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This study investigated the accumulation of γ-aminobutyric acid (GABA) in mung bean sprouts (Vigna Radiata L.) during germination under hypoxia/anaerobic conditions. Raw mung bean seeds were soaked in water at 35oC for 8 hours, dried and germinated under aerobic or hypoxia/anaerobic conditions at 35oC or 40oC for 0, 6, 12, 24, 36 and 48 hours. Free amino acid and GABA contents were measured during the course of germination. Effect of soaking pH (5.3, 6.3 and 7.3) on GABA content of germinated mung beans under hypoxia/anaerobic condition was also investigated. The other objective of this study was to optimize the culture conditions of GABA production in germinated mung bean. A significant increase (p < 0.05) of GABA content was found in mung bean samples germinated under hypoxia/anaerobic condition. As this result, the combination of soaking pH 6.3 and 12 hour germination at 35oC was found to yield the highest GABA content (1519.07±19.58ppm). This figure was 1.41 times as high as the content in aerobic condition and 25.32 times as high as the analysis of the raw mung beans. And experimental analysis showed that the optimal condition with aeration treatment for GABA accumulation in germinated mung bean was at a temperature of 36.6oC, time of 14.5 h and a pH value of 5.83; the highest GABA yield was 1638.67ppm, which was 27.77 times higher than raw seeds. In conclusion, germinated mung bean is a good source of GABA and hypoxia/anaerobic condition in combination with soaking pH, germination time and temperature can increase significantly GABA content in germinated mung beans.

Hematite nanoflake arrays were decorated with Au nanoparticles through a simple solution chemistry approach. We show that the photoactivity of Au-decorated Fe2 O3 electrodes for photoelectrochemical water oxidation can be effectively enhanced in the UV/Visible region compared with the bare Fe2 O3 . Au-nanoparticle-decorated Fe2 O3 nanoflake electrodes exhibit a significant cathodic shift of the onset potential up to 0.6 V [vs. reversible hydrogen electrode (RHE)], and a two times increase in the water oxidation photocurrent is achieved at 1.23 VRHE . A maximum photocurrent of 2.0 mA cm(-2) at 1.6 VRHE is obtained in 1 M KOH under AM 1.5 (100 mW cm(-2) ) conditions. The enhancement in photocurrent can be attributed to the Au nanoparticles acting as plasmonic photosensitizers that increase the optical absorption.

In the present work we introduce a technique to form a photocatalyst based on Pt nanoparticles suspended over the mouth of anodic TiO2 nanotubes. These structures are obtained by decorating the top end of highly ordered TiO2 nanotubes with a web of TiO2 nanofibrils, followed by sputter deposition of a minimum amount of Pt. A subsequent thermal dewetting step forms 3-6 nm-sized Pt nanoparticles along the nanofibrils. These structures, when compared to conventional Pt decoration techniques of TiO2 nanotubes, show strongly enhanced photocatalytic H2 evolution efficiency.

Nomasanguinicola canthoensis gen. et sp. n. infects the branchial vessels of bighead catfish, Clarias macrocephalus Gunther (Siluriformes: Clariidae), in the Mekong River near Can Tho, southern Vietnam. Nomasanguinicola differs from all other genera of fish blood flukes (Digenea: Aporocotylidae) by the combination of lacking body spines and by having an anterior sucker with two flanking columns of large denticles, an intestine comprising several short papilla-like caeca, an inverse U-shaped uterus, and an ootype located near the separate genital pores. The new species has an ootype that is posterior to the level of the female genital pore. That feature most easily differentiates it from the only other putative aporocotylid species having an anterior sucker with two flanking columns of large denticles, Plehniella dentata Paperna, 1964 and Sanguinicola clarias Imam, Marzouk, Hassan et Itman, 1984, which have an ootype that is lateral (P. dentata) or anterior (S. clarias) to the level of the female genital pore. These two species apparently lack extant type materials, infect North African catfish, Clarias gariepinus (Burchell), and herein are considered incertae sedis, but likely comprise species of Nomasanguinicola. An updated list of hosts, sites of infection and geographic localities for the six species and three genera of blood flukes that mature in catfishes is provided. The new species is the first fish blood fluke recorded from Vietnam and only the third reported from a walking catfish (Clariidae).

