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We present the synthesis, through a simple, microwave-assisted method, of lanthanoid-based 2D metal–organic frameworks (MOFs) of general formula [LnxLn′1−x(MeCOO)(PhCOO)2], including homonuclear compounds (x = 1), Ln＝Eu, Tb, and heterometallic compounds, [TbEu]. The crystalline material is formed by neutral nanosheets held together by van der Waals interactions, which can be easily exfoliated by sonication. Photoluminescent emission in the visible range was observed for all of the synthesized 2D MOF compounds via excitation of the ligand, showing benzoates are efficient antenna ligands. Efficient energy transfer from Tb → Eu was observed in the heterometallic [TbEu] compounds, which could potentially perform as luminescent thermometers. Inks containing nanosheets of 2D MOFs exfoliated in solution were prepared, and luminescent prints of Tb and Eu 2D MOFs on paper were made to show the possible application for anticounterfeiting. Frequency-dependent ac susceptibility results show the occurrence of slow magnetic relaxation in [TbEu] compounds through direct relaxation mechanisms, affected by bottleneck effect. A slowing down of the relaxation time is observed as the Eu/Tb ratio increases. [ABSTRACT FROM AUTHOR]

Describir las técnicas «radioguided occult lesion localization» (ROLL) y «sentinel node occult lesion localization» (SNOLL) guiadas por resonancia magnética (RM) para el marcaje de restos tumorales en pacientes con cáncer infiltrante de mama que han recibido quimioterapia neoadyuvante y presentar los resultados quirúrgicos y la supervivencia libre de enfermedad. Estudio observacional prospectivo de 132 pacientes correspondientes a 136 tumores, tratadas con quimioterapia neoadyuvante en nuestro hospital entre los años 2011 a 2017 y marcadas preoperatoriamente con ROLL/SNOLL guiado con RM. Se describieron los aspectos técnicos de localización del lecho tumoral residual y se registraron variables correspondientes a los procedimientos quirúrgicos y eventos ocurridos durante el seguimiento. La mediana de tamaño tumoral fue 20,5 mm (rango intercuartílico [RIC]:14 a 28). El 96,3% eran carcinomas ductales infiltrantes. La tasa de detección del ganglio centinela fue 98,9% y se obtuvo respuesta completa patológica (RCP) en el 58,1%. La tasa de bordes afectos en los 89 casos operados mediante cirugía conservadora fue del 2,2%. Con una mediana de seguimiento de 50 meses (RIC: 37 a 61) se observó un 7,4% de recaídas, siete locorregionales y tres a distancia. La media estimada de supervivencia libre de enfermedad fue de 83,2 meses (Intervalo de Confianza [IC] 95%: 79,6 a 86,6). La técnica ROLL/SNOLL guiada con RM es útil en el marcaje de los restos tumorales tras neoadyuvancia, proporcionando unos resultados quirúrgicos adecuados y un buen control locorregional. To describe the results of MRI (magnetic resonance image) guided ROLL (radioguided occult lesion localization) and SNOLL (sentinel node occult lesion localization) in the localization of residual disease after neoadjuvant chemotherapy for breast cancer, as well as assessing the surgical results obtained and disease free survival. Prospective observational analysis of 132 patients with 136 tumors, treated with neoadjuvant chemotherapy at our hospital between 2011-2017. Residual disease was located presurgically with MRI guided ROLL/SNOLL technique. We analyzed technical aspects of localization, and variables corresponding to surgical procedures and events occurred during follow-up. The median tumor size was of 20.5mm (interquartilic range [IQR]: 14-28). The majority (96.3%) were invasive ductal carcinomas. Sentinel lymph node detection rate was 98.9%. Complete pathological response (CPR) in the breast was achieved in 58.1% of cases. The rate of affected margins in 89 cases operated by conservative surgery was 2.2%. With a median follow-up of 50 months (IQR: 37-61) we found a 7.4% rate of relapses. Of these, seven were loco-regional and three at distant sites. The estimated mean of disease-free survival time was 83.2 months (Confidence Interval [CI] 95%: 79.6-86.6). MRI guided ROLL/SNOLL is a great tool for breast cancer residual disease localization following neoadjuvant chemotherapy. In addition, this technique attains good loco-regional control of the diseases and has excellent surgical results. [ABSTRACT FROM AUTHOR]

Coumarin-based lanthanide complexes of general formula [Ln(coum)3(phen)(H2O)x]·yH2O (Ln-phen, x = 0,1, 0 ≤ y ≤ 1.5; phen = 1,10-phenanthroline; coum = 3-acetyl-4-hydroxylato-coumarin; Ln = Eu, Tb, Dy, Tm) and [Ln(coum)3(batho)]·0.7EtOH (Ln-batho, batho = 4,7-diphenyl-1,10-phenanthroline; Ln = Eu, Tb, Dy, Tm) were synthesized. The magnetic relaxation and photoluminescence behavior of these complexes was compared with that of the related compounds [Ln(coum)3(EtOH)(H2O)]·EtOH (Ln-coum), so as to investigate the effects of incorporating a second chromophore, either the phen or batho ligand, to the original coordination scaffold, provided with three coumarin (coum) ligands. Slow relaxation of the magnetization under H = 0 with moderate activation energies was observed for the Dy-phen (U/kB = 99.1 K) and Dy-batho (U/kB = 67.1 K) compounds, whereas Tb analogues presented field-induced single molecule magnet (SMM) behavior, with U/kB = 11.7 K (16.6 K@3 kOe) for Tb-phen (Tb-batho), respectively. Luminescent emission in the visible range was observed for all the Ln-coumarin based compounds upon ligand sensitization, with high quantum yields of 45 (40%) for Eu-phen (Eu-batho) compounds and 65–76–58% for Tb-coum, phen, batho analogues. Sensitization is mainly provided by the coumarin ligand having the energy difference ΔE between its triplet state T1 and the lanthanide emitting level closest to the optimum, while the second ligand can play either a synergistic or competing sensitizing role. The Tb-phen/batho compounds presented simultaneously SMM and luminescent behavior, with excellent values of the bifunctional figure of merit (ηSMM–QY ∼ 1000% K). The reported compounds represent a new class of bifunctional materials with potential interesting application in various fields. [ABSTRACT FROM AUTHOR]

