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Colletotrichum scovillei is a virulent pathogen and the dominant species causing anthracnose of chili pepper in many Asian countries. Three strains of this pathogen, Coll-524, Coll-153 and Coll-365, show varied virulence on chili pepper fruit. Among the three strains, Coll-365 showed significant defects in growth and virulence. To decipher the genetic variations among these strains and identify genes contributing to growth and virulence, in this study, comparative genomic analysis and gene transformation to verify gene function were applied. The genomes of the three strains were sequenced and Coll-524 had 1.3% and 1.5% more genes than Coll-153 and Coll-365, respectively. Compared to Coll-524 and Coll-153, Coll-365 had numerous gene losses including 33 effector genes that are distributed in different scaffolds and a cluster of 14 genes in a 34-kb genomic fragment. Through gene transformation, three genes in the 34-kb fragment were identified to have functions in growth and/or virulence of C. scovillei. Gene 15019 encoding a protein related to phospholipase A2-activating protein enhanced the growth of Coll-365. A combination of 15019 with one transcription factor gene 15022 and one C6 zinc finger domain-containing protein gene 15029 was found to enhance the pathogenicity of Coll-365. Introduction of gene 15215, which encodes a LysM domain-containing protein, into Coll-365 caused a reduction in the germination rate of Coll-365. In conclusion, the higher virulent strain Coll-524 had more genes and encoded more pathogenicity related proteins and transposable elements than the other two strains, which may contribute to the high virulence of Coll-524. In addition, the absence of the 34-kb fragment plays a critical role in the defects of growth and virulence of strain Coll-365.Author SummaryColletotrichum scovillei is a highly virulent and dominant pathogen causing anthracnose of chili that leads to significant economic loss in chili production in many Asia countries. In this study we focus on finding the gene differences of three C. scovillei strains with different pathogenicity in chili pepper infection and verifying the function of some genes in the lowest virulence strain. We sequenced them and did gene annotation and genome comparison. We setup a simple mathematical method to identify gene variations between strong and weak virulence strains. Our results show that the lowest virulence strain has less pathogenicity-related genes. We also found that the absence of 14 genes in a compact genomic fragment was part of the reason of growth and virulence defect of the lowest virulence strain. We identified four genes that play roles on fungal growth and/or virulence on chili pepper. We also found a group of effector genes that specifically appear in species collected form infected chili in C. acutatum species complex. Our research provides detailed information for why the three strains have different virulence on chili pepper.

In this work, defect-free and high mechanical strength nickel films are deposited at a high growth rate using a high concentration sulfamate bath for applications in fabrication of MEMS components. Effects of the applied current density on the morphology, average grain size, Vickers hardness, micro-mechanical property, and thickness distribution are studied. The average grain size is refined to a minimum value when the current density is increased from 10 to 20 mA/cm2. The finest grain size obtained is 349.8 nm. The grain refinement effect is a result of the promoted nucleation rate as the applied current density increased. When the current density is beyond 20 mA/cm2, overpotential of the nickel reduction reaction is lowered because of the promoted hydrogen evolution and causes coarsening of the average grain size. The film electroplated at 20 mA/cm2 shows a high growth rate at 0.296 μm/min, the highest Vickers hardness at 371 HV, and the yield stress evaluated by micro-compression test is 1.3 GPa. Relationship between the average grain size and the applied current density follows the Hall-Petch relationship well.

The authors demonstrate a high efficiency and high fidelity frequency beam splitter using coherent-state single photons and show how it can be used for operations or devices in long-distance quantum communication.

The Gram-negative bacterium Pseudomonas taiwanensis is a novel bacterium that uses shrimp shell waste as its sole sources of carbon and nitrogen. It is a versatile bacterium with potential for use in biological control, with activities including toxicity toward insects, fungi, and the rice pathogen Xanthomonas oryzae pv.oryzae (Xoo). In this study, the complete 5.08-Mb genome sequence of P. taiwanensis CMS was determined by a combination of NGS/Sanger sequencing and optical mapping. Comparison of optical maps of seven Pseudomonas species showed that P. taiwanensis is most closely related to P. putida KT 2400. We screened a total of 11,646 individual Tn5-transponson tagged strains to identify genes that are involved in the production and regulation of the iron-chelator pyoverdine in P. taiwanensis, which is a key anti-Xoo factor. Our results indicated that the two-component system (TCS) EnvZ/OmpR plays a positive regulatory role in the production of pyoverdine, whereas the sigma factor RpoS functions as a repressor. The knowledge of the molecular basis of the regulation of pyoverdine by P. taiwanensis provided herein will be useful for its development for use in biological control, including as an anti-Xoo agent.

The Gram-negative bacterium Pseudomonas taiwanensis is a novel bacterium that uses shrimp shell waste as its sole sources of carbon and nitrogen. It is a versatile bacterium with potential for use in biological control, with activities including toxicity toward insects, fungi, and the rice pathogen Xanthomonas oryzae pv.oryzae (Xoo). In this study, the complete 5.08-Mb genome sequence of P. taiwanensis CMS was determined by a combination of NGS/Sanger sequencing and optical mapping. Comparison of optical maps of seven Pseudomonas species showed that P. taiwanensis is most closely related to P. putida KT 2400. We screened a total of 11,646 individual Tn5-transponson tagged strains to identify genes that are involved in the production and regulation of the iron-chelator pyoverdine in P. taiwanensis, which is a key anti-Xoo factor. Our results indicated that the two-component system (TCS) EnvZ/OmpR plays a positive regulatory role in the production of pyoverdine, whereas the sigma factor RpoS functions as a repressor. The knowledge of the molecular basis of the regulation of pyoverdine by P. taiwanensis provided herein will be useful for its development for use in biological control, including as an anti-Xoo agent.

This paper develops a symmetric atmospheric plasma source integrated with electrospray ionization (ESI) tip as a dual-ion source for simultaneously detecting nonpolar and polar compounds using the ambient mass spectrometry. A cross-shaped tube with symmetric discharge electrodes is used to generate dielectric barrier discharge to produce ionized gas charging nonpolar molecules, while a coaxial capillary is placed at the center of the cross-shaped tube for generating electrospray discharge. Since there is no floating voltage at the outlet of the cross-shaped tube, the potential interference for the ESI can be excluded. Results show that dual-ion source can stably produce high-intensity ions of 109 ion $\cdot $ cm−3. Moreover, the relationship between the measured ion intensity and the gas flow rate, gas temperature, and applied voltage for ESI are systematically investigated. Various samples including volatile organic compounds, pesticides, Chinese herbal medicines, and vitamins are used for evaluating the sensing performance of the dual-ion source in plasma mode, electrospray mode, and dual-ion source mode, respectively. Results show that the developed dual source is efficient to simultaneously detect both the polar and nonpolar compounds.

