SbCl3‐Al2O3–Catalyzed,Solvent‐Free,One‐Pot Synthesis of Benzo[b]1,4‐diazepines

This article explores the use of antimony(III) chloride adsorbed on neutral alumina as an efficient catalyst for the one‐pot synthesis of benzo[b]1,4‐diazepines (83–94%) under solvent‐free conditions. The process is easy, efficient, ecofriendly, and economical.     

Carbon black and propylene oxidation over Ru/CoxMgyAl2Oz catalysts

The effects of Co_xMg_yAl₂O_z mixed oxides composition and ruthenium addition on the oxidation of propylene and carbon black (CB) were investigated. Different reactive cobalt and ruthenium oxide species were formed following calcination at 600 °C. The addition of ruthenium was beneficial for the CB oxidation under “loose contact” conditions and for propylene oxidation when the cobalt content was intermediate to low. The calculated activation energy for CB oxidation was decreased from 151 kJ mol⁻¹ for the uncatalyzed reaction to 111 kJ mol⁻¹ over the best catalyst.     

A concise synthesis of Hagen’s gland lactones

A short synthesis of Hagen’s gland lactones 1 and 2 from commercially available pentanal and heptanal, respectively, is outlined. The approach relies on sequential ring closing metathesis and intramolecular oxy-Michael addition as the key transformations.     

A mini review on the generation of crimped ultrathin fibers via electrospinning: Materials,strategies, and applications

Structures modification of fibers has been attracting significant attention in various fields and applications. Among different techniques of fabricating ultrathin fibers, electrospinning is the most commonly adopted method because of the ease of forming fibers with a wide range of properties and its exceptional advantages, such as the ability to spin into different shapes and sizes, as well as the adaptable porosity of electrospun fiber webs. The crimped structure has been attracting the attention of scientific researchers owing to its unique properties (eg, spring‐like behavior, supreme strain, remarkable specific surface area, good piezoelectric properties, excellent biological properties, and so on). Therefore, this study summarizes a review of the strategies and methods, reported so far, of generating electrospun crimped ultrathin fibers of various polymers. The review focuses on the polymer types, formation methods, characterizations, and applications of the electrospun crimped ultrathin fibers. We believe this work can serve as an important reference for the materials, strategies, and applications of crimped fibers.     

Free‐Standing CoO‐POM Janus‐like Ultrathin Nanosheets

A single‐step solution‐based strategy is used to obtain 2D Janus‐like free‐standing ultrathin nanosheets build from two structurally unrelated species, that is, polyoxomolybdate (POM) and CoO. A controlled 2D‐to‐1D morphological transition was achieved by judiciously adjusting the solvent choice. These POM‐CoO heterostructures can behave as an ideal catalyst for the epoxidation of styrene. Benefiting from their amphiphilic nature, these 2D POM‐CoO nanosheets have also been used as surfactant to emulsify immiscible solvents. It is anticipated that structurally diverse polyoxometalates will offer promise as design elements for variety of structurally and compositionally tunable van der Waals integrated heteromaterials having a broad range applications.     

Characterization of a photonic active integrated antenna using a direct off-air transmission technique

This article presents a characterization study of a state-of-the-art 40 GHz mode-locked laser using a hybrid integrated microstrip patch antenna and bias-T circuit. A passive mode-locking range of 300 MHz is measured using this technique by tuning the gain and saturable absorber bias values for a maximum wireless distance of 15 cm. The passive mode-locking signal is detected by a direct off-air method from a photonic active integrated antenna. This signal can be used as a remote local oscillator to downconvert incoming signals as part of a bidirectional system for in-building/campus wide remote antenna units in next generation millimetre-wave radio-over-fibre systems.     

