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Since the pioneering work by Whitesides, innumerable platforms that aim to spatio-selectively seed cells and control the degree of cell-cell interactions in vitro have been developed. These methods, however, have generally been technically and methodologically complex, or demanded stringent materials and conditions. In this work, we introduce zwitterionic lipids as patternable, cell-repellant masks for selectively seeding cells. The lipid masks are easily removed with a routine washing step under physiological conditions (37 °C, pH 7.4), and are used to create patterned cocultures, as well as to conduct cell migration studies. We demonstrate, via patterned cocultures of NIH 3T3 fibroblasts and HeLa cells, that HeLa cells proliferate far more aggressively than NIH 3T3 cells, regardless of initial population sizes. We also show that fibronectin-coated substrates induce cell movement akin to collective migration in NIH 3T3 fibroblasts, while the cells cultured on unmodified substrates migrate independently. Our lipid mask platform offers a rapid and highly biocompatible means of selectively seeding cells, and acts as a versatile tool for the study of cell-cell interactions.

The non-biofouling properties of a zwitterionic sulfobetaine polymer surface were easily made attractive to bioentities (e.g., proteins and cells) by metal–polyphenol coating, and spatio-selective functionalization of the zwitterionic polymer surface was achieved by using a soft lithographic technique.

We present the interactions and assembly of triblock cylinders at oil–water and air–water interfaces. ABA-type triblock cylinders with different block ratios and surface wettabilities are prepared using a micromolding method. These triblock cylinders at fluid–fluid interfaces induce complex interface deformation depending upon their relative block ratio and the surface wettability. It is observed that triblock cylinders generate octapolar interface deformation at the air–water interface, whereas the same cylinders cause quadrupolar deformation at the oil–water interface. Consequently, the interactions and assembly behavior of these triblock cylinders at each fluid interface strongly depend upon the nature of the interface deformation.

HU, one of the major nucleoid-associated proteins, interacts with the minor groove of DNA in a nonspecific manner to induce DNA bending or to stabilize bent DNA. In this study, crystal structures are reported for both free HU fromStaphylococcus aureusMu50 (SHU) and SHU bound to 21-mer dsDNA. The structures, in combination with electrophoretic mobility shift assays (EMSAs), isothermal titration calorimetry (ITC) measurements and molecular-dynamics (MD) simulations, elucidate the overall and residue-specific changes in SHU upon recognizing and binding to DNA. Firstly, structural comparison showed the flexible nature of the β-sheets of the DNA-binding domain and that the β-arms bend inwards upon complex formation, whereas the other portions are nearly unaltered. Secondly, it was found that the disruption and formation of salt bridges accompanies DNA binding. Thirdly, residue-specific free-energy analyses using the MM-PBSA method with MD simulation data suggested that the successive basic residues in the β-arms play a central role in recognizing and binding to DNA, which was confirmed by the EMSA and ITC analyses. Moreover, residue Arg55 resides in the hinge region of the flexible β-arms, exhibiting a remarkable role in their flexible nature. Fourthly, EMSAs with various DNAs revealed that SHU prefers deformable DNA. Taken together, these data suggest residue-specific roles in local shape and base readouts, which are primarily mediated by the flexible β-arms consisting of residues 50–80.

We develop highly buoyant superhydrophobic films that mimic the three-dimensional structure of lotus leaves. The high buoyancy of these structure stems from mechanically robust bubbles that significantly reduce the density of the superhydrophobic films. These highly buoyant superhydrophobic films stay afloat on water surface while carrying a load that is more than 200 times their own weight. In addition to imparting high buoyancy, the incorporation of robust hydrophilic bubbles enables the formation of free-standing structures that mimic the water-collection properties of Namib Desert beetle. We believe the incorporation of robust bubbles is a general method that opens up numerous possibilities in imparting high buoyancy to different structures that needs to stay afloat on water surfaces and can potentially be used for the fabrication of lightweight materials. (Image on the upper left reproduced with permission from Yong, J.; Yang, Q.; Chen, F.; Zhang, D.; Du, G.; Si, J.; Yun, F.; Hou, X. A Bioinspired Planar Superhydrophobic Microboat. J. Micromech. Microeng. 2014, 24, 035006).

