We propose a highly-sensitive temperature sensor employing a Mach-Zehnder interferometer (MZI) based on silicon-on-insulator (SOI) platform. The waveguide widths in the two MZI arms are tailored to ...have different temperature sensitivities but nearly the same group refractive indices. A temperature sensor with an enhanced sensitivity of larger than 438pm/°C is experimentally demonstrated, which is over seven times larger than that of conventional silicon optical temperature sensor (about 60pm/°C for quasi-TM mode). Moreover, the sensor is easy to fabricate, only by a single mask, and no need of any polymer cladding, which makes it more robust, and can be used in lab-on-chip systems as a temperature monitor.
•This study examines the compressive and flexural behaviour of a new material mixture, RSRAC.•RSRAC with an optimal rubber content displays good compressive behaviour.•RSRAC is a more environmentally ...friendly alternative to normal rubber concrete for use in the flexural member.
Using recycled concrete and crumb rubber as aggregates to produce green concrete is a promising technology toward sustainability in the construction industry. In this study, the compressive and flexural behaviours of a new type of concrete material, rubber crumb and steel-fibre-reinforced recycled aggregate concrete (RSRAC), are investigated. To popularise the application of this new type of green building material, an experimental study was conducted to investigate the effect of the rubber content on the compressive and flexural behaviours of RSRAC. A total of 18 cubes (150mm) and 18 cylinders (150mm×200mm) were tested under axial compressive loading, and 18 prisms of 150×150×550mm were tested subjected to three-point bending. The crumb rubber content was varied in the investigation at levels of 0%, 4%, 8%, 12% and 16% by volume substitution of sand. Recycled concrete aggregate (RCA) was introduced into the concrete mixture by 100% volume substitution of natural coarse aggregate (NCA), and 1% volumetric quantity of steel fibre was added to the concrete mixture. The effect of the rubber content on the compressive and flexural strength, failure mode, modulus of elasticity and toughness of RSRAC was analysed. The results indicate that RSRAC with an optimal rubber content displays good compressive behaviour compared with normal NCA concrete. RSRAC is also a more environmentally friendly alternative to normal rubber concrete for use in theflexural members of concrete structures.
Heterochromatin is a tightly packed form of chromatin that is associated with DNA methylation and histone 3 lysine 9 methylation (H3K9me). Here, we identify an H3K9me2-binding protein, Agenet domain ...(AGD)-containing p1 (AGDP1), in Arabidopsis thaliana. Here we find that AGDP1 can specifically recognize the H3K9me2 mark by its three pairs of tandem AGDs. We determine the crystal structure of the Agenet domain 1 and 2 cassette (AGD12) of Raphanus sativus AGDP1 in complex with an H3K9me2 peptide. In the complex, the histone peptide adopts a unique helical conformation. AGD12 specifically recognizes the H3K4me0 and H3K9me2 marks by hydrogen bonding and hydrophobic interactions. In addition, we find that AGDP1 is required for transcriptional silencing, non-CG DNA methylation, and H3K9 dimethylation at some loci. ChIP-seq data show that AGDP1 preferentially occupies long transposons and is associated with heterochromatin marks. Our findings suggest that, as a heterochromatin-binding protein, AGDP1 links H3K9me2 to DNA methylation in heterochromatin regions.
We investigate the detectability of gravitational waves that have been lensed by a spinless stellar-mass black hole, with respect to the advanced LIGO. By solving the full relativistic linear wave ...equations in the spacetime of a Schwarzschild black hole, we find that the strong gravity can create unique signals in the lensed waveform, particularly during the merger and ring-down stages. The differences in terms of fitting factor between the lensed waveform and best-fitted unlensed general relativity template with spin precession and higher-order multipoles are greater than 5% for the lens black hole mass within 70M_{⊙}<M_{lens}<133.33M_{⊙} under advanced LIGO's sensitivity. This is up to 5 times more detectable than the previous analysis based on the weak field approximation for a point mass and covers most part of the black hole mass gap predicted by stellar evolution theory. Based on Bayesian inference, the lensing feature can be distinguished with a signal-to-noise ratio of 12.5 for M_{lens}=70M_{⊙} and 19.2 for M_{lens}=250M_{⊙}, which is attainable for advanced LIGO.
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The diterpene synthase AlTS was identified from Aspergillus luchuensis. AlTS catalyses the formation of the diterpene hydrocarbon spiroluchuene A, which exhibits a novel skeleton characterised by a ...spirocyclic ring system. The cyclisation mechanism towards this compound was elucidated through isotopic labelling experiments in conjunction with DFT calculations and metadynamic simulations. The biosynthetic intermediate luchudiene, besides the derivative spiroluchuene B, was captured from an enzyme variant obtained through site‐directed mutagenesis. With its 10‐membered ring luchudiene is structurally related to germacrenes and can undergo a Cope rearrangement to luchuelemene.
A diterpene synthase for spiroluchuene A exhibiting a novel skeleton was discovered from Aspergillus luchuensis. Enzyme engineering through site‐directed mutagenesis allowed for the isolation of spiroluchuene B and the intermediate spiroluchuene. The enzyme mechanism was deeply studied through isotopic labelling experiments, DFT calculations and metadynamic simulations. The thermal reactions of luchudiene were studied.