Support vector regression with digital band pass filtering for the quantitative analysis of near‐infrared spectra

This paper proposes a novel calibration technique based on combining support vector regression with a digital band pass (DBP) filter for the quantitative analysis of near‐infrared spectra. The efficacy of the proposed method is investigated and validated in the determination of glucose from near‐infrared spectra of a mixture composed of urea, triacetin and glucose. In this paper, the DBP filtering was implemented as a pre‐processing technique in the frequency domain as a Gaussian band pass filter and in the time domain as a Chebyshev filter. The grid‐search optimization method was used to optimize the filter parameters. The results demonstrate that utilization of the optimized DBP filters as a pre‐processing technique improved the performance of the predictive models. Copyright © 2013 John Wiley & Sons, Ltd.     

Ultraviolet Radiation Exposure and its Impacts on Cutaneous Phosphorylation Signaling in Carcinogenesis: Focusing on Protein Tyrosine Phosphatases†

Sunlight exposure is a significant risk factor for UV-induced deteriorating transformations of epidermal homeostasis leading to skin carcinogenesis. The ability of UVB radiation to cause melanoma, as well as basal and squamous cell carcinomas, makes UVB the most harmful among the three known UV ranges. UVB-induced DNA mutations and dysregulation of signaling pathways contribute to skin cancer formation. Among various signaling pathways modulated by UVB, tyrosine phosphorylation signaling which is mediated by the action of protein tyrosine kinases (PTKs) on specific tyrosine residues is highly implicated in photocarcinogenesis. Following UVB irradiation, PTKs get activated and their downstream signaling pathways contribute to photocarcinogenesis by promoting the survival of damaged keratinocytes and increasing cell proliferation. While UVB activates oncogenic signaling pathways, it can also activate tumor suppressive signaling pathways as initial protective mechanisms to maintain epidermal homeostasis. Tyrosine dephosphorylation is one of the protective mechanisms and is mediated by the action of protein tyrosine phosphatases (PTPs). PTP can counteract UVB-mediated PTK activation and downregulate oncogenic signaling pathways. However, PTPs have not been studied extensively in photocarcinogenesis with previous studies regarding their inactivation induced by UVB. This current review will summarize the recent progress in the protective function of PTPs in epidermal photocarcinogenesis.     

Simple high‐performance liquid chromatography method for formaldehyde determination in human tissue through derivatization with 2,4‐dinitrophenylhydrazine

A simple high‐performance liquid chromatography method has been developed for the determination of formaldehyde in human tissue. FA Formaldehyde was derivatized with 2,4‐dinitrophenylhydrazine. It was extracted from human tissue with ethyl acetate by liquid–liquid extraction and analyzed by high‐performance liquid chromatography. The calibration curve was linear in the concentration range of 5.0–200 μg/mL. Intra‐ and interday precision values for formaldehyde in tissue were <6.9%, and accuracy (relative error) was better than 6.5%. The extraction recoveries of formaldehyde from human tissue were between 88 and 98%. The limits of detection and quantification of formaldehyde were 1.5 and 5.0 μg/mL, respectively. Also, this assay was applied to liver samples taken from a biopsy material.     

Folic‐Acid‐Modified Conducting Polymer: Electrochemical Detection of the Cell Attachment

Here, postfunctionalization and bioapplication of a π‐conjugated polymer named 4‐[4H‐dithieno(3,2‐b:2′,3′‐d)pyrrol‐4‐yl]aniline (DTP‐aryl‐NH₂) are reported, which is successfully synthesized via electropolymerization onto the glassy carbon electrode. Folic acid (FA) is used to modify the amino functional polymer via N‐(3‐dimethylaminopropyl)‐N′‐ethylcarbodiimide hydrochloride/N‐hydroxysuccinimide chemistry for the further steps. The selective adhesion of folate receptor positive cells on the surface is followed by the electrochemical methods. Cyclic voltammetry and electrochemical impedance spectroscopy have been used to characterize stepwise modification of the electroactive surface. After optimization studies such as scan rate during the polymer deposition, FA amount for the efficient surface targeting, incubation time with the cells etc., analytical characterization is carried out. The surface morphologies at each step are imaged by using fluorescence microscopy.