Ideally ordered TiO2 hole arrays with high aspect ratios were prepared by the anodization of pretextured Ti. The obtained TiO2 acted as two-dimensional photonic crystals in which a photonic band gap is formed in all directions of light propagation in the lattice. The process allows the easy and low-cost fabrication of TiO2 photonic crystals and can be used for the preparation of functional optical devices, which require the precise control of light propagation.

In 1995 Masuda et al. reported on a straightforward anodization approach that allowed for the growth of self-organized vertically-aligned alumina nanopores.1 Since then, electrochemical anodization has been widely investigated as a most suitable way to fabricate one dimensional (1D) functional oxide structures.2 Highly-ordered architectures of several metal oxides were successfully formed by anodizing in aqueous acidic solutions (e.g., Al2O3),1 fluoride containing aqueous or organic solvents (e.g., TiO2, Ta2O5, ZrO2, HfO2, etc.),3,4 and hot glycerol electrolytes (e.g., Al2O3, Ta2O5, TiO2).5-7 With this contribution we introduce a class of anodizing electrolytes, based on pure ortho-phosphoric acid (i.e., o-H3PO4), that provides high aspect-ratio highly-ordered oxide nanostructures on some of the most challenging elements such as W, as well as on more common elements such as Al, Ti, Nb.8 We describe how to tailor the structure of the formed anodic oxides by adjusting a set of key electrochemical parameters such as the electrolyte temperature, its water content, the applied voltage, and the anodization time. We show that under suitable conditions, an ideal equilibrium is established between field-assisted passivation of the metal and oxide dissolution, this leading to the growth of the anodic oxide layers in a highly ordered fashion. Not only pure molten ortho-phosphoric acid but also other phosphorus-containing acids, namely, hot pure pyro- and poly-phosphoric acids, are able to establish the required self-organizing electrochemical conditions for the growth of ordered oxide structures. We propose that the role of the molten phosphate electrolyte is two-fold: i) it provides an environment with controlled and limited water content (that is the key oxidant), and ii) it provides phosphate ions that protect the anodic oxide from rapid dissolution, this allowing for a controlled growth of the metal oxide nanostructures. (1) Masuda, H.; Fukuda, K. Science 1995, 268, 1466; (2) Roy, P.; Berger, S.; Schmuki, P. Angew. Chem. Int. Ed. 2011, 50, 2904; (3) Assefpour-Dezfuly, M. J. Mater. Sci. 1984, 19, 3626; (4) Kowalski, D.; Kim, D.; Schmuki, P. Nano Today 2013, 8, 235; (5) Melody, B.; Kinard, T.; Lessner, P. Electrochem. Solid-State Lett. 1999, 1, 126; (6) Lu, Q.; Alcalá, G.; Skeldon, P.; Thompson, G.; Graham, M. .; Masheder, D.; Shimizu, K.; Habazaki, H. Electrochim. Acta 2002, 48, 37; (7) Kim, D.; Lee, K.; Roy, P.; Birajdar, B.; Spiecker, E.; Schmuki, P. Angew. Chemie Int. Ed. 2009, 48, 9326; (8) Altomare, M.; Pfoch, O.; Tighineanu, A.; Kirchgeorg, R.; Lee, K.; Selli, E.; Schmuki, P. J. Am. Chem. Soc. 2015, 137, 5646. Figure 1

