1,770 research outputs found

    The bldC developmental locus of Streptomyces coelicolor encodes a member of a family of small DNA-binding proteins related to the DNA-binding domains of the MerR family.

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    The bldC locus, required for formation of aerial hyphae in Streptomyces coelicolor, was localized by map-based cloning to the overlap between cosmids D17 and D25 of a minimal ordered library. Subcloning and sequencing showed that bldC encodes a member of a previously unrecognized family of small (58- to 78-residue) DNA-binding proteins, related to the DNA-binding domains of the MerR family of transcriptional activators. BldC family members are found in a wide range of gram-positive and gram-negative bacteria. Constructed {Delta}bldC mutants were defective in differentiation and antibiotic production. They failed to form an aerial mycelium on minimal medium and showed severe delays in aerial mycelium formation on rich medium. In addition, they failed to produce the polyketide antibiotic actinorhodin, and bldC was shown to be required for normal and sustained transcription of the pathway-specific activator gene actII-orf4. Although {Delta}bldC mutants produced the tripyrrole antibiotic undecylprodigiosin, transcripts of the pathway-specific activator gene (redD) were reduced to almost undetectable levels after 48 h in the bldC mutant, in contrast to the bldC+ parent strain in which redD transcription continued during aerial mycelium formation and sporulation. This suggests that bldC may be required for maintenance of redD transcription during differentiation. bldC is expressed from a single promoter. S1 nuclease protection assays and immunoblotting showed that bldC is constitutively expressed and that transcription of bldC does not depend on any of the other known bld genes. The bldC18 mutation that originally defined the locus causes a Y49C substitution that results in instability of the protein

    The Americanization of Japanese Law

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    A regional atmosphere-ocean climate system model (CCLMv5.0clm7-NEMOv3.3-NEMOv3.6) over Europe including three marginal seas: On its stability and performance

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    The frequency of extreme events has changed, having a direct impact on human lives. Regional climate models help us to predict these regional climate changes. This work presents an atmosphere–ocean coupled regional climate system model (RCSM; with the atmospheric component COSMO-CLM and the ocean component NEMO) over the European domain, including three marginal seas: the Mediterranean, North, and Baltic Sea. To test the model, we evaluate a simulation of more than 100 years (1900–2009) with a spatial grid resolution of about 25 km. The simulation was nested into a coupled global simulation with the model MPI-ESM in a low-resolution configuration, whose ocean temperature and salinity were nudged to the ocean–ice component of the MPI-ESM forced with the NOAA 20th Century Reanalysis (20CR). The evaluation shows the robustness of the RCSM and discusses the added value by the coupled marginal seas over an atmosphere-only simulation. The coupled system is stable for the complete 20th century and provides a better representation of extreme temperatures compared to the atmosphere-only model. The produced long-term dataset will help us to better understand the processes leading to meteorological and climate extremes

    Автоматическое закорачивание отдельных фаз линий для ликвидации дуговых коротких замыканий

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    During the last few years high power diode laser arrays have become well established for direct material processing due to their high efficiency of more than 50%. But standard broad-area waveguide designs are susceptible to modal instabilities and filamentations resulting in low beam qualities. The beam quality increases by more than a factor of four by using tapered laser arrays, but so far they suffer from lower efficiencies. Therefore tapered lasers are mainly used today as single emitters in external resonator configurations. With increased output power and lifetime, they will be much more attractive for material processing and for pumping of fiber amplifiers. High efficiency tapered mini bars emitting at a wavelength of 980 nm are developed, and in order to qualify the bars, the characteristics of single emitters and mini bars from the same wafer have been compared. The mini bars have a width of 6 mm with 12 emitters. The ridge waveguide tapered lasers consist of a 500 µm long ridge and a 2000 µm long tapered section. The results show very similar behavior of the electro-optical characteristics and the beam quality for single emitters and bars. Due to different junction temperatures, different slope efficiencies were measured: 0.8 W/A for passively cooled mini bars and 1.0 W/A for actively cooled mini-bars and single emitters. The threshold current of 0.7 A per emitter is the same for single emitters and emitter arrays. Output powers of more than 50 W in continuous wave mode for a mini bar with standard packaging demonstrates the increased power of tapered laser bars

    Nipple Sparing Mastectomy Techniques: A Literature Review and an Inframammary Technique

