In-situ cosmogenic ³⁶Cl denudation rates of carbonates in Guizhou karst area

This study quantifies surface denudation of carbonate rocks by the first application of in-situ cosmogenic <sup>36</sup>Cl in China. Concentrations of natural Cl and in-situ cosmogenic <sup>36</sup>Cl in bare carbonates from Guizhou karst areas were measured with isotope dilution by accelerator mass spectrometer. The Cl concentration varied from 16 to 206 ppm. The <sup>36</sup>Cl concentrations were in range of (0.8–2.4)×106 atom g−1, resulting in total denudation rates of 20–50 mm ka−1 that averaged over a 104–105 a timescale. The <sup>36</sup>Cl-denudation rates showed roughly a negative correlation with the local mean temperature. This preliminary observation may suggest the variations of proportions of chemical weathering and physical erosion in denudation process, depending upon local climatic conditions

Experimental realization of optimal asymmetric cloning and telecloning via partial teleportation

We report an experimental realization of both optimal asymmetric cloning and telecloning of single photons by making use of partial teleportation of an unknown state. In the experiment, we demonstrate that, conditioned on the success of partial teleportation of single photons, not only the optimal asymmetric cloning can be accomplished, but also one of two outputs can be transfered to a distant location, realizing the telecloning. The experimental results represent a novel way to achieve the quantum cloning and may have potential applications in the context of quantum communication.Comment: 4 pages and 4 figure

Expression of the microRNA-143/145 cluster is decreased in hepatitis B virus-associated hepatocellular carcinoma and may serve as a biomarker for tumorigenesis in patients with chronic hepatitis B

The aims of the present study were to identify the expression profile of microRNA (miR)‑143/145 in hepatitis B virus (HBV)‑associated hepatocellular carcinoma (HCC), explore its association with prognosis and investigate whether the serum miR‑143/145 expression levels may serve as a diagnostic indicator of HBV‑associated HCC. The microRNA (miRNA) chromatin immunoprecipitation dataset was obtained from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus databases, and analyzed using the Wilcoxon signed‑rank test. It was observed that the expression of miR‑143 and miR‑145 was decreased 1.5‑fold in HBV‑associated HCC samples compared with non‑tumor tissue in the TCGA and the GSE22058 datasets (P\u3c0.01). Using the reverse transcription‑quantitative polymerase chain reaction, it was further confirmed that miR‑143/145 and their host gene MIR143HG were downregulated in HBV‑associated HCC tissues compared with corresponding distal non‑tumor tissues. The lower level of miR‑143 and miR‑145 expression was associated with tumor differentiation, and may thus be responsible for a poor prognosis of patients with HBV‑associated HCC. The receiver‑operating characteristic (ROC) curves were used to explore the potential value of miR‑143 and miR‑145 as biomarkers for predicting HBV‑associated HCC tumorigenesis. In serum, miR‑143/145 were identified to be significantly decreased in patients with HBV‑associated HCC compared with negative control patients, and their associated areas under the ROC curves were calculated at 0.813 and 0.852 (P\u3c0.05), with each having a sensitivity and a specificity close to 0.80. These results indicated that the decreased expression of the miR‑143/145 cluster and their host gene MIR143HG in HBV‑associated HCC tissue was associated with prognosis, and each of these miRNAs may serve as a valuable diagnostic biomarker for predicting HBV‑associated HCC tumorigenesis

Practice with Graph-based ANN Algorithms on Sparse Data: Chi-square Two-tower model, HNSW, Sign Cauchy Projections

