999 resultados para Folow-up


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PURPOSE: To model the possible impact of using average-power intraocular lenses (IOLs) and evaluate the postoperative refractive error in patients having cataract surgery in rural China.SETTING: Rural Guangdong, China.METHODS: Patients having cataract surgery by local surgeons were examined and visual function was assessed 10 to 14 months after surgery. Subjective refraction at near and distance was performed bilaterally by an ophthalmologist. Patients had a target refraction of -0.50 diopter (D) based on ocular biometry.RESULTS: Of the 313 eligible patients, 242 (77%) could be contacted and 176 (74% of contacted patients, 56% overall) were examined. Examined patients had a mean age of 69.4 +/- 10.5 years. Of the 211 operated eyes, 73.2% were within +/-1.0 D of the target refraction after surgery. The best presenting distance vision was in patients within +/-1.0 D of plano and the best presenting near vision, in those with mild myopia (<-1.0 D to > or =2.0 D) (P= .005). However, patients with hyperopia (>+1.0 D) reported significantly better adjusted visual function than those with emmetropia or myopia (<-1.0 D). When the predicted use of an average-power IOL (median +21.5 D) was modeled, predicted visual acuity was significantly reduced (P= .001); however, predicted visual function was not significantly altered (P>.3).CONCLUSIONS: Accurate selection of postoperative refractive error was achieved by local surgeons in this rural area. Based on visual function results, aiming for mild postoperative myopia may not be suitable in this setting. Implanting average-power IOLs significantly reduced postoperative presenting vision, but not visual function.

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AIM: To study patient sources of knowledge about cataract surgical services, and strategies for financing surgery in rural China. DESIGN: Cross-sectional case series. METHODS: Patients undergoing cataract surgery by local surgeons in a government, village-level facility in Sanrao, Guangdong between 8 August and 31 December 2005 were examined and had standardised interviews an average of 12 months after surgery. RESULTS: Of 313 eligible patients, 239 (76%) completed the questionnaire. Subjects had a mean (SD) age of 69.9 (10.2) years, 36.4% (87/239) were male, and 87.0% (208/239) had been blind (presenting visual acuity < or = 6/60) before surgery. Word-of-mouth advertising was particularly important: 198 (85.0%) of the subjects knew a person who had undergone cataract surgery, of whom 191 (96.5%) had had cataract surgery at Sanrao itself. Over 70% of subjects (166/239) watched TV daily, whereas 80.0% (188/239) "never" read the newspaper. Nearly two-thirds of suggestions from participants (n = 211, 59.6%) favoured either TV advertisements or word-of-mouth to publicise the programme. While the son or daughter had paid for surgery in over 70% of cases (164/233), the patient's having paid without help was the sole predictor of undergoing second-eye surgery (OR 2.27 (95% CI 1.01 to 5.0, p = 0.04)). DISCUSSION: Strategies to increase uptake of cataract surgery in rural China may benefit from enhancing word-of-mouth advertising (such as with pseudophakic motivators), using television advertising where affordable, and micro-credit or other programmes to enable patients to pay their own fees, thus increasing uptake of second-eye surgery.

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AIM: To study the effect of posterior capsular opacification (PCO) on vision and visual function in patients undergoing cataract surgery in rural China, and to compare this with the effect of refractive error. METHODS: Patients undergoing cataract surgery in at least one eye by local surgeons in a rural setting between 8 August and 31 December 2005 were examined with slit lamp grading of PCO 10-14 months after surgery. Subjects with any PCO associated with best-corrected visual acuity of 6/7.5 or worse, or with grade 2+ or worse PCO without visual decrement, were offered YAG laser capsulotomy. Vision and self-reported visual function were assessed, and various demographic and clinical factors potentially associated with PCO were recorded. RESULTS: Of 313 patients operated on within the study window, 239 (76%) could be contacted by telephone; study examinations were performed on 176 (74%). Examined subjects had a mean (SD) age of 69.4 (10.5) years, 116 (67%) were female, and 149 (86%) had been blind (presenting visual acuity < or = 6/60) in the operated eye before surgery. PCO of grade 1 or above was present in 34 of 204 operated eyes (16.7%). Those with PCO had significantly worse presenting vision (p = 0.007) but not visual function (p>0.3) than those without PCO. Women had a significantly higher prevalence of PCO (20.9%) than did men (8.6%, p<0.05). Of 19 eyes undergoing capsulotomy with best-corrected visual acuity measured the next day, 13 (68%) improved by one or more lines, and seven (37%) improved by two or more lines. Despite a higher uptake of capsulotomy (95%) as opposed to refraction (35%) in this cohort, the yield in terms of eyes with poor presenting visual acuity (< 6/18) that could be improved was higher for refraction (26% = 9/35) than for capsulotomy (9% = 3/35). CONCLUSION: The prevalence of PCO and impact on vision and visual function in this cohort was modest 1 year after surgery. However, PCO prevalence increases with time. Follow-up of this cohort is underway to determine the effectiveness of this early intervention in identifying and treating subjects who will eventually experience clinically significant PCO.