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    Nipple sparing mastectomy (NSM) has quickly become an accepted technique for patients with selected cancers and for risk reducing surgery. Much of its surgical acceptance over the last decade has been based on the low risk of nipple areolar complex (NAC) occurrence in breast cancer patients. Improved patient satisfaction due to improved cosmetic outcomes with reconstruction have also driven its popularity. We reviewed current English journals to determine the NSM techniques which achieve the lowest complications, best outcomes, and best patient satisfaction. We researched studies showing reductions in complications with improved surgical techniques and patient selection which have been implicated in improved results. In the studies reviewed, incision placement, away from the nipple, resulted in the lowest rates of ischemic nipple complications and the best cosmetic outcomes. The effect of other factors such as surgeon experience and thickness of skin flap development were more difficult to prove. Leaving a 2-3 mm rim of tissue around the nipple bundle was shown to help preserve the nipple vascularity. Lower complication rates with improved outcomes and patient satisfaction were reported in the literature in patients with B or smaller cup sizes, non-smokers, and patients with lower body mass index (BMI). Incision placement, away from the nipple, with preservation of a 2-3 mm rim of tissue around the nipple bundle along with careful patient selection were the most significant variables reviewed which helped to lower complications rates of NSM. Coordinated surgical planning with the breast and plastic surgeons to determine the best surgical approach for each individual patient is necessary to obtain the best results. Although short-term oncologic follow-up seems to be acceptable, longer follow-up will still be needed to define the best breast cancer surgical candidates for the nipple sparing approach

    Community based responses to the Japanese Tsunami: a bottom up approach

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    The 2011 Tohuku earthquake and tsunami are said to be the most powerful ever to hit Japan. The result was tremendous loss of life, homes and livelihoods; the destruction of infrastructures; and the disruption of basic facilities. The aftermath of this disaster is the context of our research and we aim to show how a CBOR intervention approach can complement and be integrated into a larger social science project to offer a more praxis grounded understanding of the challenges faced. Our focus is on the interventions employed at the community level to reconstruct and rebuild a marginalized and devastated community-Minami Sanriku. We employ an arts-based methodology, supported by traditional qualitative methods, both as a means of data gathering and as a CBOR intervention in its own right, in order to understand and contribute to the socio-cultural dynamics of resilience and resilience building. Our pluralist and participatory methodology places community and concerned citizens at the heart of the rebuilding process. We analyze how a community in crisis draws upon social networks, cultural practices and collective interventions to rebuild from within. We frame our findings in terms of culture, community and resilience, and examine three interventions which have the ultimate aim of 'building back better'

    A novel compartment, the 'subqpical stem' of the aerial hyphae, is the location of a sigN-dependent, developmentally distinct transcription in Streptomyces coelicolor.

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    Streptomyces coelicolor has nine SigB-like RNA polymerase sigma factors, several of them implicated in morphological differentiation and/or responses to different stresses. One of the nine, SigN, is the focus of this article. A constructed sigN null mutant was delayed in development and exhibited a bald phenotype when grown on minimal medium containing glucose as carbon source. One of two distinct sigN promoters, sigNP1, was active only during growth on solid medium, when its activation coincided with aerial hyphae formation. Transcription from sigNP1 was readily detected in several whi mutants (interrupted in morphogenesis of aerial mycelium into spores), but was absent from all bld mutants tested, suggesting that sigNP1 activity was restricted to the aerial hyphae. It also depended on sigN, thus sigN was autoregulated. Mutational and transcription studies revealed no functional significance to the location of sigN next to sigF, encoding another SigB-like sigma factor. We identified another potential SigN target, nepA, encoding a putative small secreted protein. Transcription of nepA originated from a single, aerial hyphae-specific and sigN-dependent promoter. While in vitro run-off transcription using purified SigN on the Bacillus subtilis ctc promoter confirmed that SigN is an RNA polymerase sigma factor, SigN failed to initiate transcription from sigNP1 and from the nepA promoter in vitro. Additional in vivo data indicated that further nepA upstream sequences, which are likely to bind a potential activator, are required for successful transcription. Using a nepA–egfp transcriptional fusion we located nepA transcription to a novel compartment, the ‘subapical stem’ of the aerial hyphae. We suggest that this newly recognized compartment defines an interface between the aerial and vegetative parts of the Streptomyces colony and might also be involved in communication between these two compartments
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