Summary The Orchidaceae is a diverse and ecologically important plant family. Approximately 69% of all orchid species are epiphytes, which provide diverse microhabitats for many small animals and fungi in the canopy of tropical rainforests. Moreover, many orchids are of economic importance as food flavourings or ornamental plants. Phalaenopsis aphrodite, an epiphytic orchid, is a major breeding parent of many commercial orchid hybrids. We provide a high‐quality chromosome‐scale assembly of the P. aphrodite genome. The total length of all scaffolds is 1025.1 Mb, with N50 scaffold size of 19.7 Mb. A total of 28 902 protein‐coding genes were identified. We constructed an orchid genetic linkage map, and then anchored and ordered the genomic scaffolds along the linkage groups. We also established a high‐resolution pachytene karyotype of P. aphrodite and completed the assignment of linkage groups to the 19 chromosomes using fluorescence in situ hybridization. We identified an expansion in the epiphytic orchid lineage of FRS5‐like subclade associated with adaptations to the life in the canopy. Phylogenetic analysis further provides new insights into the orchid lineage‐specific duplications of MADS‐box genes, which might have contributed to the variation in labellum and pollinium morphology and its accessory structure. To our knowledge, this is the first orchid genome to be integrated with a SNP‐based genetic linkage map and validated by physical mapping. The genome and genetic map not only offer unprecedented resources for increasing breeding efficiency in horticultural orchids but also provide an important foundation for future studies in adaptation genomics of epiphytes.

Due to its low cost, environmentally friendly process, and lack of secondary contamination, the photodegradation of dyes is regarded as a promising technology for industrial wastewater treatment. This technology demonstrates the light-enhanced generation of charge carriers and reactive radicals that non-selectively degrade various organic dyes into water, CO2, and other organic compounds via direct photodegradation or a sensitization-mediated degradation process. The overall efficiency of the photocatalysis system is closely dependent upon operational parameters that govern the adsorption and photodegradation of dye molecules, including the initial dye concentration, pH of the solution, temperature of the reaction medium, and light intensity. Additionally, the charge-carrier properties of the photocatalyst strongly affect the generation of reactive species in the heterogeneous photodegradation and thereby dictate the photodegradation efficiency. Herein, this comprehensive review discusses the pseudo kinetics and mechanisms of the photodegradation reactions. The operational factors affecting the photodegradation of either cationic or anionic dye molecules, as well as the charge-carrier properties of the photocatalyst, are also fully explored. By further analyzing past works to clarify key active species for photodegradation reactions and optimal conditions, this review provides helpful guidelines that can be applied to foster the development of efficient photodegradation systems.

In this study, an electroless deposition method including catalyzation in supercritical carbon dioxide (sc-CO2) and plating in sc-CO2 emulsified electrolyte was applied in metallization of Nylon 6,6 textile. In order to demonstrate the effects of the sc-CO2, the catalyzation was conducted either by the conventional method or the supercritical CO2 catalyzation (SCC) method with bis (2,4-pentandionato)-palladium. After the catalyzation process, either the conventional electroless plating or the electroless plating with supercritical CO2 emulsified electrolyte (ELP-SCE) was performed. Surface of the Ni-P coatings on the Nylon 6,6 was observed by an optical microscope and a scanning electron microscope. The Ni-P coating by the conventional catalyzation and the conventional electroless plating showed some cracks, nodules and rough structure. The Ni-P coating by the SCC and the conventional electroless plating showed smooth Ni-P coating on the surface of each fibers and had some peeled-off parts. On the other hand, uniform Ni-P coating on the surface of each fibers was obtained by the SCC and the ELP-SCE. These results demonstrated that the SCC is effective to impregnate Pd catalysts into the fibers, and the ELP-SCE can inhibit the nodule growth of the Ni-P. Thus, the proposed method can metallize the surface of each Nylon 6,6 fibers and has potential to give some functions on textiles.

This study reports the effect of the high pressure on properties, especially the crystallinity, of the TiO 2 and SnO 2 films cathodically deposited in supercritical CO 2 emulsified electrolyte. The as-deposited metal oxides are usually amorphous when cathodic deposition is applied. An additional heat treatment process is needed to have crystalline metal oxides. In this study, the TiO 2 and SnO 2 thin films cathodically deposited at elevated pressure showed an improvement in the crystallinity with an increase in the pressure using X-ray diffraction analysis. The high-resolution transmission electron microscopy and selected-area electron diffraction confirmed that the TiO 2 deposited at 35 MPa had the anatase crystal structure. An enhancement in the charge carrier dynamics at the TiO 2 electrode/electrolyte interface with an increase in the pressure was observed from the electrochemical impedance spectroscopy, which is a result of the improved crystallinity. The effect of the pressure on the crystallinity of the SnO 2 was more obvious than that on the TiO 2 . Grain size of the SnO 2 films estimated by the Scherrer equation was increased from 3.5 to 14.8 nm when the pressure was increased from 5 to 25 MPa.

In this study, an electroless plating method involved Pt catalyzation in supercritical carbon dioxide (sc-CO2) and conventional Pt electroless plating was used for the metallization of polyamide 6,6 (PA66) textiles. The catalyzation was conducted either by conventional method at atmospheric pressure or in sc-CO2 with bis (2,4-pentandionato)-platinum. After the catalyzation process, the conventional Pt electroless plating method was performed for the Pt catalyzed PA66 textiles. Surface of the Pt coated PA66 was observed by an optical microscope and a scanning electron microscope. The Pt coating by the conventional catalyzation had a rough surface, and the surface did not show the textile outline because of the dissolution of the textile in the conventional catalyzation solution. The textile metallized by the sc-CO2 catalyzation showed a metallic bright coating, and the Pt coating was observed on the surface of each fiber. These results indicate that the sc-CO2 catalyzation is a promising method to catalyze the PA66 textile. Display Omitted Metallization of polyamide 66 (PA66) using supercritical CO2 (sc-CO2) was reported.Pt was used as the catalyst and coating to improve the biocompatibility.Pt catalyst seeds were formed by sc-CO2 catalyzation (SCC).Uniform Pt coating was formed by SCC follow by conventional electroless plating.The Pt coating was bright, defect-free and still showed outline of the PA66 fibers.

Micro-pillars oriented in austenite along [100], [110], and [111] crystallographic directions were fabricated on the corresponding edges of a single crystalline plate of the Ni48Fe20Co5Ga27 magnetic shape memory alloy exhibiting martensitic transformation (MT) at 150 K. Superelastic behavior of pillars, due to micro-compression-induced MT, was investigated at different temperatures from 298 K to 373 K. At room temperature, Young's moduli of the [100], [110], and [111] pillars in austenite are equal to 5.3 GPa, 7.9 GPa, and 9.9 GPa, respectively, resulting in the linear dependences of the elastic strain reaching up to the record-breaking value of 10%. On increasing temperature, the stress-strain dependencies exhibit changes that are interpreted in terms of the critical behavior on approaching to the end points on the martensite-austenite stress-temperature phase diagrams. This work was supported by JST CREST, Grant No. JPMJCR1433, Japan, and the Grant-in-Aid for Scientific Research (S) (JSPS KAKENHI Grant No. 26220907), as well as by Spanish Ministry of Science, Innovations and Universities (Project No. RTI2018-094683-B-C53-54) and by the Basque Government Department of Education (Project No. IT1245-19). Editorial

