An Orientation‐Independent Imaging Technique for the Classification of Blood Cells

This study presents an orientation independent imaging technique for the classification and recognition of blood cells with relevant applications to related problems in cytometry and medical diagnosis. The proposed method integrates three important aspects towards its practical implementation: 1. The use of the principal component (PC) transform to reorient in an optimal fashion the image data and to make of the feature matching an orientation independent process; 2. The establishment of similarity measures to quantify the matching process of the shape of the blood cell populations with any chosen degree of certainty; and 3. The application of the recognition and classification processes once all the similarity measurements are gathered. An extension of this two‐dimensional (2‐D) method to a three‐dimensional (3‐D) base is proposed. Results of this technique using real‐world image data of blood cell populations are given. It is appropriate to note that although the images used here are real‐world samples of blood cell populations, other samples containing different biological specimens could have been used just as well.     

Coordination Polymers of Polyphenyl-Substituted Potassium Cyclopentadienides

A series of potassium salts of di- and tri-arylsubstituted cyclopentadienes has been obtained by the metalation of the corresponding cyclopentadienes with benzylpotassium in THF media. Crystals of all compounds, afforded by recrystallization from THF/hexane, diglyme-THF/hexane and toluene/hexane mixtures, have been studied by X-ray diffraction. All studied potassium cyclopentadienides exhibit the luminescence at room temperature and overall quantum yield of photoluminescence for potassium salt of diarylsubstituted cyclopentadiene is 18%.     

Facile One‐pot Synthesis of Substituted Dihydropyrrol‐2‐ones via Four‐component Domino Reaction of Amines,Dialkyl Acetylenedicarboxylates and Formaldehyde

A mild and efficient method for the one‐pot synthesis of substituted dihydropyrrol‐2‐one derivatives is described via four‐component domino reaction of amines, dialkyl acetylenedicarboxyaltes and formaldehyde in the presence of 1‐methyl‐2‐oxopyrrolidinium hydrogen sulfate ([Hpyro][HSO₄]) as ionic liquid catalyst. This facile approach proceeded smoothly in good to high yields and pure products are separated from the reaction mixture by simple filtration.     

A low-cost environmentally friendly approach to isolate lignin containing micro and nanofibrillated cellulose from Eucalyptus globulus bark by steam explosion

Cellulose - Micro- and Nano-Fibrillated Cellulose (MNFC) have gained increasing attention due to their remarkable properties, but their production usually requires an intensive multi-step process....     

Cellular Uptake of the ATSM−Cu(II) Complex under Hypoxic Conditions

The Cu(II)-diacetyl-bis (N4-methylthiosemicarbazone) complex (ATSM−Cu(II)) has been suggested as a promising positron emission tomography (PET) agent for hypoxia imaging. Several in-vivo studies have shown its potential to detect hypoxic tumors. However, its uptake mechanism and its specificity to various cancer cell lines have been less studied. Herein, we tested ATSM−Cu(II) toxicity, uptake, and reduction, using four different cell types: (1) mouse breast cancer cells (DA-3), (2) human embryonic kidney cells (HEK-293), (3) breast cancer cells (MCF-7), and (4) cervical cancer cells (Hela) under normoxic and hypoxic conditions. We showed that ATSM−Cu(II) is toxic to breast cancer cells under normoxic and hypoxic conditions; however, it is not toxic to normal HEK-293 non-cancer cells. We showed that the Cu(I) content in breast cancer cell after treatment with ATSM−Cu(II) under hypoxic conditions is higher than in normal cells, despite that the uptake of ATSM−Cu(II) is a bit higher in normal cells than in breast cancer cells. This study suggests that the redox potential of ATSM−Cu(II) is higher in breast cancer cells than in normal cells; thus, its toxicity to cancer cells is increased.     

An efficient green synthesis of dispirohydroquinolines via a diastereoselective one-pot eight-component reaction

The one-pot eight-component reaction between Meldrum's acid, an aromatic aldehyde, and an aryl amine was achieved in the presence of citric acid catalyst. The corresponding dispirohydroquino-lines were obtained in good yields with excellent diastereoselectivity. This method is a combination of the Knoevenagel and Michael reactions.     

A Mild and Environmentally Benign Synthesis of Tetrahydrobenzo[b]pyrans and Pyrano[c]chromenes Using Pectin as a Green and Biodegradable Catalyst

Pectin was applied as a green and biodegradable catalyst for the one‐pot three‐component synthesis of tetrahydrobenzo[b]pyrans and pyrano[c]chromenes, from the condensation between aromatic aldehydes, malononitrile, and dimedone or 4‐hydroxycumarine at ambient temperature. This protocol has many advantages such as mild conditions, high yields, environmental benignity, simple work‐up procedures, short reaction time, as well as the use of a natural, easily accessible, convenient handling, and inexpensive catalyst. Another advantage of this method is that the products do not require further purification such as column chromatography.     

Introduction of antimony triiodide (SbI3) as a new and efficient catalyst for synthesis of polyfunctionalized piperidines

Research on Chemical Intermediates - In the present work, an efficient and convenient one-pot multi-component reaction is reported for the synthesis of highly diversified piperidines by tandem...