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PURPOSE:

To evaluate reasons for non-compliance with post-cataract surgical follow-up in rural China, and assess the impact of incentives on improving compliance.

METHODS:

Patients having undergone cataract surgery more than 3 months previously at cataract surgery training hospitals in Guangdong were invited by telephone and advertisements to a hospital-based study examination, with compensation for travel costs (US$7). Information on prior post-surgical follow up was collected by questionnaire at the hospital or by telephone. Logistic regression was used to assess predictors of post-operative attendance with or without compensation.

RESULTS:

Among 518 eligible patients, 426 (82.2%) underwent interviews and 342 (66.0%) attended the compensated study examination. Ninety nine participants (23.2%) reported previously returning for uncompensated follow-up ≥ 3 months post-operatively, and 225 (52.8%) had returned for any prior post-operative examination. Uncompensated follow-up at ≥ 3 months was associated with higher income (P = 0.037), and recalling instruction by a doctor to follow-up (P = 0.001), while age, gender, travel cost, and post-operative satisfaction and vision were not associated. Younger (P = 0.002) patients and those reporting being instructed to follow up (P = 0.008) were more likely to return for the compensated research examination. Among all interviewed subjects, only 170 (39.9%) reported knowing they were to return to hospital.

CONCLUSIONS:

Modest compensation, advertisements and telephone contact can increase medium-term follow-up rates after cataract surgery by three-fold. Better communication of specific targets for follow-up may improve follow-up compliance.

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We have collected initial evidence that tidal interaction between a late-type star and its close-in, massive planet can lead to a spin-up of the host star. We propose to explore this further by studying a small sample of proper motion pairs in which one of the stars is orbited by a Hot Jupiter. We will determine if the activity-estimated age appears to be strongly different for the two stars, which would indicate a tidal spin up of the Hot Jupiter host star. We propose to observe 4 such systems with Chandra/ACIS-S, and to perform a similar observation of one additional system with large angular separation using XMM-Newton/EPIC. The total proposed exposure times are 141 ks (Chandra) and 38 ks (XMM).

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We have collected initial evidence that tidal interaction between a late-type star and its close-in, massive planet can lead to a spin-up of the host star. We propose to explore this further by studying a small sample of proper motion pairs in which one of the stars is orbited a Hot Jupiter. We will determine if the gyrochronal age is different for the two stars, which would indicate a tidal spin up of the planet host star. We propose to observe 3 such systems with XMM, and to perform similar Chandra observations of 3 more systems with angular separations

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This paper presents an approach to develop an intelligent digital mock-up (DMU) through integration of design and manufacturing disciplines to enable a better understanding of assembly related issues during design evolution. The intelligent DMU will contain tolerance information related to manufacturing capabilities so it can be used as a source for assembly simulations of realistic models to support the manufacturing decision making process within the design domain related to tolerance build ups. A literature review of the contributing research areas is presented, from which identification of the need for an intelligent DMU has been developed. The proposed methodology including the applications of cellular modelling and potential features of the intelligent DMU are presented and explained. Finally a conclusion examines the work to date and the future work to achieve an intelligent DMU.

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In this research we aimed to find out what types of risk (if any) affected young people and children growing up in places of high religious segregation or what we normally call interface communities. This is important as we know that risk and experiences of harm and violence can have negative impacts upon development, emotional well-being and future prospects. It is important to understand what types of risk affect young people and children so as we can respond to these in terms of aiding better personal and community development with regard to health, work, education and wider opportunities.

