• Development and Reproduction
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• v.6 no.2
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• pp.71-76
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• 2002

Present study was aimed to summary the recent reports of chromosomal technology such like a polyploidv, sex differentiation, gynogenesis, transgenic fish and gene manipulation. Triploid cells for rainbow trout and channel catfish were induced through thermal shocks of varying temperature levels and produced as a industrial use. A monosex fish with homogametic females of 15 species of high valued fish were produced by exposing to irradiation. It seemed that different irradiation was suitable to inactivate the sperm and block the formation in producing the gynogenetic diploids. Since 1985, transgenic fish have been successfully produced by microinjecting or electroporating desired foreign DNA into unfertilized or newly fertilized eggs using about 40 fish species. More recently, transgenic fish have also been produced by infecting newly fertilized eggs with pantropic, defective retroviral vectors carrying desired foreign DNA. These transgenic fish can serve as excellent experimental models for basic scientific investigations as well as in marine biotechnological applications.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.1
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• pp.366-381
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• 2020

Steganography has been successfully employed in various applications, e.g., copyright control of materials, smart identity cards, video error correction during transmission, etc. Deep learning-based steganography models can hide information adaptively through network learning, and they draw much more attention. However, the capacity, security, and robustness of the existing deep learning-based steganography models are still not fully satisfactory. In this paper, three models for different cases, i.e., a basic model, a secure model, a secure and robust model, have been proposed for different cases. In the basic model, the functions of high-capacity secret information hiding and extraction have been realized through an encoding network and a decoding network respectively. The high-capacity steganography is implemented by hiding a secret image into a carrier image having the same resolution with the help of concat operations, InceptionBlock and convolutional layers. Moreover, the secret image is hidden into the channel B of carrier image only to resolve the problem of color distortion. In the secure model, to enhance the security of the basic model, a steganalysis network has been added into the basic model to form an adversarial network. In the secure and robust model, an attack network has been inserted into the secure model to improve its robustness further. The experimental results have demonstrated that the proposed secure model and the secure and robust model have an overall better performance than some existing high-capacity deep learning-based steganography models. The secure model performs best in invisibility and security. The secure and robust model is the most robust against some attacks.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.5 s.108
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• pp.408-415
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• 2006

This paper suggests an improved system-level model of RF power amplifiers(PAs) including memory effects, and validates the suggested model by analyzing the power spectral density of the output signal with a predistortion linearizer. The original three-box(Wiener-Hammerstein) model uses input and output filters to capture RF frequency response of PAs. The adjacent spectral regrowth that occurs in three-box model can be perfectly removed by Hammerstein structure predistorter. However, the predistorter based on Hammerstein structure achieves limited performance in real PA applications due to other memory effects except RF frequency response. The spectrum of the output signal can be predicted accurately using the suggested model that changes a memoryless block in a three-box model with a memory polynomial. The proposed model accurately predicts the output spectrum density of PA with Hammerstein structure predistorter with less than 2 dB errors over ${\pm}30$ MHz adjacent channel ranges for IEEE 802.11 g WLAN signal.

• The Journal of Internal Korean Medicine
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• v.21 no.5
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• pp.697-704
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• 2000

According to herbalogical bibligraphy and literature, therapeutic effects of Achyranthis Radix on arthritis was as follows, 1. Achyranthis Radix of Amaranthaceae is divided into five species-Achyranthes japonica, A. bidentata, A. longifolia, A. fauriei, Cyathula capitata, C. officialis and the characteristic, taste, channel entry, effects and main treatments were alike. 2. Winefrying stood for repairing treatement method for Achyranthis Radix Before repairing treatment method, Achyranthis Radix had three tastes(bitter, sour, and sweet) and calm and not poisoning characteristic. After repairing treatment method, the bitter taste was disappeared, and calm and not poisoning characteristic was changed into warm characteristic. 3. Effects of Achyranthis Radix were quicking the blood and dispelling stasis, liver-kidney supplement and strengthening musculo-skeletal system. Main treatments were relief of lumbar and knee joint pain, static menstrural block and wind-cold- damp impediment. 4. Contraindication of Achyranthis Radix was sympthom caused by spleen-kidney yang vacuity, upper burner disease and lower burner hemorrhage etc. Being used in pregnant woman, it could incur abortion. 5. Contraindication of Achyranthis Radix was beef, milk and mutton. It's fear was Radix Cynanchi Stauntonii and Semen Plantaginis. It's aversion was the firefly. Herba Taraxaci, Carapax Amydae, Carapax Testudinis and Radix Cynanchi Stauntonii. From above results, I suppose Achyranthis Radix has enough herbalogical foundation and could be used to treat arthritis and it is necessary to make a profound study of it.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.479-484
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• 2005

