365 research outputs found

    pH sensor properties of electrochemically grown iridium oxide

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    The open-circuit potential of an electrochemically grown iridium oxide film is measured and shows a pH sensitivity between −60 and −80 mV/pH. This sensitivity is found to depend on the state of oxidation of the iridium oxide film; for a higher state of oxidation (or more of the oxide in the high valence state), the sensitivity is also higher. This high sensitivity can be explained on the basis of the extra proton release as a result of the acidic character of the porous hydrous oxyhydroxide, in combination with the redox behaviour.\ud \ud The response time to a pH step is measured and is found to depend mainly on the thickness of the oxide; it varies from 40 ms to 0.35 s due to the porous nature of the film.\ud \ud Drift measurements show that an iridium oxide film in reduced state is slowly oxidized by dissolved oxygen, whereas a pre-oxidized film in a pH = 4.01 buffer solution in contact with air shows a long-term drift of <0.3 mV/h

    Mechanism and function of drosophila capa GPCR: a desiccation stress-responsive receptor with functional homology to human neuromedinU receptor

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    The capa peptide receptor, capaR (CG14575), is a G-protein coupled receptor (GPCR) for the D. melanogaster capa neuropeptides, Drm-capa-1 and -2 (capa-1 and -2). To date, the capa peptide family constitutes the only known nitridergic peptides in insects, so the mechanisms and physiological function of ligand-receptor signalling of this peptide family are of interest. Capa peptide induces calcium signaling via capaR with EC50 values for capa-1 = 3.06 nM and capa-2 = 4.32 nM. capaR undergoes rapid desensitization, with internalization via a b-arrestin-2 mediated mechanism but is rapidly re-sensitized in the absence of capa-1. Drosophila capa peptides have a C-terminal -FPRXamide motif and insect-PRXamide peptides are evolutionarily related to vertebrate peptide neuromedinU (NMU). Potential agonist effects of human NMU-25 and the insect -PRLamides [Drosophila pyrokinins Drm-PK-1 (capa-3), Drm-PK-2 and hugin-gamma [hugg]] against capaR were investigated. NMU-25, but not hugg nor Drm-PK-2, increases intracellular calcium ([Ca2+]i) levels via capaR. In vivo, NMU-25 increases [Ca2+]i and fluid transport by the Drosophila Malpighian (renal) tubule. Ectopic expression of human NMU receptor 2 in tubules of transgenic flies results in increased [Ca2+]i and fluid transport. Finally, anti-porcine NMU-8 staining of larval CNS shows that the most highly immunoreactive cells are capa-producing neurons. These structural and functional data suggest that vertebrate NMU is a putative functional homolog of Drm-capa-1 and -2. capaR is almost exclusively expressed in tubule principal cells; cell-specific targeted capaR RNAi significantly reduces capa-1 stimulated [Ca2+]i and fluid transport. Adult capaR RNAi transgenic flies also display resistance to desiccation. Thus, capaR acts in the key fluid-transporting tissue to regulate responses to desiccation stress in the fly

    Is there a mismatch between the perspectives of patients and regulators on healthcare quality?:A survey study

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    Objectives: Internationally, healthcare quality regulators are criticized for failing to respond to patients' complaints. Patient involvement is, therefore, an important item on the policy agenda. However, it can be argued that there is a discrepancy between the patients' perspective and current regulatory approaches. This study examines whether a discrepancy exists between the perspectives of patients and regulators on healthcare quality. Methods: A questionnaire was sent to 996 people who had registered a complaint with the Dutch Healthcare Inspectorate to measure expectations of and experiences with the Inspectorate. A taxonomy was used to classify their complaints into the clinical, relationship, or management domains. Results: The response was 54%. More complaints about clinical issues (56%, P = 0.000) were investigated by the regulator than complaints about organizational (37%) and relational issues (51%). Patients with complaints about management issues less often indicated (13%, P = 0.002) that healthcare is improved by making their complaint than patients with complaints about clinical or relationship issues did (22%–23%). Patients who reported about relational issues with care providers attached more importance to issuing sanctions against the care provider than other patients (mean score 2.89 versus 2.62–2.68, P = 0.006). Conclusions: The predominant clinical approach taken by regulators does not match the patients' perspective of what is relevant for healthcare quality. In addition, patients seem to be more tolerant of what they perceive to be clinical or management errors than of perceived relational deficiencies in care providers. If regulators want to give patients a voice, they should expand their horizon beyond the medical framework

    Needy or Greedy? The Social Psychology of Individuals Who Fraudulently Claim Unemployment Benefits

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    This study explored the relationships between diverse social psychological and economic variables and self‐reported and officially documented unemployment benefit fraud. Two groups receiving unemployment benefit were studied; a fraudulent group of 45 individuals and an honest group of 51 individuals. Interview measures of financial strain, social norms, opportunity for fraud, social controls, personal strain, personal orientation, perceived risk of punishment, and intolerance of fraud were obtained. The results of univariate and regression analyses revealed that although financial strain and social norms did not differ between the two groups, the fraudulent group had more opportunity, were less well educated, were more alienated and inclined to take risks, and had more positive attitudes toward a variety of kinds of fraud. Copyrigh

