Single crystalline orthorhombic phase tungsten trioxide monohydrate (O-WO 3 •H 2 O, space group: Pmnb) nanoplates with a clear morphology and uniform size distribution have been synthesized by the hydrothermal method and fabricated on the surface of fluorine doped tin oxide (FTO) coated glass substrates with selective exposure of the crystal facet by the finger rubbing method. The rubbing method can easily arrange the O-WO 3 •H 2 O nanoplates along the (020) facet on the FTO substrate. The O-WO 3 •H 2 O nanoplate can be converted to monoclinic phase WO 3 (γ-WO 3 , space group: P21/n) with dominant crystal facet of (002) without destroying the plate structure. Crystal morphologies, structures, and components of the powders and films have been determined by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman, X-ray photoelectron spectroscopy, etc. The band gap energies of the O-WO 3 •H 2 O and γ-WO 3 nanoplates were determined as ca. 2.26 and 2.49 eV, respectively. Photoelectrochemical properties of the films with (002) dominant crystal facet have also been checked for discussion of further application in water oxidation. The advantage of (002) facet dominant film was investigated by comparing to one spin-coated γ-WO 3 thin film with the same thickness via photoelectrochemical characterizations such as photocurrent, incident photon to current efficiency, and electrochemical impedance spectroscopy.

mobility and fast charge recombination, which result in limitations during practical application. Because the solar light conversion effi ciency ( η ) [ 15 ] is directly proportional to the product of the solar light absorption effi ciency ( η abs ), charge separation effi ciency ( η sep ), and surface charge transfer effi ciency ( η trans ). The decoration of the cocatalyst [ 16 ] and the introduction of porosity to increase surface area [ 17 ] have been studied for practical usage of PEC with increased η abs , η sep , and η trans . Specifically, recent developments in the fully integrated nanowire-based heterostructure [ 18,19 ] and the introduction of a dual-layer oxidation cocatalyst [ 20 ] into porous BiVO 4 have been reported for practical solar fuel production with good η abs , η sep , and η tran .However, the typical PEC performance of a pristine BiVO 4 photoanode to produce solar fuel products is not impressive because it suffers from inherent drawbacks. The development and design of BiVO 4 microcrystals have been highlighted to produce solar fuel products by introducing photocatalytic crystal facet engineering and cocatalyst, [20][21][22] and the breakthrough for enhancing solar light conversion effi ciency has not been suggested previously for a pristine BiVO 4 photoanode.Here, a (040)-crystal facet engineered BiVO 4 ((040)-BVO) plate photoanode has been investigated to produce solar fuel products as an artifi cial photosynthesis with highly enhanced PEC performance via a crystal facet engineering approach that is based on reports by Cheng and co-workers [ 23,24 ] and Li and co-workers. [ 11,21,22 ] We demonstrate the higher PEC performance caused by higher effi cient η sep and η tran of the BVO thin fi lm with selectively exposed (040) crystal facet. Because the (040) facet-manipulated BiVO 4 plate photoanode has not been previously studied, our designed model demonstrates the signifi cance of the interfacial electron transport reaction between the {010} plane and the electrolyte with η sep and η tran , resulting in the highest PEC performance. The results of this study may provide the most viable strategy for designing an effi cient BiVO 4 photoanode for enhanced solar fuel production. Results and DiscussionA (040)-crystal facet engineered BiVO 4 plate photoanode ((040)-BVO) was hydrothermally synthesized via a seed layer approach A (040)-crystal facet engineered BiVO 4 ((040)-BVO) photoanode is investigated for solar fuel production. The (040)-BVO photoanode is favorable for improved charge carrier mobility and high photocatalytic active sites for solar light energy conversion. This crystal facet design of the (040)-BVO photoanode leads to an increase in the energy conversion effi ciency for solar fuel production and an enhancement of the oxygen evolution rate. The photocurrent density of the (040)-BVO photoanode is determined to be 0.94 mA cm −2 under AM 1.5 G illumination and produces 42.1% of the absorbed photon-to-current conversion effi ciency at 1.23 V (vs RHE, reversible hydrogen electrode). ...

