RESUMO
SrMn2P2 and CaMn2P2 are insulators that adopt the trigonal CaAl2Si2-type structure containing corrugated Mn honeycomb layers. Magnetic susceptibility χ and heat capacity versus temperature T data reveal a weak first-order antiferromagnetic (AFM) transition at the Néel temperature [Formula: see text] K for SrMn2P2 and a strong first-order AFM transition at [Formula: see text] K for CaMn2P2 Both compounds exhibit isotropic and nearly T-independent [Formula: see text], suggesting magnetic structures in which nearest-neighbor moments are aligned at [Formula: see text] to each other. The 31P NMR measurements confirm the strong first-order transition in CaMn2P2 but show critical slowing down above [Formula: see text] for SrMn2P2, thus also evidencing second-order character. The 31P NMR measurements indicate that the AFM structure of CaMn2P2 is commensurate with the lattice whereas that of SrMn2P2 is incommensurate. These first-order AFM transitions are unique among the class of (Ca, Sr, Ba)Mn2 (P, As, Sb, Bi)2 compounds that otherwise exhibit second-order AFM transitions. This result challenges our understanding of the circumstances under which first-order AFM transitions occur.
RESUMO
This study was conducted to analyze a comprehensive panel of single nucleotide polymorphisms (SNP) in DNA repair genes to determine the relationship between polymorphisms and the survival outcome of patients with early stage non-small-cell lung cancer (NSCLC). Three hundred and ten consecutive patients with surgically resected NSCLC were enrolled. Forty-eight SNP in 27 DNA repair genes were genotyped and their associations with overall survival (OS) and disease-free survival (DFS) were analyzed. Individually, six SNP exhibited significant associations with survival outcome. When the six SNP were combined, OS and DFS decreased as the number of bad genotypes increased (P(trend) <0.0001 for both). Patients with three, and four or five bad genotypes had a significantly worse OS and DFS compared with those carrying zero or one bad genotypes (adjusted hazard ratio [aHR] for OS=3.53, 95% confidence interval [CI]=1.25-9.97, P=0.02, and aHR for DFS=3.31, 95% CI=1.41-7.76, P=0.006; and aHR for OS=5.47, 95% CI=1.87-16.00, P=0.002, and aHR for DFS=4.42, 95% CI=1.82-10.74, P=0.001, respectively). These findings suggest that the six SNP identified can be used as prognostic markers for patients with surgically resected early stage NSCLC.