976 resultados para initial condition
The nitric oxide ISO photocatalytic reactor system: Measurement of NOx removal activity and capacity
Resumo:
Although the NO removal-based air-purification ISO method ISO 22197-1:2007 is well established, its preconditioning requirements mean that only the initial activity of the photocatalyst under test is measured owing to the often-reported, gradual alteration of the surface kinetics for NO oxidation by air through the accumulation of surface HNO3. Herein, we compare the photocatalytic NO removal abilities of a number of different, common TiO2 materials, surface-saturated with photogenerated HNO3, with their behaviours observed during the typical 5 h-long ISO standard test. It is found that all the TiO2 materials studied eventually become largely NO to NO2 converters after sufficient exposure to NO under irradiation (>5 h) due to the accumulation of surface HNO3. The UV exposure time, t*, necessary to reach this HNO3 saturated condition is different for each different catalyst. As a consequence, an alternative preconditioning process for the ISO method is proposed which can be used to provide a more realistic measure of the photocatalytic activity of the underlying material and provide a measure of the NOx removing capacity of the photocatalytic material under test.
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A potential standard method for measuring the relative dissolution rate to estimate the resorbability of calcium-phosphate-based ceramics is proposed. Tricalcium phosphate (TCP), magnesium-substituted TCP (MgTCP) and zinc-substituted TCP (ZnTCP) were dissolved in a buffer solution free of calcium and phosphate ions at pH 4.0, 5.5 or 7.3 at nine research centers. Relative values of the initial dissolution rate (relative dissolution rates) were in good agreement among the centers. The relative dissolution rate coincided with the relative volume of resorption pits of ZnTCP in vitro. The relative dissolution rate coincided with the relative resorbed volume in vivo in the case of comparison between microporous MgTCPs with different Mg contents and similar porosity. However, the relative dissolution rate was in poor agreement with the relative resorbed volume in vivo in the case of comparison between microporous TCP and MgTCP due to the superimposition of the Mg-mediated decrease in TCP solubility on the Mg-mediated increase in the amount of resorption. An unambiguous conclusion could not be made as to whether the relative dissolution rate is predictive of the relative resorbed volume in vivo in the case of comparison between TCPs with different porosity. The relative dissolution rate may be useful for predicting the relative amount of resorption for calcium-phosphate-based ceramics having different solubility under the condition that the differences in the materials compared have little impact on the resorption process such as the number and activity of resorbing cells.
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Respiratory viral infections are a common cause of acute coughing, an irritating symptom for the patient and an important mechanism of transmission for the virus. Although poorly described, the inflammatory consequences of infection likely induce coughing by chemical (inflammatory mediator) or mechanical (mucous) activation of the cough-evoking sensory nerves that innervate the airway wall. For some individuals, acute cough can evolve into a chronic condition, in which cough and aberrant airway sensations long outlast the initial viral infection. This suggests that some viruses have the capacity to induce persistent plasticity in the neural pathways mediating cough. In this brief review we present the clinical evidence of acute and chronic neural dysfunction following viral respiratory tract infections and explore possible mechanisms by which the nervous system may undergo activation, sensitization and plasticity.
Resumo:
Background
Therapist responses to initial shame disclosure in therapy have received little empirical attention.
Aim
This study explored different therapeutic responses to shame disclosures in terms of their perceived helpfulness. Responses ranged from complete withdrawal from the feeling (withdrawal) to completely tuning into it (non-withdrawal). Given the tendency of shame to evoke avoidance, participants higher on shame-proneness (as measured by The Experience of Shame Scale) were expected to perceive withdrawal responses to shame as more helpful than non-withdrawal responses.
Methodology
Fifty-five non-clinical participants were assessed for shame-proneness before viewing videos of mock therapy sessions showing clients either disclosing shame (two videos) or shock (control condition). Participants then rated the helpfulness of different therapist responses. The responses differed in the degree they allowed the client to withdraw from their emotions.