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Background: Prospective investigations of the association between impaired orthostatic blood pressure (BP) regulation and cognitive decline in older adults are limited, and findings to-date have been mixed. The aim of this study was to determine whether impaired recovery of orthostatic BP was associated with change in cognitive function over a 2-year period, in a population based sample of community dwelling older adults. 

Methods: Data from the first two waves of the Irish Longitudinal Study on Ageing were analysed. Orthostatic BP was measured during a lying to standing orthostatic stress protocol at wave 1 using beat-to-beat digital plethysmography, and impaired recovery of BP at 40 s post stand was investigated. Cognitive function was assessed at wave 1 and wave 2 (2 years later) using the Mini-Mental State Exam (MMSE), verbal fluency and word recall tasks. 

Results: After adjustment for measured, potential confounders, and multiple imputation for missing data, the change in the number of errors between waves on the MMSE was 10 % higher [IRR (95 % CI) = 1.10 (0.96, 1.26)] in those with impaired recovery at 40 s. However, this was not statistically significant (p = 0.17). Impaired BP recovery was not associated with change in performance on any of the other cognitive measures. 

Conclusions: There was no clear evidence for an association between impaired recovery of orthostatic BP and change in cognition over a 2-year period in this nationally representative cohort of older adults. Longer follow-up and more detailed cognitive testing would be advantageous to further investigate the relationship between orthostatic BP and cognitive decline.

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Purpose: To evaluate preoperative characteristics and follow-up in rural China after trabeculectomy, the primary treatment for glaucoma there. Methods: Patients undergoing trabeculectomy at 14 rural hospitals in Guangdong and Guangxi Provinces and their doctors completed questionnaires concerning clinical and sociodemographic information, transportation, and knowledge and attitudes about glaucoma. Follow-up after surgery was assessed as cumulative score (1 week: 10 points, 2 weeks: 7 points, 1 month: 5 points). Results Among 212 eligible patients, mean preoperative presenting acuity in the operative eye was 6/120, with 61.3% (n=130) blind (≤6/60). Follow-up rates were 60.8% (129/212), 75.9% (161/212) and 26.9% (57/212) at 1 week, 2 weeks and 1 month, respectively. Patient predictors of poor follow-up included elementary education or less (OR=0.37, 95% CI 0.20 to 0.70, p=0.002), believing follow-up was not important (OR=0.62, 95% CI 0.41 to 0.94, p=0.02), lack of an accompanying person (OR=0.14, 95% CI 0.07 to 0.29, p<0.001), family annual income <US$800 (OR=0.28, 95% CI 0.11 to 0.72, p=0.008) and not requiring removal of scleral flap sutures postoperatively (OR=0.11, 95% CI 0.06 to 0.22, p<0.001). Age, sex, employment, travel distance/time/costs, patient preoperative clinical factors and physician factors were unassociated with follow-up. Conclusions: Follow-up after 2 weeks was inadequate to provide optimal clinical care, and surgery is being applied too late to avoid blindness in the majority of patients. Earlier surgery, support for return visits and better explanations of the importance of follow-up are needed. Directing all patients to return for possible scleral flap suture removal may be a valid strategy to improve follow-up.

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Introduction
Standard treatment for neovascular age-related macular degeneration (nAMD) is intravitreal injections of anti-VEGF drugs. Following multiple injections, nAMD lesions often become quiescent but there is a high risk of reactivation, and regular review by hospital ophthalmologists is the norm. The present trial examines the feasibility of community optometrists making lesion reactivation decisions.

Methods
The Effectiveness of Community vs Hospital Eye Service (ECHoES) trial is a virtual trial; lesion reactivation decisions were made about vignettes that comprised clinical data, colour fundus photographs, and optical coherence tomograms displayed on a web-based platform. Participants were either hospital ophthalmologists or community optometrists. All participants were provided with webinar training on the disease, its management, and assessment of the retinal imaging outputs. In a balanced design, 96 participants each assessed 42 vignettes; a total of 288 vignettes were assessed seven times by each professional group.The primary outcome is a participant's judgement of lesion reactivation compared with a reference standard. Secondary outcomes are the frequency of sight threatening errors; judgements about specific lesion components; participant-rated confidence in their decisions about the primary outcome; cost effectiveness of follow-up by optometrists rather than ophthalmologists.

