177 resultados para 174-1073


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Single particle analysis (SPA) coupled with high-resolution electron cryo-microscopy is emerging as a powerful technique for the structure determination of membrane protein complexes and soluble macromolecular assemblies. Current estimates suggest that ∼104–105 particle projections are required to attain a 3 Å resolution 3D reconstruction (symmetry dependent). Selecting this number of molecular projections differing in size, shape and symmetry is a rate-limiting step for the automation of 3D image reconstruction. Here, we present SwarmPS, a feature rich GUI based software package to manage large scale, semi-automated particle picking projects. The software provides cross-correlation and edge-detection algorithms. Algorithm-specific parameters are transparently and automatically determined through user interaction with the image, rather than by trial and error. Other features include multiple image handling (∼102), local and global particle selection options, interactive image freezing, automatic particle centering, and full manual override to correct false positives and negatives. SwarmPS is user friendly, flexible, extensible, fast, and capable of exporting boxed out projection images, or particle coordinates, compatible with downstream image processing suites.

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We report the photoinduced conjugation of polymers synthesized via reversible addition−fragmentation chain transfer (RAFT) polymerization with a number of low molecular weight (functional) olefins. Upon irradiation of a solution of an aliphatic alkene and the benzyl dithioacetic acid ester (CPDA) or dodecyl trithiocarbonate (DoPAT) functional poly(alkyl acrylate) at the absorption wavelength of the thiocarbonyl group (315 nm), incorporation of the alkene at the polymer chain-end occurred. The most efficient systems identified with regard to the rate of reaction and yield were poly(butyl acrylate)/CPDA/ethyl vinyl ether (78% monoinsertion product after 1 h) and poly(butyl acrylate)/CPDA/1-pentene (73% insertion product after 7 h) at ambient temperature. An in-depth analysis of the reaction mechanism by 1H NMR and online size-exclusion chromatography-electrospray ionization tandem mass spectrometry (SEC/ESI−MSn) revealed that a possible [2 + 2] photoaddition mechanism of conjugation does not take place. Instead, fast β-cleavage of the photoexcited RAFT-end group with subsequent radical addition of an alkene was observed for all employed systems. The presented reaction thus provides a means of spatial and temporal control for the conjugation of alkenes to thiocarbonyl thio-capped macromolecules via the use of UV radiation.

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Little is known about the influence that patients themselves have on their loyalty to a general practitioner (GP). Consequently, a theoretical framework that draws on diverse literature is proposed to suggest that along with satisfaction, patient loyalty is an important outcome for GPs. Comprising 174 Australian patients, this study identified that knowledgeable patients reported lower levels of loyalty while older patients and patients visiting a GP more frequently reported higher levels of loyalty. The results suggest that extending patient-centred care practices to encompass all patients may be warranted in order to improve patient satisfaction and loyalty. Further, future research opportunities abound, with intervention and dyadic research methodologies recommended.

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Gesture in performance is widely acknowledged in the literature as an important element in making a performance expressive and meaningful. The body has been shown to play an important role in the production and perception of vocal performance in particular. This paper is interested in the role of gesture in creative works that seek to extend vocal performance via technology. A creative work for vocal performer, laptop computer and a Human Computer Interface called the eMic (Extended Microphone Stand Interface controller) is presented as a case study, to explore the relationships between movement, voice production, and musical expression. The eMic is an interface for live vocal performance that allows the singers’ gestures and interactions with a sensor based microphone stand to be captured and mapped to musical parameters. The creative work discussed in this paper presents a new compositional approach for the eMic by working with movement as a starting point for the composition and thus using choreographed gesture as the basis for musical structures. By foregrounding the body and movement in the creative process, the aim is to create a more visually engaging performance where the performer is able to more effectively use the body to express their musical objectives.

