845 resultados para Mann Whitney U-test


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O objetivo desse trabalho foi avaliar a biocompatibilidade de um material a base de guta-percha autoadesiva (Bio-Gutta) em tecido subcutâneo de camundongos. A guta-percha convencional foi utilizada como referência para comparação. Para isso, foram utilizados 30 camundongos, os quais foram distribuídos aleatoriamente em dois grupos (Bio-Gutta e guta-percha convencional). Os materiais avaliados foram implantados na região dorsal dos camundongos. Após 7, 21 e 63 dias, os animais foram sacrificados e 5 amostras por grupo por tempo experimental foram obtidas. As amostras histológicas foram seccionadas em 5 m de espessura e coradas convencionalmente com hematoxilina e eosina. Um escore de I-IV foi utilizado para graduar a reação inflamatória. O teste U de Mann-Whitney com correção de Bonferroni foi utilizado para análise estatística (p < 0,05). Os resultados mostraram que, após 7 dias, a Bio-Gutta induziu uma reação tecidual de leve a moderada (II) e a guta-percha convencional apresentou uma resposta inflamatória de moderada a intensa (III). Após 21 dias, a Bio-Gutta induziu uma leve reação tecidual (I), enquanto que a guta-percha convencional ainda apresentava uma resposta inflamatória moderada (III). Uma reação tecidual de leve a ausente (I) foi observada na Bio-Gutta após 63 dias, ao passo que na guta-percha convencional observou-se uma resposta inflamatória de leve a moderada (II). Houve diferença significativa na mediana do grau de inflamação entre os grupos em cada tempo experimental (p = 0,005, aos 7 dias; p = 0,011, aos 21 dias; e p = 0,003, aos 63 dias). Concluiu-se então que a Bio-Gutta foi mais biocompatível que a guta-percha convencional em tecido subcutâneo de camundongos apresentando uma boa resposta tecidual.

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A poluição sonora é um grave problema nos oceanos devido à eficiência de propagação do som na água e à importância da comunicação acústica para os organismos marinhos. Delfinídeos utilizam o som para comunicação, coordenação de grupo, percepção do hábitat e busca por alimentos, já tendo sido demonstrado que podem alterar suas vocalizações em função do aumento do ruído subaquático. O presente estudo realizou uma comparação dos assobios do boto-cinza Sotalia guianensis em dois ambientes acústicos distintos, um silencioso e um ruidoso, dentro da Baía de Guanabara, Rio de Janeiro, Brasil. Também foram realizadas investigadas as relações dos parâmetros acústicos dos assobios de S. guianensis com os valores de pressão sonora do ruído subaquático. O sistema de gravação foi totalmente calibrado e consistiu de um gravador digital Marantz PMD670 com taxa de amostragem de 96 kHz e um hidrofone HTI-96MIN (5 Hz 30 kHz, sensibilidade média de -170,5 dB re 1 Pa). As gravações realizadas dos assobios e do ruído subaquático ocorreram simultaneamente em duas regiões da baía: a APA de Guapimirim e o Canal central. Durante o período de amostragem os grupos de S. guianensis foram observados em três estados comportamentais: alimentação, deslocamento e socialização; foram anotadas também informações quanto a tamanho e composição de grupo. A análise dos assobios foi realizada no software Raven 1.4 e 10 parâmetros acústicos foram extraídos. Também foi calculada a razão de emissão de assobios. A análise de ruído subaquático foi realizada no software Adobe Audition 1.5, onde foram extraídos valores de pressão sonora do ruído 300ms imediatamente antes de cada assobio analisado, sendo utilizados para análise estatística os maiores valores de pressão sonora dentro de sete intervalos de frequência. Um Teste U de Mann-Whitney foi aplicado para comparar os parâmetros acústicos dos assobios e os valores de pressão sonora das duas regiões amostradas. Esta comparação foi feita para cada estado comportamental observado durante a coleta. Posteriormente foi realizado um teste de correlações de Spearman para investigar a relação entre os parâmetros acústicos e os valores de pressão sonora. Este teste também foi feito separadamente para cada estado comportamental. No comportamento de alimentação foi encontrada diferença na duração, na frequência central e em todos os valores de pressão sonora. Durante o comportamento de socialização foi encontrada diferença na duração e em todos os valores de pressão sonora. Durante o comportamento de alimentação foi encontrada relação entre cinco parâmetros acústicos, a taxa de vocalização e a pressão sonora. Durante o comportamento de socialização foi encontrada relação entre a duração e a pressão sonora. S. guianensis alterou seu comportamento acústico em situações ruidosas, diminuindo a duração e aumentando a taxa de vocalização. Na Baía de Guanabara esta espécie está exposta diariamente a poluição sonora, sendo a APA de Guapimirim o ambiente acústico menos perturbado a que S. guianensis tem acesso.

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A total of 91 species under 44 genera were identified among the phytoplankton community during the course of one year's investigation between May 1982 and April 1983. Bacillariophyta was the most dominant group with 72 specie, Chlorophyta 11 spp, Cyanophyta 6 spp and Pyrrophyta was represented by 2 species. The yearly percentage composition of 4 groups of phytoplankton in order of abundance were Bacillariophyta 50.77%, Cyanophyta 47.70%, Chlorophyta 1.5% and Pyrrophyta 0.02%. The highest densities of phytoplankton were recorded in monsoon months (June-July) with a peak in July (31550 cells/l) and the minimum in February (770 cells/1). Higher concentration of phytoplankton was recorded at station 2, nearer to the Chakaria Sundarbans (mangroves), but abundance of phytoplankton showed no significant difference in the two stations (Mann Whitney U test, P=0.64, Z=-0.642, U=64). Phytoplankton population in this area were positively correlated with rainfall (r=0.655, P=<0.5, df.22) and water temperature (r=0.523, P=<0.05). Skeletonema costatum was the dominant member of phytoplankton and occupied 35.23% of the annual population and occurred throughout the period of study except in September and January. Its abundance was recorded during the monsoon months (April- July) with a maximum density (24185 cells/l) in July. No significant correlation was found between abundance of S. costatum and the hydro-meteorological parameters recorded in the Chakaria mangrove area.