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Development of biomaterial-based bioinks is critical for replacement and/or regeneration of tissues and organs by three-dimensional (3D) printing techniques. However, the number of 3D-printable biomaterials in practical use remains limited despite the rapid development of 3D printing techniques. Controlling the flow properties of bioinks and mechanical properties of the resultant printed objects is key considerations in the design of biomaterial-based bioinks for practical applications. In this study, a printable hydrogel comprising biocompatible polysaccharides that has potential for cartilage regeneration via tissue engineering approaches was designed. Self-healing hydrogels were prepared from partially oxidized hyaluronate (OHA) and glycol chitosan (GC) in the presence of adipic acid dihydrazide (ADH). The self-healing ability of OHA/GC/ADH hydrogels was attributed to the combination of two dynamic bonds in the gels, including imine bonds obtained via a Schiff base reaction between OHA and GC, as well as acylhydrazone bonds formed by the reaction between OHA and ADH. The OHA/GC/ADH hydrogels did not require any postgelation or additional cross-linking processes for use in the fabrication of 3D constructs using an extrusion-based 3D printer. The concentrations and molecular weights of the constituent polymers were found to be critical parameters affecting the flow and mechanical properties of the self-healing hydrogels, which showed great potential as bioinks for fabricating cell-laden structures using a 3D printer. The expression of chondrogenic marker genes such as SOX-9 and collagen type II of ATDC5 cells encapsulated in the OHA/GC/ADH hydrogel was not significantly affected by the printing process. This self-healing hydrogel system may have the potential in tissue engineering applications, including cartilage regeneration.

sensors, [8][9][10] and structural camouflage. [1,2] When paired with auditory counterpart, i.e., sound, the color facilitates the effective transfer of information from devices to humans, therein rationalizing the stereotypical designs of contemporary devices, which contain both sound and color modules. With regard to color, nature has, via evolution, mastered the art of emitting and reflecting light, as evidenced by bioluminescence, [11] and structural color, [12] which in turn, can be juxtaposed with man-made emissive displays [13] and structural materials with photonic band gaps, [14] respectively. Indeed, while most artificial photonic devices intrinsically lack the ability to modulate their output color once their periodicity is fixed, [15] some creatures, such as cephalopods [4] and chameleons, [3] have overcome this constraint in an extrinsic manner by stretching their skin. Inspired by these naturally evolved systems, there has been an explosion of research [16] into deformable skins capable of color tunability to produce mechanochromic systems, [17][18][19] though these systems have their own inherent disadvantages, [8,16,20,21] including slow response rates, limited ranges of tunability, and high propensity for electrical and mechanical failure.Transducing electrical energy in the form of excitation voltages in a dielectric elastomer actuator (DEA) [22][23][24][25] grants us access to large areal strains with high response rates by way of induced Maxwell stress across a dielectric medium. The introduction of a photonic layer between the two electrodes of the DEA, however, increases the requisite working threshold voltage to effect the required transduction and thereby the likelihood of dielectric breakdown. [26] This complication can be resolved by attaching the photonic layer to the exterior of the DEA. [27] In this regard, using hydrogels that are intrinsically soft, comparable to biological tissue (Young's modulus, E < 1 MPa), stretchable and able to withstand significant physical deformation in their swollen state [17,28,29] would appear to be an obvious choice. However, as their superior properties are so heavily reliant on their water contents, the ease of evaporation and high vapor pressure of their solvent (for water, ≈2.3 kPa) compared to other organic solvents (e.g., ethylene glycol, EG, ≈0.5 kPa) render them ill-suited for this particular application, which necessitates long-lasting softness. Here we demonstrate a photonic organogel [poly(2-hydroxyethyl methacrylate-co-acrylamide) (pHEMA-co-AAm)] with EG as the solvent to sustain the Color, as perceived through the eye, transcends mere information in the visible range of electromagnetism and serves as an agent for communication and entertainment. Mechanochromic systems have thus far only aimed at satisfying the sense of vision and have overlooked the possibility of generating acoustic vibrations in concert with their visual color responses that would enable the simultaneous satisfaction of the auditory system. Transcending the boundaries of ...

