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Two-dimensional (2D) semiconductors have recently attracted considerable attention due to their promising applications in future integrated electronic and optoelectronic devices. Large-scale synthesis of high-quality 2D semiconductors is an increasingly essential requirement for practical applications, such as sensing, imaging, and communications. In this work, homogeneous 2D GaTe films on a centimeter scale are epitaxially grown on fluorphlogopite mica substrates by molecular beam epitaxy (MBE). The epitaxial GaTe thin films showed an atomically 2D layered lattice structure with a T phase, which has not been discovered in the GaTe geometric isomer. Furthermore, semiconducting behavior and high mobility above room temperature were found in T-GaTe epitaxial films, which are essential for application in semiconducting devices. The T-GaTe-based photodetectors demonstrated respectable photodetection performance with a responsivity of 13 mA/W and a fast response speed. By introducing monolayer graphene as the substrate, we successfully realized high-quality GaTe/graphene heterostructures. The performance has been significantly improved, such as the responsivity was enhanced more than 20 times. These results highlight a feasible scheme for exploring the crystal phase of 2D GaTe and realizing the controlled growth of GaTe films on large substrates, which could promote the development of broadband, high-performance, and large-scale photodetection applications.

Non-fungible token (NFT) is a tradable unit of data stored on the blockchain which can be associated with some digital asset as a certification of ownership. The past several years have witnessed the exponential growth of the NFT market. In 2021, the NFT market reached its peak with more than $40 billion trades. Despite the booming NFT market, most NFT-related studies focus on its technical aspect, such as standards, protocols, and security, while our study aims at developing a pioneering recommender system for NFT buyers. In this paper, we introduce an extreme deep factorization machine (xDeepFM)-based recommender system, NFT.mine, which achieves real-time data collection, data cleaning, feature extraction, training, and inference. We used data from OpenSea, the most influential NFT trading platform, to testify the performance of NFT.mine. As a result, experiments showed that compared to traditional models such as logistic regression, naive Bayes, random forest, etc., NFT.mine outperforms them with higher AUC and lower cross entropy loss and outputs personalized recommendations for NFT buyers., Comment: 6 pages, 8 figures, 2 tables

The assumption of a uniform light color distribution is no longer applicable in scenes that have multiple light colors. Most color constancy methods are designed to deal with a single light color, and thus are erroneous when applied to multiple light colors. The spatial variability in multiple light colors causes the color constancy problem to be more challenging and requires the extraction of local surface/light information. Motivated by this, we introduce a multi-task learning method to discount multiple light colors in a single input image. To have better cues of the local surface/light colors under multiple light color conditions, we design a novel multi-task learning framework. Our framework includes auxiliary tasks of achromatic-pixel detection and surface-color similarity prediction, providing better cues for local light and surface colors, respectively. Moreover, to ensure that our model maintains the constancy of surface colors regardless of the variations of light colors, a novel local surface color feature preservation scheme is developed. We demonstrate that our model achieves 47.1% improvement (from 4.69 mean angular error to 2.48) compared to a state-of-the-art multi-illuminant color constancy method on a multi-illuminant dataset (LSMI)., Comment: 8 pages, 6 figures

Access to phosphoproteins with stoichiometric and site-specific phosphorylation status is key to understanding the role of protein phosphorylation. Here we report an efficient method to generate pure, active phosphotyrosine-containing proteins by genetically encoding a stable phosphotyrosine analog that is convertible to native phosphotyrosine. We demonstrate its general compatibility with proteins of various sizes, phosphotyrosine sites and functions, and reveal a possible role of tyrosine phosphorylation in negative regulation of ubiquitination.

Genetic predisposition to male breast cancer (MBC) is not well understood. The aim of this study was to better define the predisposition genes contributing to MBC and the utility of germline multi-gene panel testing (MGPT) for explaining the etiology of MBCs.Clinical histories and molecular results were retrospectively reviewed for 715 MBC patients who underwent MGPT from March 2012 to June 2016.The detection rate of MGPT was 18.1% for patients tested for variants in 16 breast cancer susceptibility genes and with no prior BRCA1/2 testing. BRCA2 and CHEK2 were the most frequently mutated genes (11.0 and 4.1% of patients with no prior BRCA1/2 testing, respectively). Pathogenic variants in BRCA2 [odds ratio (OR) = 13.9; p = 1.92 × 10-16], CHEK2 (OR = 3.7; p = 6.24 × 10-24), and PALB2 (OR = 6.6, p = 0.01) were associated with significantly increased risks of MBC. The average age at diagnosis of MBC was similar for patients with (64 years) and without (62 years) pathogenic variants. CHEK2 1100delC carriers had a significantly lower average age of diagnosis (n = 7; 54 years) than all others with pathogenic variants (p = 0.03). No significant differences were observed between history of additional primary cancers (non-breast) and family history of male breast cancer for patients with and without pathogenic variants. However, patients with pathogenic variants in BRCA2 were more likely to have a history of multiple primary breast cancers.These data suggest that all MBC patients regardless of age of diagnosis, history of multiple primary cancers, or family history of MBC should be offered MGPT.

