Nanoimprint Lithography (NIL) has been an interesting and growing field in recent years since its beginnings in the mid-1990s. During that time, nanoimprinting has undergone significant changes and ...developments and nowadays is a technology used in R&D labs and industrial production processes around the world. One of the exciting things about nanoimprinting process is its remarkable versatility and the broad range of applications. This reprint includes ten articles, which represent a small glimpse of the challenges and possibilities of this technology. Six contributions deal with nanoimprint processes aiming at specific applications, while the other four papers focus on more general aspects of nanoimprint processes or present novel materials. Several different types of nanoimprint processes are used: plate-to-plate, roll-to-plate, and roll-to-roll. Plate-to-plate NIL here also includes the use of soft and flexible stamps. The application fields in this reprint are broad and can be identified as plasmonics, superhydrophibicity, biomimetics, optics/datacom, and life sciences, showing the broad applicability of nanoimprinting. The sections on the nanoimprint process discuss filling and wetting aspects during nanoimprinting as well as materials for stamps and imprinting.
The involvement of salicylic acid (SA) in the regulation of stress-induced flowering in the short-day plant pharbitis (also called Japanese morning glory) Ipomoea nil (formerly Pharbitis nil) was ...studied. Pharbitis cv. Violet was induced to flower when grown in 1/100-strength mineral nutrient solution under non-inductive long-day conditions. All fully expanded true leaves were removed from seedlings, leaving only the cotyledons, and flowering was induced under poor-nutrition stress conditions. This indicates that cotyledons can play a role in the regulation of poor-nutrition stress-induced flowering. The expression of the pharbitis homolog of PHENYLALANINE AMMONIA-LYASE, the enzyme activity of phenylalanine ammonia-lyase (PAL; E.C. 4.3.1.5) and the content of SA in the cotyledons were all up-regulated by the stress treatment. The Violet was also induced to flower by low-temperature stress, DNA demethylation and short-day treatment. Low-temperature stress enhanced PAL activity, whereas non-stress factors such as DNA demethylation and short-day treatment decreased the activity. The PAL enzyme activity was also examined in another cultivar, Tendan, obtaining similar results to Violet. The exogenously applied SA did not induce flowering under non-stress conditions but did promote flowering under weak stress conditions in both cultivars. These results suggest that stress-induced flowering in pharbitis is induced, at least partly, by SA, and the synthesis of SA is promoted by PAL.
It is shown that over an arbitrary field there exists a nil algebra R whose adjoint group R^{o} is not an Engel group. This answers a question by Amberg and Sysak from 1997. The case of an ...uncountable field also answers a recent question by Zelmanov. In 2007, Rump introduced braces and radical chains A^{n+1}=A\cdot A^{n} and A^{(n+1)}=A^{(n)}\cdot A of a brace A. We show that the adjoint group A^{o} of a finite right brace is a nilpotent group if and only if A^{(n)}=0 for some n. We also show that the adjoint group A^{o} of a finite left brace A is a nilpotent group if and only if A^{n}=0 for some n. Moreover, if A is a finite brace whose adjoint group A^{o} is nilpotent, then A is the direct sum of braces whose cardinalities are powers of prime numbers. Notice that A^{o} is sometimes called the multiplicative group of a brace A. We also introduce a chain of ideals A^{n} of a left brace A and then use it to investigate braces which satisfy A^{n}=0 and A^{(m)}=0 for some m, n. We also describe connections between our results and braided groups and the non-degenerate involutive set-theoretic solutions of the Yang-Baxter equation. It is worth noticing that by a result of Gateva-Ivanova braces are in one-to-one correspondence with braided groups with involutive braiding operators.
