A quantum gate: A system of two coupled electron spins that is useful for simple quantum computing operations has been prepared by synthesis of a biradical 1 and co-crystallization with an isomorphous host molecule. The two weakly exchange-coupled quantum bits (target qubit blue and control qubit red) span four electron spin states. The electron spin transition is denoted by two black arrows.
The
full configuration interaction (full-CI) method is capable
of providing the numerically best wave functions and energies of atoms
and molecules within basis sets being used, although it is intractable
for classical computers. Quantum computers can perform full-CI calculations
in polynomial time against the system size by adopting a quantum phase
estimation algorithm (QPEA). In the QPEA, the preparation of initial
guess wave functions having sufficiently large overlap with the exact
wave function is recommended. The Hartree–Fock (HF) wave function
is a good initial guess only for closed shell singlet molecules and
high-spin molecules carrying no spin-β unpaired electrons, around
their equilibrium geometry, and thus, the construction of multiconfigurational
wave functions without performing post-HF calculations on classical
computers is highly desired for applying the method to a wide variety
of chemistries and physics. In this work, we propose a method to construct
multiconfigurational initial guess wave functions suitable for QPEA-based
full-CI calculations on quantum computers, by utilizing diradical
characters computed from spin-projected UHF wave functions. The proposed
approach drastically improves the wave function overlap, particularly
in molecules with intermediate diradical characters.
The SAC (symmetry adapted cluster)/SAC-CI method was used to calculate the ground and excited states of free base phthalocyanine (FBPc). This is the first accurate ab initio study of the excited states of FBPc. The calculated electronic spectrum agrees reasonably well with experimental results with regard to both energy and intensity. The relationships among the molecular structure, excitation energy, and spectral intensity are discussed, and the present results are compared with those for free base porphine (FBP) and free base tetrazaporphine (FBTAP) studied previously. Two important effects of skeletal changes are clarified; mesotetraaza substitution and tetrabenzo substitution cause a large splitting between the HOMO and next HOMO levels and lead to a breakdown of the quasi-degeneracy of the two main configurations of the Q band, resulting in strong visible absorption due to the incomplete cancellation of the individual contributions to the transition dipole moment. This explains why Pc's are so useful as pigments. Further, a new assignment of the B (Soret) band is proposed. The broad experimental B band is composed of at least four states. The main peak of the B band is due to transitions from the orbital lower than the so-called "four orbitals", and the transitions arising from the "four orbitals" constitute the shoulder in the lower energy side of the band.
The genes encoding the major putative rice plastidic translocators involved in the carbon flow related to starch metabolism were identified by exhaustive database searches. The genes identified were two for the triose phosphate/phosphate translocator (TPT), five for the glucose 6-phosphate/phosphate translocator (GPT) including putatively non-functional ones, four for the phosphoenolpyruvate/phosphate translocator (PPT), three for the putative ADP-glucose translocator (or Brittle-1 protein, BT1), two for the plastidic nucleotide transport protein (NTT), and one each for the plastidic glucose translocator (pGlcT) and the maltose translocator (MT). The expression patterns of the genes in various photosynthetic and non-photosynthetic organs were examined by quantitative real-time PCR. OsBT1-1 was specifically expressed in the seed and its transcript level tremendously increased at the onset of vigorous starch production in the endosperm, suggesting that the ADP-glucose synthesized in the cytosol is a major precursor for starch biosynthesis in the endosperm amyloplast. In contrast, all of the genes for OsTPT, OsPPT, and OsNTT were mainly expressed in source tissues, suggesting that their proteins play essential roles in the regulation of carbohydrate metabolism in chloroplasts. Substantial expression of the four OsGPT genes and the OspGlcT gene in both source and sink organs suggests that the transport of glucose phosphate and glucose is physiologically important in both photosynthetic and non-photosynthetic tissues. The present study shows that comprehensive analysis of expression patterns of the plastidic translocator genes is a valuable tool for the elucidation of the functions of the translocators in the regulation of starch metabolism in rice.
Quantum computers are capable to efficiently perform full configuration interaction (FCI) calculations of atoms and molecules by using the quantum phase estimation (QPE) algorithm. Because the success probability of the QPE depends on the overlap between approximate and exact wave functions, efficient methods to prepare accurate initial guess wave functions enough to have sufficiently large overlap with the exact ones are highly desired. Here, we propose a quantum algorithm to construct the wave function consisting of one configuration state function, which is suitable for the initial guess wave function in QPE-based FCI calculations of open-shell molecules, based on the addition theorem of angular momentum. The proposed quantum algorithm enables us to prepare the wave function consisting of an exponential number of Slater determinants only by a polynomial number of quantum operations.
Citrin plays a role in the transfer of NADHreducing equivalent from cytosol to mitochondria as part of the malate-aspartate shuttle in liver. Citrin deficiency may cause an impairment of glycolysis due to an increase in the cytosolic NADH/NAD ratio leading to an energy shortage in the liver. Mutations of the SLC25A13 gene are responsible for neonatal intrahepatic cholestasis (NICCD) and adult-onset type II citrullinemia (CTLN2). Most patients with NICCD show a resolution of symptoms within the first year of life, but some patients present with severe symptoms and require liver transplantation. We treated four patients including three siblings with NICCD by lactose (galactose)-restricted and medium-chain triglyceride (MCT)-supplemented formula. This formula rapidly improved the clinical condition and laboratory findings. Early treatment was more effective and did not require long-term administration. Lactose (galactose)-restriction can avoid further increase in the cytosolic NADH/NAD ratio in the liver and MCT supplementation can provide energy to hepatic cells by producing an excess of acetyl-CoA in mitochondria. Early treatment with lactose (galactose)-restricted and MCT-supplemented formula is recommended for patients with NICCD and possibly for patients with CTLN2.
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