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Flexible smart sensing skin is a key enabling technology for the future “Fly-by-Feel” control of morphing aircraft. It represents the next-generation skin of aircraft that can exhibit a more powerful sensing function than a conventional one and could be mounted on arbitrary curvilinear surfaces, especially for advanced autonomic, morphing aircraft. Recent significant technical advances in flexible electronics have overcome many historic drawbacks of conventional smart skin, e.g., only a limited number of discrete block sensors can be integrated due to the inevitable structural damage and heavy guidelines. Herein, we review the key developments in flexible sensors technology and highlight both the state-of-the-art devices and the potential applications for the measurement of aircraft. We begin with the importance of flexible smart skin for morphing aircraft and then expand to the latest progress in various types of flexible sensors. Then we highlight flexible sensors as smart skin to measure aerodynamic parameters and monitor the structural health, and further to achieve the Fly-by-Feel control. Finally, the challenges and opportunities on flexible smart sensing skin are discussed, from the functional design to practical applications.

Ion-pair reversed-phase nano liquid chromatography coupled with nanospray ion trap mass spectrometry was used to investigate site selectivity of the known carcinogens N-acetoxy-2-acetylaminofluorene, N-hydroxy-4-aminobiphenyl and (±)-anti-benzo[a]pyrene diol epoxide with the synthetic double-strand 14-mer long oligonucleotide fragment of the p53gene containing two mutational hot-spot codons (5'- P- ACC155CGC156GTC157CGC158GC/5'- GCG CGG ACG CGG GT). The investigation was performed using a monolithic polystyrene divinylbenzene capillary column and triethylammonium bicarbonate as an ion-pair reagent. The exact location of the carcinogen on the modified oligonucleotide backbone was determined using characteristic collision-induced dissociation fragmentation patterns obtained under negative-ion mode ionization. In all these cases, the adducted, isomeric oligonucleotides formed were chromatographically resolved and structural identification was performed without any prior deoxyribonucleic acid cleavage or hydrolysis. The knowledge of the site specificity of a carcinogen, especially at purported mutational hot spots, is of paramount importance (1) in establishing the identity of biomarkers for an early risk assessment of the formed DNA adducts, (2) developing repair mechanisms for the formed carcinogen adducted DNA, and (3) understanding the nature of the covalent bond formed and mapping the frequency of the adduction process.

Benzo[a]pyrene is a major carcinogen implicated in human lung cancer. Almost 60% of human lung cancers have a mutation in the p53tumor suppressor gene at several specific codons. An on‐line nanoLC/MS/MS method using a monolithic nanocolumn was applied to investigate the chemoselectivity of the carcinogenic diol epoxide metabolite, ( ± )‐(7R,8S,9S,10R)‐benzo[a]pyrene 7,8‐diol 9,10‐epoxide [( ± )‐anti‐benzo[a]pyrene diol epoxide (BPDE)], which was reacted in vitrowith a synthesized 14‐mer double stranded oligonucleotide (5′‐ACCCG5CG7TCCG11CG13C‐3′/5′‐GCGCGGGCGCGGGT‐3′) derived from the p53gene. This sequence contained codons 157 and 158, which are considered mutational ‘hot spots’ and have also been reported as chemical ‘hot spots’ for the formation of BPDE‐DNA adducts. In evaluating the effect of cytosine methylation on BPDE‐DNA adduct binding, it was found that codon 156, containing the nucleobase G5instead of the mutational hot spot codons 157 (G7) and 158 (G11), was the preferential chemoselective binding site for BPDE. In all permethylated cases studied, the relative ratio for adduction was found to be G5≫ G11> G13> G7. Permethylation of CpG dinucleotide sites on either the nontranscribed or complementary strand did not change the order of sequence preference but did enhance the relative adduction level of the G11CpG site (codon 158) approximately two‐fold versus the unmethylated oligomer. Permethylation of all CpG dinucleotide sites on the duplex changed the order of relative adduction to G5≫ G7> G11> G13. The three‐ to four‐fold increase in adduction at the mutational hot spot codon 157 (G7) relative to the unmethylated or single‐stranded permethylated cases suggests a possible relationship between the state of methylation and adduct formation for a particular mutation site in the p53gene. Using this method, only 125 ng (30 pmol) of adducted oligonucleotide was analyzed with minimal sample cleanup and high chromatographic resolution of positional isomers in a single chromatographic run. Copyright © 2009 John Wiley & Sons, Ltd.