Nanoarchitectured polymer thin films are playing an increasingly pivotal role in a wide range of areas such as interfacial reactions, biomedical devices/implants, biosensors, food packing, and marine equipment. This review highlights recent research results in the field of the non-biofouling polymer films, including current understanding of the mechanisms of non-biofouling efficacy against bioentities (for example, proteins, cells, and bacteria) under different biological conditions. We also discuss current advances in the fabrication of non-biofouling coatings and micropatterns of cells on solid substrates and suggest a guideline when designing a non-biofouling polymer films, according to application requirements.

Binding behaviors of streptavidin were investigated with different lateral packing densities of biotin-functionalized, non-biofouling pOEGMA brushes, synthesized by surface-initiated polymerization from mixed SAMs with different mole fractions of the polymerization initiator on gold surfaces.

This study was done to investigate the efficacy of a lead shield in protecting the tissues outside the primary beams, such as the breast and thyroid, by measurement of the entrance skin dose during CT of the brain, neck, abdomen, and lumbar spine. Institutional Review Board approval was obtained. This study included 150 patients (male:female 25:125, age range 15–45 years). In females, brain, lumbar spine, and abdominal CT scans, pre-/post-contrast neck CT scans, and post-contrast liver dynamic CT scans were performed. In males, brain CT scans only were performed. Breast shielding was performed in all females, and thyroid shielding was conducted in patients with brain CT. During all CT studies, the left breast or left thyroid was shielded using a lead shield, and the contralateral side was left unshielded. Thus, each breast or thyroid measurement had its own control for the same demographic data. The efficacy of the shielding of both breasts and thyroids during CT was assessed. During brain, abdominal, lumbar, pre-/post-contrast neck, and post-contrast liver dynamic CT, 33.5, 26.0, 17.4, 26.5, and 16.2 % of the breast skin dose were reduced, respectively. During brain CT, the thyroid skin dose was reduced by 17.9 % (females) and 20.6 % (males). There were statistically significant differences in the skin doses of shielded organs (p

Oxytocin (Oxt), produced in the hypothalamic paraventricular (PVN) and supraoptic nuclei (SON) for transport to and release from the posterior pituitary, was originally discovered through its role in lactation and parturition. Oxt also plays important roles in the central nervous system by influencing various behaviors. MicroRNAs (miRNAs), endogenous regulators of many genes, are a class of small noncoding RNAs that mediate post-transcriptional gene silencing. We performed miRNA expression profiling of the mouse hypothalamus by deep sequencing. Among the sequenced and cross-mapped small RNAs, expression of known miRNAs and unknown miRNAs candidates were analyzed. We investigated in detail one miRNA, miR-24, and found that it is a novel regulator of Oxt and controls both transcript and peptide levels of Oxt. These results provide insights into potential neurohypophysial hormone regulation mediated by miRNAs.

Purpose: Late-onset hypogonadism (LOH) in aging males is a clinical and biochemical syndrome characterized by a decline in serum testosterone levels. LOH results in various physical and mental disabilities. We evaluated the relationship between serum testosterone levels and symptoms of LOH. Materials and Methods: During an andropause screening program, we examined responses to the Saint Louis university androgen deficiency in aging males (ADAM) questionnaire and results on the International Index of Erectile Function (IIEF-5) in terms of clinical symptoms and evaluated serum total testosterone levels for a biochemical diagnosis of LOH in healthy community-living volunteers aged over 40 years. Results: The mean age of the 534 men was 59.1 years (range, 40 to 79 years), and their mean serum testosterone level was 464.1±171.9 ng/dL. The serum testosterone level decreased significantly with age. There was a 92.5% positive response rate to the ADAM questionnaire. The percentage of patients whose serum testosterone level was ＜350 ng/dL among those with a positive response to the ADAM questionnaire was 25.6% (137 patients). The mean serum testosterone level among patients with a positive or negative ADAM questionnaire was 472.4±198.5 ng/dL and 487.3±165.7 ng/dL, respectively (p＞0.05). There was no significant correlation between IIEF-5 scores and serum testosterone levels. Conclusions: Among men over 40 years of age, 25.6% met the clinical and biochemical diagnostic criteria for LOH. There was no relationship between serum testosterone levels and symptoms of LOH.

