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A variety of new hybrid derivatives of isoflavone-1,2,3-triazole conjugated heterocycles has been synthesized from 7-hydroxy isoflavone by Cu(I) catalysed azidoalkyne [3+2]cycloaddition. The synthesized compounds have been tested for anti-bacterial activity against gram positive Bacillus subtilis, gram negative Escherichia coli and anti-fungal activity against Sclerotium Rolfsii, Macrophomina phaseolina. Three products demonstrate moderate activity against Bacillus subtilis and three compounds are characterized as highly anti-fungal agents for Sclerotium Rolfsii. [ABSTRACT FROM AUTHOR]

Mountain hares Lepus timidus L. typify species that occupy a broad geographic range and have flexible foraging and nutritional strategies. Such species may show a range of responses to habitat modification. This study aimed to provide a basis for prediction of the impact of mountain hares on woodland establishment, and of woodland establishment on mountain hare distribution. The selection of and the extent of incorporation of new woodland into the home range of mountain hares was investigated in an area where Scots pine Pinus sylvestris L. woodland was establishing within their usual habitat in Britain, upland heather moorland. Seasonal home, day and night-range sizes of radio-tracked mountain hares were determined using the multinuclear probability polygon technique and analysed using residual maximum likelihood (REML). Habitat selection was analysed using compositional analysis. Three main habitat types were available to hares: heather moorland with trees, heather moorland and grassland-mire. Mean home-range size of mountain hares in summer was 10.3 ha and in winter 9.6 ha. There were no significant seasonal or sex differences in home-range size. Females selected grassland-mire habitat in summer and showed no strong selection for any habitat in winter. Males selected heather moorland in both summer and winter. Heather moorland with trees was not selected preferentially by mountain hares of either sex in summer or winter. The absence of selection for areas of newly establishing-Scots pine woodland suggests that any browsing damage to trees by hares is most likely to be a function of the local abundance of mountain hares, rather than a result of active preference of hares for the modified habitat. [ABSTRACT FROM AUTHOR]

A new series of 1,4-disubstituted 1,2,3-triazole derivatives tethered to a 2H-chromene scaffold have been synthesized via a click reaction. The synthesized chromene–triazole conjugates were screened for their antibacterial activity against E. coli, S. aureus, P. aeruginosa and B. subtilis, as well as for antifungal activity against A. niger and C. albicans. Among the 17 synthesized compounds, 6 derivatives showed the best antimicrobial activity. Molecular docking studies of the title compounds with carotenoid dehydrosqualene synthase (PDB: 2ZCS) revealed docking scores within the range 98.241–91.488 against 106.573 for the reference ligand Ciprofloxacin and with lanosterol 14α-demethylase (CYP51; PDB ID: 5V5Z), 103.672–96.917 against 110.839 for the reference ligand Voriconazole. [ABSTRACT FROM AUTHOR]

Objective: In this paper a wide-band integrated current driver for electrical impedance tomography (EIT) is presented. The application is primarily for prostate and breast cancer detection which require the tissue to be interrogated at frequencies up to 10 MHz while achieving low harmonic distortion and high accuracy. Approach: The current driver is based on current conveyor architecture and can deliver 1.2 mA of peak to peak ac current between frequencies of 100 Hz–10 MHz. It is fabricated in CMOS 0.18 m technology with a power supply of 3.3 V, and occupies a core area of 0.26 . Main results: The measured harmonic distortion for a peak current of 1.2 mA is  < for frequencies less than 100 kHz, and increases to at 10 MHz. The measured output impedance of the current driver is 101 k at 1 MHz and 19.5 k at 10 MHz. Significance: The circuit is suitable for high frequency active electrode applications. [ABSTRACT FROM AUTHOR]

Carbon concentrating mechanism (CCM) and photorespiration (PR) are interlinked and co-regulated in Chlamydomonas reinhardtii, but conditions where co-regulation alters are not sufficiently explored. Here, we uncover that PR gene transcripts, like CCM transcripts, are induced even in the dark when both processes are not active. Such diurnal cycles show that transcript levels peak in the middle of 12 h day, decline by early part of 12-h dark followed by their onset again at mid-dark. Interestingly, the onset in the mid-dark phase is sensitive to high CO2, implying that the active carbon sensing mechanism operates even in the dark. The rhythmic alterations of both CCM and PR transcript levels are unlinked to circadian clock: the "free-running state" reveals no discernible rhythmicity in transcript changes. Only continuous light leads to high transcript levels but no detectable transcripts were observed in continuous dark. Asynchronous continuous light cultures, upon shifting to low from high CO2 exhibit only transient induction of PR transcripts/proteins while CCM transcript induction is stable, indicating the loss of co-regulation between PR and CCM gene transcription. Lastly, we also describe that both CCM and PR transcripts/proteins are induced in low CO2 even in mixotrophic cultures, but only in high light, the same being attenuated in high CO2, implying that high light is a mandatory "trigger" for CCM and PR induction in low CO2 mixotrophy. Our study provides comprehensive analyses of conditions where CCM and PR were differently regulated, setting a paradigm for a detailed mechanistic probing of these responses. [ABSTRACT FROM AUTHOR]