Results
High shame proneness was associated with rating withdrawal responses to shame as least helpful. Overall, neither the withdrawal response nor the non-withdrawal response were rated as particularly helpful. The therapeutic response which addressed management strategies when shame is initially experienced in therapy was deemed most helpful.
Conclusion
Despite the tendency to withdraw from shame feelings, this response is not deemed helpful in therapy.
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Objectives Chronic MRSA infection, which affects approximately 26% of CF patients in the USA, is associated with declining lung function and poor outcomes (Dasenbrook, 2010). Anaerobic niches have been described within the CF lung, potentially influencing the virulence of MRSA. This study aims to compare initial and chronic CF MRSA isolates, following aerobic and anaerobic culture. Methods Isolates, obtained from CF sputum at first isolation [“early” (n = 10)] or up to 5 years later, during chronic infection [“late” (n = 15)] were cultured in aerobic and anaerobic conditions. Differences in virulence were compared using the Galleria mellonella infection model. Biofilm formation of each isolate was assessed following staining with crystal violet. Production of Δ-haemolysin (Δ-hly), a surrogate marker for expression of the virulence regulator agr, was determined by haemolysis assay. Results MRSA grown in anaerobic conditions had significantly increased virulence in the G. mellonella model (p = 0.007), increased biofilm formation (p = 0.006) and increased Δ-hly production (p<0.0001). No significant difference between Δ-hly production or biofilm formation were observed between early and late isolates; however late isolates were found to be more virulent in the G. mellonella model (p = 0.0002). Conclusion These results suggest that an anaerobic environment, as found in the CF lung, may increase virulence of MRSA and aid in the establishment of chronic infection. Further clinical studies are required to determine how these phenotypic changes are associated with transition to chronic infection and patient outcome.
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We develop a framing for research on the relationship between context, process and outcomes in recruitment to the teaching profession. We do this through a ‘home international’ comparison of policies, outcomes and recruitment processes in England, Northern Ireland, Scotland and Wales. There is plenty of movement between these countries in the graduate labour market, but the contexts for teacher supply and demand vary in terms of: (i) scale, (ii) excess supply or demand, (iii) reliance of policy on market forces or bureaucracy and (iv) beliefs of policymakers about whether teaching is a craft or a profession. Recent changes in England and Wales have highlighted the importance of recruitment to initial teacher education (ITE as a policy issue whilst also creating further points of comparison which are useful for research. We draw on trends in data on recruitment to teaching and in-depth interviews with gatekeepers to the profession in each country.
On analytical derivations of the condition number distributions of dual non-central Wishart matrices
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A significant portion of the UK’s transportation system relies on a network of geotechnical earthworks (cuttings and embankments) that were constructed more than 100 years ago, whose stability is affected by the change in precipitation patterns experienced over the past few decades. The vulnerability of these structures requires a reliable, cost- and time-effective monitoring of their geomechanical condition. We have assessed the potential application of P-wave refraction for tracking the seasonal variations of seismic properties within an aged clay-filled railway embankment, located in southwest England. Seismic data were acquired repeatedly along the crest of the earthwork at regular time intervals, for a total period of 16 months. P-wave first-break times were picked from all available recorded traces, to obtain a set of hodocrones referenced to the same spatial locations, for various dates along the surveyed period of time. Traveltimes extracted from each acquisition were then compared to track the pattern of their temporal variability. The relevance of such variations over time was compared with the data experimental uncertainty. The multiple set of hodocrones was subsequently inverted using a tomographic approach, to retrieve a time-lapse model of VPVP for the embankment structure. To directly compare the reconstructed VPVP sections, identical initial models and spatial regularization were used for the inversion of all available data sets. A consistent temporal trend for P-wave traveltimes, and consequently for the reconstructed VPVP models, was identified. This pattern could be related to the seasonal distribution of precipitation and soil-water content measured on site.