Sparse data are common. The traditional ``handcrafted'' features are often sparse. Embedding vectors from trained models can also be very sparse, for example, embeddings trained via the ``ReLu'' activation function. In this paper, we report our exploration of efficient search in sparse data with graph-based ANN algorithms (e.g., HNSW, or SONG which is the GPU version of HNSW), which are popular in industrial practice, e.g., search and ads (advertising). We experiment with the proprietary ads targeting application, as well as benchmark public datasets. For ads targeting, we train embeddings with the standard ``cosine two-tower'' model and we also develop the ``chi-square two-tower'' model. Both models produce (highly) sparse embeddings when they are integrated with the ``ReLu'' activation function. In EBR (embedding-based retrieval) applications, after we the embeddings are trained, the next crucial task is the approximate near neighbor (ANN) search for serving. While there are many ANN algorithms we can choose from, in this study, we focus on the graph-based ANN algorithm (e.g., HNSW-type). Sparse embeddings should help improve the efficiency of EBR. One benefit is the reduced memory cost for the embeddings. The other obvious benefit is the reduced computational time for evaluating similarities, because, for graph-based ANN algorithms such as HNSW, computing similarities is often the dominating cost. In addition to the effort on leveraging data sparsity for storage and computation, we also integrate ``sign cauchy random projections'' (SignCRP) to hash vectors to bits, to further reduce the memory cost and speed up the ANN search. In NIPS'13, SignCRP was proposed to hash the chi-square similarity, which is a well-adopted nonlinear kernel in NLP and computer vision. Therefore, the chi-square two-tower model, SignCRP, and HNSW are now tightly integrated

Characterization of stress degradation products of curcumin and its two derivatives by UPLC–DAD–MS/MS

AbstractCurcumin and its two derivatives of PB-3 and DY-1 were subjected to the forced degradation studies under the conditions of hydrolysis (acidic and alkaline), oxidation, photolysis, and thermal stress recommended by ICH Q1A (R2) by means of UPLC–DAD–MS/MS. Three analytes and their degradation products were separated on a column of ACQUITY UPLC®BEH C18 (100mm×2.1mm, 1.7μm) with an in-line filter prior to the column using acetonitrile and 10mM ammonium acetate buffer (pH adjusted to 3.5) as a mobile phase. Both curcumin and DY-1 showed extensive degradation under alkaline condition and gave rise to two degradation products for curcumin and three for DY-1, respectively, while no degradation product was observed under other tested conditions. PB-3 was found to be unstable in acid and alkaline conditions, two degradation products in acidic hydrolytic condition and one in alkaline condition were obtained, while it was stable in photolytic, oxidative and thermal stress conditions. The degradation products of three analytes were characterized as follows by analyzing the mass fragmentation patterns of curcumin and mass analysis of the degradation products: ferulic acid and vanillin for curcumin, 3-methoxyl-4-[3-(1-tetrahydropyrrolyl)propoxyl] benzoic aldehyde, 2,2-di-(1-phenylmethyl)-3-oxo-5-[3-methoxyl-4-(3-tetrahydropyrolylpropoxyl)] pent-4-enoic acid, and tetrapyrolyl propoxyl methoxyl phenyl prop-2-enoic acid for PB-3, 3-oxo-5-[4-hydroxyl-5-methoxyl-3-(1-morpholinylmethyl)] pent-4-enoic aldehyde, 3-oxo-5-(4-hydroxyl-5-methoxyl-3-(1-morpholinylmethyl)) pent-4-enoic acid and 2-hydroxyl-3-methoxyl-5-(7-(3-methoxyl-4-hydroxylphenyl)-3,5-dioxo-4,4-dimethyl hept-1,6-dienyl) benzoic acid for DY-1, respectively. The degradation pathways of curcumin and its derivatives were presented in addition

Experimental Construction of Optical Multi-qubit Cluster States From Bell States

Cluster states serve as the central physical resource for the measurement-based quantum computation. We here present a simple experimental demonstration of the scalable cluster-state-construction scheme proposed by Browne and Rudolph. In our experiment, three-photon cluster states are created from two Bell states using linear optical devices. By observing a violation of three-particle Mermin inequality of $|| = 3.10\pm0.03$, we also for the first time report a genuine three-photon entanglement. In addition, the entanglement properties of the cluster states are examined under $\sigma_z$ and $\sigma_x$ measurements on a qubit.Comment: 4 pages, 4 figures, submitte