We demonstrate a tunable multiwavelength fiber laser in this paper. The multiwavelength comb is produced by a self-seeded Brillouin-erbium fiber laser (BEFL). The self-seeded Brilllouin pump is achieved by incorporation of a transmissive Sagnac loop filter and 2 km single mode fiber. We study the influence of the transmissive Sagnac loop filter on the BEFL in detail, include the tunable characteristics of the BEFL, and the influence of the Sagnac loop bandwidth on the multiwavelength band. A multiwavelength band with 52 lines is achieved when the bandwidth of the Sagnac loop filter is 83.3 nm. At the same time, we observed dual Brillouin bands exciting. [ABSTRACT FROM AUTHOR]

The study of structure and dynamics of bound DNA has special implications in the context of its biological as well as material functions. It is of fundamental importance to understand how a binding surface affects different positions of DNA with respect to its open ends. Because double-stranded (ds) and single-stranded (ss) DNA are the predominant functional forms, we studied the site-specific dynamics of these DNA forms, bound to the oppositely charged surface of histones, and compared the effects with that of DNA bound to cetyltrimethyl ammonium bromide micelles. We utilized a time-resolved fluorescence technique using fluorescent base analogue 2-aminopurine located at specific positions of synthetic poly-A DNA strands to obtain fluorescence lifetime and anisotropy information. It is observed that the binding leads to overall rigidification of the DNA backbone, and the highly flexible ends show drastic dampening of their internal dynamics as well as the fraying motions. In the case of ds-DNA, we find that the binding not only decreases the flexibility but also leads to significant weakening of base-stacking interactions. An important revelation that strong binding between DNA and the binding agents (histones as well as micelles) does not dampen the internal dynamics of the bases completely suggests that the DNA in its bound form stays in some semiactive state, retaining its full biological activity. Considering that the two binding agents (histones and micelles) are chemically very different, an interesting comparison is made between DNA−histones and DNA−micelle interactions. [ABSTRACT FROM AUTHOR]

Aggressive angiomyxoma is a rare, locally invasive mesenchymal tumor, occurring predominantly in the pelvic-perineal region of adults and carries a high risk for local relapse and hence the need to differentiate it from the other mesenchymal tumors occurring in this region. Presentation as a pedunculated polyp, like in our case, is unusual for this rare tumor. Except for positive surgical margins, there are no clinical or histological means for predicting the tumor recurrence. A diligent long-term follow-up is mandatory. Though rare, this tumor needs to be considered in the differential diagnosis of vulval polyps. [ABSTRACT FROM AUTHOR]

Since the last Fusion Energy Conference, the HL-2A experiment has made significant progress in the following areas: (i) physics on low-intermediate-high (L-I-H) transition and pedestal dynamics; (ii) magnetohydrodynamic (MHD) and energetic-particle (EP) physics; (iii) interaction between neoclassical tearing modes (NTMs) and non-local transport; (iv) and edge localized mode (ELM) mitigation by supersonic molecular beam injection (SMBI). Two types of limit-cycle-oscillations (LCOs) were observed in the intermediate phase (I-phase), which indicated a second type of predator-prey process between turbulence and pressure gradient in addition to the conventional predator–prey involving zonal flows and turbulence. It was found that a kink-type MHD mode often crashed prior to the I-H transition, which played a crucial role in triggering H-mode by increasing the edge pressure gradient and E  ×  B flow shear and consequently suppressing turbulent transport. It was also found that impurity concentration played an important role in the multi-transitions between ELM-free H-mode and I-phase. Besides, a quasi-coherent mode around 50–100 kHz was found to be associated with pedestal density gradient saturation in ELM-free H-mode. For the first time, two types of magnetic activities with n  =  0 were observed in the presence of strong tearing modes. Fourier bicoherence analysis suggested that these modes were generated by the nonlinear coupling between Alfvén eigenmodes (AEs) and low-frequency MHD modes. Up- and down-sweeping reverse shear Alfvén eigenmodes (RSAEs) were identified experimentally. The transitions between fishbone and long-lived mode (LLM) were also investigated. The results showed that fishbone could transit from/to LLM and even trigger tearing modes (TMs). For non-local transport, key characteristics of enhanced avalanches in the theory of self-organized criticality (SOC) were identified, including high Hurst exponents and large-scale radial propagation. Experimental results revealed a close correlation between NTMs and non-local transport. In addition, studies on ELM mitigation by SMBI have also progressed substantially. [ABSTRACT FROM AUTHOR]