TiO2 nanostructures have recently attracted much attention due to their wide range of applications, such as photocatalysis, photovoltaics (dye-sensitized solar cell, photo-electrochemistry) and gas sensing. Particularly, electrochemically formed TiO2 nanotube arrays were shown to exhibit improved photocatalytic activity compared to other TiO2 nanostructures, this being ascribed to their directional electron transport and orthogonal charge carrier separation.1 The advantage of an electrochemical growth of the TiO2 nanotube layers is not only the simplicity of the process, but also the possibility of controlling the tube geometry (length, diameter, wall thickness) by selecting suitable anodization parameters (applied voltage, anodization time, temperature, fluoride concentration). Nevertheless, TiO2 alone is not effective in photocatalytic H2 generation: it requires the presence of noble metal co-catalysts (Pt, Au, Pd).2,3 Among the various noble metals, Pt is the most effective co-catalyst: it enables an efficient electron transfer at the semiconductor interface by providing a favorable solid state junction to TiO2 and it enhances the hydrogen recombination reaction. There are several well explored methods to decorate Pt onto TiO2 nanotubes, mostly leading to a decoration of the full tube length with nanoparticles (the most frequently used up to date is photodeposition). With our contribution we show a different approach: we decorate only the outermost surface of anodic TiO2 nanotubes with very thin Pt films (nominally few nm-thick) by using a simple plasma sputtering technique.4 Then, by a controlled thermal treatment, the Pt films are dewetted at the mouth of the tubes into arrays of Pt nanoparticles that are as small as of few nm. This site-selective deposition (only at the tubes top) allows for minimizing the amounts of costly noble metal co-catalyst, while at the same time leads to a significantly enhanced photocatalytic H2 generation compared to tubes that carry along their full length a classic Pt nanoparticle decoration. [1] K. Lee, A. Mazare, P. Schmuki, Chem. Rev. 2014, 114, 9385–9454. [2] N. T. Nguyen, J. Yoo, M. Altomare, P. Schmuki, Chem. Commun. 2014, 50, 9653–9656. [3] N. T. Nguyen, M. Altomare, J. Yoo, P. Schmuki, Adv. Mater. 2015, 27, 3208–3215. [4] N. T. Nguyen, M. Altomare, J. E. Yoo, N. Taccardi, P. Schmuki, Adv. Energy Mater. 2015, doi: 10.1002/aenm.201501926. Figure 1

In the last decades TiO2 has received large attention due to its ability to “photocatalytically” split H2O into H2 and O2. Under “open-circuit” conditions, noble metal-modified (mainly Pt, Au or Pd) TiO2 is needed for H2 photo-generation.1 Not only the presence but also the size, amount and distribution of the noble metal particles affect the photocatalytic efficiency of TiO2.2,3 In this contribution we show that a most effective way to control the size and distribution of co-catalytic nanoparticles deposited on ordered TiO2 nanotube arrays is a controlled sputter-dewetting process.4 For this, we first grow electrochemically highly-ordered arrays of short aspect-ratio TiO2 nanotube in a o-H3PO4/HF electrolyte.5 The tubes growth is based on a simple anodization of a Ti metal substrate in self-ordering electrochemical conditions, and the morphology of the formed tubular oxide structures can be simply adjusted by the experimental conditions. These arrays of TiO2 nanotubes are coated with sputtered Au and Ag films, and a following controlled thermal treatment is carried out that leads at the same time to Au-Ag alloying and thermal dewetting of the conformal metallic film, that is, the sputtered metals are converted into an array of orderly distributed alloyed Au-Ag nanoparticles. By adjusting the sputtering conditions, we are able to selectively deposit the Au-Ag nanoparticles at the rim and/or within the cavity of the TiO2 nanotubes. Subsequently, we perform a dealloying process, consisting in the selective chemical dissolution of Ag in a HNO3 solution, this leaving behind nanoporous Au particles on/into the tubes. Compared to tubes decorated by conventional approaches, remarkably enhanced photocatalytic H2 production is obtained upon porousification of the embedded Au nanoparticles. These porous Au/TiO2 nanotube structures show a remarkable photocatalytic enhancement particularly when the Au porous particles are selectively formed at the rims of the tubes (“crown” position). [1] K. Lee, A. Mazare, P. Schmuki, Chem. Rev. 2014, 114, 9385–9454. [2] N. T. Nguyen, J. Yoo, M. Altomare, P. Schmuki, Chem. Commun. 2014, 50, 9653–9656. [3] N. T. Nguyen, M. Altomare, J. E. Yoo, N. Taccardi, P. Schmuki, Adv. Energy Mater. 2015, doi: 10.1002/aenm.201501926. [4] N. T. Nguyen, M. Altomare, J. Yoo, P. Schmuki, Adv. Mater. 2015, 27, 3208–3215. [5] J. E. Yoo, K. Lee, M. Altomare, E. Selli, P. Schmuki, Angew. Chem. Int. Ed. 2013, 52, 7514–7517. Figure 1