In tissue engineering, fabrication of 3D scaffolds with well-defined, inter-connected pores followed by culture of mammalian cells is a typical approach. In practice, however, hydrophobicity of scaffold surfaces is not suitable for cells to be adhered because of poor wettability. Especially, infiltration followed by adhesion of cells inside hydrophobic scaffolds remains as a challenge. Thus, hydrophilic conversions of the surfaces regardless of surface location are critical for success. Herein, a method to enhance infiltration and adhesion of preosteoblasts inside hydrophobic poly(ϵ-caprolactone) (PCL) scaffolds by a bio-inspired, hydroxyapatite formation is demonstrated. The approach can be a general method for controlling hydrophilicity of inner surfaces of scaffolds.

Noncoding small regulatory RNA molecules control gene expression and microRNAs provide one of the best examples in eukaryotes. However, bacterial RNAs of comparable size to eukaryotic microRNAs have received little attention. Here, we demonstrate the existence of microRNA-size, small RNAs (msRNAs) in the model bacterium Escherichia coli. We examined the small RNAs in E. coli using a deep sequencing approach, and analyzed 33.2 million small RNA clone reads after size fractionation. Bioinformatic analysis of the whole set revealed more than 400 individual msRNA species. The cellular contents of selected highly expressed msRNAs were verified by quantitative RT-PCR and northern blotting. Although, the functional significance of these RNAs is unclear, their high abundance suggests that they may play specialized roles in bacteria, analogous to miRNAs in eukaryotes.

Colloidal particles spontaneously attach to the interface between two immiscible fluids to minimize the interfacial area between the two phases. The shape and wettability of particles have a strong influence on their configuration and interactions at fluid-fluid interfaces. In this study, we investigate the behavior of asymmetrically hydrophilic Janus cylinders (or double hydrophilic Janus cylinders with two different hydrophilic regions) trapped at an air-water interface. We find that these double hydrophilic Janus cylinders with aspect ratios of 0.9, 1.2, and 2.4 adopt both end-on and tilted configurations with respect to the interface. Our numerical calculations show that the coexistence of these configurations is a result of multiple energy minima present in the attachment energy profile that can be represented as a complex energy landscape. Double hydrophilic Janus cylinders with tilted orientations induce hexapolar interface deformation, which accounts for the pair interactions between the particles as well as the nondeterministic assembly behaviors of these particles at the interface.

In this paper, we present a fabrication method of polymeric multicompartment particles via a sequential micromolding process composed of injection of photocurable solution, evaporation of volatile solvent, and photo-polymerization. Depending on the concentration of volatile solvent in photocurable solution, the volume fraction of the multicompartment particles can be controlled. Also, the repetition of the sequential micromolding process with controlled composition of photocurable solution provides controlling the number of compartment in the particles. Based on this principle, we can fabricate single particles, Janus particles and triblock particles with desired fraction of the compartment. In addition, the multicompartment particles are able to be applicable for barcode particles embedding fluorescent dyes at each compartment. The barcode particles encode information about their specific compositions and enable simple identification. These sequential micromolding method for multicompartment particles has several advantages including easy, fast, and cost effective process. We envision that the multicompartment particles have various applications such as drug storage, delivery supporters, biosensors, and advanced materials for inducing highly selective adsorption-desorption.

Free-standing thin nanoplates of Bi2Te3 and Bi2Se3 were synthesized by solvothermal method. It was demonstrated that the thickness of the nanoplates can be controlled by introducing a controlled amount of polyvinylpyrrolidone (PVP) in the synthesis reaction. PVP bonds to the polar basal planes of hexagonal crystal structure of Bi2Te3 and Bi2Se3, and they suppress the growth (speed) of the hexagonal crystals in the c-axis direction. Highly anisotropic growth yielded the formation of 2-dimensional nanostructures of nanoplates. The plates were examined directly with transmission electron microscopy (TEM) with in-situ heating. These crystalline nanoplates with extremely high width to thickness ratios were found to exhibit much lower thermal stability compared to the bulk counterpart or the conventional nanoparticles as represented by the reduced melting temperature. The melting temperature of a nanoplate decreased by more than 100 degrees C compared to the melting temperature of the bulk material. While it is widely known that the meting temperature decreases for nanoparticles with reduced sizees in all three spatial dimensions, we demonstrate that the reduction in one dimension, i.e. thickness of the platelets in the present study, is effective enough to induce much greater decrease of the melting point than the decrease as observed for the case of nanoparticles. (C) 2016 Author(s).

