Identification of the phosphorus-doping defect in MgS as a potential qubit

The P_(S) defect is obtained by replacing one S atom with one P atom in the wide-bandgap semiconductor Mg S.Based on first-principles calculations,the formation energy,defect levels,and electronic structure of the PSdefect in different charge states are evaluated.We predict that the neutral P^(0)_(S)and positively charged P^(+1)_(S)are the plausible qubit candidates for the construction of quantum systems,since they maintain the spin conservation during optical excited transition.The zero-phonon lines at the P^(0)_(S)and P^(+1)_(S)defects are 0.43 e V and 0.21 e V,respectively,which fall in the infrared band.In addition,the zero-field splitting parameter D of the P^(+1)_(S)with spin-triplet is 2920 MHz,which is in the range of microwave,showing that the P^(+1)_(S)defect can be manipulated by microwave.Finally,the principal values of the hyperfine tensor are examined,it is found that they decay exponentially with the distance from the defect site.

Cardiac Na^(+)-Ca^(2+) exchanger 1(ncx1h)is critical for the ventricular cardiomyocyte formation via regulating the expression levels of gata4 and hand2 in zebrafish

Ca^(2+) signaling is critical for heart development;however,the precise roles and regulatory pathways of Ca^(2+) transport proteins in cardiogenesis remain largely unknown.Sodium-calcium exchanger 1(Ncx1)is responsible for Ca^(2+) efflux in cardiomyocytes.It is involved in cardiogenesis,while the mechanism is unclear.Here,using the forward genetic screening in zebrafish,we identified a novel mutation at a highly-conserved leucine residue in ncx1 gene(mutant^(LDD353)/ncx1h^(L154P))that led to smaller hearts with reduced heart rate and weak contraction.Mechanistically,the number of ventricular but not atrial cardiomyocytes was reduced in ncx1h^(L154P) zebrafish.These defects were mimicked by knockdown or knockout of ncx1h.Moreover,ncx1h^(L154P) had cytosolic and mitochondrial Ca^(2+) overloading and Ca^(2+) transient suppression in cardiomyocytes.Furthermore,ncx1h^(L154P) and ncx1h morphants downregulated cardiac transcription factors hand2 and gata4 in the cardiac regions,while overexpression of hand2 and gata4 partially rescued cardiac defects including the number of ventricular myocytes.These findings demonstrate an essential role of the novel 154th leucine residue in the maintenance of Ncx1 function in zebrafish,and reveal previous unrecognized critical roles of the 154th leucine residue and Ncx1 in the formation of ventricular cardiomyocytes by at least partially regulating the expression levels of gata4 and hand2.