655 research outputs found
Sonographically detected costo-chondral dislocation in an abused child - A new sonographic sign to the radiological spectrum of child abuse
A case of an abused child with fractures of the skull, ribs and long bones is presented. Sonographically a costochondral dislocation of the left lower ribs was detected, which has not been reported in the literature
Brookite versus anatase TiO2 photocatalysts: Phase transformations and photocatalytic activities
Titanium dioxide nanoparticles consisting of pure anatase, anatase-rich, brookite-rich, and pure brookite modifications were synthesized and characterized by X-ray diffraction, field emission-scanning electron microscopy and nitrogen adsorption. The phase transformations among the three modifications of TiO2 (anatase, brookite, and rutile) and the photocatalytic activities of these nanoparticles were investigated by heat treatment over the temperature range from 400 to 800 °C and by the photooxidation of methanol, respectively. Direct transformation of anatase and brookite to rutile was observed, while in the case of the anatase–brookite mixture, anatase transforms firstly to brookite and then to rutile. The photocatalytic activity measurements indicate that brookite nanoparticles exhibit higher photocatalytic activities than anatase, and a comparable activity to that of the anatase-rich nanoparticles. The phase transformations and photocatalytic results are discussed regarding their dependence on crystallite size, surface area, and phase composition
Prediction of final infarct volume from native CT perfusion and treatment parameters using deep learning
CT Perfusion (CTP) imaging has gained importance in the diagnosis of acute
stroke. Conventional perfusion analysis performs a deconvolution of the
measurements and thresholds the perfusion parameters to determine the tissue
status. We pursue a data-driven and deconvolution-free approach, where a deep
neural network learns to predict the final infarct volume directly from the
native CTP images and metadata such as the time parameters and treatment. This
would allow clinicians to simulate various treatments and gain insight into
predicted tissue status over time. We demonstrate on a multicenter dataset that
our approach is able to predict the final infarct and effectively uses the
metadata. An ablation study shows that using the native CTP measurements
instead of the deconvolved measurements improves the prediction.Comment: Accepted for publication in Medical Image Analysi
Fourier transform microwave spectroscopy of Ac-Ser-NH2: the role of side chain interactions in peptide folding
Serine capped dipeptide N-acetyl-L-serinamide (Ac-Ser-NH2) has been investigated using Fourier transform microwave spectroscopic techniques combined with laser ablation sources. Spectral signatures originating from one dominant species have been detected in the supersonic expansion. Rotational and nuclear quadrupole coupling constants of the two 14N nuclei have been used in the characterization of a Ceq/g-turn structure, which is stabilized by a C7O·· ·HN intramolecular hydrogen bond closing a seven-membered ring. Two extra hydrogen bonds involving the polar side chain (–CH2OH) further stabilize the structure. The non-observation of C5 species, attributed to the presence of the polar side chain, is in contrast with the previous gas phase observation of the related dipeptides containing glycine or alanine residues. The A–E splitting pattern arising from the internal rotation of the methyl group has been analyzed and the internal rotation barrier has been determined
Strain-dependent host transcriptional responses to toxoplasma infection are largely conserved in mammalian and avian hosts
Toxoplasma gondii has a remarkable ability to infect an enormous variety of mammalian and avian species. Given this, it is surprising that three strains (Types I/II/III) account for the majority of isolates from Europe/North America. The selective pressures that have driven the emergence of these particular strains, however, remain enigmatic. We hypothesized that strain selection might be partially driven by adaptation of strains for mammalian versus avian hosts. To test this, we examine in vitro, strain-dependent host responses in fibroblasts of a representative avian host, the chicken (Gallus gallus). Using gene expression profiling of infected chicken embryonic fibroblasts and pathway analysis to assess host response, we show here that chicken cells respond with distinct transcriptional profiles upon infection with Type II versus III strains that are reminiscent of profiles observed in mammalian cells. To identify the parasite drivers of these differences, chicken fibroblasts were infected with individual F1 progeny of a Type II x III cross and host gene expression was assessed for each by microarray. QTL mapping of transcriptional differences suggested, and deletion strains confirmed, that, as in mammalian cells, the polymorphic rhoptry kinase ROP16 is the major driver of strain-specific responses. We originally hypothesized that comparing avian versus mammalian host response might reveal an inversion in parasite strain-dependent phenotypes; specifically, for polymorphic effectors like ROP16, we hypothesized that the allele with most activity in mammalian cells might be less active in avian cells. Instead, we found that activity of ROP16 alleles appears to be conserved across host species; moreover, additional parasite loci that were previously mapped for strain-specific effects on mammalian response showed similar strain-specific effects in chicken cells. These results indicate that if different hosts select for different parasite genotypes, the selection operates downstream of the signaling occurring during the beginning of the host's immune response. © 2011 Ong et al
