Selective growth of ag nanowires on Si(111) surfaces by electroless deposition

Electroless deposition of Ag on atomically flat H-terminated Si(111) surfaces in aqueous alkaline solutions containing Ag ions produced two different sizes of Ag nanowires along atomic step edges: (1) a narrow nanowire of 10 nm in width and 0.5 nm in height and (2) a wide nanowire of 35 nm in width and 11 nm in height. The narrow and wide nanowires were formed by immersion in the solutions containing less than 1 ppb and 8 ppm dissolved-oxygen concentrations, respectively. This result indicates that the dissolved oxygen initiates the formation of Ag nucleation sites and that the fabrication method has a possibility of controlling the size of Ag nanowires.     

The number of labeled graphs placeable by a given permutation

Let S be a finite set and σ a permutation on S. The permutation σ* on the set of 2-subsets of S is naturally induced by σ. Suppose G is a graph and V(G), E(G) are the vertex set, the edge set, respectively. Let V(G) = S. If E(G) and σ*(E(G)), the image of E(G) by σ*, have no common element, then G is said to be placeable by σ. This notion is generalized as follows. If any two sets of {E(G), (σ¹)*(E(G)),…,(σ^l−1)* (E(G))} have no common element, then G is said to be I-placeable by σ. In this paper, we count the number of labeled graphs which are I-placeable by a given permutation. At first, we introduce the interspaced Ith Fibonacci and Lucas numbers. When I = 2 these numbers are the ordinary Fibonacci and Lucas numbers. It is known that the Fibonacci and Lucas numbers are rounded powers. We show that the interspaced Ith Fibonacci and Lucas numbers are also rounded powers when I = 3. Next, we show the number of labeled graphs which are I-placeable by a given permutation is a product of the interspaced Ith Lucas numbers. Finally, using a property of the generalized binomial series, we count the number of labeled graphs of size k which are I-placeable by σ. © 1996 John Wiley & Sons, Inc.     

Improved book-embeddings of incomplete hypercubes

In this paper, we show that any incomplete hypercube with, at most, 2ⁿ+2ⁿ⁻¹+2ⁿ⁻² vertices can be embedded in n−1 pages for all n≥4. For the case n≥4, this result improves Fang and Lai’s result that any incomplete hypercube with, at most, 2ⁿ+2ⁿ⁻¹ vertices can be embedded in n−1 pages for all n≥2.Besides this, we show that the result can be further improved when n is large — e.g., any incomplete hypercube with at most 2ⁿ+2ⁿ⁻¹+2ⁿ⁻²+2ⁿ⁻⁷ (respectively, 2ⁿ+2ⁿ⁻¹+2ⁿ⁻²+2ⁿ⁻⁷+2ⁿ⁻²³⁰) vertices can be embedded in n−1 pages for all n≥9 (respectively, n≥232).     

Conducting-AFM spectroscopy on ultrathin SiO2 films

We study the dielectric degradation phenomena of ultrathin SiO₂ films using conducting-AFM spectroscopy in a vacuum (1᎒^-5 Pa). In successive current-voltage characteristics, a change of the carrier transport (from Fowler-Nordheim tunneling to direct tunneling) and current instability (which is due to a change in conductance of leakage path by isolated traps) are observed before 'breakdown'. As an example of a possible application of conducting-AFM spectroscopy, we investigate a change in conductivity at a 'breakdown' area.     

Reduced stress‐optical coefficient of polycarbonate by antiplasticization

We have investigated the effect of antiplasticization on the stress‐optical behavior of polycarbonate (PC) containing terphenyls (tPh) and di(2‐ethylhexyl)adipate (DEHA). Addition of the three tPhs (p‐, o‐, and m‐tPh) and DEHA at contents of 5–10 wt % increases the tensile storage modulus (E' ) of PC owing to the antiplasticization effect. In particular, p‐tPh increases E' more than the other additives, suggesting that the rod‐like shape matches the free volume of PC in the glassy state. The three tPh isomers improve the glassy birefringence of PC while DEHA does not change the glassy birefringence, which corresponds to the polarizability anisotropy. The stress‐optical coefficient, a ratio of stress and birefringence, of PC decreases with increasing additive content in order of p‐tPh ? o‐tPh > m‐tPh = DEHA. This result is agreement with a restricted rotational motion of additive molecule in PC, which is observed in dynamic mechanical and birefringence data. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55 , 1837–1842     

