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Quantum computing for real world applications requires large arrays of qubits. This requires advanced integration technologies. In this work, we propose a simple integration method with fine interconnect pitch (10 μm) and close spacing that can overcome the large input and output (I/O) and high wiring level requirements of very large scale of quantum circuits. A system-on-wafer (SoW) packaging concept called superconducting silicon interconnect fabric (superconducting-IF), based on silicon interconnect fabric (Si-IF), is proposed, with the help of a Au interlayer technology onto the superconducting-IF. The fine-pitch and die-to-wafer-scale Au interlayer is the first demonstration of direct metal-metal thermocompression bonding (TCB) that is optimized for superconducting applications without the use of solders. The developed Au interlayer integration technology is demonstrated to be Josephson-junction-compatible (30 MPa), and electrically reliable down to 2 K. The mechanical strength of the Au interlayer integration method is optimized through shear tests with a shear force around 150 N on 2 2 mm2 dies. The transition temperature (Tc) of Nb, which is at 9 K, is experimentally verified to be unchanged after each fabrication process. Electrical and temperature cycling measurements on over 20 bonded dies of large-pitch Kelvin structures as well as fine-pitch daisy chain structures reveal reliable connections in the low-temperature regime. This work pushes quantum computing a step closer to realize its potential through 3D integration of a very large scale of quantum circuits with a high density of I/O (>10 000 per mm2) as well as high wiring capability and without introducing lossy amorphous dielectrics.

C19H25N5O, monoclinic, P21 (no. 4), a = 16.0600(2) Å, b = 5.3992(1) Å, c = 19.8514(2) Å, β = 94.260(1)°, V = 1716.58(4) Å3, Z = 4, Rgt (F) = 0.0350, wRref(F2) = 0.0908, T = 100.00(10) K.

Background: Biannual Ultrasound showed insufficient sensitivity in detecting small or early-stage hepatocellular carcinoma (HCC). Abbreviated magnetic resonance imaging (A-MRI) protocols with fewer sequences demonstrated higher HCC detection sensitivity than ultrasound with acceptable cost and examination time. Purpose: To compare the diagnostic performance of gadoxetic acid-enhanced A-MRI with a full sequence MRI (F-MRI) protocol for small HCC (≤2 cm) in cirrhotic or hepatitis B virus-infected high-risk patients. Material and Methods: Two hundred and four consecutive patients with 166 pathologically confirmed small HCC who underwent preoperative gadoxetic acid-enhanced MRI were retrospectively included. A-MRI set comprised T1-weighted hepatobiliary phase imaging, T2-weighted imaging, diffusion-weighted imaging and apparent diffusion coefficient mapping. Two independent radiologists blinded to clinical data assessed the A-MRI set and F-MRI set. Per-patient HCC and per-lesion HCC diagnostic performance were compared. Results: Per-patient HCC detection sensitivity of A-MRI set was 93.8% and 91.2% for observer 1 and observer 2, and, for the F-MRI set, the per-patient HCC detection sensitivity was 96.6% and 95.2%, respectively. There was no significant difference in per-patient sensitivity, specificity and per-lesion HCC detection sensitivity between the two imaging sets for both readers. (P = 0.06–0.25) The A-MRI set showed higher sensitivity on HCC without arterial phase hyperenhancement, and the F-MRI set demonstrated with higher sensitivity on HCC with arterial phase hyperenhancement (P < 0.05). Conclusion: A-MRI using diagnostic criteria including hypointensity on hepatobiliary phase plus mild to moderate hyperintensity on T2-weighted imaging or restricted diffusion demonstrated comparable sensitivity and specificity for small HCC compared to the F-MRI protocol in high-risk patients. [ABSTRACT FROM AUTHOR]

Background: Gadoxetic acid-enhanced magnetic resonance imaging (MRI) has been widely used in clinical practice. However, scientific evidence is lacking for recommending a particular sequence for measuring tumor size. Purpose: To retrospectively compare the size of hepatocellular carcinoma (HCC) measured on different gadoxetic acid-enhanced MRI sequences using pathology as a reference. Material and Methods: A total of 217 patients with single HCC who underwent gadoxetic acid-enhanced MRI before surgery were included. The size of the HCC was measured by two abdominal radiologists independently on the following sequences: T1-weighted; T2-weighted; b-500 diffusion-weighted imaging (DWI); and arterial, portal venous, transitional, and hepatobiliary phases. Tumor size measured on MRI was compared with pathological size by using Pearson correlation coefficient, independent-sample t test, and Bland–Altman plot. Agreement between two readers was evaluated with intraclass correlation coefficient (ICC). Results: Correlation between the MR images and pathology was high for both readers (0.899–0.955). Absolute error between MRI and pathologic assessment was lowest on hepatobiliary phase images for both readers (reader 1, 2.8±4.2 mm; reader 2, 3.2±3.4 mm) and highest on arterial phase images for reader 1 (4.9±4.4 mm) and DWI phase images for reader 2 (5.1±4.9 mm). Absolute errors were significantly different for hepatobiliary phase compared with other sequences for both readers (reader 1, P ≤0.012; reader 2, P ≤0.037). Inter-reader agreements for all sequence measurements were strong (0.971–0.997). Conclusion: The performance of gadoxetic acid-enhanced MRI sequences varied with HCC size, and the hepatobiliary phase may be optimal among these sequences. [ABSTRACT FROM AUTHOR]

C19H25N5O, monoclinic, P21 (no. 4), a = 16.0600(2) Å, b = 5.3992(1) Å, c = 19.8514(2) Å, β = 94.260(1)°, V = 1716.58(4) Å3, Z = 4, Rgt (F) = 0.0350, wRref(F2) = 0.0908, T = 100.00(10) K. [ABSTRACT FROM AUTHOR]