In recent years, MEMS (microelectromechanical systems) devices are required to have high functionality and small size, especially for MEMS acceleration sensors, and sensitivity of a MEMS acceleration sensor is highly dependent on the Brownian noise [1,2]. The Brown noise is known to be inversely proportional to mass of movable parts in the sensor, and the noise is lowered by increasing the mass [1,2], which implies a number of volume is needed to ensure high sensitivity. However, increasing size of the component is not preferable. Because of this, a design of gold-based MEMS acceleration sensor is proposed. The density of gold is 19.3 g/cm3, and gold has high corrosion resistance and chemical stability. Most importantly, gold electrodeposition process can be easily integrated with current MEMS fabrication process. Mechanical properties of the material are essential informtion for design of MEMS components. For instance, the yield stress is needed to guarantee elastic deformation of the material during operation of the MEMS device. Mechanical properties of metallic materials are known to change with size of the sample used in a mechanical property characterization becomes smaller than micrometer scale, which is known as the sample size effect [3]. Therefore, mechanical property characterization of materials toward MEMS should be conducted using samples having the same dimensions as those used in MEMS. Various micro-mechanical testing methods have been developed to characterize micro-specimens, such as micro-compression test, micro-tensile test, and micro-bending test. Among them, micro-bending test is suggested to be the most suitable method to evaluate materials for applications in MEMS when compared with micro-compression and micro-tensile tests since cantilever-like structure is commonly utilized in movable components, such as the micro-spring in MEMS accelerometers. On the other hand, micro-cantilevers are reported to have the sample geometry effect [4], which the sample size effect is only observed when varying thickness of the micro-cantilever. Also, it has been reported that the sample size effect is dependent on ratio of the sample diameter to the average grain size, and materials prepared by electrodeposition are usually polycrystal. Thus, relationship between the sample geometry effect and the average grain size is investigated in this study. Two gold films were electrodeposited at different current density to change the average grain size. The average grain size was determined by electron backscatter diffraction, and the average grain size of film A and B were 1.2~1.3 and 0.6 μm, respectively. Samples used in the micro-bending test were micro-cantilevers fabricated from the gold films by focus ion beam. Thicknesses of the micro-cantilever were ranged from 6.0 to 13 μm. The micro-bending tests are conducted using a test machine specially designed for micro-specimens developed in our group as shown in Fig. 1. The yield stresses were in a range of 428 to 553MPa, which were all higher than that of the bulk gold (55 to 220 MPa). Table 1 shows the detailed dimensions and yield stress of all samples. Yield stresses were plotted against the log scale of thickness shown in Fig. 2. At first, the sample geometry effect was confirmed in samples fabricated from both film A and B. Then, the yield stresses of samples fabricated from film B were all higher than those of film A, which was a result of the Hall-Petch relationship. In Fig. 2, the slop was steeper for film A indicating the sample geometry effect was more obvious in samples composed of larger grains. [1] D. Yamane, T. Konishi, T. Matsushima, K. Machida, H. Toshiyoshi, and K. Masu, Appl Phys Lett 104 (2014) 074102 [2] K. Machida, T. Konishi, D. Yamane, H. Toshiyoshi, K. Masu, ECS Trans. 61 (2014) 21-39. [3] J.R. Greer and J.Th.M. De Hosson: Plasticity in small-sized metallic systems: Intrinsic versus extrinsic size effect. Prog. Mater. Sci. 56, 654 (2011). [4] K. Suzuki, “Sample Geometry Effect on Mechanical Property of Electrodeposited Gold Evaluated by Micro-Bending Test", 45th International Conference on Micro & Nano Engineering (MNE2019), Rhodes Greece, Sep. 2019 Figure 1

Nickel [1], cobalt [2], and their alloys have been investigated as important engineering materials because of their unique properties, such as magnetic, heat-conductive and high hardness. Much interest is focused on the application of Ni-Co alloy films in micro-electrical-mechanical systems (MEMS) devices especially their considerable potential in manufacturing of magnetic actuator due to excellent electrical and mechanical properties [3]. Reliability of electronic components is highly dependent on the mechanical property, which is closely related to its average grain size according to grain boundary strengthening mechanism [4]. Nanocrystalline materials can offer enhanced mechanical strength compared with coarse-grained counterparts when device components are scaled to the micro-scale regime with synergistic effect of the sample size effect [5]. Meanwhile, alloying allows utilization of the solid solution strengthening mechanism to further enhance the mechanical strength [6], and Ni-Co forms a solid solution over the whole concentration range, making it easy to control the mechanical and magnetic properties. Electroplating is a promising technique in controlling crystalline properties of Ni-Co alloy films because the morphology, composition, grain size, and deposition rate of the deposited materials can be facilely controlled by varying the electroplating parameters, such as the current density, bath composition, and temperature [7]. Therefore, in this study, the effects of applied current density on average grain size, composition, and micro-mechanical properties of electrodeposited Ni-Co films are evaluated for fabrication of micro-components in electronic devices. The electroplating was carried out at 55 ℃, and the current density was varied from 5 to 20 mA/cm2. A piece of Pt plate was used as the anode. Crystalline structure of the Ni-Co films was characterized by X-ray diffraction (XRD), average grain size was determined using XRD in conjunction with the Scherrer method. Microhardness tests were conducted on a Vicker's hardness tester using a load of 0.025 kg, applied for 15 s. Composition was analysed by energy dispersive X-ray spectroscopy (EDX) system. Furthermore, alloy films are processed into micro-pillars in a size of 10×10×20 μm3with focused ion beam (FIB, FB2100, Hitachi) milling. The optical microscope photograph of Ni-Co alloy micro-pillar fabricated with current density of 18 mA/cm2 is shown in Fig. 1. A high yield stress of 1.65 GPa is determined after the micro-compression test. Vickers hardness as a function of d -1/2 for the alloy specimens is shown in the scatter plot of Fig. 2, where d is average grain size. Microhardness value has a positive linear relationship with d -1/2 approximately, which corresponds well to Hall-Petch relationship. Maximum Vicker's hardness value of 526 Hv was obtained with a current density of 10 mA/cm2, which is much higher than those of pure Ni (306 Hv) and Co (403 Hv) films prepared in this study, indicating the effect of solid solution strengthening. [1] T. Yamamoto, K. Igawa, H.C. Tang, C.Y. Chen, T.F.M. Chang, T. Nagoshi, O. Kudo, R. Maeda, M. Sone, Microelectron. Eng. , 213, 18 (2019). [2] X. Luo, C.Y. Chen, T.F.M. Chang, H. Hosoda, M. Sone, J. Electrochem. Soc. , 162, D423 (2015). [3] M. Duch, J. Esteve, E. Gómez, R. Pérez-Castillejos, E. Vallés, J. Micromech. Microeng. , 12, 400 (2002). [4] C.Y. Chen, M. Yoshiba, T. Nagoshi, T.F.M. Chang, D. Yamane, K. Machida, K. Masu, M. Sone, Electrochem. Commun. , 67, 51 (2016). [5] M. D. Uchic, D. M. Dimiduk, J. N. Florando, W. D. Nix, Sc ience , 305, 986 (2004). [6] H. Tang, T.F.M. Chang, Y.W. Chai, C.Y. Chen, T. Nagoshi, D. Yamane, H. Ito, K. Machida, K. Masu, M. Sone, J. Electrochem. Soc. , 165, D58 (2018). [7] A. Bai, C.C. Hu, Electrochimica Acta , 47, 3447 (2002). Figure 1

