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1.
Nature ; 630(8015): 70-76, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38811730

ABSTRACT

Colour centres in diamond have emerged as a leading solid-state platform for advancing quantum technologies, satisfying the DiVincenzo criteria1 and recently achieving quantum advantage in secret key distribution2. Blueprint studies3-5 indicate that general-purpose quantum computing using local quantum communication networks will require millions of physical qubits to encode thousands of logical qubits, presenting an open scalability challenge. Here we introduce a modular quantum system-on-chip (QSoC) architecture that integrates thousands of individually addressable tin-vacancy spin qubits in two-dimensional arrays of quantum microchiplets into an application-specific integrated circuit designed for cryogenic control. We demonstrate crucial fabrication steps and architectural subcomponents, including QSoC transfer by means of a 'lock-and-release' method for large-scale heterogeneous integration, high-throughput spin-qubit calibration and spectral tuning, and efficient spin state preparation and measurement. This QSoC architecture supports full connectivity for quantum memory arrays by spectral tuning across spin-photon frequency channels. Design studies building on these measurements indicate further scaling potential by means of increased qubit density, larger QSoC active regions and optical networking across QSoC modules.

2.
J Prosthodont Res ; 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38479888

ABSTRACT

PATIENTS: This case report presents a minimally invasive approach to replace a missing mandibular lateral incisor using a dual-injection molding technique with flowable composite resins. Integrated with a comprehensive digital workflow, this method achieves a structurally and esthetically biomimetic, bi-layered prosthetic solution. A 34-year-old woman with congenital absence of a mandibular lateral incisor was successfully rehabilitated using a direct composite resin-bonded fixed partial denture (RBFPD). DISCUSSION: Two specialized three-dimensional (3D)-printed flexible indices stabilized by a custom-designed 3D-printed rigid holder were employed to ensure the meticulous injection molding of flowable composite resins formulated to emulate the inherent chromatic gradations between dentin and enamel. The inherent flexibility of the indices, combined with the holder, facilitated accurate and seamless adaptation to the complex morphological features of the dental arch, thereby mitigating the challenges commonly associated with rigid 3D-printed resin indices. CONCLUSIONS: The bilayered direct composite RBFPD using 3D printed flexible indices prepared with a full digital workflow has several advantages over other dental prosthetic solutions, including noninvasiveness, cost-effectiveness, biomimetic esthetics, repairability, and shortened treatment times. Although the initial results are promising, further longitudinal studies with larger patient cohorts are required to confirm the long-term efficacy of this approach.

3.
Antonie Van Leeuwenhoek ; 117(1): 31, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38319408

ABSTRACT

An endophytic actinobacterium, designated strain HUAS 5T, was isolated from the root tissue of Cathaya argyrophylla collected in Chenzhou city of Hunan Province, PR China. This strain produced grey aerial mycelium that differentiated into spiral spore chains with spiny-surfaced ellipsoidal spores on Gause's synthetic No. 1 medium. Strain HUAS 5T grew well on Gause's synthetic No. 1, Reasoner'2 and ISP serial media. This strain grew at 15-40 °C (optimum, 28 °C), pH 6.0-9.0 (optimum, pH 7.0) and in presence of 0-5.0% (w/v) NaCl. The predominant cellular fatty acids of strain HUAS 5T (> 5.0%) were iso-C16:0, iso-C14:0, anteiso-C15:0, iso-C15:0, C16:0, iso-C16:1 H and Sum in Feature 3 (C16:1 ω7c/C16:1 ω6c). Sequence analysis of the 16S rRNA gene indicated that this strain belonged to the genus Streptomyces and exhibited highest sequence similarity to Streptomyces hirsutus NRRL B-2713T (97.3%), which is much less than 98.7% cut-off point of species definitions for bacteria and archaea. Phylogenetic analysis of 16S rRNA gene sequence and whole genome indicated that strain HUAS 5T formed an independent lineage, which suggested that it belonged to a potential novel species. Based on the morphological, cultural, physio-biochemical properties and chemotaxonomy, strain HUAS 5T (= MCCC 1K08552T = JCM 36055T) is deemed to represent a novel Streptomyces species, for which we put forward the name Streptomyces cathayae sp. nov.


Subject(s)
Archaea , Streptomyces , Phylogeny , RNA, Ribosomal, 16S/genetics , China , Streptomyces/genetics
4.
Se Pu ; 40(3): 224-233, 2022 Mar 08.
Article in Chinese | MEDLINE | ID: mdl-35243832

