Maxwell's two-demon engine under pure dephasing noise

The interplay between thermal machines and quantum correlations is of great interest in both quantum thermodynamics and quantum information science. Recently, a quantum Szil\'ard engine has been proposed, showing that the quantum steerability between a Maxwell's demon and a work medium can be beneficial to a work extraction task. Nevertheless, this type of quantum-fueled machine is usually fragile in the presence of decoherence effects. We provide an example of the pure dephasing process, showing that the engine's quantumness can be degraded. Therefore, in this work, we tackle this question by introducing a second demon who can access a control system and make the work medium pass through two dephasing channels in a manner of quantum superposition. Furthermore, we provide a quantum circuit to simulate our proposed concept and test it on IBMQ and IonQ quantum computers.Comment: 10 pages, 7 figures, 2 table

Exploring the Mechanism Responsible for Cellulase Thermostability by Structure-Guided Recombination

Cellulases from Bacillus and Geobacillus bacteria are potentially useful in the biofuel and animal feed industries. One of the unique characteristics of these enzymes is that they are usually quite thermostable. We previously identified a cellulase, GsCelA, from thermophilic Geobacillus sp. 70PC53, which is much more thermostable than its Bacillus homolog, BsCel5A. Thus, these two cellulases provide a pair of structures ideal for investigating the mechanism regarding how these cellulases can retain activity at high temperature. In the present study, we applied the SCHEMA non-contiguous recombination algorithm as a novel tool, which assigns protein sequences into blocks for domain swapping in a way that lessens structural disruption, to generate a set of chimeric proteins derived from the recombination of GsCelA and BsCel5A. Analyzing the activity and thermostability of this designed library set, which requires only a limited number of chimeras by SCHEMA calculations, revealed that one of the blocks may contribute to the higher thermostability of GsCelA. When tested against swollen Avicel, the highly thermostable chimeric cellulase C10 containing this block showed significantly higher activity (22%-43%) and higher thermostability compared to the parental enzymes. With further structural determinations and mutagenesis analyses, a 3_(10) helix was identified as being responsible for the improved thermostability of this block. Furthermore, in the presence of ionic calcium and crown ether (CR), the chimeric C10 was found to retain 40% residual activity even after heat treatment at 90°C. Combining crystal structure determinations and structure-guided SCHEMA recombination, we have determined the mechanism responsible for the high thermostability of GsCelA, and generated a novel recombinant enzyme with significantly higher activity

Women with endometriosis have higher comorbidities: Analysis of domestic data in Taiwan

AbstractEndometriosis, defined by the presence of viable extrauterine endometrial glands and stroma, can grow or bleed cyclically, and possesses characteristics including a destructive, invasive, and metastatic nature. Since endometriosis may result in pelvic inflammation, adhesion, chronic pain, and infertility, and can progress to biologically malignant tumors, it is a long-term major health issue in women of reproductive age. In this review, we analyze the Taiwan domestic research addressing associations between endometriosis and other diseases. Concerning malignant tumors, we identified four studies on the links between endometriosis and ovarian cancer, one on breast cancer, two on endometrial cancer, one on colorectal cancer, and one on other malignancies, as well as one on associations between endometriosis and irritable bowel syndrome, one on links with migraine headache, three on links with pelvic inflammatory diseases, four on links with infertility, four on links with obesity, four on links with chronic liver disease, four on links with rheumatoid arthritis, four on links with chronic renal disease, five on links with diabetes mellitus, and five on links with cardiovascular diseases (hypertension, hyperlipidemia, etc.). The data available to date support that women with endometriosis might be at risk of some chronic illnesses and certain malignancies, although we consider the evidence for some comorbidities to be of low quality, for example, the association between colon cancer and adenomyosis/endometriosis. We still believe that the risk of comorbidity might be higher in women with endometriosis than that we supposed before. More research is needed to determine whether women with endometriosis are really at risk of these comorbidities

Crystal Structure and Potential Head-to-Middle Condensation Function of a <i>Z</i>,<i>Z</i>‑Farnesyl Diphosphate Synthase