We report the synthesis, crystal structure and photo-magnetic properties of novel Tb/Eu polymeric complexes of general formula {TbxEu1−x(α-fur)3(H2O)3}n, supported by 2-furancarboxilic acid: the homonuclear Tb(iii) complex {Tb} (1), four heterodinuclear complexes, {Tb0.8Eu0.2} (2), {Tb0.7Eu0.3} (3), {Tb0.3Eu0.7} (4), and {Tb0.1Eu0.9} (5), and the homonuclear Eu(iii)-only complex {Eu} (6). X-ray diffraction experiments show that the α-furoate ligands, acting in bridging mode, consolidate the 1D polymeric chains along the c-axis. Luminescence studies show the sensitization capability of the furoic acid ligand. Color tuning from green to red can be successfully achieved through the heterodinuclear strategy. We have measured Eu emission by direct excitation at the resonant 7F0→5L6 (395 nm), and indirectly, by excitation of the non-resonant wavelength (280 nm) which provokes ligand → Tb → Eu energy transfer. Besides, ac susceptibility measurements under varying frequencies and temperatures reveal that mixed {TbxEu1−x} complexes exhibit field-induced slow relaxation dynamics, with extremely slow relaxation times, owing to direct processes affected by the bottleneck effect. Thus, the {TbxEu1−x} complexes represent interesting low-dimensional multifunctional materials combining both luminescent and SMM magnetic properties. [ABSTRACT FROM AUTHOR]

Selective, robust and cost-effective chemical sensors for detecting small volatile-organic compounds (VOCs) have widespread applications in industry, healthcare and environmental monitoring. Here we design a Pt(II) pincer-type material with selective absorptive and emissive responses to methanol and water. The yellow anhydrous form converts reversibly on a subsecond timescale to a red hydrate in the presence of parts-per-thousand levels of atmospheric water vapour. Exposure to methanol induces a similarly-rapid and reversible colour change to a blue methanol solvate. Stable smart coatings on glass demonstrate robust switching over 104 cycles, and flexible microporous polymer membranes incorporating microcrystals of the complex show identical vapochromic behaviour. The rapid vapochromic response can be rationalised from the crystal structure, and in combination with quantumchemical modelling, we provide a complete microscopic picture of the switching mechanism. We discuss how this multiscale design approach can be used to obtain new compounds with tailored VOC selectivity and spectral responses. [ABSTRACT FROM AUTHOR]

Two examples of anionic complexes having vapochromic behavior are investigated: [K(H2O)][Pt(ppy)(CN)2] “Pt(ppy)” and [K(H2O)][Pt(bzq)(CN)2] “Pt(bzq)”, where ppy = 2-phenylpyridinate and bzq = 7,8-benzoquinolate. These monohydrate-potassium salts exhibit a change in color from purple to yellow [Pt(ppy)] and from red to yellow [Pt(bzq)] upon heating to 110 °C, and they transform back into the original color upon absorption of water molecules from the environment. Available only in the form of polycrystalline samples, no structural information on such compounds is accessible, due to highly overlapping peaks in powder diffraction profiles. We use in situ Pair Distribution Function measurements on powder samples to investigate the dynamics of the structural changes induced by temperature variations. By means of a multivariate approach, we were able to extract dynamic structural information from collected profiles without using prior knowledge on the static crystal structure of the compounds. The critical temperature and the characteristics of the vapochromic transition have been identified, as well as the main structural changes causing it. [ABSTRACT FROM AUTHOR]

• Both implicit and explicit measures were needed to understand consumers' response. • The extrinsic properties were the drivers of the consumers' response. • PDO logo familiarity was related with a low emotional activation. The aim of the present study was to determine the implicit and explicit responses of consumers when evaluating two apple ciders of the same brand, being one of the samples a protected designation of origin (PDO) product. Samples were tested in blind conditions to determine if liking was different and was driven by the sensory properties. Then, brand images were also evaluated by consumers. Finally, the products were tested providing consumers with information about the specific cider that they were testing: showing the brand images during the test. The first phase of the study was designed to determine the implicit reaction of 52 consumers, recorded using biosensors capable of measuring skin conductance variations. For this phase, approximately 50% of consumers were familiar with the PDO logo, while the other 50% was not aware of the logo significance, and was clarified before the test. During the second phase of the study, the response of the consumers who were related with the logo significance was further investigated. A total of 65 consumers who were familiar with the PDO significance were recruited, and the same samples than in phase I were assessed. Liking, as well as emotions, using the EsSense25 lexicon, were documented. Significant differences were detected in arousal, and also in impact, between consumers groups. On the contrary, when studying the explicit response, liking and emotions were not significantly different for both cider samples. Implicit reaction might have indicated additional information which was lost when a rationalized response was provided. [ABSTRACT FROM AUTHOR]