Two-qubit pure state tomography by five product orthonormal bases

In this paper, we focus on two-qubit pure state tomography. For an arbitrary unknown two-qubit pure state, separable or entangled, it has been found that the measurement probabilities of 16 projections onto the tensor products of Pauli eigenstates are enough to uniquely determine the state. Moreover, these corresponding product states are arranged into five orthonormal bases. We design five quantum circuits, which are decomposed into the common gates in universal quantum computation, to simulate the five projective measurements onto these bases. At the end of each circuit, we measure each qubit with the projective measurement {｜0〉〈0 ｜,｜1〉,〈1｜ }. Then, we consider the open problem whether three orthonormal bases are enough to distinguish all two-qubit pure states. A necessary condition is given. Suppose that there are three orthonormal bases {B1,B2,B3}. Denote the unitary transition matrices from B1 to {B2,B3 } as U1 and U2. All 32 elements of matrices U1 and U2 should not be zero. If not, these three bases cannot distinguish all two-qubit pure states.

Research Progress on Pathogenesis and Intervention Measures of Depression

With the wide spread of the epidemic,the long-term closed lifestyle and the sharp reduction of physical activities,many people have mental health problems such as panic,anxiety and depression.At present,there are few studies on the effect of exercise on depression.Therefore,the study selected exercise intervention therapy and other intervention methods to evaluate the intervention effect of depression,and explored the effect of exercise intervention by evaluating depression scale and effective indicators.Hope this can provide a new idea for exercise intervention as an adjunctive therapy for depression on drug treatment.

Reciprocal inhibition of expression between RAV1 and BES1 modulates plant growth and development in Arabidopsis

RAV1(Related to ABI3/VP1)is a plant-specific B3 and AP2 domain-containing transcription factor that acts as a negative regulator of growth in many plant species.The expression of RAV1 is downregulated by brassinosteroids(BRs);large-scale transcriptome analyses have shown that the expression of RAV1 was previously targeted by BRI1-EMS-SUPPRESOR1(BES1)and BRASSINAZOLE-RESISTANT1(BZR1),which are critical transcription factors for the BR-signaling process.Using RAV1-overexpressing transgenic plants,we showed that RAV1 overexpression reduced the BR signaling capacity,resulting in the downregulation of BR biosynthetic genes and BES1 expression.Furthermore,we demonstrated that BES1,not BZR1,is directly bound to the RAV1 promoter and repressed RAV1 expression,and vice versa;RAV1 is also bound to the BES1 promoter and repressed BES1 expression.This mutual inhibition was specific to RAV1 and BES1 because RAV1 exhibited binding activity to the BZR1 promoter but did not repress BZR1 expression.We observed that constitutively activated BR signaling phenotypes in bes1-D were attenuated by the repression of endogenous BES1 expression in transgenic bes1-D plants overexpressing RAV1.RNA-sequencing analysis of RAV1-overexpressing transgenic plants and bes1-D mutant plants revealed differentially expressed genes by RAV1 and BES1 and genes that were oppositely co-regulated by RAV1 and BES1.RAV1 and BES1 regulated different transcriptomes but co-regulated a specific set of genes responsible for the balance between growth and defense.These results suggested that the mutual inhibitory transcriptional activities of RAV1 and BES1 provide fine regulatory mechanisms for plant growth and development.

BRI1-Associated Receptor Kinase 1 Regulates Guard Cell ABA Signaling Mediated by Open Stomata 1 in Arabidopsis

Stomatal movements are critical in regulating gas exchange for photosynthesis and water balance between plant tissues and the atmosphere. The plant hormone abscisic acid （ABA） plays key roles in regulating stomatal closure under various abiotic stresses. In this study, we revealed a novel role of BAKI in guard cell ABA signaling. We found that the brassinosteroid （BR） signaling mutant bakl lost more water than wild- type plants and showed ABA insensitivity in stomatal closure. ABA-induced OST1 expression and reactive oxygen species （ROS） production were also impaired in bakl. Unlike direct treatment with H202, overex-pression of OST1 did not completely rescue the insensitivity of bakl to ABA. We demonstrated that BAK1 forms a complex with OST1 near the plasma membrane and that the BAKI/OST1 complex is increased in response to ABA in planta. Brassinolide, the most active BR, exerted a negative effect on ABA-induced formation of the BAK1/OST1 complex and OST1 expression. Moreover, we found that BAK1 and ABI1 oppositely regulate OST1 phosphorylation in vitro, and that ABI1 interacts with BAK1 and inhibits the interaction of BAK1 and OST1. Taken together, our results suggest that BAK1 regulates ABA-induced stomatal closure in guard cells.