Discussion
This trial addresses an important question for the NHS, namely whether, with appropriate training, community optometrists can make retreatment decisions for patients with nAMD to the same standard as hospital ophthalmologists. The trial employed a novel approach as participation was entirely through a web-based application; the trial required very few resources compared with those that would have been needed for a conventional randomised controlled clinical trial.

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As propriedades funcionais dos materiais ferroeléctricos tais como a polarização reversível, piroelectricidade, piezoelectricidade, elevada actividade óptica não linear e comportamento dieléctrico não linear são fundamentais para a sua aplicação em sensores, microactuadores, detectores de infravermelhos, filtros de fase de microondas e memórias não-voláteis. Nos últimos anos, motivado pelas necessidades industriais de redução do tamanho dos dispositivos microelectrónicos, aumentando a eficiência volumétrica, tem sido feito um grande esforço ao nível da investigação para desenvolver estruturas ferroeléctricas à escala micro- e nano- métrica. É sabido que a redução de tamanho em materiais ferroeléctricos afecta significamente as suas propriedades. Neste sentido e considerando que foi previsto teoreticamente por cálculos ab initio que estruturas do tipo nanocilindros e nanodiscos apresentariam um novo tipo de ordem ferroeléctrica e, na expectativa de alcançar conhecimento para o desenvolvimento de uma nova geração de dispositivos microelectróncos, existe um grande interesse em desenvolver métodos de fabrico de nanoestruturas ferroeléctricas unidimensionais (1D) tais como nanocilindros e nanotubos. As estratégias de fabrico de nanoestruturas 1D até agora descritas na literatura indicam claramente as dificuldades inerentes à sua preparação. Existem duas grandes vias de síntese destas nanoestruturas: i) o método “topdown” que consiste na redução de tamanho de um dado material até à obtenção duma estrutura 1D; e ii) o método “bottom-up” em que átomos, iões e moléculas são agrupados para formar um material 1D. O método “top down” envolve em geral técnicas de desgaste, como o uso do feixe de electrões, que apesar de permitirem elevada precisão no posicionamento e no controlo do tamanho, falham em termos de resolução, exigem muito tempo e causam facilmente defeitos que deterioram as propriedades físicas destes materiais. Na metodologia “bottom up” a utilização de moléculas ou estruturas “molde” tem sido a mais explorada. As estructuras 1D podem também ser preparadas sem recorrer a “moldes”. Neste caso a agregação orientada é promovida pelo recurso a aditivos que controlam o crescimento dos cristais em direcções preferenciais. Neste contexto, neste trabalho utilizaram-se duas estratégias “bottom up” de baixo custo para a preparação de nanopartículas de titanato de bário (BaTiO3) com morfologia controlada: 1) síntese química (em solução e em fase vapor) com utilização de nanotubos de titanato TiNTs) como “moldes” e precursores de titânio 2) síntese química em solução com presença de aditivos. Os nanotubos de titanato de sódio foram preparados por síntese hidrotermal. Como existiam muitas dúvidas acerca da natureza estrutural e do mecanismo de formação dos NTs, a parte inicial do trabalho foi dedicada à realização de um estudo sistemático dos parâmetros intervenientes na síntese e à caracterização da sua estrutura e microestrutura. Foi demonstrado que os NTs têm a fórmula geral A2Ti2O5 (A = H+ or Na+), e não TiO2 (anátase) com defendido por vários autores na literatura, e podem ser preparados por método hidrotermal em meio fortemente alcalino usando como fonte de titânio TiO2 comercial na forma de anátase ou rútilo. A menor reactividade do rútilo exige temperaturas de síntese superiores ou tempos de reacção mais longos. A forma tubular resulta do tratamento hidrotermal e não de processos de lavagem e neutralização subsequentes. Se os NTs forem tratados após a síntese hidrotérmica em água a 200 ºC, transformam-se em nanocilindros. Uma das partes principais desta tese consistiu na investigação do papel dos NTs de titanato no crescimento anisotrópico de BaTiO3. O potencial funcionamento dos NTs como “moldes” para além de precursores foi testado em reacção com hidróxido de bário em síntese em solução e por reacção com um precursor orgânico de bário em fase vapor. Tendo por base os estudos cinéticos realizados, bem como as alterações estruturais e morfológicas das amostras, é possível concluir que a formação do BaTiO3 a partir de NTs de