MicroRNAs constitute a class of small noncoding RNAs that play roles in tumorigenesis. We found that NKX2-1 protein levels were generally high in the lung cancer tissues whereas miRNA-365 expression levels were downregulated. Ectopic miR-365 expression decreased NKX2-1 expression in lung cancer cell lines. Transfection of a miR-365 mimic led to reduced proliferation of lung cancer cells; conversely, a miR-365 inhibitor slightly increased cell proliferation. The NKX2-1 overexpression significantly increased the cell proliferation by overcoming the suppressive effect of miR-365. Our data suggest that miR-365 is an important regulator of NKX2-1 and can be a target for lung cancer therapies.

The encapsulation of individual nanoparticles has gained great attention as a method for both stabilizing nanoparticles and tailoring their surface properties. In particular, the encapsulation of nanoparticles with silica shells is advantageous for bioconjugation and applications to (nano)biotechnology. Herein we report a method for constructing gold nanoparticle (AuNP)/silica core/shell hybrid structures by biomimetic silicification of silicic acids. The procedure consists of surface-initiated, atom transfer radical polymerization of 2-(dimethylamino)ethyl methacrylate (DMAEMA) from AuNPs and biomimetic polycondensation of silicic acids by using poly(DMAEMA) as a synthetic counterpart for silaffins that are found in diatoms. The resulting AuNP/silica hybrids were characterized by Fourier transform infrared spectroscopy, energy dispersive x-ray spectroscopy, UV-vis spectroscopy and transmission electron microscopy. In addition, the immobilization of biological ligands onto the hybrids was investigated for potential applications to biotechnology. As a model ligand, biotin was attached onto the AuNP/silica hybrids through substitution reaction and Michael addition reaction, and the attachment was confirmed by fluorescence microscopy after complexation with fluorescein-conjugated streptavidin.

The individual encapsulation of living cells has a great impact on the area of cell-based sensors and devices as well as fundamental studies in cell biology. In this work, living yeast cells were individually encapsulated with functionalizable, artificial polydopamine shells, inspired by an adhesive protein in mussels. Yeast cells maintained their viability within polydopamine, and the cell cycle was controlled by the thickness of the shells. In addition, the artificial shells aided the cell in offering much stronger resistance against foreign aggression, such as lyticase. After formation of the polydopamine shells, the shells were functionalized with streptavidin by utilizing the chemical reactivity of polydopamine, and the functionalized cells were biospecifically immobilized onto the defined surfaces. Our work suggests a biomimetic approach to the encapsulation and functionalization of individual living cells with covalently bonded, artificial shells.

Native chemical ligation (NCL) is an emerging chemoselective chemistry that forms an amide bond by trans-thioesterification followed by intramolecular nucleophilic rearrangement between thioester and cysteine. The reaction is simple, occurs in a mild aqueous solution, and gives near-quantitative yields of a desired product. Since the first report in 1994, most studies involving the use of NCL have focused on the total synthesis of proteins to address fundamental questions pertaining to many aspects of protein science, such as folding, mirror images, and site-specific labeling of proteins, but applications of the NCL reaction for other areas remain largely unexplored. Herein, we present a facile strategy for surface immobilization of poly(ethylene glycol) (PEG) utilizing the NCL reaction. Surface immobilization of PEG (i.e., PEGylation) plays a key role in preventing nonspecific protein adsorption on surfaces, which is crucial in a wide variety of medical devices. Using cysteine-PEG and thioester-containing phosphonic acid conjugates, we achieved efficient surface PEGylation on titanium surfaces. Ellipsometry, goniometry, and X-ray photoelectron spectroscopy (XPS) unambiguously confirmed the presence of PEGs, which provided nonfouling effects of surfaces. This study indicates that the NCL reaction will be a useful toolkit for surface bioconjugation and functionalization.

A bio-inspired approach for superhydrophobic surface modification was investigated. Hydrophilic conversion of the superhydrophobic surface was easily achieved through this method, and the superhydrophobic-hydrophilic alternating surface was generated by the method combined with soft-lithography. The resulting patterned surface showed high water adhesion property in addition to superhydrophobic property.

This paper describes a method for introducing osteoconductivity onto titanium, a widely used material for implants, as well as maintaining its non-biofouling ("bioinert") property, in the aim of increasing bioactivity of titanium for its wider applications to biomedical areas. Titanium substrates were coated with a non-biofouling poly(poly(ethylene glycol) methacrylate) (pPEGMA) by surface-initiated polymerization, and bone morphogenetic protein-2 (BMP-2) was chemically conjugated to the activated pPEGMA films. The non-biofouling property and increased bioactivity of titanium were confirmed by the maintenance of the cellular response of mesenchymal stem cells on the titanium substrates: the BMP-2-conjugated pPEGMA films induced the adhesion and differentiation of mesenchymal stem cells, while non-conjugated pPEGMA films showed the excellent resistance against the adhesion of the cells.