We present a widely tunable 25 Gbps transmitter that integrates a V-Cavity Laser and an electro-absorption modulator using an identical epitaxial layer scheme. The transmitter exhibits a wavelength ...tuning of 41 channels with 100 GHz spacing and a side-mode suppression ratio above 42 dB by varying the TEC temperature by 32 °C. All channels show clear eye diagram openings at a rate of 25 Gbps with a dynamic extinction ratio higher than 9 dB at a fixed peak-to-peak driving voltage of 2 V. Bit-error-rate measurements demonstrate a power penalty less than 3 dB for transmission through 10 km of standard single-mode fiber. This tunable transmitter offers a cost-effective solution that is suitable for use in DWDM access networks.
ObjectivesOesophageal squamous cell carcinoma (OSCC) and adenocarcinoma (OAC) are distinct cancers in terms of a number of clinical and epidemiological characteristics, complicating the design of ...clinical trials and biomarker developments. We analysed 1048 oesophageal tumour-germline pairs from both subtypes, to characterise their genomic features, and biological and clinical significance.DesignPreviously exome-sequenced samples were re-analysed to identify significantly mutated genes (SMGs) and mutational signatures. The biological functions of novel SMGs were investigated using cell line and xenograft models. We further performed whole-genome bisulfite sequencing and chromatin immunoprecipitation (ChIP)-seq to characterise epigenetic alterations.ResultsOSCC and OAC displayed nearly mutually exclusive sets of driver genes, indicating that they follow independent developmental paths. The combined sample size allowed the statistical identification of a number of novel subtype-specific SMGs, mutational signatures and prognostic biomarkers. Particularly, we identified a novel mutational signature similar to Catalogue Of Somatic Mutations In Cancer (COSMIC)signature 16, which has prognostic value in OSCC. Two newly discovered SMGs, CUL3 and ZFP36L2, were validated as important tumour-suppressors specific to the OSCC subtype. We further identified their additional loss-of-function mechanisms. CUL3 was homozygously deleted specifically in OSCC and other squamous cell cancers (SCCs). Notably, ZFP36L2 is associated with super-enhancer in healthy oesophageal mucosa; DNA hypermethylation in its super-enhancer reduced active histone markers in squamous cancer cells, suggesting an epigenetic inactivation of a super-enhancer-associated SCC suppressor.ConclusionsThese data comprehensively contrast differences between OSCC and OAC at both genomic and epigenomic levels, and reveal novel molecular features for further delineating the pathophysiological mechanisms and treatment strategies for these cancers.
Background
Accumulating evidence suggested that the use of metformin had more benefits for both prevention and treatment of tuberculosis (TB) than non-metformin use in patients with diabetes mellitus ...(DM); however, it remains to be fully elucidated on this topic. Thus, we conducted a systematic review and meta-analysis of published studies to determine the association between metformin use and TB in patients with diabetes.
Methods
The MEDLINE, EMBASE, Information Sciences Institute (ISI) Web of Science, and Cochrane CENTRAL databases were searched from their inception to 15 April 2019. Studies that evaluated the use of metformin and TB disease were included. The quality of each study was evaluated through the Newcastle-Ottawa Scale (NOS). For pooled data, the relative risk (RR) and 95% confidence intervals (CIs) were calculated; otherwise, a systematic review.
Results
Seventeen observational studies were included, all of which indicated a low risk of bias according to the NOS. The pooled analysis showed that metformin use was associated with a significantly lower active TB incidence and mortality among individuals with DM (RR = 0.51; 95% CI, 0.38–0.69,
P
⩽ 0.001) and with TB-DM (RR = 0.34; 95% CI, 0.20–0.57,
P
⩽ 0.001), respectively.
Conclusions
This meta-analysis indicated metformin use is related to benefits in both prevention and treatment outcomes of tuberculosis among patients with diabetes. Prospective clinical trials are needed to confirm these associations.
Abstract The TeV afterglow of the BOAT GRB 221009A was interpreted as arising from a narrow jet, while the radio-to-X-ray afterglows were interpreted as arising from a wide structured jet. However, ...there is no model explaining the TeV and lower-energy multiwavelength afterglows simultaneously. We here investigate a two-component jet model, including a narrow uniform core with a wide structured wing, to explain both the multiwavelength afterglows that last up to 100 days. We find that to explain the early TeV afterglow with the inverse-Compton process, we need a circumburst density higher than ≳0.1 cm −3 , while the radio afterglow and the H.E.S.S. upper limit combine to constrain the density to be lower at larger radii. Thus, a decreasing density profile with radius is favored. Considering that the rising TeV light curve during the afterglow onset favors a constant-density medium, we invoke a stratified density profile, including a constant-density profile at small radii and a wind density profile at large radii. We find that the two-component jet model with such a stratified density profile can explain the TeV, X-ray, and optical afterglows of GRB 221009A, although the radio fluxes exceed the observed ones by a factor of 2 at later epochs. The discrepancy in the radio afterglow could be resolved by invoking some nonstandard assumption about the microphysics of afterglow shocks. The total kinetic energy of the two components in our model is ≲10 52 erg, significantly smaller than that in the single structured jet models.
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