Glycans play critical roles in a number of biological activities. Two common types of glycans, N-linked and O-linked, have been extensively analyzed in the last decades. N-glycans are typically released from glycoproteins by enzymes, while O-glycans are released from glycoproteins by chemical methods. It is important to identify and quantify both N- and O-linked glycans of glycoproteins to determine the changes of glycans. The effort has been dedicated to study glycans from ovarian cancer cells treated with O-linked glycosylation inhibitor qualitatively and quantitatively. We used a solid-phase chemoenzymatic approach to systematically identify and quantify N-glycans and O-glycans in the ovarian cancer cells. It consists of three steps: (1) immobilization of proteins from cells and derivatization of glycans to protect sialic acids; (2) release of N-glycans by PNGase F and quantification of N-glycans by isobaric tags; (3) release and quantification of O-glycans by β-elimination in the presence of 1-phenyl-3-methyl-5-pyrazolone (PMP). We used ovarian cancer cell lines to study effect of O-linked glycosylation inhibitor on protein glycosylation. Results suggested that the inhibition of O-linked glycosylation reduced the levels of O-glycans. Interestingly, it appeared to increase N-glycan level in a lower dose of the O-linked glycosylation inhibitor. The sequential release and analyses of N-linked and O-linked glycans using chemoenzymatic approach are a platform for studying N-glycans and O-glycans in complex biological samples. The solid-phase chemoenzymatic method was used to analyze both N-linked and O-linked glycans sequentially released from the ovarian cancer cells. The biological studies on O-linked glycosylation inhibition indicate the effects of O-glycosylation inhibition to glycan changes in both O-linked and N-linked glycan expression.

Access to phosphoproteins with stoichiometric and site-specific phosphorylation status is key to understanding the role of protein phosphorylation. Here we report an efficient method to generate pure, active phosphotyrosine-containing proteins by genetically encoding a stable phosphotyrosine analog that is convertible to native phosphotyrosine. We demonstrate its general compatibility with proteins of various sizes, phosphotyrosine sites and functions, and reveal a possible role of tyrosine phosphorylation in negative regulation of ubiquitination.

Genetic predisposition to male breast cancer (MBC) is not well understood. The aim of this study was to better define the predisposition genes contributing to MBC and the utility of germline multi-gene panel testing (MGPT) for explaining the etiology of MBCs.Clinical histories and molecular results were retrospectively reviewed for 715 MBC patients who underwent MGPT from March 2012 to June 2016.The detection rate of MGPT was 18.1% for patients tested for variants in 16 breast cancer susceptibility genes and with no prior BRCA1/2 testing. BRCA2 and CHEK2 were the most frequently mutated genes (11.0 and 4.1% of patients with no prior BRCA1/2 testing, respectively). Pathogenic variants in BRCA2 [odds ratio (OR) = 13.9; p = 1.92 × 10-16], CHEK2 (OR = 3.7; p = 6.24 × 10-24), and PALB2 (OR = 6.6, p = 0.01) were associated with significantly increased risks of MBC. The average age at diagnosis of MBC was similar for patients with (64 years) and without (62 years) pathogenic variants. CHEK2 1100delC carriers had a significantly lower average age of diagnosis (n = 7; 54 years) than all others with pathogenic variants (p = 0.03). No significant differences were observed between history of additional primary cancers (non-breast) and family history of male breast cancer for patients with and without pathogenic variants. However, patients with pathogenic variants in BRCA2 were more likely to have a history of multiple primary breast cancers.These data suggest that all MBC patients regardless of age of diagnosis, history of multiple primary cancers, or family history of MBC should be offered MGPT.

The mRNA display library provides a strategy to make up to 1013 unique peptides that fuse with their own genes via a covalent link. In this thesis, several strategies to prepare mRNA display libraries containing unnatural side chains are described. Chapter 1 is a short introduction and application of mRNA-display technology. Chapter 2 describes a chemical derivatization strategy to append an unnatural side chain to libraries. Chapter 2 introduces the incorporation of unnatural amino acids via non-sense codon suppression. Chapter 4 focuses on the catalytic selection with mRNA display libraries. These libraries should facilitate the discovery of novel ligands with functionalities beyond those provided by the 20 naturally occurring amino acids.