Gold(III) chloride was found to be a highly efficient catalyst for the cyanosilylation of various ketones and aldehydes. The reactions were complete within 30 minutes at room temperature in the presence of only one mol% gold(III) chloride, yielding the corresponding cyanohydrin trimethylsilyl ethers in very good yields. The isolated yields for the reactions of ketones were up to 98%, and the reactions of aldehydes gave 100% conversion, as monitored by 1 H NMR spectroscopy.

This paper presents adaptive digital predistortion linearization for the frequency doubler of dual band transmitter designed with DGS. The proposed dual band module operates either as an power amplifier for 2.4 GHz band, or as a frequency doubler for 5.8 GHz band according to signal frequency and bias control. The linearized frequency doubler shows significant enhancement in terms of output power, ACPR and EVM. Measured result shows that the frequency doubler has more than 26 dB ACPR improvement at 11 MHz offset from center frequency by the proposed adaptive predistotion. The EVM of the frequency doubler is 4.4% with adaptive predistortion, whereas it is 15.4% with non-adaptive predistortion. The required power back-off has decreased 7 dB to meet the IEEE 802.11 a EVM requirements with 54 Mbps data rate.

Gold had been considered to be an extremely inert metal, but recently it was found that nanometer-sized gold particles on metal-oxide supports acted as catalysts for simple organic reactions, such as oxidation and hydrogenation, even at or below room temperature. Herein, we report that gold nanoparticles (AuNPs) of zero oxidation state (Au0) are catalytically active for a C--C bond-forming reaction, the cyanosilylation of aldehydes. The AuNP-catalyzed cyanosilylation proceeded smoothly at room temperature with 0.2 wt % loading of AuNPs. The reactions of aromatic aldehydes were almost quantitative, except for benzaldehyde derivatives containing the electron-withdrawing NO2 group, and alpha,beta-unsaturated aromatic aldehydes were the most reactive substrates. The reactions also went smoothly for aliphatic aldehydes. Mechanistic studies indicated that the reactions proceeded both homogeneously and heterogeneously: homogeneous catalysis by leached gold species and heterogeneous catalysis by the adsorption of the reactants (aldehydes and trimethylsilyl cyanide) onto AuNPs. The ratio of homogeneous and heterogeneous catalysis was estimated to be approximately 4:1.

The term coloboma refers to "a notch, hole, or fissure in any ocular structure from a congenital malformation or an acquired process".1 Eyes with congenital colobomata and cataracts are at greater risk for complications during cataract surgery because of ocular malformations resulting from embryological maldevelopment.2 Given the abnormal development of the sclera, uvea, and zonules, the structural integrity of the globe may be compromised, increasing the risk of vitreous loss during cataract extraction. The development of phacoemulsification, and continuous curvilinear capsulorhexis (CCC) techniques have made it possible to improve cataract surgery outcomes. However, visual function may not become normal after surgery due to iris malformation and zonular defects. Nevertheless, the insertion of a capsular tension ring (CTR) into the capsular bag to maintain its circular contour has improved in both visual outcomes and surgical safety. The use of CTRs has been proven to be beneficial for IOL centration.3 When a zonular defect is present and a CTR is inserted at any stage of the procedure to reestablish the capsule's contour, the CTR protects against capsular fornix aspiration, consecutive zonular dialysis extension, irrigation fluid flow behind the capsule, vitreous herniation into the anterior chamber, IOL decentration and closure of the capsular opening. Our modified iris suture technique provides an acceptable functional and cosmetic repair of iris coloboma. In addition, the iris repair is beneficial for stabilization of the IOL in the event of capsular rupture. We describe our successful experience using a CTR, and the repair of the iris during cataract surgery in a patient with bilateral coloboma.