This study reports mechanical properties of single-crystal pure gold toward for applications as movable components in micro-electrical-mechanical system (MEMS) inertial sensors requiring high sensitivity. Gold is commonly applied in electronic devices because of the excellent corrosion resistance, chemical stability, and conductivity. Recently, MEMS inertial sensors utilizing gold materials are reported to have low Brownian noise and high sensitivity while keeping the dimensions small by taking advantage of gold’s high mass density [1]. For design of electronic device, mechanical property characterization of the constituent material is essential. In general, mechanical strengths of metallic materials are governed by movement of the dislocation, and the dislocation movement is affected by the crystal orientation, grain boundaries, texture, impurities, etc. In addition to these, mechanical properties of metallic materials are affected by size of the sample used in the evaluation when the sample size is reduced to micro or sub-micro scale, which is known as the sample size effect [2]. This sample size effect would cause mechanical properties of micro-scale metallic materials to differ from those of bulk-size materials. Therefore, in order to make contribution to design of MEMS devices, the mechanical property characterization must be conducted using specimens having dimensions and deformation system alike components used in MEMS. Micro-bending test is suggested to be the most suitable micro-mechanical property characterization method toward MEMS devices since movable components in a MEMS device would experience both compressive and tensile stresses during operation. Regarding the sample size effect, the strength has a power-law relationship with cross-sectional area of the specimen [2]. In bending test, the loading direction is perpendicular to the cantilever’s width direction and parallel to the thickness direction. Because of this, the width and the thickness are expected to affect the sample size effect differently. On the other hand, the dislocation movable is also highly affected by the grain boundary and eventually the sample size effect [3]. Hence, single crystalline specimen is often used to examine the sample size effect to eliminate influences from the grain boundary. In this study, micro-cantilevers composed of single-crystal pure gold were fabricated using focus ion beam (FIB). All micro-cantilevers were ensured to have the loading direction parallel to the [1-10] orientation and the neutral plane parallel to the [110] orientation. Lengths of the micro-cantilevers were fixed at 50 μm. The thicknesses and widths were varied between 5 to 15 μm. The bending test was performed using a machine specially designed for micro-specimens developed in our group as shown in Fig. 1. The strain rate was fixed at 0.125 %/sec. Fig. 2 shows scanning electron microscope (SEM) images of the 50×9.7×10.5 μm3 micro-cantilever before and after the micro-bending test. From these images, slip lines and necking were observed at the base of the cantilever where stress and deformation were concentrated after the bending test. This slip lines indicated the active slip plane according to the Schmid’s law. The engineering stresses, σ, were calculated utilizing the Euler-Bernoulli beam theory [4]. The engineering strains are calculated from ratio of the d/y [5], where d is displacement of tip of the indenter. Fig. 3 shows engineering stress-engineering strain curves of the five micro-cantilevers. Yield stresses of the 6.9, 10.5, and 15.1 μm thick micro-cantilevers were 195, 175, and 128 MPa, respectively. Yield stress of the 4.7, 9.7, and 15.1μm width micro-cantilevers were 177, 175, and 183 MPa, respectively. These yield stresses were all lager than the value of bulk-size pure gold, which were results of the sample size effect. In addition, the yield stress increased as the thickness decreased, whereas it does not change much with the width reduction. This result suggested the sample size effect was only observed when changing the thickness, but not the width. These findings confirmed mechanical properties of micro-cantilevers were affected by the sample geometry, which is named as the sample geometry effect. [1] D. Yamane, T. Konishi, T. Matsushima, K. Machida, H. Toshiyoshi, and K. Masu, Appl. Phys. Lett. 104 (2014) 074102 [2] J.R. Greer, W.C. Oliver, W.D. Nix, Acta. Mater. 53 (2005) 1821-1830. [3] J.R. Greer and J.Th.M. De Hosson, Prog. Mater. Sci. 56 (2011) 654-724 (2011). [4] K. Asano, T.F.M. Chang, H.C. Tang, T. Nagoshi, C.Y. Chen, D. Yamane, H. Ito, K. Machida, K. Masu, M. Sone, ECS J. Solid State Sci. Technol., 8 (2019) P412-P415. [5] E. Demir, D. Raabe, F. Roters, Acta. Mater. 58 (2010) 1876-1886. Figure 1

In this study, we design a Cassegrain-based concentrator with tailored mirrors. The proposed concentrator comprises a primary optical element (POE) and a secondary optical element (SOE). The POE is a parabolic concave mirror and the SOE is a hyperbolic convex mirror. In order to achieve uniform irradiance distribution without a homogenizer, the POE is tailored and tilted to generate a uniform distribution by overlapping the energy well. The Cassegrain-based concentrator with tailored mirrors can achieve a geometric concentration ratio of 1236 × , a concentration ratio of 1034 × , an optical efficiency of 83.66%, an acceptance angle of ± 0.38 ∘ , a uniformity of 7.87, and an aspect ratio of 0.254.

