1,357 research outputs found
Observations on Eimeria from Ambystoma tigrinum, with Descriptions of Four New Species
There appear to be only three records of coccidia of the genus Ezmeria from North American Amphibia. Rankin (1937) reported Eimeria ranarum from Ambystoma opacum. Walton (personal communication) says that his record (1942) of Eimeria from Ambystoma is based upon a letter from Dr. Harold Kirby who stated that he had seen E. ranarum from A. opacum. Doran (1953) reported Eimeria grobbeni from Taricha torosa. The author, on several occasions, has noted the presence of coccidian oocysts in the rectal contents of salamanders. Four species of Eimeria have been recognized in material from Ambystoma tigrinum (Green) and will be described as new
Trimitus parvus Grasse (Protozoa, Mastigophora) from a garter snake, Thamnophis radix
Reptiles collected in the vicinity of the Iowa Lakeside Laboratory, Dickinson County, Iowa, during the summer of 1950, were examined for helminths by Burnham (1951) and for protozoa by Schmidt (1954). lvlonocercomonas colubrorum, Trichomonas batrachorum and Haemogregarina sp. were found in both Thamnophis radix and T. ordinatus parietalis. An enteric flagellate of the genus Trimitus was found in a single specimen of T. radix. Special consideration is herein given to Trimitus because though this genus has been reported from North American amphibians and reptiles it appears that neither descriptions nor figures have been published, and also, because there is some uncertainty concerning the characterization of the genus
Greenhouse gas considerations in rail infrastructure in the UK
Transportation-related greenhouse gas (GHG) emissions account for an increasing proportion of total emissions in the UK and globally. The provision of rail transit is popularly proposed to reduce transport GHG emissions, but the provision of new infrastructure is itself GHG intensive. Understanding of the GHG emissions impact of rail projects is limited and very few longitudinal studies have been carried out. Existing assessments are often limited both in their scope and the factors considered. A holistic understanding of GHG impacts must include an assessment of capital GHG emissions, operational energy and maintenance as well as an assessment of ridership mode shift and mode share impacts and the relationship between transit infrastructure and land use. This paper explores rail infrastructure projects and their associated GHG emissions. Guidance is given on the aspects of rail planning, design and construction that must be considered to more fully understand the associated GHG impacts.The authors would like to thank The Commonwealth Scholarship Commission in the UK for the scholarship funding that facilitated this work
Response patterns in the developing social brain are organized by social and emotion features and disrupted in children diagnosed with autism spectrum disorder
© 2019 Elsevier Ltd Adults and children recruit a specific network of brain regions when engaged in âTheory of Mindâ (ToM) reasoning. Recently, fMRI studies of adults have used multivariate analyses to provide a deeper characterization of responses in these regions. These analyses characterize representational distinctions within the social domain, rather than comparing responses across preferred (social) and non-preferred stimuli. Here, we conducted opportunistic multivariate analyses in two previously collected datasets (Experiment 1: n = 20 5â11 year old children and n = 37 adults; Experiment 2: n = 76 neurotypical and n = 29 5â12 year old children diagnosed with Autism Spectrum Disorder (ASD)) in order to characterize the structure of representations in the developing social brain, and in order to discover if this structure is disrupted in ASD. Children listened to stories that described characters' mental states (Mental), non-mentalistic social information (Social), and causal events in the environment (Physical), while undergoing fMRI. We measured the extent to which neural responses in ToM brain regions were organized according to two ToM-relevant models: 1) a condition model, which reflected the experimenter-generated condition labels, and 2) a data-driven emotion model, which organized stimuli according to their emotion content. We additionally constructed two control models based on linguistic and narrative features of the stories. In both experiments, the two ToM-relevant models outperformed the control models. The fit of the condition model increased with age in neurotypical children. Moreover, the fit of the condition model to neural response patterns was reduced in the RTPJ in children diagnosed with ASD. These results provide a first glimpse into the conceptual structure of information in ToM brain regions in childhood, and suggest that there are real, stable features that predict responses in these regions in children. Multivariate analyses are a promising approach for sensitively measuring conceptual and neural developmental change and individual differences in ToM.NSF (Award 1122374
Reduced neural selectivity for mental states in deaf children with delayed exposure to sign language
Early linguistic experience directly facilitates social development in childhood. Here, the authors reveal that children with delayed access to language show delayed development of selective responses in cortical regions involved in thinking about othersâ thoughts