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Background We investigated the geographical variation of water supply and sanitation indicators (WS&S) and their role to the risk of schistosomiasis and hookworm infection in school age children in West Africa. The aim was to predict large-scale geographical variation in WS&S, quantify the attributable risk of S. haematobium, S. mansoni and hookworm infections due to WS&S and identify communities where sustainable transmission control could be targeted across the region. Methods National cross-sectional household-based demographic health surveys were conducted in 24,542 households in Burkina Faso, Ghana and Mali, in 2003–2006. We generated spatially-explicit predictions of areas without piped water, toilet facilities and finished floors in West Africa, adjusting for household covariates. Using recently published helminth prevalence data we developed Bayesian geostatistical models (MGB) of S. haematobium, S. mansoni and hookworm infection in West Africa including environmental and the mapped outputs for WS&S. Using these models we estimated the effect of WS&S on parasite risk, quantified their attributable fraction of infection, and mapped the risk of infection in West Africa. Findings Our maps show that most areas in West Africa are very poorly served by water supply except in major urban centers. There is a better geographical coverage for toilet availability and improved household flooring. We estimated smaller attributable risks for water supply in S. mansoni (47%) compared to S. haematobium (71%), and 5% of hookworm cases could be averted by improving sanitation. Greater levels of inadequate sanitation increased the risk of schistosomiasis, and increased levels of unsafe water supply increased the risk of hookworm. The role of floor type for S. haematobium infection (21%) was comparable to that of S. mansoni (16%), but was significantly higher for hookworm infection (86%). S. haematobium and hookworm maps accounting for WS&S show small clusters of maximal prevalence areas in areas bordering Burkina Faso and Mali smaller. The map of S. mansoni shows that this parasite is much more wide spread across the north of the Niger River basin than previously predicted. Interpretation Our maps identify areas where the Millennium Development Goal for water and sanitation is lagging behind. Our results show that WS&S are important contributors to the burden of major helminth infections of children in West Africa. Including information about WS&S as well as the “traditional” environmental risk factors in spatial models of helminth risk yielded a substantial gain both in model fit and at explaining the proportion of spatial variance in helminth risk. Mapping the distribution of infection risk adjusted for WS&S allowed the identification of communities in West Africa where integrative preventive chemotherapy and engineering interventions will yield the greatest public health benefits.

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In late 2006, the National Library of Australia implemented a trial Instant Messaging service that ran in parallel with the AskNow chat reference service for a six month period. The trial was a resounding success, proving both a demand for an IM service and the suitability of the medium for reference service provision in a collaborative environment. The trial also allowed the collection of a significant body of data on user expectations, librarian experience and the nature of enquiries. This article begins by introducing the concept of IM and discusses the impetus for its use as a channel for reference service provision. It presents and analyses data collected from user surveys, session transcripts, usage statistics, staff surveys and other staff feedback mechanisms, and explores the issues arising from the data analysis. The article concludes by discussing the IM system architecture that the NLA is currently developing, which will allow the Library to move forward with an ongoing IM service.

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The Bcl-2-associated athanogene (BAG) family is an evolutionarily conserved, multifunctional group of cochaperones that perform diverse cellular functions ranging from proliferation to growth arrest and cell death in yeast, in mammals, and, as recently observed, in plants. The Arabidopsis genome contains seven homologs of the BAG family, including four with domain organization similar to animal BAGs. In the present study we show that an Arabidopsis BAG, AtBAG7, is a uniquely localized endoplasmic reticulum (ER) BAG that is necessary for the proper maintenance of the unfolded protein response (UPR). AtBAG7was shown to interact directly in vivo with themolecular chaperone, AtBiP2, by bimolecular fluorescence complementation assays, and the interaction was confirmed by yeast two-hybrid assay. Treatment with an inducer of UPR, tunicamycin, resulted in accelerated cell death of AtBAG7-null mutants. Furthermore, AtBAG7 knockouts were sensitive to known ER stress stimuli, heat and cold. In these knockouts heat sensitivity was reverted successfully to the wild-type phenotype with the addition of the chemical chaperone, tauroursodexycholic acid (TUDCA). Real-time PCR of ER stress proteins indicated that the expression of the heat-shock protein, AtBiP3, is selectively up-regulated in AtBAG7-null mutants upon heat and cold stress. Our results reveal an unexpected diversity of the plant's BAG gene family and suggest that AtBAG7 is an essential component of the UPR during heat and cold tolerance, thus confirming the cytoprotective role of plant BAGs.