Electrodeposited gold is used in movable micro-components of micro-electro-mechanical systems (MEMS) devices to allow further enhancement in the sensitivity and miniaturization of the device [1]. Mechanical strengths of gold are low among materials commonly used as structure materials in electronic devices. Electrodeposition method is advantageous in strengthening metallic materials because of the ability to refine the average grain size to nano-scale, which the mechanical strength increases along with a reduction in the grain size based on the grain boundary strengthening mechanism or the Hall-Petch relationship. Alloying of metallic materials is also an effective strategy to achieve the strengthening according to the solid solution strengthening mechanism. On the other hand, mechanical properties of metallic materials exhibit the sample size effect when dimensions of the specimen are reduced to micro or sub-micro scale. Therefore, mechanical property characterization of materials for MEMS applications should be conducted using specimens having dimensions in micro-scale. Various micro-mechanical testing methods have been developed in our group to characterize micro-specimens, such as micro-compression test [2,3], micro-tensile test [4], and micro-bending test [5]. Among them, micro-bending test is suggested to be the most suitable method to evaluate materials for applications in MEMS when compared with micro-compression and micro-tensile tests since cantilever-like structures are often applied in MEMS components, such as the micro-spring in a MEMS accelerometer. In this study, Au-Cu alloys are prepared by electrodeposition, and micro-mechanical properties of the electrodeposited Au-Cu alloys are characterized by a micro-bending test. Young’s modulus is an important information in design of movable micro-components. A non-destructive Young’s modulus evaluation method, resonance frequency measurement, is conducted using the Au-Cu alloy micro-cantilevers. Also, long-term vibration tests are conducted to reveal structure stability of the Au-Cu alloy micro-cantilevers. The Au-Cu electrolyte used in this work was a commercially available electrolyte provided by MATEX Co. Japan, which contained 17.3 g/L of X3Au(SO3)2 (X = Na, K), 1.26 g/L of CuSO4, and ethylenediaminetetraacetic acid as the additive with pH at 7.5. The electrodeposition was carried out at 50 °C, and the current density was varied from 0.1 to 8 mA/cm2. Specimens used in the micro-bending test were micro-cantilevers fabricated from the Au-Cu alloy films by focused ion beam. Dimensions of the micro-cantilevers fabricated were 10 µm × 10 µm × 50 µm. The micro-bending tests were conducted using a test machine equipped with a spherical diamond indenter at a constant displacement rate of 0.05 µm/s. For the Young’s modulus and long-term structure stability evaluations, the micro-cantilevers were prepared by electrodeposition combined with lithography process. The long-term vibration test was carried out under conditions of the cycle number in a range from 103 to 106, the frequency of 10.0 Hz, and the acceleration of 1.0 G (1 G = 9.8 m/s2). The structure stability was determined by evaluating height profiles of top surface of the micro-cantilevers before and after the vibration test by a 3D optical microscope. The Au-Cu alloy film electrodeposited at 5 mA/cm2 had the finest average grain size among films prepared in this work, which the grain size was 4.76 nm. Bending test of a micro-cantilever prepared from this film shows a high yield stress at 1826 MPa. Gold, copper, and Au-Cu alloys are known to be ductile materials, but brittle fracture was observed during the bending test when the current density used in prepared the film was higher than 5 mA/cm2. From the resonance frequency method, Young’s moduli of the Au-Cu alloy micro-cantilevers were ranged from 68.0 to 79.5 GPa, which were similar to the value of bulk-size specimens and indicated no sample size effect on the Young’s modulus. Regarding the long-term structure stability, after 106 cycles of the vibration test, all the micro-cantilever were still intact, and the height profiles did not change much after the vibration. Results obtained in this study confirmed high mechanical strength and structure stability in the electroplated Au-Cu alloys and demonstrated the advantage in applications as movable components in MEMS devices. [1] D. Yamane et. al. Appl. Phys. Lett. 104 (2014) 074102. [2] C.Y. Chen et. al. Electrochem. Commun. 51 (2016) 51-54. [3] H. Tang et. al. J. Electrochem. Soc. 164 (2017) 244-247 [4] Y. Kihara et. al. Mater. Lett. 153 (2015) 36-39 [5] K. Asano et. al. ECS J. Solid State Sci. Technol. 8 (2019) P412-P415.

This study reports the metallization of polyimide films with enlarged area by conducting the catalyzation step in supercritical CO 2 . Defect-free Ni coating with high adhesion strength on the polyimide film having dimensions of 12.0 × 4.5 cm 2 was realized using a high pressure vessel with diameter and height of only 4.0 and 4.5 cm, respectively. The ability to conduct the catalyzation of polyimide films having a size larger than size of the reaction cell is a result of the enhanced transport properties caused by the supercritical CO 2 . With 8 min of plating time, the Ni coating thickness on the polyimide film reached 1.077 μm, and the resistivity and adhesion strength were 1.4 Ω and 1.5 MPa, respectively.

Novel three-dimensional hierarchical heterostructures composed of two-dimensional SnS 2 nanoflakes and zero-dimensional SnO 2 nanoparticles were fabricated via a one-step hydrothermal method. Size of the heterostructures was ca. 2 μm in diameter, and individual SnS 2 nanoflakes with thickness of ca. 150 nm were connected to central core of the heterostructures. The SnO 2 nanoparticles in a diameter of ca. 5 nm uniformly covered entire surface of the SnS 2 nanoflakes. Moreover, both of these structures were highly crystalline. Meanwhile, amorphous carbon was formed within the heterostructures. The SnS 2 /SnO 2 /C hierarchical heterostructures had a high initial specific reversible capacity of 1065.7 mAh g −1 , stable cycling stability of 638 mAh g −1 after 30 cycles, and superior rate capability of 550.8 mAh g −1 at 1C rate. These SnS 2 /SnO 2 /C hierarchical heterostructures showed better performance than individual SnS 2 and SnO 2 nanomaterials, and the performance was even higher than the graphene–SnS 2 and graphene–SnO 2 nanohybrid materials. This is attributed to a synergistic effect of high surface area, which is provided by the unique SnS 2 internal nanoflake layered structures decorated with ultra-fine SnO 2 nanoparticles, and an effective beneficial buffer matrix to accommodate the large volume change upon cycling, which is caused by the side-products such as Li 2 S or Li 2 O. The SnS 2 nanoflake was deduced to play a similar role as graphene material, since both possess 2D conducting layer structures. The uniform carbon dispersion within the structures also stabilizes the structures and improves electrical conductivity of the hierarchical heterostructures.

This paper develops a novel symmetric dielectric barrier discharge (DBD) plasma as an ion source for environmental mass spectrometry (MS) applications. The conventional linear-type DBD plasma generator suffers the drawback of floating voltage at the plasma outlet. This paper develops an innovative symmetric T-shaped DBD plasma generator to produce atmospheric plasma with zero-floating potential for high-sensitivity MS analysis. By changing the geometric configuration and the drive phase of the symmetric T-shaped DBD plasma generator, the resulting symmetric structural design can fully cancel the floating potential and noise signal. Therefore, the main objective of this paper is to compare the differences between traditional linear-type DBD and the symmetric T-shaped DBD designs using MS, spectroscopy, and some basic electrical measurements. The most suitable parameters are determined by changing the electrode design, voltage, temperature, gas flow rate, diameter, and other parameters of the plasma tube. The symmetric T-shaped design generator produces the zero-potential plasma that generates fewer ambient gas molecules to form ozone, NOx, water clusters, and other strong oxidizing molecules such that less damage to the MS samples occurs. This in turn results in a less fragmented ion signal and higher sensing performance for rapid MS applications. In addition, the proposed system can directly ionize gas, liquid, and solid samples at more than $10^{7}$ -cm$^{-3}$ ion concentration. Results show that more information-rich spectra can be obtained with the developed symmetric T-shaped DBD plasma generator compared with the typical linear-type DBD generator.