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PURPOSE: To compare initial glaucoma therapy with medications and trabeculectomy in southern India. METHODS: Patients aged ≥ 30 years newly diagnosed with glaucoma were randomized to trabeculectomy with 5-fluorouracil or medical therapy. Subjects with best-corrected vision <6/18 due to cataract underwent phacoemulsification (phaco/intraocular lens, IOL). Intraocular pressure (IOP), vision and visual function were assessed at 12 months. RESULTS: Patients assigned to medications and surgery received the expected therapy in 86% (172/199) and 64% (126/199) of cases, respectively. Forty patients (20%) assigned to surgery refused any treatment and 33 (17%) received medications. Among 199 patients randomized to medications, 52 (26.1%) underwent phaco/IOL, as did 89/199 (43.7%) of patients randomized to trabeculectomy. Baseline parameters of the two groups did not differ, nor did 1-year follow-up rates (medication 65%, trabeculectomy 58%, P = 0.15). Final IOP was lower with randomization to trabeculectomy (16.3 ± 5.1 mmHg) than medication (18.8 ± 6.7 mmHg, P < 0.0001). In regression models, randomization to trabeculectomy (P < 0.0001) was associated with lower IOP, and simultaneous trabeculectomy and cataract surgery was associated with higher IOP (P = 0.008) than trabeculectomy alone. Subjects receiving Phaco/IOL had significantly better final acuity (P < 0.0001) and visual function (P = 0.035), despite concurrent glaucoma treatment. Final visual acuity was worse in those receiving trabeculectomy in addition to cataract surgery, but this was of borderline significance (P = 0.06). CONCLUSIONS: Trabeculectomy lowered IOP significantly more than medical treatment, but with slightly greater loss of visual acuity. Combined phaco/IOL and trabeculectomy improved visual acuity with substantial IOP lowering.
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Cuttings in heavily overconsolidated clays are known to be susceptible to progressive deformation caused by creep and fatigue that usually begins at the toe of the slope. The progressive deformation leads to strength reduction with time at constant stress (or called softening) and could be accelerated by fluctuation of groundwater level associated with more extreme rainfall events predicted through climate change. The purpose of this paper is to assess the mechanism of progressive deformation due to creep and fatigue using element testing on samples of till. The samples were subjected to fully drained loading and the deviator stresses were held constant at various percentages of peak failure stress, while the pore water pressure was kept static or dynamic (fluctuating ±5 kPa) over a period of time. The results have shown that the samples experienced significant deformation even at a higher factor of safety (i.e. the failure deviator stress/deviator stress at which the pore water pressure was fluctuated) under pore water pressure dynamics.
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Acute respiratory infections are the leading cause of global child mortality. In the developing world, nasal oxygen therapy is often the only treatment option for babies who are suffering from respiratory distress. Without the added pressure of bubble Continuous Positive Airway Pressure (bCPAP) which helps maintain alveoli open, babies struggle to breathe and can suffer serious complications, and frequently death. A stand-alone bCPAP device can cost $6,000, too expensive for most developing world hospitals. Here, we describe the design and technical evaluation of a new, rugged bCPAP system that can be made in small volume for a cost-of-goods of approximately $350. Moreover, because of its simple design--consumer-grade pumps, medical tubing, and regulators--it requires only the simple replacement of a <$1 diaphragm approximately every 2 years for maintenance. The low-cost bCPAP device delivers pressure and flow equivalent to those of a reference bCPAP system used in the developed world. We describe the initial clinical cases of a child with bronchiolitis and a neonate with respiratory distress who were treated successfully with the new bCPAP device.