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The single crystal Raman spectra of natural mineral finnemanite Pb5(AsO3)3Cl from the Långban locality, Filipstad district, Värmland province, Sweden are presented for the first time. It is a hexagonal mineral belonging to the ortho arsenite group, where the [AsO3]3- ion is isolated. The spectra of finnemanite are characterized by a strong band at 734 cm-1 overlying a shoulder at 726 cm-1, and broad overlapping bands in the lower wavenumber with the strongest band positioned at 174 cm-1. Band assignments were made based on band symmetry, experimental band positions from literature and DFT calculated Raman spectrum, and spectral comparison with other ortho arsenite minerals reinerite, cafarsite, and nealite and synthetic lead arsenite compounds Pb2(AsO2)3Cl, Pb2As2O5, and PbAs2O4 . The band at 734 cm-1 was assigned to υ1(AsO3), bands at 726 and 640 cm-1 assigned to υ3, 372 and 357 cm-1 to υ2, and 244, 239 and 207 cm-1 to υ4. The single crystal spectra of finnemanite showed good mode separation, allowing bands to be assigned a symmetry species of Ag, E1g, or E2g.

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Purpose: Parenting style and early feeding practices have been linked to child intake, eating behaviour and weight status. The purpose of this study was to examine associations between general maternal parenting behaviours and feeding beliefs in Australian mothers of 11-17 month-old children. Methods: This cross-sectional analysis included 223 first-time mothers and their children (49% male, mean age 14 [sd 1] months) enrolled in the control group of the NOURISH trial. Mothers self-reported their feeding beliefs and parenting behaviours (overprotection, irritability, warmth, autonomy-encouraging) using modified questions from the Infant Feeding Questionnaire (Baughcum, 2001) and the Longitudinal Study of Australian Children. Multiple regression analyses were conducted, using feeding beliefs (four factors) as dependent and parenting behaviours as independent variables while adjusting for child gender, age, weight-for-age z-score and maternal age, education level, feeding mode (breast vs. non-breast), and perception of own pre-pregnancy and child weight status. Results/Findings: Two of four parenting behaviours were significantly associated with feeding beliefs. Maternal warmth was inversely associated with concerns that the child would become underweight (β=-0.156, p=0.022) and positively associated with mothers’ awareness of child’s hunger/satiety cues (β=0.303, p<0.001). Mothers’ overprotection was positively associated with concerns that the child would become underweight (β=0.213, p=0.001); become overweight (β=0.174, p=0.005); and mother’s responsive feeding (β=0.135, p=0.057). Weight-for-age z-score, mothers’ perception of their child and own weight status, education, feeding mode, and child’s age were significant covariates. Conclusions: Feeding occurs within the broader parenting context. Improving early feeding beliefs and practices may require addressing mother’s approaches to parenting, especially warmth and overprotection.

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Determining the temporal scale of biological evolution has traditionally been the preserve of paleontology, with the timing of species originations and major diversifications all being read from the fossil record. However, the ages of the earliest (correctly identified) records will underestimate actual origins due to the incomplete nature of the fossil record and the necessity for lineages to have evolved sufficiently divergent morphologies in order to be distinguished. The possibility of inferring divergence times more accurately has been promoted by the idea that the accumulation of genetic change between modern lineages can be used as a molecular clock (Zuckerkandl and Pauling, 1965). In practice, though, molecular dates have often been so old as to be incongruent even with liberal readings of the fossil record. Prominent examples include inferred diversifications of metazoan phyla hundreds of millions of years before their Cambrian fossil record appearances (e.g., Nei et al., 2001) and a basal split between modern birds (Neoaves) that is almost double the age of their earliest recognizable fossils (e.g., Cooper and Penny, 1997).