ABSTRACT

Protein complexes are involved in a variety of biological activities. Accurate and comprehensive characterization of the structures and interactions of protein complexes is crucial in determining their biological functions. Chemical cross-linking coupled with mass spectrometry (CXMS) is an emerging investigative technique for protein complexes. CXMS enables the sensitive high-throughput analysis of protein complexes without the requirements of molecular weight and purification. These attributes have spurred the increased use of CXMS for the structure and interaction characterization of purified protein complexes and complicated cell lysate samples. CXMS utilizes chemical cross-linking reagents to covalently connect two reactive amino acids in or between proteins that are spatially close to each other. Subsequently, the cross-linked proteins are digested into cross-linked peptides, followed by LC-MS/MS analysis, as well as database searching to provide cross-linking information for the composition, interaction, and structural site distance restrictions of protein complex identification. Therefore, identification of cross-linked sites has a decisive influence on the characterization of protein complexes. This identification is limited by the unsatisfactory quality of the cross-linked peptide spectrum. Insufficient b/y fragment ions and poor continuity of amino acid sequence matching lead to low coverage and accuracy of cross-linked site identification. Based on the complementary feature of mirror-cutting digestion, an orthogonal digestion strategy based on LysargiNase combined with trypsin was developed in this study. Trypsin is the most commonly utilized digestion enzyme in proteomics, with extremely high enzyme activity and specificity. Trypsin generates C-terminally charged peptides after lysine (K) and arginine (R). LysargiNase is a mirror protease complementary to trypsin that cleaves before the K and R residues. This generates peptides with an N-terminal positively-charged residue. Owing to the different physical and chemical micro-environments of the cross-linked peptides digested by LysargiNase and trypsin, the behavior of their detection ability in MS analysis is diverse. Using the orthogonal digestion strategy, both simple and complicated cross-linked samples were analyzed in this study. For the analysis of bovine serum albumin (BSA), 291 pairs of non-redundant cross-linked sites were obtained, of which 216 pairs of cross-linked sites were provided by trypsin digestion, whereas 75 pairs of cross-linked sites were exclusively supplied by LysargiNase digestion. Except for the 35% increase in the number of identified cross-linked sites, 32% of the spectra of the commonly identified cross-linked peptides have better quality with more b-type fragment ions and consecutive sequence matching. Furthermore, for the Escherichia coli sample, 726 pairs of cross-linked sites were obtained in total, among which, 624 and 274 pairs were identified from trypsin and LysargiNase digestion, respectively. LysargiNase digestion yielded 120 individual cross-linked sites, which resulted in a 16% increase in single trypsin digestion. Consistent with the BSA sample, the quality was improved in 35% of the spectra of commonly identified cross-linked peptides. Corresponding to the identified cross-linked peptides, 242 structural constraints with 607 pairs of intra-cross-linked sites and 29 sets of protein-protein interactions with 119 pairs of inter-cross-linked sites were obtained. The collective results demonstrated that, mirror cutting-assisted orthogonal digestion strategy could significantly increase the number of identified fragment ions and amino acid sequences matching the continuity of the spectra by contributing b-and y-type ions, respectively. This improved the accuracy and coverage of cross-linked peptide identification. The findings additionally demonstrate the superiority of our method in the accurate identification of the cross-linked peptide spectra and the increased number of identified cross-linked sites. In a word, this method is expected to provide new insights for the large-scale and highly accurate characterization of protein complexes.


Subject(s)
Proteomics , Tandem Mass Spectrometry , Chromatography, Liquid , Digestion , Proteomics/methods , Tandem Mass Spectrometry/methods , Trypsin/chemistry , Trypsin/metabolism
5.
Materials (Basel) ; 13(1)2020 Jan 03.
Article in English | MEDLINE | ID: mdl-31947788

ABSTRACT

The authors thank Rui Neves for his discussions related to our work. Errors in the formula have been corrected as suggested by the discusser and data in the article have also been revised.

6.
Materials (Basel) ; 12(14)2019 Jul 12.
Article in English | MEDLINE | ID: mdl-31336841

ABSTRACT

The deterioration of soil-cement in a saline environment leads to a reduction in strength and an increase in permeability. Effective methods of determining the deteriorated layer permeability coefficient of soil-cement are currently lacking. A laboratory test method for measuring the permeability coefficient of the deteriorated layer was proposed using the modified permeability coefficient testing apparatus. According to the proposed method, the permeability coefficient of the deteriorated layer could be obtained after testing the permeability coefficient of the soil-cement specimen in acuring room and testing the equivalent permeability coefficient and deterioration depth of the soil-cement specimen in a deteriorated environment. Using the marine dredger fill from Jiaozhou Bay as a case study, the deteriorated layer permeability coefficients of soil-cements with different cement contents were tested. It turned out that the permeability of the deteriorated layer increases with age. At the beginning of the curing age, higher cement content led to a smaller permeability coefficient of the deteriorated layer of soil-cement. As the curing age increased, the deteriorated layer permeability coefficient of the soil-cement with higher cement content increased. The evolution of the permeability coefficient of a deteriorated layer with age can be formulated as the Logistic function. This study provides support for anti-permeability designs of soil-cement structures in saline environments.

7.
IEEE Trans Biomed Circuits Syst ; 12(3): 709-721, 2018 06.
Article in English | MEDLINE | ID: mdl-29877833

ABSTRACT

Millimeter-wave/terahertz rotational spectroscopy of polar gaseous molecules provides a powerful tool for complicated gas mixture analysis. In this paper, a 220-to-320-GHz dual-frequency-comb spectrometer in 65-nm bulk CMOS is presented, along with a systematic analysis on fundamental issues of rotational spectrometer, including the impacts of various noise mechanisms, gas cell, molecular properties, detection sensitivity, etc. Our comb spectrometer, based on a high-parallelism architecture, probes gas sample with 20 comb lines simultaneously. It does not only improve the scanning speed by 20, but also reduces the overall energy consumption to 90 mJ/point with 1 Hz bandwidth (or 0.5 s integration time). With its channelized 100-GHz scanning range and sub-kHz specificity, wide range of molecules can be detected. In the measurements, state-of-the-art total radiated power of 5.2 mW and single sideband noise figure of 14.6-19.5 dB are achieved, which further boost the scanning speed and sensitivity. Finally, spectroscopic measurements for carbonyl sulfide (OCS) and acetonitrile (CH CN) are presented. With a path length of 70 cm and 1 Hz bandwidth, the measured minimum detectable absorption coefficient reaches  cm. For OCS that enables a minimum detectable concentration of 11 ppm. The predicted sensitivity for some other molecules reaches ppm level (e.g., 3 ppm for hydrogen cyanide), or 10 ppt level if gas preconcentration with a typical gain of 10 is used.


Subject(s)
Acetonitriles/analysis , Gases/analysis , Sulfur Oxides/analysis , Terahertz Spectroscopy/instrumentation , Terahertz Spectroscopy/methods , Sensitivity and Specificity
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