Enzyme display technology for lignocellulosic biomass valorization by yeast cell factories

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ATP-GTP-BINDING PROTEINS AND ENDOGENOUS ADP-RIBOSYL TRANSFERASE IN Lemna paucicostata 441

Abstract— A crude extract containing membrane components of Lemna paucicostata was treated with 1% Lubrol PX and fractionated by gel nitration. Binding activities to non-hydrolyzable analogues of ATP, [³⁵S]ATPγS (adenosine 5'[;γ-thio]triphosphate) and that of GTP, [³⁵S]GTPγS (guanosine 5'[γ-thiojtriphosphate) were detected in some fractions, and these activities were prevented in the presence of 0.1 mM ATP or GTP. ATP and GTP were 2 to 3 orders of magnitude more effective than CTP or UTP in preventing this binding activity. These fractions showed ATPase and GTPase activities with 1 nM [γ-³²P]ATP or [γ–³²P]GTP substrate. Analyses by sodium dodecyl sulfate polyacrylamide gel electrophoresis of these fractions after binding with [³⁵S]ATPγS or [³⁵S]GTP-γ S revealed that these fractions contained [³⁵S]ATPγS and [³⁵S]GTPγS binding proteins with molecular weights of 53 000 and 60 000, respectively. Both of these proteins were [³²P]ADP-ribosylated by endogenous ADP-ribosyl transferase. Three proteins with molecular weights of 11 000, 12 000 and 13 000 which could bind [³⁵S]ATP7S or [-³⁵S]GTP-γ S were ADP-ribosylated by endogenous ADP-ribosyl transferase. Pertussis toxin stimulated ADP-ribosylation of these proteins. Four proteins with molecular weight of 37 000, 50 000, 80 000 and 115 000 with P^SS]ATP7S and [^,3S]GTP7S binding activities were also detected. The signal transduction of light to underlying clock mechanism in Lemna may be controlled by ATP-GTP-binding proteins and by the ADP-ribosylation of these proteins.     

4-Ketoantheraxanthin, a novel carotenoid produced by the combination of the bacterial enzyme β-carotene ketolase CrtW and endogenous carotenoid biosynthetic enzymes in higher plants

Higher plants do not ordinarily possess ketocarotenoids due to the absence of a carotenoid ketolase enzyme. We expressed genes coding for marine-bacterial enzymes β-carotene ketolase (CrtW) and β-carotene hydroxylase (CrtZ) in tobacco plants (Nicotiana tabacum) by transplastomic engineering. A novel carotenoid, 4-ketoantheraxanthin, was isolated from the leaves of the tobacco transformants. The structure of 4-ketoantheraxanthin was determined to be (3S,3′S,5′R,6′S)-5′,6′-epoxy-3,3′-dihydroxy-β,β-caroten-4-one by analysis of the MS, NMR, and CD data. This carotenoid was considered to be synthesized by a 4-ketolation reaction by CrtW of antheraxanthin that had been synthesized by the endogenous carotenoid biosynthetic enzymes present in higher plants and CrtZ. 4-Ketoantheraxanthin was also shown to have potent antioxidative activity against a ¹O₂ suppression model.     

Queue layouts of iterated line directed graphs

In this paper, we study queue layouts of iterated line directed graphs. A k-queue layout of a directed graph consists of a linear ordering of the vertices and an assignment of each arc to exactly one of the k queues so that any two arcs assigned to the same queue do not nest. The queuenumber of a directed graph is the minimum number of queues required for a queue layout of the directed graph.We present upper and lower bounds on the queuenumber of an iterated line directed graph L^k(G) of a directed graph G. Our upper bound depends only on G and is independent of the number of iterations k. Queue layouts can be applied to three-dimensional drawings. From the results on the queuenumber of L^k(G), it is shown that for any fixed directed graph G, L^k(G) has a three-dimensional drawing with O(n) volume, where n is the number of vertices in L^k(G). These results are also applied to specific families of iterated line directed graphs such as de Bruijn, Kautz, butterfly, and wrapped butterfly directed graphs. In particular, the queuenumber of k-ary butterfly directed graphs is determined if k is odd.     

Independent spanning trees with small depths in iterated line digraphs

We show that the independent spanning tree conjecture on digraphs is true if we restrict ourselves to line digraphs. Also, we construct independent spanning trees with small depths in iterated line digraphs. From the results, we can obtain independent spanning trees with small depths in de Bruijn and Kautz digraphs that improve the previously known upper bounds on the depths.