Reproducibility in high-throughput density functional theory: a comparison of AFLOW, Materials Project, and OQMD
A central challenge in high throughput density functional theory (HT-DFT)
calculations is selecting a combination of input parameters and post-processing
techniques that can be used across all materials classes, while also managing
accuracy-cost tradeoffs. To investigate the effects of these parameter choices,
we consolidate three large HT-DFT databases: Automatic-FLOW (AFLOW), the
Materials Project (MP), and the Open Quantum Materials Database (OQMD), and
compare reported properties across each pair of databases for materials
calculated using the same initial crystal structure. We find that HT-DFT
formation energies and volumes are generally more reproducible than band gaps
and total magnetizations; for instance, a notable fraction of records disagree
on whether a material is metallic (up to 7%) or magnetic (up to 15%). The
variance between calculated properties is as high as 0.105 eV/atom (median
relative absolute difference, or MRAD, of 6%) for formation energy, 0.65
{\AA}/atom (MRAD of 4%) for volume, 0.21 eV (MRAD of 9%) for band gap, and
0.15 /formula unit (MRAD of 8%) for total magnetization,
comparable to the differences between DFT and experiment. We trace some of the
larger discrepancies to choices involving pseudopotentials, the DFT+U
formalism, and elemental reference states, and argue that further
standardization of HT-DFT would be beneficial to reproducibility.Comment: Authors VIH and CKHB contributed equally to this wor
Controlling the accuracy of the density matrix renormalization group method: The Dynamical Block State Selection approach
We have applied the momentum space version of the Density Matrix
Renormalization Group method (-DMRG) in quantum chemistry in order to study
the accuracy of the algorithm in the new context. We have shown numerically
that it is possible to determine the desired accuracy of the method in advance
of the calculations by dynamically controlling the truncation error and the
number of block states using a novel protocol which we dubbed Dynamical Block
State Selection (DBSS). The relationship between the real error and truncation
error has been studied as a function of the number of orbitals and the fraction
of filled orbitals. We have calculated the ground state of the molecules
CH, HO, and F as well as the first excited state of CH. Our
largest calculations were carried out with 57 orbitals, the largest number of
block states was 1500--2000, and the largest dimensions of the Hilbert space of
the superblock configuration was 800.000--1.200.000.Comment: 12 page
Follow-up after paediatric intensive care treatment: parental postraumatic stress
Aim: To study the prevalence of posttraumatic stress in parents after an acute admission to a paediatric intensive care unit (PICU) and to determine risk factors for the development of posttraumatic stress. Methods: Parents completed posttraumatic stress questionnaires three months after their child's discharge. This questionnaire measures both symptoms of posttraumatic stress disorder (PTSD) and enables determination of the full psychiatric diagnosis of PTSD. Medical and demographic data concerning their child were gathered from physical evaluations three months after discharge. Of 250 eligible families, 144 (57.6%) participated in this study. The questionnaires were completed by 140 mothers and 107 fathers. Results: More than three-quarters of the parents experienced persistent symptoms of PTSD. In 21 mothers (15.0%) and 10 fathers (9.3%), the full psychiatric diagnosis of PTSD was determined. In six families, both parents had PTSD. Furthermore, a significant positive correlation was found between symptoms of PTSD of the mothers and the fathers. No obvious medical risk factors could be distinguished. Conclusion: The unexpected admission of a child to a PICU is a stressful event associated with parental posttraumatic stress. Treatment should not end after discharge. Follow-up care is warranted and research should be focused on prevention of these symptoms. © 2007 The Author(s)
Recent advances in electronic structure theory and their influence on the accuracy of ab initio potential energy surfaces
Recent advances in electronic structure theory and the availability of high speed vector processors have substantially increased the accuracy of ab initio potential energy surfaces. The recently developed atomic natural orbital approach for basis set contraction has reduced both the basis set incompleteness and superposition errors in molecular calculations. Furthermore, full CI calculations can often be used to calibrate a CASSCF/MRCI approach that quantitatively accounts for the valence correlation energy. These computational advances also provide a vehicle for systematically improving the calculations and for estimating the residual error in the calculations. Calculations on selected diatomic and triatomic systems will be used to illustrate the accuracy that currently can be achieved for molecular systems. In particular, the F+H2 yields HF+H potential energy hypersurface is used to illustrate the impact of these computational advances on the calculation of potential energy surfaces
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