Sn/SnO2 composite materials are promising anode materials in lithium ion battery. Electrodeposition with supercritical CO2(sc-CO2) emulsified electrolyte (EP-SCE) is an effective method in controlling morphology (Ni [1], Cu[2], and Co[3]) and crystallinity (ZnO [4]and TiO2 [5]) of electrodeposited materials. Sc-CO2 is CO2 at temperature and pressure above its critical point, which is 304.1 K and 7.38 MPa. CO2 is non-polar, therefore, the solubility of metal salts and electrical conductivity are both very low in sc-CO2. In order to conduct electrochemical reactions, surfactants are used to form emulsified electrolyte. Co-deposition of SnO2 along with electrodeposition of metallic Sn can occur at the same time in a SnCl2 based electrolyte containing NO3 - ions [6]. The EP-SCE is expected to be effective in controlling concentration and properties of the SnO2 in metallic Sn film. In this study, Sn/SnO2 composite films are prepared by electrodeposition with supercritical CO2 (sc-CO2) emulsified electrolyte, and the mechanical properties in micro-scale are evaluated by compression test of micro-pilliars fabricated from the Sn/SnO2 composite film for practical applications. Details of the high pressure electrochemical apparatus can be found in a previous study [1]. The electrolyte is composed of 0.22 M SnCl2, 0.015 M HCl and 0.31 M (NH4)3C6H5O7. The current density applied is varied from 2.8 to 17.3 mA/cm2. For the EP-SCE, the surfactant is C12H25(OCH2CH2)15OH. 0.2 vol.% of the surfactant is used to form the sc-CO2 emulsions. 20 vol.% of CO2 at 343 K and 15 MPa under agitation are used to ensure the formation of a stable emulsion. Electrodeposition without the sc-CO2 emulsions at ambient condition (CONV) was also conducted to be used as a comparison. Surface morphology of the films prepared by EP-SCE were very smooth and compact, and the CONV films were porous. On the other hand, there is not much different in the average grain size between the EP-SCE and CONV films, which was about 50 μm for both the EP-SCE and CONV films. The oxygen content in the EP-SCE films can be up to 28.3 at.% by adjusting the electrodeposition parameters. Micro-pillars with a 20×20 μm2 cross-section and a height at 40 μm were fabricated by focus ion beam from the deposited films. The yield stresses were ranged from 10 to 40 MPa when the current density changed. Acknowledgment: This work was supported by JST CREST Grant Number JPMJCR1433. Reference: [1] Electrochim. Acta 55 (2010) 6469-6475 [2] Thin Solid Films 529 (2013) 25-28 [3] J. Electrochem. Soc. 162 (2015) D423-D426 [4] J. Phys. Chem. C 117 (2013) 25596-25603 [5] Electrochem. Commun. 33 (2013) 68-71 [6] J. Alloys Compd. 403 (2005) 335-340

TiO2 thin films were fabricated by cathodic deposition with a supercritical CO2 (sc-CO2) emulsified TiCl3 + NaNO3 electrolyte. Morphology and average grain size were evaluated by SEM, TEM and XRD. SEM micrographs showed that the TiO2 films fabricated by TiCl3 + NaNO3 electrolyte were porous, and the films were composed of particles and aggregates of the particles. Also, size of the particles increased when the sc-CO2 emulsified electrolyte was used. Average grain size of the TiO2 films was calculated using Scherrer equation. The average grain size was found to increase when the sc-CO2 emulsified electrolyte was used. In addition, both particle sizes observed from SEM and average grain size calculated using Scherrer equation were found to increase when pressure was increased from atmospheric pressure to 20 MPa. Keywords: TiO2, Cathodic deposition, Supercritical CO2, Morphology, Grain size

This study reports structure stability of micro-cantilevers composed of Au-Cu alloy for applications as moveable components in micro-electrical-mechanical system (MEMS) accelerometers. Au-based micro-components are developed to replace conventional Si-based components in a MEMS accelerometer to allow further miniaturization of the device [1]. However, the mechanical strength of Au is relatively low when compared with that of Si. The low mechanical strength raises concerns on structure stability of movable micro-components composed of Au-based materials, which could affect reliability and lifetime of the device. Electroplating is a promising technique in manipulating properties of the metallic materials for applications in MEMS. For instance, grain refinement effect often observed in electroplating can be employed to enhance the mechanical strength by the grain boundary strengthening mechanism [2]. In addition, alloy electroplating is a fascinating technique capable of controlling composition of the metallic material, and alloying the metallic material allows utilization of the solid solution strengthening mechanism to further enhance the mechanical strength [3]. By synergistic effects of the grain boundary strengthening and solid solution strengthening mechanisms, an ultra-high yield stress of 1.15 GPa [3] is reported for electroplated Au-Cu micro-specimens, which is comparable to fracture strength of Si. In order to apply the high-strength Au-Cu alloy as movable structures in MEMS devices, investigating the vibration fatigue is necessary to confirm the reliability and the lifetime. In this study, long-term vibration tests of micro-cantilevers fabricated by combining lithography and Au-Cu alloy electroplating were conducted to reveal effects of the vibration fatigue on structure stability of the Au-Cu alloy micro-cantilevers. Fabrication process of the micro-cantilevers is illustrated in Fig. 1. The Ti barrier layer and the Au seed layer were deposited by sputtering, and the layer thicknesses were both at 100 nm. The Au–Cu electrolyte used in this work was a commercially available electrolyte provided by MATEX Co. Japan, which contained 17.3 g/L of X3Au(SO3)2 (X = Na, K), 1.26 g/L of CuSO4, and ethylenediaminetetraacetic acid as the additive with pH at 7.5. The electroplating was carried out at 50 ◦C, and the current density was varied from 0.1 to 3 mA/cm2. A piece of Pt plate was used as the anode. Image of the Au-Cu alloy micro-cantilevers before the vibration test is shown in Fig. 2. Design-length of the micro-cantilever (l) was varied from 50 ~ 1000 μm, and design-width of the micro-cantilever (w) was ranged from 5 ~ 20 μm. Thickness of the Au-Cu alloy layer (t) was from 2.3 ~ 5.0 μm. The long-term vibration test was carried out under conditions of the cycle number in a range from 103 to 106, the frequency of 10.0 Hz, and the acceleration of 1.0 G (1 G = 9.8 m/s2). The structure stability was determined by evaluating height profiles of top surface of the micro-cantilevers before and after the vibration test by a 3D optical microscope. Height profiles of a micro-cantilever composed of 97.7 % Au with the length at 1000 μm, the width 20 μm, and the thickness at 3.9 μm before and after the vibration test are shown in Fig. 3. Fluctuations in the height before the vibration test, the 0 cycle result, were mainly results of the surface roughness. After 106 cycles of the vibration test, the micro-cantilever was still intact as observed from the optical microscope. The height profiles did not change much after the vibration. In order to quantify the structure stability, deflection at tip of the micro-cantilever was determined. The tip deflection merely changed 0.37 μm for the 1000 μm long micro-cantilever after 106 cycles of the vibration test. This result confirmed high structure stability in the electroplated Au-Cu alloy micro-cantilever and demonstrated the superiority of this Au-Cu alloy structure in applications as movable components in MEMS devices. [1] D. Yamane, T. Konishi, T. Matsushima, K. Machida, H. Toshiyoshi, K. Masu, Appl. Phys. Lett., 104 (2014) 074102. [2] H. Tang, C.-Y. Chen, T. Nagoshi, T.-F.M. Chang, D. Yamane, K. Machida, K. Masu, M. Sone, Electrochem. Commun., 72 (2016) 123–130. [3] H. Tang, C.-Y. Chen, M.Yoshiba, T.Nagoshi, T.-F.M. Chang, D.Yamane, K.Machida, K.Masu, M.Sone, Electrochemical Society, 164 (2017) 244–247 Figure 1

The coordinating properties of N - o -chlorobenzamido- meso -tetraphenylporphyrin ( N -NHCO( o -Cl)C 6 H 4 -Htpp; 11 ) have been investigated for the Zn 2+ ion. Insertion of Zn results in the formation of the zinc complex Zn( N -NCO( o -Cl)C 6 H 4 -tpp)(MeOH) · MeOH ( 12 · MeOH). The diamagnetic 12 · MeOH can be transformed into the diamagnetic Zn( N -NHCO( o -Cl)C 6 H 4 -tpp)Cl · CH 2 Cl 2 ( 13 · CH 2 Cl 2 ) in a reaction with aqueous hydrogen chloride (2%). X-ray structures for 12 · MeOH and 13 · CH 2 Cl 2 have been determined. The coordination sphere around the Zn 2+ ion in 12 · MeOH is a distorted trigonal bipyramid with N(2), N(4) and O(2) lying in the equatorial plane, whereas for the Zn 2+ ion in 13 · CH 2 Cl 2 , it is a square-based pyramid in which the apical site is occupied by the Cl(1) atom.