The mRNA display library provides a strategy to make up to 1013 unique peptides that fuse with their own genes via a covalent link. In this thesis, several strategies to prepare mRNA display libraries containing unnatural side chains are described. Chapter 1 is a short introduction and application of mRNA-display technology. Chapter 2 describes a chemical derivatization strategy to append an unnatural side chain to libraries. Chapter 2 introduces the incorporation of unnatural amino acids via non-sense codon suppression. Chapter 4 focuses on the catalytic selection with mRNA display libraries. These libraries should facilitate the discovery of novel ligands with functionalities beyond those provided by the 20 naturally occurring amino acids.

The mRNA display library provides a strategy to make up to 1013 unique peptides that fuse with their own genes via a covalent link. In this thesis, several strategies to prepare mRNA display libraries containing unnatural side chains are described. Chapter 1 is a short introduction and application of mRNA-display technology. Chapter 2 describes a chemical derivatization strategy to append an unnatural side chain to libraries. Chapter 2 introduces the incorporation of unnatural amino acids via non-sense codon suppression. Chapter 4 focuses on the catalytic selection with mRNA display libraries. These libraries should facilitate the discovery of novel ligands with functionalities beyond those provided by the 20 naturally occurring amino acids.

Glycan is an important class of macromolecules that play numerous biological functions. Quantitative glycomics - analysis of glycans at global level - however, is far behind genomics and proteomics owing to technical challenges associated with their chemical properties and structural complexity. As a result, technologies that can facilitate global glycan analysis are highly sought after. Here, we present QUANTITY (Quaternary Amine Containing Isobaric Tag for Glycan), a quantitative approach that can not only enhance detection of glycans by mass spectrometry, but also allow high-throughput glycomic analysis from multiple biological samples. This robust tool enabled us to accomplish glycomic survey of bioengineered Chinese Hamster Ovary (CHO) cells with knock-in/out enzymes involved in protein glycosylation. Our results demonstrated QUANTITY is an invaluable technique for glycan analysis and bioengineering.

Glycan is an important class of macromolecules that play numerous biological functions. Quantitative glycomics - analysis of glycans at global level - however, is far behind genomics and proteomics owing to technical challenges associated with their chemical properties and structural complexity. As a result, technologies that can facilitate global glycan analysis are highly sought after. Here, we present QUANTITY (Quaternary Amine Containing Isobaric Tag for Glycan), a quantitative approach that can not only enhance detection of glycans by mass spectrometry, but also allow high-throughput glycomic analysis from multiple biological samples. This robust tool enabled us to accomplish glycomic survey of bioengineered Chinese Hamster Ovary (CHO) cells with knock-in/out enzymes involved in protein glycosylation. Our results demonstrated QUANTITY is an invaluable technique for glycan analysis and bioengineering.

The environmental background scattering and unstable low energy component of bremsstrahlung spectra often distort the half-value layer (HVL) measurements using conventional detectors. Here we demonstrate that a Cerenkov detector with a detection threshold in the low energy range can successfully reduce the effect of these systematic errors and improve the sensitivity of the HVL measurements. Our experiments are conducted on a system based on a dual-energy electron linac. Comparing the results obtained by a Cerenkov detector and those by a CsI(Tl) detector shows the robustness of the Cerenkov detector. Moreover, the energy response calculation also shows that the Cerenkov detector is more sensitive to the quality of the bremsstrahlung spectra than the CsI(Tl) detector. (C) 2011 Elsevier Ltd. All rights reserved.

The environmental background scattering and unstable low energy component of bremsstrahlung spectra often distort the half-value layer (HVL) measurements using conventional detectors. Here we demonstrate that a Cerenkov detector with a detection threshold in the low energy range can successfully reduce the effect of these systematic errors and improve the sensitivity of the HVL measurements. Our experiments are conducted on a system based on a dual-energy electron linac. Comparing the results obtained by a Cerenkov detector and those by a CsI(Tl) detector shows the robustness of the Cerenkov detector. Moreover, the energy response calculation also shows that the Cerenkov detector is more sensitive to the quality of the bremsstrahlung spectra than the CsI(Tl) detector. (C) 2011 Elsevier Ltd. All rights reserved.

The environmental background scattering and unstable low energy component of bremsstrahlung spectra often distort the half-value layer (HVL) measurements using conventional detectors. Here we demonstrate that a Cerenkov detector with a detection threshold in the low energy range can successfully reduce the effect of these systematic errors and improve the sensitivity of the HVL measurements. Our experiments are conducted on a system based on a dual-energy electron linac. Comparing the results obtained by a Cerenkov detector and those by a CsI(Tl) detector shows the robustness of the Cerenkov detector. Moreover, the energy response calculation also shows that the Cerenkov detector is more sensitive to the quality of the bremsstrahlung spectra than the CsI(Tl) detector. (C) 2011 Elsevier Ltd. All rights reserved.