Plants produce a wide variety of secondary metabolites in response to adverse environmental factors. <i>Z</i>,<i>Z</i>-Farnesyl diphosphate (<i>Z</i>,<i>Z</i>-FPP), synthesized by <i>Z</i>,<i>Z</i>-farnesyl diphosphate synthase (<i>z</i>FPS), supports the formation of phytochemicals in wild tomatoes. Here, the crystal structure of N-terminal truncated <i>z</i>FPS (Δ<i>z</i>FPS) was determined. Irregular products including lavandulyl diphosphate and an unknown compound were surprisingly found. Apart from the truncated N-terminus as a functional regulator, structure-based analysis and mutagenesis assays revealed a residue H103 in Δ<i>z</i>FPS as one of the key elements to this irregular function. A series of substrate–enzyme complex structures were obtained from Δ<i>z</i>FPS-H103Y by co-crystallizing with isopentenyl diphosphate, dimethylallyl thiolodiphosphate, or both. Various substrate-binding modes were revealed. The catalytic mechanisms of both the head-to-tail and head-to-middle reactions in Δ<i>z</i>FPS were proposed. Functional switch between the two mechanisms in this enzyme and the essential role played by the flexible C-terminus were elucidated as well

Establishment of an Immunocompetent Metastasis Rat Model with Hepatocyte Cancer Stem Cells

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer mortality. Cancer stem cells (CSCs) are responsible for the maintenance, metastasis, and relapse of various tumors. The effects of CSCs on the tumorigenesis of HCC are still not fully understood, however. We have recently established two new rat HCC cell lines HTC and TW-1, which we isolated from diethylnitrosamine-induced rat liver cancer. Results showed that TW-1 expressed the genetic markers of CSCs, including CD133, GSTP1, CD44, CD90, and EpCAM. Moreover, TW-1 showed higher tolerance to sorafenib than HTC did. In addition, tumorigenesis and metastasis were observed in nude mice and wild-type rats with TW-1 xenografts. Finally, we combined highly expressed genes in TW-1/HTC with well-known biomarkers from recent HCC studies to predict HCC-related biomarkers and able to identify HCC with AUCs &gt; 0.9 after machine learning. These results indicated that TW-1 was a novel rat CSC line, and the mice or rat models we established with TW-1 has great potential on HCC studies in the future

The thermostability of C10 is enhanced by addition of Ca²⁺ and CR.

<p>Thermotolerance of the C10 chimera and parental enzymes in the absence of Ca²⁺ (A), presence of Ca²⁺ (B), presence of CR (C), and presence of both Ca²⁺ and CR (D). Purified cellulases (1μg) were pre-incubated in 50 mM sodium acetate buffer (pH 5.0) at different temperatures for 10 min with or without additional Ca²⁺ 0.05 mM or/and CR 6.25×10⁻³ mM. The residual enzyme activity was then determined on 1% PASC at pH 5.0 at their optimal temperature for 6 hrs. The 100% value of relative activity refers to the optimal activity of each enzyme without thermal treatment.</p

Informative subsets of parental, chimeric, and designed GH5 cellulases.

<p>Informative subsets of parental, chimeric, and designed GH5 cellulases.</p

Characterization of GH5 chimeras.

<p>(A) Activity profiles of GH5 parents and chimeras at high temperatures. (B) Residual activities (thermostability) of GH5 parents and chimeras after heat-treatment. One microgram of purified cellulases was pre-incubated in 50 mM sodium acetate buffer (pH 5.0) at different temperatures for 10 min. The residual enzyme activities were then determined on 1% PASC at pH 5.0 at their optimal temperature for 6 hrs. Relative activities were compared with the optimal activity of each enzyme without a pre-incubating treatment at 60°C. Some of the enzymes, e.g. C5, do not have the initial point (60°C) of 100% because their optimal activities are not at this reaction temperature and therefore have a slightly lower staring points in the analyses with 60°C pre-incubation temperature. (C) Acid stability of the parents and chosen chimeras. One microgram of purified cellulases was pre-incubated in 50 mM buffer with variable pH for 12 hrs. The residual enzyme activity was determined. Relative activities were compared with the optimal activity of each enzyme without a pre-incubating treatment at pH 5. (D) Long-term activity of the most stable chimera C10 compared with its parents in PASC hydrolysis. One microgram of purified cellulases plus 0.5 μg Novo-188 (β-glucosidase, Novozyme) was added into 1% PASC at 50°C, pH 5.0 for 6, 12, 24, 36, 48, and 60 hrs.</p