Helicobacter pylori is an important risk factor of duodenal ulcer (DU). Although many virulence factors of H. pylori have been identified, few have been reported to show an association with the pathogenesis of DU. The aims of this study were to identify H. pylori antigens showing a high seropositivity in DU and to develop a platform for rapid and easy diagnosis for DU. Because DU and gastric cancer (GC) are considered clinical divergent gastroduodenal diseases, we compared two-dimensional immunoblots of an acid-glycine extract of an H. pylori strain from a patient with DU probed with serum samples from 10 patients with DU and 10 with GC to identify DU-related antigens. Of the 11 proteins that were strongly recognized by serum IgG from DU patients, translation elongation factor EF-G (FusA), catalase (KatA), and urease alpha subunit (UreA) were identified as DU-related antigens, showing a higher seropositivity in DU samples (n = 124) than in GC samples (n = 95) (FusA, 70.2 versus 45.3%; KatA, 50.8 versus 41.1%; UreA, 44.4 versus 27.4%). In addition, we found that the use of multiple antigens improved the discrimination between patients with DU and those with GC as the odds ratios increased from 1.82 (95% confidence interval (CI), 0.79-4.21; p = 0.1607) for seropositivity for FusA, KatA, or UreA alone to 4.95 (95% CI, 2.05-12.0; p = 0.0004) for two of the three antigens and to 5.71 (95% CI, 1.86-17.6; p = 0.0024) for all three antigens. Moreover a protein array containing the three DU-related antigens was developed to test the idea of using multiple biomarkers in diagnosis. We conclude that FusA, KatA, and UreA are DU-related antigens of H. pylori, and the combination of these on a protein array provided a rapid and convenient method for detecting serum antibody patterns of DU patients.

Background. Myofibroblastic conversion of mesothelial cells is proposed to play an important role in pathological changes following serosal membrane injury. Methods. Human peritoneal mesothelial cells (HPMCs) were isolated and maintained in culture. The gene expression was assessed by RT–PCR. Activation of signal transduction was determined by western blot and densitometry. Morphological changes were observed by phase-contrast and electron microscopy. Results. In vitro study showed that TGF-b1-induced myofibroblastic growth of HPMCs was significantly enhanced in the presence of leptin. Augmented expression of a-smooth muscle actin, fibronectin and type I collagen mRNA in HPMCs induced by leptin were TGF-b1-dependent, suggesting that leptin promoted peritoneal fibrogenesis through synergistic activation of the TGF-b1 signaling system. Leptin and TGF-b1 synergistically augmented activation of signalling components of mitogen-activated protein kinase (MAPK), STAT3 and Smad but did not modulate the expression of LEPR-B. Conclusion. Leptin may act as a profibrogenic TGF-b1 activated cytokine in peritoneal bioenvironment associated with TGF-b1 activated pathogenic processes.

The NAD(P)H dehydrogenase complex is encoded by 11 ndh genes in plant chloroplast (cp) genomes. However, ndh genes are truncated or deleted in some autotrophic Epidendroideae orchid cp genomes. To determine the evolutionary timing of the gene deletions and the genomic locations of the various ndh genes in orchids, the cp genomes of Vanilla planifolia, Paphiopedilum armeniacum, Paphiopedilum niveum, Cypripedium formosanum, Habenaria longidenticulata, Goodyera fumata and Masdevallia picturata were sequenced; these genomes represent Vanilloideae, Cypripedioideae, Orchidoideae and Epidendroideae subfamilies. Four orchid cp genome sequences were found to contain a complete set of ndh genes. In other genomes, ndh deletions did not correlate to known taxonomic or evolutionary relationships and deletions occurred independently after the orchid family split into different subfamilies. In orchids lacking cp encoded ndh genes, non cp localized ndh sequences were identified. In Erycina pusilla, at least 10 truncated ndh gene fragments were found transferred to the mitochondrial (mt) genome. The phenomenon of orchid ndh transfer to the mt genome existed in ndh-deleted orchids and also in ndh containing species.

Mobile data usage is on the rise globally. In emerging regions, mobile data is particularly expensive and suffers from the lack of price and data usage transparency needed to make informed decisions about Internet use. To measure and address this problem, we designed SmartBrowse, an Internet proxy system that shows mobile data usage information and provides controls to avoid overspending. In this paper, we discuss the results of a 10-week study with SmartBrowse, involving 299 participants in Ghana. Half the users were given SmartBrowse, and the other half was given a regular Internet experience. Our findings suggest that, compared with the control group, using SmartBrowse led to a significant reduction in Internet credit spend and increased online activity among SmartBrowse users, while providing the same or better mobile Internet user experience. Additionally, SmartBrowse users who were prior mobile data non-users increased their webpage views while spending less money than control users. Our discussion contributes to the understanding of how forward-looking ICTD research in the wild can empower mobile data users, in this case, through increased price transparency.

Previously we developed genomic resources for orchids, including transcriptomic analyses using next-generation sequencing techniques and construction of a web-based orchid genomic database. Here, we report a modified molecular model of flower development in the Orchidaceae based on functional analysis of gene expression profiles in Phalaenopsis aphrodite (a moth orchid) that revealed novel roles for the transcription factors involved in floral organ pattern formation. Phalaenopsis orchid floral organ-specific genes were identified by microarray analysis. Several critical transcription factors including AP3, PI, AP1 and AGL6, displayed distinct spatial distribution patterns. Phylogenetic analysis of orchid MADS box genes was conducted to infer the evolutionary relationship among floral organ-specific genes. The results suggest that gene duplication MADS box genes in orchid may have resulted in their gaining novel functions during evolution. Based on these analyses, a modified model of orchid flowering was proposed. Comparison of the expression profiles of flowers of a peloric mutant and wild-type Phalaenopsis orchid further identified genes associated with lip morphology and peloric effects. Large scale investigation of gene expression profiles revealed that homeotic genes from the ABCDE model of flower development classes A and B in the Phalaenopsis orchid have novel functions due to evolutionary diversification, and display differential expression patterns.