Literator 2010: Daniel Kehlmann. Dozentur für Weltliteratur
"Sollen doch die Literaturwissenschaftler sich damit beschäftigen, etwas Übersehenes zu finden, der Literat aber darf sich auch einmal den Luxus erlauben, über das Beliebteste zu sprechen, also jenes weltgewinnende Werk, das für immer das Bild eines Kontinents verändert hat. Südamerika, so ließ García Márquez einst jemanden in seiner frühen Novelle Der Oberst hat niemand, der ihm schreibt klagen, das sei für die meisten Menschen doch nur ein Mann mit Schnurrbart, Gitarre und Pistole. Das stimmte dereinst sicher, aber heute ist Südamerika eher ein unheimliches Haus, umgeben von Moor und buntem Regenwald, ein Land bizarrer und melancholischer Wunder. Unsere Vorstellungen sind hier so sehr durch einen einzigen Roman geprägt, dass wir es kaum mehr bemerken." Daniel Kehlman
‘Like the stranger at a funeral who cries more than the bereaved’: ethical dilemmas in ethnographic research with children
This article contributes to debates on the practicality and utility of prior ethical review in ethnography and qualitative research using an ethnography of children’s involvement in artisanal gold mining work in Ghana as a case study. Reflecting on dilemmas and obstacles encountered in attempts to employ prescribed institutional ethical guidance modelled for childhood research in the UK during the fieldwork, the discussion brings to attention some of the problems that can arise when ethical guidance is not anchored in the lived realities or value systems of the setting in which fieldwork is conducted. The article seeks to rejuvenate calls for more flexible and socio-culturally responsive ethical review and practice as an alternative to the prescriptive ethical regimes
An Examination of the Dutch health care inspectorate's supervision system for suicides of mental health care users
OBJECTIVE: This study examined characteristics of suicides among mental health care users reported between 1996 and 2006 to the Dutch Health Care Inspectorate and the inspectorate's follow-up responses. The aims were to determine whether follow-up was associated with particular characteristics and whether the responses could be improved in accordance with guidelines for treatment of suicidal patients. METHODS: Information about patient and treatment characteristics was collected from a sample of 505 of the 5,483 suicide notifications between 1996 and 2006. The 1996–2005 sample included an equal number of cases to which the inspectorate did and did not respond. The 2006 sample included the first 205 notifications in that year. RESULTS: For 2006 notifications the response rate was 37%. The responses most frequently addressed how and whether the suicide was evaluated and the adequacy of treatment for the psychiatric disorder. A follow-up response was more likely when the suicide involved a young patient or a patient treated in a mental health care setting for less than a year or when the notification was accompanied by the mental health institution's plans for improving its policies. A response was less likely when the patient was discharged from inpatient care in the three months before the suicide. Since 2002 responses have more frequently emphasized the importance of suicide risk assessment, in accordance with guidelines. CONCLUSIONS: The inspectorate might improve its supervision system by placing greater emphasis on addressing suicidal impulses and treating older and chronically suicidal patients and patients soon after inpatient discharge
Selection at a single locus leads to widespread expansion of toxoplasma gondii lineages that are virulent in mice
The determinants of virulence are rarely defined for eukaryotic parasites such as T. gondii, a widespread parasite of mammals that also infects humans, sometimes with serious consequences. Recent laboratory studies have established that variation in a single secreted protein, a serine/threonine kinase known as ROPO18, controls whether or not mice survive infection. Here, we establish the extent and nature of variation in ROP18among a collection of parasite strains from geographically diverse regions. Compared to other genes, ROP18 showed extremely high levels of diversification and changes in expression level, which correlated with severity of infection in mice. Comparison with an out-group demonstrated that changes in the upstream region that regulates expression of ROP18 led to an historical increase in the expression and exposed the protein to diversifying selective pressure. Surprisingly, only three atypically distinct protein variants exist despite marked genetic divergence elsewhere in the genome. These three forms of ROP18 are likely adaptations for different niches in nature, and they confer markedly different virulence to mice. The widespread distribution of a single mouse-virulent allele among geographically and genetically disparate parasites may have consequences for transmission and disease in other hosts, including humans
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