Raynaud's syndrome causes discolorization, ischemic claudication(pain) and necrosis of the digits through insufficiency in the circulation which is induced by intermittent spasms of the digital arteries. From January, 2002 to December, 2004, 10 patients were surgically treated for Raynaud's syndrome. 9 patients were female and 1 patient was male. 2 patients showed unilateral involvement, 8 patients were operated on both hands. 6 patients had necrotic changes on the finger tips due to the disease. Ages ranged from 21 to 60 with an average of 39.1. Ischemic pain, discolorization, and cold intolerance of the digits were the common symptoms. All patients were evaluated with color doppler before the surgery. Two different procedures were applied according to the severity of the disease: Patients with decreased circulation received, what we call a limited digital sympathectomy, i.e. stripping of the adventitia of the ulnar, radial and common digital arteries. An extended procedure, radical digital sympathectomy, was performed on patients with a complete block of circulation. Stripping of the adventitia in these patients also involved the proper digital arteries. Symptoms like discolorization, ischemic pain, and cold intolerance improved immediately after the surgery. The patients did not suffer from pain even with exposure to cold weather. We conclude that digital sympathectomy could improve the symptoms in Raynaud's patients who do not respond to conservative treatment such as calcium channel blocker and other vasodilators.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.5
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• pp.255-262
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• 2005

Striatum is involved in the control of movement and habitual memory. It receives glutamatergic input from wide area of the cerebral cortex as well as an extensive serotonergic (5-hydroxytryptamine, 5-HT) input from the raphe nuclei. In our study, the effects of 5-HT on synaptic transmission were studied in the rat corticostriatal brain slice using in vitro whole-cell recording technique. 5-HT inhibited the amplitude as well as frequency of spontaneous excitatory postsynaptic currents (sEPSC) significantly, and neither ${\gamma}-aminobutyric$ acid (GABA)A receptor antagonist bicuculline (BIC), nor $N-methyl-_{D}-aspartate$ (NMDA) receptor antagonist, $_{DL}-2-amino-5-phosphonovaleric$ acid (AP-V) could block the effect of 5-HT. In the presence non-NMDA receptor antagonist, 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenxo[f] quinoxaline-7-sulfonamide (NBQX), the inhibitory effect of 5-HT was blocked. We also figured out that 5-HT change the channel kinetics of the sEPSC. There was a significant increase in the rise time during the 5-HT application. Our results suggest that 5-HT has an effect on both pre- and postsynaptic site with decreasing neurotransmitter release probability of glutamate and decreasing the sensitivity to glutamate by increasing the rise time of non-NMDA receptor mediated synaptic transmission in the corticostriatal synapses.

• Journal of Biomedical Engineering Research
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• v.28 no.3
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• pp.429-440
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• 2007

A coded excitation has been studied to improve the performance for ultrasound imaging in term of SNR, imaging frame rate, contrast to tissue ratio, and so forth. However, it requires a complicated arbitrary waveform transmitter for each active channel that is typically composed of a multi-bit Digital-to-Analog Converter (DAC) and a linear power amplifier (LPA). Not only does the LPA increase the cost and size of a transmitter block, but it consumes much power, increasing the system complexity further and causing a heating-up problem. This paper proposes an optimized 1.5bit fourth order sigma-delta modulation technique applicable to design an efficient arbitrary waveform generator with greatly reduced power dissipation and hardware. The proposed SDM can provide a required SQNR with a low over-sampling ratio of 4. To this end, the loop coefficients are optimized to minimize the quantization noise power in signal band while maintaining system stability. In addition, the decision level for the 1.5 bit quantizer is optimized for a given input waveform, which results in the SQNR improvement of more than 5dB. Computer simulation results show that the SQNR of a FM(frequency modulated) signal generated by using the proposed method is about 26dB, and the peak side-lobe level (PSL) of its compressed waveform on receive is -48dB.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.6
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• pp.649-660
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• 2018