목적: 최근 골다공증과 심혈관계 질환이 서로 관련이 있다는 보고들이 있으나 10년 내 골절의 위험도가 증가된 경우 심혈관 질환의 위험도도 같이 증가하는지에 대해서는 잘알려진 바가 없다. 이에 저자들은 남성 및 폐경 후 여성에서 골밀도의 감소가 심혈관 질환 발생 위험과 연관성이 있는지, 또한 골절 위험도 증가와 심혈관계 위험도 증가 사이에 관련이 있는지를 알아보고자 하였다. 방법: 2009년 1월부터 2012년 12월까지 본원 종합 건강 검진센터에서 건강 검진을 시행한 남성 및 폐경 후 여성을 대상으로 하였으며 골밀도 및 10년 내 골절 위험도를 평가하는 FRAX, 심혈관 질환 위험을 평가하는 FRS를 측정하였다. 결과: 남성에 있어 수축기혈압, 이완기혈압, 고밀도 지단백 콜레스테롤, 저밀도 지단백 콜레스테롤, 중성지방 및 체질량지수는 FRS에 영향이 없었으며 나이 및 총 콜레스테롤, FRAX는 FRS와 양의 상관관계, 체질량지수와는 음의 상관관계를 보였다. 여성에 있어서는 나이, 수축기혈압, 이완기 혈압, 총 콜레스테롤, 고밀도 지단백 콜레스테롤, 저밀도 지단백 콜레스테롤, 중성지방, 체질량 지수 및 FRAX가 FRS와 상관관계를 나타내었다. 결론: FRAX로 나타나는 골절 위험도 증가와 심혈관계 위험도를 나타내는 FRS 증가 사이에 유의한 연관성이 관찰되었다.

In this paper, a digital predistortion technique to linearize frequency multiplier for dual-band wireless LAN transmitter is presented. The frequency multiplier is used to generate 5.8GHz wireless LAN signal by multiplying 2.9GHz input, however, it distorts the input OFDM signal severely. This paper has analyzed the nonlinear distortion of the frequency multiplier by modeling it as a memoryless Volterra system, and proposed a simple digital predistortion algorithm to get the proper 5GHz band wireless LAN signal. The linearized frequency doubler shows 20.1 dB and 19dB ACPR improvement, respectively at 11MHz and 20MHz offset from center frequency by using the proposed predistortion linearization.

This paper presents a novel dual band module which operates as amplifier or frequency doubler according to the input frequency. It satisfies the 802.11a/b/g frequency band of wireless LAN standard. A conventional dual band wireless LAN transmitter consists of the separating power amplifiers operating at each frequency band, but the proposed dual band module operates as an amplifier for the 802.11b/g signal and as a frequency doubler for the 802.11a signal according to signal frequency and bias. We have obtained stop band characteristics by using the microstrip defected ground structure (DGS) to suppress the fundamental frequency of the frequency doubler as well as the second harmonic of the amplifier. Second harmonic suppression is below -59dBc in the amplifier mode, fundamental suppression is below -35dBc in the frequency doubler mode. The designed module has 17.8dBm output at 2.4GHz and 10.1dBm power for 5.8GHz output, and shows 0.8dB and 2.8dB output power at 2.4GHz and 5.8GHz, respectively.

Department of Marine Bio-Materials & Aquaculture, Pukyong National University, Busan 608-737, Korea *E-mail: smk12@pknu.ac.kr Department of Chemistry, KAIST, Daejeon 305-701, Korea. *E-mail: ischoi@kaist.ac.kr Graduate School of Nanoscience & Technology, KAIST, Daejeon 305-701, Korea Department of Chemistry, Ewha Womans University, Seoul 120-750, Korea Received June 4, 2013, Accepted July 25, 2013