Background: Combination chemotherapy using oxaliplatin, 5-fluorouracil and folinic acid (FOLFOX) is known to be effective in the treatment of metastatic colon cancer. Genes regulating the actions of 5-fluorouracil and oxaliplatin have been identified, but precisely which gene is dominant has not yet been determined. The aim of the investigation reported here was to identify which gene polymorphism is a dominant factor in FOLFOX chemotherapy-the methylenetetrahydrofolate reductase (MTHFR) gene for 5-fluorouracil or the X-ray crosscomplementing1 (XRCC1) gene for oxaliplatin.Methods: Paraffin-embedded tissues from 54 patients with unresectable metastases from colorectal cancer who had undergone chemotherapy with the FOLFOX regimen were analyzed for MTHFR polymorphisms in the MTHFR gene (677C!T, Ala!Val mutation) and XRCC1 gene (Arg!Gln substitution in exon 10). Response rates and survivals were compared by types of polymorphism.Results: Analyses of the patterns of MTHFR polymorphism revealed that 29.6% of the patients showed no mutation, 51.6% showed heterozygous mutations, and 11.8% showed homozygous mutations. Analyses of the XRCC1 polymorphism revealed that 60.8% of the patients showed no mutation, 31.4% showed heterozygous mutations, and 7.8% showed homozygous mutations. After four cycles of chemotherapy, 3.7% showed a complete response, 57.4% showed a partial response (PD) or stable disease, and 38.9% showed PD. The MTHFR polymorphism was not significant in predicting response and 30-month-survival (P > 0.1), whereas the XRCC1 polymorphism was a significant prognostic factor for both response (P = 0.038) and survival (P = 0.011).Conclusions: We found a higher rate of mutations in the MTHFR gene than in the XRCC1 gene in Korean colorectal cancer patients. Response to FOLFOX was better in the patient group with mutations for MTHFR and worse in the patient group with mutations for XRCC1. However, only the XRCC1 polymorphism was a significant prognostic factor for the response to FOLFOX chemotherapy and short-term survival.

Research Summary: Ethnic migrant inventors may differ from locals in terms of the knowledge they bring to host firms. Using a unique dataset of Chinese and Indian herbal patents filed in the United States, we find that an increase in the supply of first-generation ethnic migrant inventors increases the rate of codification of herbal knowledge at U.S. assignees by 4.5%. Our identification comes from an exogenous shock to the quota of H1B visas and from a list of entities exempted from the shock. We also find that ethnic migrant inventors are more likely to engage in reuse of knowledge previously locked within the cultural context of their home regions, whereas knowledge recombination is more likely to be pursued by teams comprising inventors from other ethnic backgrounds. Managerial Summary: Managers and policy makers around the world face a vigorous debate on whether to hire skilled migrants or hire locals. We argue that if western firms stop hiring ethnic migrants, innovation at these firms would suffer in two ways: knowledge transfer and knowledge recombination would both be impeded. We argue and show that skilled ethnic migrants bring to their employers, unique knowledge from the cultural context of their host country. Also, local inventors engage in "knowledge recombination" by combining their existing knowledge to knowledge transferred by migrants. Our empirical results relate to the patenting of Chinese and Indian herbal formulations at western pharmaceutical firms before and after an immigration shock related to the admittance of skilled migrants from these two countries.

Membranes with nano-apertures are versatile templates that possess a wide range of electronic, optical and biomedical applications. However, such membranes have been limited to silicon-based inorganic materials to utilize standard semiconductor processes. Here we report a new type of flexible and free-standing polymeric membrane with nano-apertures by exploiting high-wettability difference and geometrical reinforcement via multiscale, multilevel architecture. In the method, polymeric membranes with various pore sizes (50-800 nm) and shapes (dots, lines) are fabricated by a hierarchical mould-based dewetting of ultravioletcurable resins. In particular, the nano-pores are monolithically integrated on a two-level hierarchical supporting layer, allowing for the rapid (o5 min) and robust formation of multiscale and multilevel nano-apertures over large areas (2 Â 2 cm 2 ).