The light- and indole-3-acetic acid (IAA)-regulated 1-aminocyclopropane-1-carboxylic acid (ACC) synthase gene (
PnACS) from
Pharbitis nil was isolated. Here, it was shown that the gene was expressed ...in cotyledons, petioles, hypocotyls, root and shoot apexes both in light- and dark-grown seedlings. The highest expression level of
PnACS was found in the roots. IAA applied to the cotyledons of
P. nil seedlings caused a clear increase of
PnACS messenger accumulation in all the organs examined. In this case, the most IAA-responsive were the hypocotyls. Our studies revealed that the
PnACS transcript level in the cotyledons exhibited diurnal oscillations under both long-day (LD) and short-day (SD) conditions. IAA applied at the beginning of inductive darkness caused a dramatic increase in the expression of
PnACS, suggesting that the inhibitory effect of IAA on
P. nil flowering may result from its stimulatory effect on ethylene production.
In flowering plants, floral longevity is species‐specific and is closely linked to reproductive strategy; petal senescence, a type of programmed cell death (PCD), is a highly regulated developmental ...process. However, little is known about regulatory pathways for cell death in petal senescence, which is developmentally controlled in an age‐dependent manner. Here, we show that a NAC transcription factor, designated EPHEMERAL1 (EPH1), positively regulates PCD during petal senescence in the ephemeral flowers of Japanese morning glory (Ipomoea nil). EPH1 expression is induced independently of ethylene signaling, and suppression of EPH1 resulted in Japanese morning glory flowers that are in bloom until the second day. The suppressed expression of EPH1 delays progression of PCD, possibly through suppression of the expression of PCD‐related genes, including genes for plant caspase and autophagy in the petals. Our data further suggest that EPH1 is involved in the regulation of ethylene‐accelerated petal senescence. In this study, we identified a key regulator of PCD in petal senescence, which will facilitate further elucidation of the regulatory network of petal senescence.
For a fixed natural number
an element a of a ring R is m-nil clean if
where
and b is nilpotent; if further eb = be, a is called strongly m-nil clean. The ring R is called m-nil clean (resp., strongly ...m-nil clean) if each of its elements is m-nil clean (resp., strongly m-nil clean). For a fixed natural number
the strongly m-nil clean rings are a big subclass of the periodic rings which contains the class of strongly nil clean rings. The strongly m-nil cleanness of the tensor product of algebras, matrix rings, Morita contexts, and group rings is discussed in detail. Our results extend several existing results. Examples are provided to illustrate our results.
The plot-culture experiments were conducted for examining the feasibility of
Pharbitis nil L. and its microbial community to remedy petroleum contaminated soils. The petroleum contaminated soil, ...containing 10% (w/w) of the total petroleum hydrocarbons (TPHs), was collected from the Shengli Oil Field, Dongying City, Shandong Province, China. The collected soil was applied and diluted to a series of petroleum contaminated soils (0.5%, 1.0%, 2.0% and 4.0%). Root length, microbial populations and numbers in the rhizosphere were also measured in this work. The results showed that there was significantly (
p
<
0.05) greater degradation rate of TPHs in vegetated treatments, up to 27.63–67.42%, compared with the unvegetated controls (only 10.20–35.61%), after a 127-day incubation. Although various fractions of TPHs had an insignificant concentration difference due to the presence of the remediation plants, there was a much higher removal of saturated hydrocarbon compared with other components. The biomass of
P. nil L. did not decrease significantly when the concentration of petroleum hydrocarbons in soil was ≤
2.0%. The trends of microbial populations and numbers in the rhizosphere were similar to the biomass changes, with the exception that fungi at 0.5% petroleum contaminated soil had the largest microbial populations and numbers.
The short-day plants
Pharbitis nil (synonym
Ipomoea nil), var. Violet and Tendan were grown in a diluted nutrient solution or tap water for 20 days under long-day conditions. Violet plants were ...induced to flower and vegetative growth was inhibited, whereas Tendan plants were not induced to flower, although vegetative growth was inhibited under these conditions. The Violet plants induced to flower by poor-nutrition stress produced fertile seeds and their progeny developed normally. Defoliated Violet scions grafted onto the rootstocks of Violet or Tendan were induced to flower under poor-nutrition stress conditions, but Tendan scions grafted onto the Violet rootstocks were not induced to flower. These results indicate that a transmissible flowering stimulus is involved in the induction of flowering by poor-nutrition stress. The poor-nutrition stress-induced flowering was inhibited by aminooxyacetic acid, a phenylalanine ammonia-lyase inhibitor, and this inhibition was almost completely reversed by salicylic acid (SA). However, exogenously applied SA did not induce flowering under non-stress conditions, suggesting that SA may be necessary but not sufficient to induce flowering.