Migraine is a neurological disorder characterized by recurrent and disabling severe headaches. Although several anticonvulsant drugs that block voltagedependent $Na^+$ channels are widely used for migraine, far less is known about the therapeutic actions of carbamazepine on migraine. In the present study, therefore, we characterized the effects of carbamazepine on tetrodotoxin-resistant (TTX-R) $Na^+$ channels in acutely isolated rat dural afferent neurons, which were identified by the fluorescent dye DiI. The TTX-R $Na^+$ currents were measured in medium-sized DiIpositive neurons using the whole-cell patch clamp technique in the voltage-clamp mode. While carbamazepine had little effect on the peak amplitude of transient $Na^+$ currents, it strongly inhibited steady-state currents of transient as well as persistent $Na^+$ currents in a concentration-dependent manner. Carbamazepine had only minor effects on the voltage-activation relationship, the voltage-inactivation relationship, and the use-dependent inhibition of TTX-R $Na^+$ channels. However, carbamazepine changed the inactivation kinetics of TTX-R $Na^+$ channels, significantly accelerating the development of inactivation and delaying the recovery from inactivation. In the current-clamp mode, carbamazepine decreased the number of action potentials without changing the action potential threshold. Given that the sensitization of dural afferent neurons by inflammatory mediators triggers acute migraine headaches and that inflammatory mediators potentiate TTX-R $Na^+$ currents, the present results suggest that carbamazepine may be useful for the treatment of migraine headaches.

• Steel and Composite Structures
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• v.27 no.5
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• pp.537-543
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• 2018

Mechanical shear connectors are commonly used to transfer longitudinal shear forces across the steel-concrete interface in composite beams. Steel pipe as a new shear connector is proposed in this research and its performance to achieve composite strength is investigated. Experimental monotonic push-out tests were carried out for this connector. Then, a nonlinear finite element model of the push-out specimens is developed and verified against test results. Further, the finite element model is used to investigate the effects of pipe thickness, length and diameter on the shear strength of the connectors. The ultimate strengths of these connectors are reported and their respective failure modes are discussed. This paper comprises of the push-out tests of ten specimens on this shear connector in both the vertical and horizontal positions in different reinforced concretes. The results of experimental tests are given as load-deformation plots. It is concluded that the use of these connectors is very effective and economical in the medium shear demand range of 150-350 KN. The dominant failure modes observed were either failure of concrete block (crushing and splitting) or shear failure of pipe connector. It is shown that the horizontal pipe is not as effective as vertical pipe shear connector and is not recommended for practical use. It is shown that pipe connectors are more effective in transferring shear forces than channel and stud connectors. Moreover, based on the parametric study, a formula is presented to predict the pipe shear connectors' capacity.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.5
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• pp.343-348
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• 2012

Blocking or regulating $K^+$ channels is important for investigating neuronal functions in mammalian brains, because voltage-dependent $K^+$ channels (Kv channels) play roles to regulate membrane excitabilities for synaptic and somatic processings in neurons. Although a number of toxins and chemicals are useful to change gating properties of Kv channels, specific effects of each toxin on a particular Kv subunit have not been sufficiently demonstrated in neurons yet. In this study, we tested electro-physiologically if heteropodatoxin2 ($HpTX_2$), known as one of Kv4-specific toxins, might be effective on various $K^+$ outward currents in CA1 neurons of organotypic hippocampal slices of rats. Using a nucleated-patch technique and a pre-pulse protocol in voltage-clamp mode, total $K^+$ outward currents recorded in the soma of CA1 neurons were separated into two components, transient and sustained currents. The extracellular application of $HpTX_2$ weakly but significantly reduced transient currents. However, when $HpTX_2$ was added to internal solution, the significant reduction of amplitudes were observed in sustained currents but not in transient currents. This indicates the non-specificity of $HpTX_2$ effects on Kv4 family. Compared with the effect of cytosolic 4-AP to block transient currents, it is possible that cytosolic $HpTX_2$ is pharmacologically specific to sustained currents in CA1 neurons. These results suggest that distinctive actions of $HpTX_2$ inside and outside of neurons are very efficient to selectively reduce specific $K^+$ outward currents.