    Systemic risk approach to mitigate delay cascading in railway networks

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    In public railway systems, minor disruptions can trigger cascading events that lead to delays in the entire system. Typically, delays originate and propagate because the equipment is blocking ways, operational units are unavailable, or at the wrong place at the needed time. The specific understanding of the origins and processes involved in delay-spreading is still a challenge, even though large-scale simulations of national railway systems are becoming available on a highly detailed scale. Without this understanding, efficient management of delay propagation, a growing concern in some Western countries, will remain impossible. Here, we present a systemic risk-based approach to manage daily delay cascading on national scales. We compute the {\em systemic impact} of every train as the maximum of all delays it could possibly cause due to its interactions with other trains, infrastructure, and operational units. To compute it, we design an effective impact network where nodes are train services and links represent interactions that could cause delays. Our results are not only consistent with highly detailed and computationally intensive agent-based railway simulations but also allow us to pinpoint and identify the causes of delay cascades in detail. The systemic approach reveals structural weaknesses in railway systems whenever shared resources are involved. We use the systemic impact to optimally allocate additional shared resources to the system to reduce delays with minimal costs and effort. The method offers a practical and intuitive solution for delay management by optimizing the effective impact network through the introduction of new cheap local train services.Comment: 27 pages, 14 figure

    Toezien op zorgkwaliteit door de ogen van patiënten:Andere werkwijze van inspectie nodig

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    De inspectie gezondheidszorg en Jeugd (ig J) wil het per- spectief van patiënten meer betrekken bij haar toezicht. Burgermeldingen geven de inspectie inzicht in dit patiën- tenperspectief. Patiënten die klachten melden willen dat het probleem dat zij melden zich niet herhaalt, maar het overgrote deel van die meldingen wordt niet nader onder- zocht door de inspectie. Daarnaast worden meldingen met een klinisch aspect veel vaker onderzocht dan organisatori- sche of communicatieve problemen. Bij meldingen van pati- enten gaat het niet noodzakelijkerwijs om het afwijken van de professionele richtlijnen met schade als gevolg. Als de inspectie kwaliteit van zorg door het perspectief van de patiënt wil bekijken, kan zij het beeld dat de patiënt hun aanreikt serieuzer nemen. Het patiëntenperspectief sugge- reert dat het voor de inspectie van belang is meer aandacht te besteden aan organisatorische factoren, relationele aspecten en andere aspecten van de gezondheidszorg, naast de medisch professionele normen

    ‘Like the stranger at a funeral who cries more than the bereaved’: ethical dilemmas in ethnographic research with children

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    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

    Changes in globus pallidus with (pre)term kernicterus

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    OBJECTIVE: We report serial magnetic resonance (MR) and sonographic behavior of globus pallidus in 5 preterm and 3 term infants with kernicterus and describe the clinical context in very low birth weight preterm infants. On the basis of this information, we suggest means of diagnosis and prevention. METHODS: Charts and MR and ultrasound images of 5 preterm infants and 3 term infants with suspected bilirubin-associated brain damage were reviewed. Included were preterm infants with severe hearing loss, quadriplegic hypertonia, and abnormal hypersignal of globus pallidus on T2-weighted MR imaging (MRI). In 1 infant who died on day 150, the diagnosis was confirmed during the neonatal period. The others were picked up as outpatients and scanned at 12 or 22 months' corrected age. Three instances of term kernicterus were included for comparison of serial MRI in the neonatal period and early infancy: they were caused by glucose-6-phosphate dehydrogenase deficiency, urosepsis, and dehydration plus fructose 1-6 biphosphatase deficiency. RESULTS: Five preterm infants of 25 to 29 weeks' gestational age presented with total serum bilirubin (TSB) levels below exchange transfusion thresholds commonly advised. Mixed acidosis was present in 3 infants around the TSB peak. The bilirubin/albumin molar ratio was >0.5 in all, in the absence of displacing drugs. All failed to pass bedside hearing screen tests and had severe hearing loss on auditory brain response testing. Symmetrical homogeneous hyperechogenicity of globus pallidus was the alerting feature in 1 infant. Globus pallidus was hyperintense on T1-weighted MR images in this child. The other infants presented with severe developmental delay as a result of dyskinetic quadriplegia and hearing loss. Globus pallidus was normal on T1- but hyperintense on T2-weighted MR images at 12

    Strain-dependent host transcriptional responses to toxoplasma infection are largely conserved in mammalian and avian hosts

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    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

    Evidence of a sudden increase in α-chloralose poisoning in dogs and cats in the Netherlands between 2018 and 2021

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    BACKGROUND: After changes in European Union biocide legislation, the Dutch Poisons Information Center observed a strong increase in information requests concerning dogs and cats exposed to α-chloralose. To investigate whether α-chloralose-based rodenticides are safe for non-professional use, additional information regarding poisoning scenarios and clinical course was collected. METHODS: Veterinarians reporting α-chloralose exposure over a 2.5-year period were contacted by mail for follow-up information concerning exposure scenario, product formulation, clinical course and treatment, and outcome. In total, information was collected for 96 dogs and 41 cats. RESULTS: Fifty-three of 96 dogs and 17 of 19 cats known to have been exposed to α-chloralose-based rodenticides developed signs of central nervous system (CNS) depression or sensory-induced CNS excitation. Mortality in dogs and cats following exposure was 1% and 18%, respectively. An additional 22 cats presented with clinical signs suggestive of α-chloralose poisoning, with a mortality of 5%. LIMITATIONS: Exposure to α-chloralose was not confirmed by biochemical analyses. CONCLUSION: Dogs and especially cats were at risk of poisoning from α-chloralose. If criteria such as acute toxicity and risk of (secondary) poisoning are applied during the approval of α-chloralose-based rodenticides, similar to anticoagulant-based rodenticides, it can be concluded that α-chloralose is also not safe for non-professional use
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