PnFT2, a
P. nil ortholog of the flowering gene
FLOWERING LOCUS T (
FT) of
Arabidopsis thaliana, was expressed when the Violet plants were induced to flower by growing in tap water, but expression of
PnFT1, another ortholog of
FT, was not induced, suggesting the specific involvement of
PnFT2 in stress-induced flowering.
The plant hormone auxin plays a critical role in regulating plant growth and development. Recent advances have been made that having improved our understanding of auxin response pathways, primarily ...by characterizing the genes encoding auxin response factors (ARFs) in Arabidopsis. In addition, the expression of some ARFs is regulated by microRNAs (miRNAs). In Arabidopsis thaliana, ARF6 and ARF8 are targeted by miR167, whereas ARF10, ARF16 and ARF17 are targeted by miR160. Nevertheless, little is known about any possible interactions between miRNAs and the auxin signaling pathway during plant development. In this study, we isolated the miR167 target gene InARF8 cDNA from the cotyledons of the short day plant (SDP) Ipomoea nil (named also Pharbitis nil). Additionally, the In-miR167 precursor was identified from the I. nil EST database and analyses of InARF8 mRNA, In-pre-miR167 and mature miR167 accumulation in the plant's vegetative and generative organs were performed. The identified cDNA of InARF8 contains a miR167 complementary sequence and shows significant similarity to ARF8 cDNAs of other plant species. The predicted amino acid sequence of InARF8 includes all of the characteristic domains for ARF family transcription factors (B3 DNA-binding domain, AUX/IAA-CTD and a glutamine-rich region). Quantitative RT-PCR reactions and in situ hybridization indicated that InARF8 was expressed primarily in the shoot apices, leaf primordia and hypocotyls of I. nil seedlings, as well as in flower pistils and petals. The InARF8 transcript level increased consistently during the entire period of pistil development, whereas in the stamens, the greatest transcriptional activity occurred only during the intensive elongation phase. Additionally, an expression analysis of both the precursor In-pre-miR167 molecules identified and mature miRNA was performed. We observed that, in most of the organs examined, the InARF8 expression pattern was opposite to that of MIR167, indicating that the gene's activity was regulated by mRNA cleavage. Our findings suggested that InARF8 and InMIR167 participated in the development of young tissues, especially the shoot apices and flower elements. The main function of MIR167 appears to be to regulate InARF8 organ localization.
Japanese morning glory,
Ipomoea nil
, exhibits a variety of flower colours, except yellow, reflecting the accumulation of only trace amounts of carotenoids in the petals. In a previous study, we ...attributed this effect to the low expression levels of carotenogenic genes in the petals, but there may be other contributing factors. In the present study, we investigated the possible involvement of carotenoid cleavage dioxygenase (CCD), which cleaves specific double bonds of the polyene chains of carotenoids, in the regulation of carotenoid accumulation in the petals of
I. nil
. Using bioinformatics analysis, seven
InCCD
genes were identified in the
I. nil
genome. Sequencing and expression analyses indicated potential involvement of
InCCD4
in carotenoid degradation in the petals. Successful knockout of
InCCD4
using the CRISPR/Cas9 system in the white-flowered cultivar
I. nil
cv. AK77 caused the white petals to turn pale yellow. The total amount of carotenoids in the petals of
ccd4
plants was increased 20-fold relative to non-transgenic plants. This result indicates that in the petals of
I. nil
, not only low carotenogenic gene expression but also carotenoid degradation leads to extremely low levels of carotenoids.