In the last decades, one-dimensional (1D) nanostructured semiconductor have attracted large attention in the field of materials science owing to their enhanced physico-chemical properties such as large porosity and high specific surface area,1 orthogonal charge carrier separation and facilitated electron transport.2-5 With this contribution we focus particularly on WO3, as the synthesis of such defined architectures could not be achieved using common techniques, such as hydrothermal processes,6 spray pyrolysis,7 sputtering8 and thermal/e-beam evaporation.9,10 We introduce an anodization approach of W metal, based on the use of hot (nominally) pure ortho-phosphoric acid (i.e., o-H3PO4) as anodizing electrolytes, to form self-organized high aspect-ratio structures of WO3.11 Noteworthy, various other anodic growth pathways of porous WO3 are reported that however lead only to oxide architectures lacking of long range order,12-14 mainly because the anodization of W metal in common electrolytes produces highly soluble species (i.e., fast dissolution oxide rate) and this typically leads to a poor control over the anodic growth.15,16 The key of our approach is that the water content in the hot o-H3PO4 electrolyte (typically kept at ca. 100°C during anodization) is limited to traces, that is essential to reach a controlled growth of thick and ordered porous films.11,17 Under optimized electrochemical conditions, the formed anodic layers consist of highly-aligned WO3 nanopores with adjustable diameter (5-20 nm) and length (up to ~ 4 µm) that can reach an aspect-ratio of ~ 400. These 1D WO3 nanostructures, owing to their electronic and optical properties, advantageous directional charge transfer and enhanced gas diffusion and ion intercalation geometry (in comparison to devices fabricated from classical powder assemblies), can be suitably used in a large palette of applications as photocatalysts, electrodes for electrochromic devices and photo-electrochemical cells (i.e., H2 generation), and gas-sensors. (1) Roy, P.; Berger, S.; Schmuki, P. Angew. Chem. Int. Ed. 2011, 50, 2904; (2) Roy, P.; Kim, D.; Lee, K.; Spiecker, E.; Schmuki, P. Nanoscale 2010, 2, 45; (3) Crossland, E. J. W.; Noel, N.; Sivaram, V.; Leijtens, T.; Alexander-Webber, J. A.; Snaith, H. J. Nature 2013, 495, 215; (4) Altomare, M.; Lee, K.; Killian, M. S.; Selli, E.; Schmuki, P. Chem. Eur. J. 2013, 19, 5841; (5) So, S.; Schmuki, P. Angew. Chem. Int. Ed. 2013, 52, 7933; (6) Yang, P.; Zhao, D.; Margolese, D. Nature 1998, 396, 152; (7) Matei Ghimbeu, C.; van Landschoot, R. C.; Schoonman, J.; Lumbreras, M. Thin Solid Films 2007, 515, 5498; (8) Sberveglieri, G.; Depero, L.; Groppelli, S.; Nelli, P. Sensors Actuators B Chem. 1995, 26, 89; (9) Lee, S.; Cheong, H.; Tracy, C. E. Electrochim. Acta 1999, 44, 3111; (10) Antonaia, A.; Addonizio, M.; Minarini, C. Electrochim. Acta 2001, 46, 2221; (11) Altomare, M.; Pfoch, O.; Tighineanu, A.; Kirchgeorg, R.; Lee, K.; Selli, E.; Schmuki, P. J. Am. Chem. Soc. 2015, 137, 5646; (12) Mukherjee, N.; Paulose, M.; Varghese, O. K.; Mor, G. K.; Grimes, C. a. J. Mater. Res. 2011, 18, 2296; (13) Tsuchiya, H.; Macak, J. M.; Sieber, I.; Taveira, L.; Ghicov, A.; Sirotna, K.; Schmuki, P. Electrochem. commun. 2005, 7, 295; (14) Berger, S.; Tsuchiya, H.; Ghicov, A.; Schmuki, P. Appl. Phys. Lett. 2006, 88, 203119; (15) Di Paola, A.; Di Quarto, F.; Sunseri, C. Corros. Sci. 1980, 20, 1067; (16) Di Paola, A.; Di Quarto, F.; Sunseri, C. Corros. Sci. 1980, 20, 1079; (17) Wei, W.; Shaw, S.; Lee, K.; Schmuki, P. Chem. - A Eur. J. 2012, 18, 14622. Figure 1

