Reliable and precise methods capable of unambiguously identifying target analytes in real-world samples are indispensable in various fields, ranging from biological studies and diagnosis to quality control. Among various analytic techniques, nuclear magnetic resonance (NMR) is uniquely powerful as it provides multidimensional data useful for structural analysis at the atomic level. The rich information obtained from various NMR experiments allows one to access not only molecular structures and interactions but also the dynamics and diffusional properties. However, the interpretation of NMR data in the analysis of real-world mixtures can be challenging and is often complicated by the overlap of the NMR resonances of each component. Moreover, the inherently low sensitivity of the NMR technique hampers its implementation in many detections, where the analytes of interest are present at low concentrations. By a combination of heteronuclear NMR, dedicatedly designed sensors, ingenious transduction mechanisms, and powerful NMR pulse sequences, significant advancements were made to conquer these limitations. The present review summarizes the sensing systems that effectively facilitate NMR-based detection with an emphasis on the chemical perspective of sensor design and transduction mechanism. Advances in hyperpolarized sensors to boost the sensitivity of detection will also be included where appropriate.

The discovery of uncommon DNA structures and speculation about their potential functions in genes has brought attention to specific DNA structure recognition. G-quadruplexes are four-stranded nucleic acid structures formed by G-rich DNA (or RNA) sequences. G-rich sequences with a high potential to form G-quadruplexes have been found in many important genomic regions. Porphyrin derivatives with cationic side arm substituents are important G-quadruplex-binding ligands. For example, 5,10,15,20-Tetrakis(N-methylpyridinium-4-yl)-21H,23H-porphyrin (TMPyP4), interacts strongly with G-quadruplexes, but has poor selectivity for G-quadruplex versus duplex DNA. To increase the G-quadruplex recognition specificity, a new cationic porphyrin derivative, 5,10,15,20-tetra-{4-[2-(1-methyl-1- piperidinyl)ethoxy]phenyl} porphyrin (TMPipEOPP), with large side arm substituents was synthesized, and the interactions between TMPipEOPP and different DNA structures were compared. The results show that G-quadruplexes cause large changes in the UV-Vis absorption and fluorescence spectra of TMPipEOPP, but duplex and single-stranded DNAs do not, indicating that TMPipEOPP can be developed as a highly specific optical probe for discriminating G-quadruplex from duplex and single-stranded DNA. Visual discrimination is also possible. Job plot and Scatchard analysis suggest that a complicated binding interaction occurs between TMPipEOPP and G-quadruplexes. At a low [G-quadruplex]/[TMPipEOPP] ratio, one G-quadruplex binds two TMPipEOPP molecules by end-stacking and outside binding modes. At a high [G-quadruplex]/[TMPipEOPP] ratio, two G-quadruplexes bind to one TMPipEOPP molecule in a sandwich-like end-stacking mode.

ObjectivesWarfarin is often used for ischemic stroke prevention in patients with atrial fibrillation (AF), but the factors affecting patient adherence to warfarin therapy have not been fully understood.MethodsA cross-sectional survey was conducted in AF patients undergoing warfarin therapy at least 6 months prior to the study. The clinical data collected using questionnaires by phone interviews included the following: 1) self-reported adherence measured by the Morisky Medication Adherence Scale-8©; 2) beliefs about medicines surveyed by Beliefs about Medicines Questionnaire (BMQ); and 3) drug knowledge as measured by the Warfarin Related Knowledge Test (WRKT). Demographic and clinical factors associated with warfarin adherence were identified using a logistic regression model.ResultsTwo hundred eighty-eight patients completed the survey and 93 (32.3%) of them were classified as nonadherent (Morisky Medication Adherence Scale-8 score <6). Major factors predicting warfarin adherence included age, cardiovascular disorders, WRKT, and BMQ; WRKT and BMQ were independently correlated with adherence to warfarin therapy by multivariate logistic regression analysis. Adherents were more likely to have greater knowledge scores and stronger beliefs in the necessity of their specific medications ([odds ratio {OR} =1.81, 95% confidence interval {CI} =1.51–2.15] and [OR =1.17, 95% CI =1.06–1.29], respectively). Patients with greater concerns about adverse reactions and more negative views of general harm were more likely to be nonadherent ([OR =0.76, 95% CI =0.69–0.84] and [OR =0.82, 95% CI =0.73–0.92], respectively).ConclusionBMK and WRKT are related with patient behavior toward warfarin adherence. BMQ can be applied to identify patients at increased risk of nonadherence.

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The ocean–continent transition/conjunction zone is a mysterious and significant region in global tectonics and geodynamic evolution. The South China Sea (SCS) is one of the largest marginal basins in the Western Pacific with significant Cenozoic magmatic activities. The relationship between the tectono‐magmatic evolution and the tectonic setting of these Cenozoic igneous rocks is still controversial. In this study, the interpretation of gravity data, magnetic observation and seismic profiles is combined to identify the Cenozoic igneous rocks in the SCS and adjacent regions, and more than 70 magmatic activities have been discerned. We also show how the tectonic movements control the lithology and distribution of these magmatic activities. These Cenozoic magmatic rocks are related to the pre‐spreading, syn‐spreading and post‐spreading of the SCS. We suggest a geodynamic evolution of the SCS according to the temporal and spatial distribution of the igneous rocks. (1) An early period of bimodal volcanism (>32 Ma ago) mainly happened in the Paleogene basins at the northern margin of the SCS. This earlier volcanism happened under a trans‐extensional regime, which resulted from the collision between the Indian and the Eurasian plates since the early Cenozoic. The magmatic rocks may be related to the NNE‐trending right‐stepping dextral strike‐slip faults and the syn‐kinematic pull‐apart basins. These igneous rocks are mostly NNE trending. It is consistent with the Cenozoic dextral trans‐extensional tectonic setting in the East Asian Continental Margin. (2) Syn‐spreading igneous rocks first formed in the Northwest Sub‐basin of the SCS, and then later in the Central and Southwest sub‐basins. The mechanism of the magmatic emplacement results from the NNE‐trending right‐stepping dextral strike‐slip pull‐apart tectonic activity. (3) The spatial alignment of the Quaternary post‐spreading basalts is nearly E–W‐trending, and the different magmatic zones are segmented by NNE‐trending strike‐slip faulting. These volcanics are under an extrusion regime, which resulted from the arc–continent collision between the Luzon–Taiwan Arc and the Eurasian Plate due to the continuously WNW‐directed indentation of the Philippine Sea Plate during the period 9–6 Ma ago. In addition, the nascent NNE trending and dextral Changle–Nanao Fault may have played a significant role in the southward extrusion of the Taiwan Island Arc and the southeast SCS, resulting in an E–W‐trending distribution or strike of the volcanics and normal faults. In Indochina and the Malay Peninsula, widespread Cenozoic extensional post‐spreading granitic plutons are possibly derived from the mantle plume. Magnetic anomaly interpretation and tectonic analysis on these mafic rocks suggest that they were controlled by the Ailaoshan Red River left‐lateral ductile strike‐slip fault zone. Copyright © 2016 John Wiley & Sons, Ltd.

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