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Este ensino clínico permitiu-nos prestar cuidados de enfermagem especializados a 16 homens com esquizofrenia em processo de reabilitação psicossocial. Na sua maioria são: adultos, solteiros, da região sul de Portugal, com uma média de 9 anos de escolaridade, com história de consumo de substâncias (álcool, tabaco, haxixe, cocaína, heroína e anfetaminas), institucionalizados na Casa de Saúde do Telhal (CST) há mais de 11 anos. Todos apresentam diagnósticos de enfermagem das várias dimensões do adoecer, com exceção da dimensão comportamental excitatória, sendo os de maior prevalência: “Conhecimento sobre Processo de doença/Cuidados na doença/Tratamento, Não Demonstrado”; Cognição, Comprometida”; “Processo Social, Alterado”; “Autoestima, Diminuída”. Foram desenvolvidos 4 programas de intervenção: consulta de enfermagem de saúde mental e psiquiatria (CESMP); atelier de estimulação cognitiva (AEC); programa de desenvolvimento de competência intrapessoais, interpessoais e profissionais (PDCIIP); programa de psicoeducação (SABER+). A satisfação global com os programas foi superior a 7 (numa escala de 1 a 10) e os resultados que foram percebidos pela maioria dos reabilitandos situaram-se acima das suas expectativas iniciais. De uma forma geral, todos registaram ganhos: no desempenho cognitivo (em particular os que beneficiaram do AEC); na adaptação psicossocial – nomeadamente ao nível do insight; os reabilitandos que beneficiaram do programa SABER+ melhoraram ainda os comportamentos demonstrados de aceitação do estado de saúde; no bem-estar psicológico – nomeadamente ao nível da autoestima (sobretudo os que beneficiaram da CESMP e/ou do PDCIIP), dos afetos positivos e dos comportamentos de motivação; nos vários domínios da qualidade de vida (QdV) medidos pelo WHOQOL-Bref em particular o domínio ambiental; todos elevaram o seu nível de conhecimentos nos 3 eixos em que que se estruturou o programa de psicoeducação (processo da doença, cuidados na doença, tratamento da doença); na adesão à medicação, sobretudo os que integraram o programa de psicoeducação, contudo todos tendem a necessitar de ajuda parcial para conseguir demonstrar conhecimento no cumprimento do esquema terapêutico e estão envolvidos em treinos supervisionados de preparação e autoadministração; ABSTRACT: This clinical training allowed us to provide skilled nursing care to 16 men with schizophrenia in a psychosocial rehabilitation setting. Most of these individuals are: adults, singles, from the southern region of Portugal, with an average of 9 years of schooling, with a history of substance abuse (alcohol, tobacco, cannabis, cocaine, heroin and amphetamines), institutionalized in Casa de Saúde do Telhal (CST) for over 11 years. We find nursing diagnoses from all of the disease dimensions with the exception of excitatory behavioral dimension, being the most prevalent: "knowledge about disease process / care / treatment, not stated"; cognition, impaired", "social process, impaired”, “self-esteem, decreased". We developed 4 intervention programs: psychiatry and mental health nursing consultation (CESMP); atelier of cognitive stimulation (AEC); intrapersonal, interpersonal and professional competences training (PDCIIP); psychoeducation (SABER+). The overall satisfaction with the programs was above 7 (on a scale of 1 to 10) and the results noticed by most patients were above their initial expectations. All registered nursing results were: in cognitive performance (particularly those who benefited from the AEC); in psychosocial adaptation - especially in terms of insight; patients who benefited from the SABER+ program demonstrated improved further acceptance of their health condition, psychological well-being, particularly in terms of self-esteem (especially those who benefited from the CESMP and/or the PDCIIP), positive affects and motivation; in the different domains of quality of life (QoL) measured by WHOQOL-Bref in particular the environmental domain; every patients raised their level of knowledge in the 3 axes in which the psychoeducational program (SABER+) was structured (disease process, care and treatment); in medication adherence, especially those who benefited of the psychoeducational program, however all the patients tend to need partial help to demonstrate knowledge in meeting the therapeutic regimen and are involved in supervised training programs for preparation and self administration.
Resumo:
Acute liver failure is rarely secondary to lymphoma or leukaemia and it is extremely uncommon as the initial presentation of malignancy. We report a case of a young adult patient with severe acute liver failure referred for liver transplant, in which a Burkitt acute lymphoblastic leukaemia was diagnosed by bone marrow examination. A complete recovery and long remission were obtained with chemotherapy.