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Camens (1) responds to our analysis of morphological data (2) in which platypuses (Ornithorhynchidae) and echidnas (Tachyglossidae) were inferred to be each other's closest relatives, to the exclusion of Early Cretaceous forms, Teinolophos and Steropodon. Our phylogeny is consistent with the late appearance of undisputed fossil echidnas and platypuses. Molecular dating provided important independent corroboration, revealing that platypuses and echidnas diverged only 19–48 Ma, implying that Teinolophos and Steropodon (105–121 Ma) must lie outside the platypus–echidna dichotomy...

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The semiaquatic platypus and terrestrial echidnas (spiny anteaters) are the only living egg-laying mammals (monotremes). The fossil record has provided few clues as to their origins and the evolution of their ecological specializations; however, recent reassignment of the Early Cretaceous Teinolophos and Steropodon to the platypus lineage implies that platypuses and echidnas diverged >112.5 million years ago, reinforcing the notion of monotremes as living fossils. This placement is based primarily on characters related to a single feature, the enlarged mandibular canal, which supplies blood vessels and dense electrosensory receptors to the platypus bill. Our reevaluation of the morphological data instead groups platypus and echidnas to the exclusion of Teinolophos and Steropodon and suggests that an enlarged mandibular canal is ancestral for monotremes (partly reversed in echidnas, in association with general mandibular reduction). A multigene evaluation of the echidna–platypus divergence using both a relaxed molecular clock and direct fossil calibrations reveals a recent split of 19–48 million years ago. Platypus-like monotremes (Monotrematum) predate this divergence, indicating that echidnas had aquatically foraging ancestors that reinvaded terrestrial ecosystems. This ecological shift and the associated radiation of echidnas represent a recent expansion of niche space despite potential competition from marsupials. Monotremes might have survived the invasion of marsupials into Australasia by exploiting ecological niches in which marsupials are restricted by their reproductive mode. Morphology, ecology, and molecular biology together indicate that Teinolophos and Steropodon are basal monotremes rather than platypus relatives, and that living monotremes are a relatively recent radiation.

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The ratite moa (Aves: Dinornithiformes) were a speciose group of massive graviportal avian herbivores that dominated the New Zealand (NZ) ecosystem until their extinction �600 years ago. The phylogeny and evolutionary history of this morphologically diverse order has remained controversial since their initial description in 1839. We synthesize mitochondrial phylogenetic information from 263 subfossil moa specimens from across NZ with morphological, ecological, and new geological data to create the first comprehensive phylogeny, taxonomy, and evolutionary timeframe for all of the species of an extinct order. We also present an important new geological/paleogeographical model of late Cenozoic NZ, which suggests that terrestrial biota on the North and South Island landmasses were isolated for most of the past 20–30 Ma. The data reveal that the patterns of genetic diversity within and between differentmoaclades reflect a complex history following a major marine transgression in the Oligocene, affected by marine barriers, tectonic activity, and glacial cycles. Surprisingly, the remarkable morphological radiation of moa appears to have occurred much more recently than previous early Miocene (ca. 15 Ma) estimates, and was coincident with the accelerated uplift of the Southern Alps just ca. 5–8.5 Ma. Together with recent fossil evidence, these data suggest that the recent evolutionary history of nearly all of the iconic NZ terrestrial biota occurred principally on just the South Island.

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In the field of process mining, the use of event logs for the purpose of root cause analysis is increasingly studied. In such an analysis, the availability of attributes/features that may explain the root cause of some phenomena is crucial. Currently, the process of obtaining these attributes from raw event logs is performed more or less on a case-by-case basis: there is still a lack of generalized systematic approach that captures this process. This paper proposes a systematic approach to enrich and transform event logs in order to obtain the required attributes for root cause analysis using classical data mining techniques, the classification techniques. This approach is formalized and its applicability has been validated using both self-generated and publicly-available logs.