Analytical formulation of the second-order derivative of energy for orbital-optimized variational quantum eigensolver: application to polarizability

We develop a quantum-classical hybrid algorithm to calculate the analytical second-order derivative of the energy for the orbital-optimized variational quantum eigensolver (OO-VQE), which is a method to calculate eigenenergies of a given molecular Hamiltonian by utilizing near-term quantum computers and classical computers. We show that all quantities required in the algorithm to calculate the derivative can be evaluated on quantum computers as standard quantum expectation values without using any ancillary qubits. We validate our formula by numerical simulations of quantum circuits for computing the polarizability of the water molecule, which is the second-order derivative of the energy with respect to the electric field. Moreover, the polarizabilities and refractive indices of thiophene and furan molecules are calculated as a testbed for possible industrial applications. We finally analyze the error-scaling of the estimated polarizabilities obtained by the proposed analytical derivative versus the numerical one obtained by the finite difference. Numerical calculations suggest that our analytical derivative may require fewer measurements (runs) on quantum computers than the numerical derivative to achieve the same fixed accuracy.Comment: 34 + 4 page

ADAPT-QSCI: Adaptive Construction of Input State for Quantum-Selected Configuration Interaction

We present a quantum-classical hybrid algorithm for calculating the ground state and its energy of the quantum many-body Hamiltonian by proposing an adaptive construction of a quantum state for the quantum-selected configuration interaction (QSCI) method. QSCI allows us to select important electronic configurations in the system to perform CI calculation (subspace diagonalization of the Hamiltonian) by sampling measurement for a proper input quantum state on a quantum computer, but how we prepare a desirable input state has remained a challenge. We propose an adaptive construction of the input state for QSCI in which we run QSCI repeatedly to grow the input state iteratively. We numerically illustrate that our method, dubbed \textit{ADAPT-QSCI}, can yield accurate ground-state energies for small molecules, including a noisy situation for eight qubits where error rates of two-qubit gates and the measurement are both as large as 1\%. ADAPT-QSCI serves as a promising method to take advantage of current noisy quantum devices and pushes forward its application to quantum chemistry.Comment: 14 page

Photoacoustic mammography capable of simultaneously acquiring photoacoustic and ultrasound images

We have constructed a prototype photoacoustic mammography system (PAM-02) capable of simultaneously acquiring photoacoustic (PA) and ultrasound (US) images. Each PA, US, and fused PA/US image can be acquired over a wide area of the breast using the scanning module of a US transducer, a PA detector, and optical prisms. The resolution of the PA images exhibits improvement from 2 to 1 mm compared to images acquired using our previous prototype. The maximum scan area of PAM-02 is 90 mm along the horizontal axis and 150 mm along the vertical axis. In a phantom experiment, the available depth was at least 45 mm. A representative example of the application of the PAM-02 prototype in clinical research at Kyoto University is presented and shows S-factor images, which are considered an approximation parameter related to hemoglobin saturation of tumor-related blood vessels. We confirmed the applicability of the system for anatomical and biological research

An Integrative Analysis to Identify Driver Genes in Esophageal Squamous Cell Carcinoma

<div><p>Background</p><p>Few driver genes have been well established in esophageal squamous cell carcinoma (ESCC). Identification of the genomic aberrations that contribute to changes in gene expression profiles can be used to predict driver genes.</p><p>Methods</p><p>We searched for driver genes in ESCC by integrative analysis of gene expression microarray profiles and copy number data. To narrow down candidate genes, we performed survival analysis on expression data and tested the genetic vulnerability of each genes using public RNAi screening data. We confirmed the results by performing RNAi experiments and evaluating the clinical relevance of candidate genes in an independent ESCC cohort.</p><p>Results</p><p>We found 10 significantly recurrent copy number alterations accompanying gene expression changes, including loci 11q13.2, 7p11.2, 3q26.33, and 17q12, which harbored <i>CCND1</i>, <i>EGFR</i>, SOX2, and <i>ERBB2</i>, respectively. Analysis of survival data and RNAi screening data suggested that <i>GRB7</i>, located on 17q12, was a driver gene in ESCC. In ESCC cell lines harboring 17q12 amplification, knockdown of <i>GRB7</i> reduced the proliferation, migration, and invasion capacities of cells. Moreover, siRNA targeting <i>GRB7</i> had a synergistic inhibitory effect when combined with trastuzumab, an anti-<i>ERBB2</i> antibody. Survival analysis of the independent cohort also showed that high <i>GRB7</i> expression was associated with poor prognosis in ESCC.</p><p>Conclusion</p><p>Our integrative analysis provided important insights into ESCC pathogenesis. We identified <i>GRB7</i> as a novel ESCC driver gene and potential new therapeutic target.</p></div

Results of analysis on RNA interference screening data of Project Achilles.

<p>Results of analysis on RNA interference screening data of Project Achilles.</p

Knockdown of <i>GRB7</i> expression in ESCC cell lines.

<p>(a) Reductions in mRNA and protein levels of GRB7 at 48 hours after siRNA transfection in KYSE410 and TE4 cells. The results are the mean ± SD from 3 replicates of a single experiment. (b) <i>GRB7</i> inactivation reduced proliferation of KYSE410 and TE4 cells. Cell growth was measured on days 2, 3, and 4 by MTT assay. Absorbance at day 0 was assigned a value of 1. The results are the mean ± SD from 6 replicates of a single experiment. (c) Migration and invasion assays using <i>GRB7</i>-knockdown cells. Each bar represents the average of 3 measurements. (d) Inhibitory effects of siRNA targeting <i>GRB7</i> in combination with trastuzumab. Cells were transfected with siRNA targeting <i>GRB7</i> or negative control siRNA and treated with or without trastuzumab (0.1 and 1.0 μg/mL). Cells were then seeded in 96-well plates, and cell growth was monitored every 24 hours using MTT assays. Absorbance at day 0 was assigned a value of 1. The results are the mean ± SD from 6 replicates of a single experiment.</p