Au materials fabricated by electroplating are commonly used as contact materials for high reliability circuit boards, electrical connectors, relays, and micro- and nano-scale electronic components for many decades because of their high electrical conductivity, chemical stability, corrosion resistance, and ductility. In recent years, Au has become a promising material to be used as the movable structures and proof mass in micro-electrical-mechanical system (MEMS) accelerometer devices, mostly because of the high density (19.3×103 kg/m3 at 298 K), which is about 10 times higher than that of silicon (2.33×103 kg/m3at 298 K) [1]. However, Au is known to be a soft material. The mechanical strength becomes a concern in miniaturization of the MEMS device. Yield stress of bulk Au is reported to be 55~200 MPa [2]. Decreasing grain size of the Au materials is expected to further enhance the mechanical properties according to the Hall-Petch relationship [3]. Pulse electroplating (PE) has been reported to be effective in fabricating Au materials with fine grains, high uniformity, and low porosity [4]. Also, it is possible to control the composition and the film thickness by regulating the pulse amplitude and width. Most importantly, an increase in the nuclei density could be achieved to obtain electroplated films with finer grains. On the other hand, for evaluating mechanical properties of the electroplated films, Vickers micro-hardness test is the most popular method. However, the hardness results are often affected by the substrate. It cannot show the real strength of the electroplated materials, especially for films in mico-/nano-scale. Therefore, it is necessary to evaluate micro-mechanical strength of the Au electroplated films for the practical applications in the miniaturized devices. Au electrolyte used in this study was a commercially available sulfite-based electrolyte provided by Matex Japan (Matex Gold NCA). The electrolyte contains 50 g/L of Na2SO3, 50 g/L of (NH4)2SO3, and 21.63 g/L of Na3[Au(SO3)2] with pH of 8.0 and 5% sodium gluconate. Cu plates and Pt plates were used as the cathode and anode, respectively. For the PE, the pulse current (Ion) was 10 mA/cm2, and the off-time current (Ioff) was 0 mA/cm2. The on-time (Ton) of the PE varied from 1 to 100 ms, and the off-time (Toff) was 10 ms. The reaction temperature was 40 ºC for the gold electroplating. The Au films prepared by the PE showed less defect, lower surface roughness, finer grain size, and denser texture when compared with the Au films prepared by the conventional constant-current electroplating (CE). Micro-mechanical properties of Au micro-pillars fabricated from the Au films were evaluated by micro-compression test. Dimensions of the fabricated pillars were 10 μm×10 μm×20 μm. The compression tests were carried out using a test machine specially designed for micro-sized specimens equipped with a flat-ended diamond indenter at a constant displacement of 0.1μm/s. The Au micro-pillars prepared by the PE showed controllable high strength ranged from 500 to 800 MPa, where the grain size was adjusted by the PE parameters. Finest grain size was estimated to be 10.4 nm, and the highest compressive strength was 800 MPa [5]. The compressive strength obtained is much higher than the values reported in other studies [6,7]. The high strength is suggested to be due to the grain-boundary strengthening mechanism. The results demonstrated that the PE method and the sulfite-based electrolyte are promising for applications in miniaturization of the MEMS devices. To the best of our knowledge, this is the also first report on micro-mechanical strength of pure Au materials fabricated by the PE. References: [1] D. Yamane, T. Konishi, T. Matsushima, K.Machida, H. Toshiyoshi, K. Masu, Appl. Phys. Lett. 104 (2014) 074102. [2] H.D. Espinosa, B.C. Prorok, B. Peng, J. Mech. Phys. Solid 52 (2004) 667–689. [3] N. J. Petch, J. Iron Steel Inst. 174 (1953) 25–28. [4] J. Horkens, L. T. Romankiw, J. Electrochem. Soc. 124 (1977) 1499–1505. [5] C.Y. Chen, M. Yoshiba, T. Nagoshi, T.F.M. Chang, D. Yamane, K. Machida, K. Masu, M. Sone, Electrochem. Commun., 67 (2016) 51–54. [6] D. Jia, K.T. Ramesh, E. Ma, Acta Mater. 51 (2003) 3495–3509. [7] Z. Gan, Y. He, D. Liu, B. Zhang, L. Shen, Scripta Materialia 87 (2014) 41–44.

According to the International Data Corporation (IDC) report [1], the worldwide wearable devices market will swell to 111.9 million networked devices sold in 2018 projecting the trend and blossom of this potential technology. To fulfill both conductivity and flexibility for wearable device, combining the conductive materials and the flexible fabrics, such as metal and polymer, becomes the greatest challenge. There are many techniques to achieve the combination, such as sputtering and evaporation. Among these, electroless plating is the most potential method owing to its eminent advantages, e.g. low processing temperature, low cost, and simple operation procedures [2]. Electroless plating consists of a pretreatment step to clean and roughen the substrate, a catalyzation step to inlay the catalyst seeds, and a plating step to carry out the metallization on the substrate. A novel catalyzation step with the assist of supercritical carbon dioxide (sc-CO2) was conducted in this study. Distinct from the conventional catalyzation, catalyzing the polymer in sc-CO2 allows exclusion of the pretreatment step and further results a defect-free and smoother surface [3]. With the outstanding self-diffusivity, high compatibility with non-polar materials, and low surface tension characteristics of sc-CO2, organo-metallic catalysts can be embedded into the polymer without damaging the structure. Furthermore, with sc-CO2, the chemical solution used in the catalyzation step can also be withdrawn, which is friendlier to the environment. In previous studies, we have proposed an electroless plating method involving Ni-P plating step on polyimide followed by catalyzation in pure sc-CO2 containing Pd (II) acetylacetonate (Pd(acac)2) [3,4]. Ni-P solution is a common electrolyte for the plating due to the advantages, such as relatively high deposition rate and high corrosion resistivity. To obtain higher mobility and the application of wearable devices, softer silk is chosen as the substrate in this study. Moreover, silk is a common material in clothes. The combination of Ni-P and silk is thus considered to be a potential candidate for the wearable devices. This work, therefore, executed the electroless plating between Ni-P and silk. A piece of the silk textile was immersed in the sc-CO2 fluid containing Pd(acac)2 at 80 oC and 15 MPa. Appropriate amount of the Pd(acac)2 catalyst was used to maintain the concentration at the saturation concentration throughout the catalyzation step. No pretreatment was conducted in this study. The plating step was thereupon being carried out on the catalyzed silks at 70 oC and atmospheric pressure in the acidic Ni-P solution. Various lengths of plating times were performed to inspect the relationship between the plating time and the properties. The surface morphology, cross-section and composition were examined by an optical microscope (OM), scanning electron microscope (SEM), and energy dispersive X-ray spectroscopy (EDX). The phase and crystal structure were identified by an X-ray diffractometer (XRD). The electrical resistance was measured by the four-point probe method. By conducting the catalyzation in sc-CO2, smooth and uniform coverage of Ni-P coatings were successfully plated on the silk textiles under various plating times. The composition, thickness, and coverage trend increase with plating time. The composites turn out to be conductive as the plating time is extended to 2 mins. Lowest electrical resistance at 1.23 ohm can be achieved with plating time at 4 min. References [1] R.T. Llamas, Worldwide Wearable Computing Device 2014–2018 Forecast Update: December 2014, U.S.A.: IDC Research, Inc. (2014). [2] G.O. Mallory and J.B. Hajdu, "Electroless plating: fundamentals and applications", United Kingdom: Cambridge University Press, (1990). [3] B.H. Woo, M. Sone, A. Shibata, C. Ishiyama, K. Masuda, M. Yamagata, and Y. Higo, Microelectron. Eng. 86 (2009) 1179-1182. [4] B.H. Woo, M. Sone, A. Shibata, C. Ishiyama, K. Masuda, M. Yamagata, and Y. Higo, Surf . Coat . Techno ., 203 (2009) 1971-1978.