Background Long-lasting insecticidal hammocks (LLIHs) are being evaluated as an additional malaria prevention tool in settings where standard control strategies have a limited impact. This is the case among the Ra-glai ethnic minority communities of Ninh Thuan, one of the forested and mountainous provinces of Central Vietnam where malaria morbidity persist due to the sylvatic nature of the main malaria vector An. dirus and the dependence of the population on the forest for subsistence - as is the case for many impoverished ethnic minorities in Southeast Asia. Methods A social science study was carried out ancillary to a community-based cluster randomized trial on the effectiveness of LLIHs to control forest malaria. The social science research strategy consisted of a mixed methods study triangulating qualitative data from focused ethnography and quantitative data collected during a malariometric cross-sectional survey on a random sample of 2,045 study participants. Results To meet work requirements during the labor intensive malaria transmission and rainy season, Ra-glai slash and burn farmers combine living in government supported villages along the road with a second home at their fields located in the forest. LLIH use was evaluated in both locations. During daytime, LLIH use at village level was reported by 69.3% of all respondents, and in forest fields this was 73.2%. In the evening, 54.1% used the LLIHs in the villages, while at the fields this was 20.7%. At night, LLIH use was minimal, regardless of the location (village 4.4%; forest 6.4%). Discussion Despite the free distribution of insecticide-treated nets (ITNs) and LLIHs, around half the local population remains largely unprotected when sleeping in their forest plot huts. In order to tackle forest malaria more effectively, control policies should explicitly target forest fields where ethnic minority farmers are more vulnerable to malaria.

Melanoma can adapt to several stress factors, such as TNF treatment, by changing its phenotype from a highly differentiated (MITF and MART-1 positive) to undifferentiated (neural crest markers) states. We studied this phenomenon as a mechanism of adaptive resistance to BRAF inhibition since melanomas with both MITF high and low have been reported to result in BRAF inhibitor resistance. We treated 17 BRAFV600E mutant melanoma cell lines with the BRAF inhibitor vemurafenib for short term (3 days) or long term (17 days), and compared them to no treatment or TNF treated conditions. We profiled them phenotypically for MART1 antigen (differentiated phenotype) and nerve growth factor receptor (NGFR, neural crest phenotype) expression by flow cytometry. Results comparing median fluorescence intensity (MFI) showed a wide spectrum of adaptive responses to short term BRAF inhibition, followed by solidification or further evolution of these changes upon long term exposure and development of drug tolerance. According to each cell line distribution, we calculated a (x,y) value that organized the cell lines and conditions in four quadrants according to MART1 (x axis) or NGFR (y axis) expression. Two double negative (MART1-/NGFR-) cell lines that were unaffected by treatment and stayed in the same quadrant. Seven MART1-/NGFR+ and four MART1+/NGFR- cell lines slightly changed phenotype with vemurafenib exposure but stayed in the same quadrant. Four cell lines with MART1+/NGFR+ phenotype were greatly influenced by treatment, showing wide plasticity with cells shifting towards NGFR+/MART1- and others towards NGFR-/MART1+. Changes in position between baseline and tolerance to vemurafenib after 17days treatment were numerically quantified as an inferred number from plasticity. Cell lines with double positive (MART1+/NGFR+) phenotype had a significant change in plasticity compared to the rest of cell lines in other quadrants (p = 0.0004). This arranges cells in a four-quadrant pattern that could be likened to a U-turn toward de-differentiation. Cells that de-differentiated with BRAF inhibition mimicked the effect induced by TNF. This effect was driven by a decrease in MITF activity confirmed with a tyrosinase promoter-luciferase assay. In conclusion, baseline melanoma differentiation phenotypes guide the phenotype switch response, with those double positive for differentiation and neural crest markers being at a semi-stable state that can be prone to different plastic changes upon BRAF inhibition. Citation Format: Lidia Robert, Jennifer Tsoi, Angel Garica Diaz, Blanca Homet Moreno, Nhat Truong, Thomas Graeber, Antoni Ribas. Melanoma phenotype switching to adapt to BRAF inhibition. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2682. doi:10.1158/1538-7445.AM2015-2682