titanato de sódio, ocorre por dois mecanismos dependendo da temperatura e tempo de reacção. Assim, a baixa temperatura e curto tempo de reacção verifica-se que se formam partículas dendríticas de BaTiO3 cuja superfície é bastante irregular (“wild”) e que apresentam estrutura pseudo-cúbica. Estas partículas formam-se por reacção topotáctica na fronteira dos nanotubos de titanato de sódio. A temperaturas mais altas e/ou reacções mais longas, a reacção é controlada por um mecanismo de dissolução e precipitação com formação de dendrites de BaTiO3 tetragonais com superfície mais regular (“seaweed”). A microscopia de força piezoeléctrica mostrou que as dendrites “seaweeds“ possuem actividade piezoeléctrica superior à das dendrites “wild”, o que confirma o papel desempenhado pela estrutura e pela concentração de defeitos na rede na coerência e ordem ferroeléctrica de nanoestruturas. Os nossos resultados confirmam que os NTs de titanato não actuam facilmente como “moldes” na síntese em solução de BaTiO3 já que a velocidade de dissolução dos NTs em condições alcalinas é superior à velocidade de formação do BaTiO3. Assumindo que a velocidade de reacção dos NTs com o precursor de bário é superior em fase vapor, efectuou-se a deposição de um precursor orgânico de bário por deposição química de vapor sobre um filme de NTs de titnato de sódio depositados por deposição electroforética. Estudou-se a estabilidade dos NTs nas diferentes condições do reactor. Quando os NTs são tratados a temperaturas superiores a 700 ºC, ocorre a transformação dos NTs em nanocilindros de anatase por um mecanismo de agregação orientada. Quando se faz a deposição do precursor de bário, seguida de calcinação a 700 ºC em atmosfera oxidante de O2, verifica-se que a superficie dos NTs fica coberta com nanocristais de BaTiO3 independentemente da concentração de bário. O papel dos NTs de titanato no crescimento anisotrópico de BaTiO3 em fase vapor é assim descrito pela primeira vez. Em relação à metodologias de crescimento de partículas na ausência de “moldes” mas com aditivos fez-se um estudo sistemático utilizando 5 aditivos de natureza differente. As diferenças entre aditivos foram sistematizadas tendo em conta as diferenças estruturais e morfológicas verificadas. Está provado que os aditivos podem funcionar como modificadores de crescimento cristalino por alteração do seu padrão de crescimento ou por alteração da cinética de crescimento das faces cristalográficas do cristal. Entre os aditivos testados verificou-se que o ácido poliacrilíco adsorve em faces específicas do BaTiO3 alterando a cinética de crescimento e induzindo a agregação orientada das partículas. O polivinilpirrolidona, o docecilsulfato de sódio e hidroxipropilmetilcelulose actuam mais como inibidores de crescimento do que como modificadores do tipo de crescimento. A D-frutose aumenta a energia de activação da etapa de nucleação não ocorrendo formação de BaTiO3 para as mesmas condições dos outros aditivos. Esta tese clarifica o papel dos NTs de titanato de sódio enquanto precursores e “moldes” no crescimento anisotrópico de BaTiO3 em solução e em fase vapor. É feita também a abordagem do controlo morfológico do BaTiO3 através do uso de aditivos. As estratégias de preparação de BaTiO3 propostas são de baixo custo, reprodutíveis e fáceis de efectuar. Os resultados contribuem para uma melhor compreensão da relação tamanho – morfologia – propriedade em materiais ferroeléctricos nanométricos com vista à sua potencial aplicação.

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The purpose of this text is to analyse two recently been published pop-up books aimed at children, by Anouck Boisrobert e Louis Rigaud, Popville (2009) and Dans la forêt du paresseux [Wake up, Sloth!, En el bosque del perezoso] (first published in 2009 and 2012, accompanied with texts by Joy Sorman and Sophie Strady, respectively). These books were published originally in France by Hélium Editions, but they can now be found in several western countries and in many languages (Catalan, French, Dutch, English, German, Italian, Portuguese and Spanish, at least). The objective is to analyse their verbal text and their visual aspects produced by a sophisticated paper engineered to question how they achieve what seems to be one of their goals, the promotion of the readers' ecoliteracy (Orr, 1992) by his involvement in the reading process. This issue seems to be one of the main trends on children's literature in western societies nowadays, transcending the traditional and almost omnipresent role of scenario that nature plays in many children's narratives.