Biosilicification in diatoms and sponges potentially promises physiological, mild reaction conditions for controlling silica structures at the nanometer scale. Since Sumper et al. had isolated catalytic peptides (i.e., silaffins) from diatoms, a number of polymers bearing tertiary amine or ammonium groups have been used as a counterpart of silaffins to biomimetically synthesize silica structures. This biomimetic silicification has several advantages over conventional chemical methods. For instance, biomimetic silicification provides relatively uniform films over large areas under physiological reaction conditions without special equipment. Moreover, this method can be simply incorporated into conventional processes. As a result, recent years have witnessed a growing interest in the applications of biomimetic silicification, such as surface coating and patterning, sensors, (bio)catalysis, nanohybrids, and biotechnology. Especially, micropattern generation through biomimetic silicification has been of interest due to its potential applications in microelectronics. For example, Stone et al. generated sub-micrometer sized silica patterns by holographic two-photon-induced photopolymerization. In addition, Choi et al. reported the controlled pattern generation of silica on a solid substrate through atom-transfer radical polymerization and silicification. However, previous examples were performed on the limited kinds of materials due to the lack of versatility, and thus a versatile method of silica pattern generation has been required for wider applications. Very recently, a material-independent silica coating method was investigated by a combination of mussel-inspired polydopamine coating and subsequent diatom-inspired silicification. This method enabled us to achieve the silica coating of many diverse materials. Furthermore, it was successfully applied to the preparation of thermally stable silica/ polyethylene separators utilized in Li-ion batteries. The musseland diatom-inspired silica coating method has another advantage to use. It can be easily combined with a micromolding in capillaries (MIMIC) technique, which is a soft lithographic technique. In MIMIC technique, microchannels of poly(dimethylsiloxane) (PDMS) are filled with a solution, and the solution is then incubated for interfacial reaction onto surfaces. In the same manner, as the alkaline solution of dopamine is injected into the microchannels, polydopamine films are selectively deposited on the surface. Herein, we demonstrate a procedure for generating silica patterns by the above-mentioned method. Figure 1 shows the schematic description of the procedure. Briefly, MIMIC

This paper presents a novel dual band P-HEMT power amplifier/frequency doubler module for 2.4 GHz and 5.8 GHz wireless LAN applications. The module operates as a power amplifier for 2.4 GHz and frequency doubler for 5.8 GHz. The transmitter module has 4.5 dB amplification gain at 2.4 GHz and 3 dB multiplication gain at 5.8 GHz frequency multiplier. At 2.4 GHz band, the 2nd harmonic is about 30 dB lower than the fundamental signal, and at 5.8 GHz band the fundamental and 3rd harmonic are 22 dB lower than the signal. The 2.4 GHz amplifier satisfies the ACPR mask requirement, and the frequency doubler output needs 10 dB ACPR improvement at 11 MHz offset from center frequency by using predistortion linearization. Matlab simulation shows the possibility of digital predistortion to satisfy the ACPR requirement.

We have developed a 24 GHz side-looking vehicle detection radar. A novel signal processing algorithm is developed for speed measurement and size classification of vehicles in multiple lanes. The system has a fixed antenna and FMCW processing module. This paper presents the background theory of operation and shows some measured data using the algorithm.

A K-band voltage controlled Gunn oscillator has been designed to get the improved phase noise and broad tuning range of 19.8-26.7GHz. The bias voltage of the diode has shown an important effect on the phase noise of the oscillator. For improving the phase noise, this paper used an active filter and a low pass bias choke on the cap of the diodes. The phase noise has been improved by more than 7dB at 100kHz offset from the center frequency compared to that without the bias filter and choke.

The interest in technology valuation is revived and increasing mainly due to the lack of suitability of the traditional valuation methods in explaining the market reaction to newly-emerging knowledge-oriented companies. Moreover, many firms are now gearing their efforts to the strategic use of technology asset such as technology licensing, transfer and commercialization. Firms are also trying to enhance their technological competitiveness by re-evaluating their technology level and thus identifying the strengths/weaknesses of their technology portfolio. To accomplish this objective, the development of an integrated evaluation system for technology assets is essential. This paper presents a technology valuation system developed for a steel manufacturing company in South Korea. The valuation framework is based on: the multi-attribute evaluation of technological competitiveness using analytic hierarchical process; and the expected future benefit of the technology using four different methods of discounted cash flow estimation. The suggested framework is easily applicable to various industries where technological competitiveness should be evaluated systematically.

However, functionalizing surfaces in a material-independent manner was not demonstrated, and the oxidation chemistry of the polyphenols was not investi-gated at a molecular level due to the well-known complexity of crosslinking chemistry. Herein, we report that a plant-inspired, amine-containing small molecule called 5-pyrogallol 2-aminoethane (PAE) can perform surface functionalization in a material-independent manner. The presence of primary amine and pyrogallol moie-ties are essential for the material-independent coating ability of PAE compared to other compounds with the pyrogallol group. The PAE-functionalized surfaces are multifunctional in that they are able to trigger ring-opening polymerization, form a gold nanoshell adsorbing near infrared spectrum, and maintain long-lasting hydrophilicity on poly(dimethylsiloxane) (PDMS) surfaces. The multi-functionality of the PAE-mediated surface chemistry will be useful in many areas, such as medical device development, drug delivery, mammalian cell culture, and the development of energy storage devices.