accumulate Int-DNA intermediate. Int-DNA intermediates accumulated by half substrate was analyzed by SDS- KCI precipitation and restriction digestion. The results showed that Int-half DNA intermediate was circular and contained covalently bound Int molecule. Int-DNA intermediates were also trapped with three other kinds of synthetic substrates.

• Journal of Biomedical Engineering Research
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• v.13 no.2
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• pp.155-164
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• 1992

Attachment and growth of mouse flbroblast cells on block copolypeptides were studied in the pres once or absence of serum proteins. Cells are rapidly attached to she polymer surface within 30 min regardless of substrate in the presence of serum. The number of flbroblast cells attached on the poly mer surface coated by collagen was larger than thats on the bare surface. Attachment of cells Is as a whole suppressed to a low level by the addltion of sodium azide in the absence of serum. Thls suE gests that the active attachment of cells requires the biological metabolism taking place on polymer substrates. In the presence of serum protein, flbroblast cells are more rapidly grown on the bolck co polymer consisting of poly(T-benzyl L-glutamate) (PBLG) and polyoxypropylene(POP) than on other block copolymers. These results were in agreement wish the data obatlned by an Inverted ml croscope.

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1917-1923
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• 2004

Although the proteolytic activity of the Cu(II) complex of cyclen (Cyc) is greatly enhanced upon attachment to a cross-linked polystyrene (PS), the Cu(II)Cyc-containing PS derivatives reported previously hydrolyzed only a very limited number of proteins. The PS-based artificial metalloproteases can overcome thermal, mechanical, and chemical instabilities of natural proteases, but the narrow substrate selectivity of the artificial metalloproteases limits their industrial application. In the present study, artificial metalloproteases exhibiting broad substrate selectivity were synthesized by attaching Cu(II)Cyc to a PS derivative using linkers with various structures in an attempt to facilitate the interaction of various protein substrates with the PS surface. The new artificial metalloproteases hydrolyzed all of the four protein substrates (albumin, myoglobin, ${\gamma}$-globulin, and lysozyme) examined, manifesting $k_{cat}/K_m$ values of 28-1500 $h_{-1}M_{-1}$ at 50 $^{\circ}C$. The improvement in substrate selectivity is attributed to steric and/or polar interaction between the bound protein and the PS surface as well as the hydrophobicity of the microenvironment of the catalytic centers.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.200-207
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• 2007

In vitro rumen incubation studies were conducted to determine effects of initial pH on bacterial attachment and fiber digestion. Ruminal fluid pH was adjusted to 5.7, 6.2 and 6.7, and three major fibrolytic bacteria attached to rice straw in the mixed culture were quantified with real-time PCR. The numbers of attached and unattached Fibrobacter succinogenes, Ruminococcus flavefaciens and Ruminocococcus albus were lower (p<0.05) at initial pH of 5.7 without significant difference between those at higher initial pH. Lowering incubation media pH to 5.7 also increased bacterial numbers detached from substrate regardless of bacterial species. Dry matter digestibility, gas accumulation and total VFA production were pH-dependent. Unlike bacterial attachment, maintaining an initial pH of 6.7 increased digestion over initial pH of 6.2. After 48 h in vitro rumen fermentation, average increases in DM digestion, gas accumulation, and total VFA production at initial pH of 6.2 and 6.7 were 2.8 and 4.4, 2.0 and 3.0, and 1.2 and 1.6 times those at initial pH of 5.7, respectively. The lag time to reach above 2% DM digestibility at low initial pH was taken more times (8 h) than at high and middle initial pH (4 h). Current data clearly indicate that ruminal pH is one of the important determinants of fiber digestion, which is modulated via the effect on bacterial attachment to fiber substrates.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.3
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• pp.61-67
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• 2020

In this paper, we calculated the warpage of bare substrates and chip attached substrates by using FEM (Finite Element Method), and compared and analyzed the effect of the chips' attachment on warpage. Also, the effects of layer thickness of substrates for reducing warpage were analyzed and the conditions of layer thickness were analyzed by signal-to-noise ratio of Taguchi method. According to the analysis results, the direction of warpage pattern in substrates can change when chips are attached. Also, the warpage decreases as the difference in the CTE (coefficient of thermal expansion) between the top and bottom of the package decreases and the stiffness of the package increases after chips are loaded. In addition, according to the impact analysis of design parameters on substrates where chips are not attached, in order to reduce warpage, the inner layers of the circuit layer Cu1 and Cu4 has be controlled first, and then concentrated on the thickness of the solder resist on the bottom side and the thickness of the prepreg layer between Cu1 and Cu2.