Developing multifunctional flying perceptibility, by mimicking the biological system, is meaningful for aircrafts to adapt to the complicated and ambiguous flow environment. In this work, we show that the comprehensive capabilities (skin, synapse, immune system, and brain) of flying creatures can serve as bio-inspirations to develop an intelligent flexible sensing (iFlexSense) skin with similar components, i.e., skin-like mechanosensing, neuron-like data transmission, immune system-like impact monitoring and brain-like artificial intelligence. The iFlexSence skin brings substantial improvements to the aircrafts by the multifunctionalities including airflow perception, state awareness and self-diagnosis of complex surfaces, validated by the wind tunnel tests mounted on a NACA 0012 airfoil, in which it accurately measures the surface pressure, temperature, wall shear stress and flutter, locates the sudden impacts and correctly predicts the occurrence of separation and stall. It shows great potential for future wind tunnel tests and to extend the capabilities of unmanned air vehicles and underwater vehicles.

Large, 3D curved electronics are a trend of the microelectronic industry due to their unique ability to conformally coexist with complex surfaces while retaining the electronic functions of 2D planar integrated circuit technologies. However, these curved electronics present great challenges to the fabrication processes. Here, we propose a reconfigurable, mask-free, conformal fabrication strategy with a robot-like system, called robotized 'transfer-and-jet' printing, to assemble diverse electronic devices on complex surfaces. This novel method is a ground-breaking advance with the unique capability to integrate rigid chips, flexible electronics, and conformal circuits on complex surfaces. Critically, each process, including transfer printing, inkjet printing, and plasma treating, are mask-free, digitalized, and programmable. The robotization techniques, including measurement, surface reconstruction and localization, and path programming, break through the fundamental constraints of 2D planar microfabrication in the context of geometric shape and size. The transfer printing begins with the laser lift-off of rigid chips or flexible electronics from donor substrates, which are then transferred onto a curved surface via a dexterous robotic palm. Then the robotic electrohydrodynamic printing directly writes submicrometer structures on the curved surface. Their permutation and combination allow versatile conformal microfabrication. Finally, robotized hybrid printing is utilized to successfully fabricate a conformal heater and antenna on a spherical surface and a flexible smart sensing skin on a winged model, where the curved circuit, flexible capacitive and piezoelectric sensor arrays, and rigid digital-analog conversion chips are assembled. Robotized hybrid printing is an innovative printing technology, enabling additive, noncontact and digital microfabrication for 3D curved electronics.

Previous research has shown that compounds with mixed kappa and mu activity may have utility for the treatment of cocaine abuse and dependence. The present study characterizes the pharmacological profile of a bivalent morphinan that was shown to be a kappa opioid receptor agonist and a mu opioid receptor agonist/antagonist. MCL-145 [bis(N-cyclobutylmethylmorphinan) fumarate] is related to the morphinan cyclorphan and its N-cyclobutylmethyl derivative MCL-101 [3-hydroxy-N-cyclobutylmethyl morphinan S-(+)-mandelate]. MCL-145 consists of two morphinans connected by a spacer at the 3-hydroxy position. This compound had K(i) values of 0.078 and 0.20 nM for the kappa and mu opioid receptors, respectively, using radioligand binding assays as shown by Neumeyer et al. in 2003. In the guanosine 5'-O -(3-[(35) S]thiotriphosphate) binding assay, MCL-145 produced an E(max) value of 80% for the kappa opioid receptor and 42% for the mu opioid receptor. The EC(50) values obtained for this compound were 4.3 and 3.1 nM for the kappa and mu opioid receptors, respectively. In vivo MCL-145 produced a full dose-response curve in the 55 degrees C warm water tail-flick test and was equipotent to morphine. The agonist properties of MCL-145 were antagonized by the mu-selective antagonist beta-funaltrexamine and the kappa-selective antagonist nor-binaltorphimine. MCL-145 also acted as a mu antagonist, as measured by the inhibition of morphine-induced antinociception.

Trifluoromethylated polyfunctionalized cyclopropanes were obtained in high stereoselectivity by reacting 2-bromo-3,3,3-trifluoropropene (BrTFP) with active methylenes. This novel method was further applied to the synthesis of (±)-trans-trifluoronorcoronamic acid.

A new Lewis acid, Zn(ODf)₂, was first prepared from commercially available 3,3,4,4-tetrafluoro[1,2]oxathietane 2,2-dioxide in four steps with 56% yields and also was applied to catalyze highly enantioselective alkynylation of aldehydes in the presence of ligand (1S,2S)-3-(tert-butyldimethylsilyloxyl)-2-N,N-dimethylamino-1-(p-nitrophenyl)propane-1-ol or ligand (−)-N-methylephedrine to afford the corresponding propargylic alcohols in high yields with up to 99% ee.

A new inexpensive chiral amino alcohol-based ligand, (1S,2S)-2-N,N-dimethylamino-1-(p-nitrophenyl)-3-(t-butyldimethylsilyloxy)propane-1-ol, was developed for the asymmetric alkynylation of aliphatic and aromatic aldehydes, to prepare the corresponding propargylic alcohols in high yields with up to 99% ee.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.