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Processes of enrichment, concentration and retention are thought to be important for the successful recruitment of small pelagic fish in upwelling areas, but are difficult to measure. In this study, a novel approach is used to examine the role of spatio-temporal oceanographic variability on recruitment success of the Northern Benguela sardine Sardinops sagax. This approach applies a neural network pattern recognition technique, called a self-organising map (SOM), to a seven-year time series of satellite-derived sea level data. The Northern Benguela is characterised by quasi-perennial upwelling of cold, nutrient-rich water and is influenced by intrusions of warm, nutrient-poor Angola Current water from the north. In this paper, these processes are categorised in terms of their influence on recruitment success through the key ocean triad mechanisms of enrichment, concentration and retention. Moderate upwelling is seen as favourable for recruitment, whereas strong upwelling, weak upwelling and Angola Current intrusion appear detrimental to recruitment success. The SOM was used to identify characteristic patterns from sea level difference data and these were interpreted with the aid of sea surface temperature data. We found that the major oceanographic processes of upwelling and Angola Current intrusion dominated these patterns, allowing them to be partitioned into those representing recruitment favourable conditions and those representing adverse conditions for recruitment. A marginally significant relationship was found between the index of sardine recruitment and the frequency of recruitment favourable conditions (r super(2) = 0.61, p = 0.068, n = 6). Because larvae are vulnerable to environmental influences for a period of at least 50 days after spawning, the SOM was then used to identify windows of persistent favourable conditions lasting longer than 50 days, termed recruitment favourable periods (RFPs). The occurrence of RFPs was compared with back-calculated spawning dates for each cohort. Finally, a comparison of RFPs with the time of spawning and the index of recruitment showed that in years where there were 50 or more days of favourable conditions following spawning, good recruitment followed (Mann-Whitney U-test: p = 0.064, n = 6). These results show the value of the SOM technique for describing spatio-temporal variability in oceanographic processes. Variability in these processes appears to be an important factor influencing recruitment in the Northern Benguela sardine, although the available data time series is currently too short to be conclusive. Nonetheless, the analysis of satellite data, using a neural network pattern-recognition approach, provides a useful framework for investigating fisheries recruitment problems.

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Purpose: Positron emission tomography (PET), in addition to computed tomography (CT), has an effect in target volume definition for radical radiotherapy (RT) for non–small-cell lung cancer (NSCLC). In previously PET-CT staged patients with NSCLC, we assessed the effect of using an additional planning PET-CT scan for gross tumor volume (GTV) definition. Methods and Materials: A total of 28 patients with Stage IA-IIIB NSCLC were enrolled. All patients had undergone staging PET-CT to ensure suitability for radical RT. Of the 28 patients, 14 received induction chemotherapy. In place of a RT planning CT scan, patients underwent scanning on a PET-CT scanner. In a virtual planning study, four oncologists independently delineated the GTVon the CT scan alone and then on the PET-CTscan. Intraobserver and interobserver variability were assessed using the concordance index (CI), and the results were compared using the Wilcoxon signed ranks test. Results: PET-CT improved the CI between observers when defining the GTVusing the PET-CT images compared with using CTalone for matched cases (median CI, 0.57 for CTand 0.64 for PET-CT, p = .032). The median of the mean percentage of volume change from GTVCT to GTVFUSED was 5.21% for the induction chemotherapy group and 18.88% for the RT-alone group. Using the Mann-Whitney U test, this was significantly different (p = .001). Conclusion: PET-CT RT planning scan, in addition to a staging PET-CT scan, reduces interobserver variability in GTV definition for NSCLC. The GTV size with PET-CT compared with CT in the RT-alone group increased and was reduced in the induction chemotherapy group.

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Few markers distinguish between different dementia types. As dementia affects many body systems outside the central nervous system, we investigated gastrointestinal regulatory peptides as possible disease markers in Alzheimer's Disease (AD) and vascular dementia (VaD). Subjects with mild-to-moderate dementia were diagnosed as probable AD and VaD according to defined criteria. Gastrointestinal peptides were stimulated using a standardized meal test, administered after an overnight fast to 58 dementia patients (40 AD, 18 VaD) and 47 controls matched for age and sex. Blood samples were taken at designated time intervals, and basal and stimulated plasma concentrations of eleven peptides were determined by radio-immunoassay. Results were analysed using the Kruskal-Wallis one-way analysis of variance; the Mann-Whitney U test was used in post hoc analysis where appropriate. There were significant differences in somatostatin levels but in none of the other peptides. Basal somatostatin was significantly increased in VaD compared to controls (p

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Background: The transition from school to university can be challenging and there is increasing concern among academics that students are inadequately prepared for entry to university courses.Aims: To investigate students’ views on transition from school to university education.Method: A focus group was conducted with first-year students and analysed using thematic analysis. Students were invited to participate in an electronic questionnaire; responses were analysed via SPSS for Windows. The MannWhitney U test was utilised with p<0.05 set as significant.Results: A response rate of 60% (88/147) was obtained for the questionnaire. Differences included staff-student interactions, learning methods, examination preparation and feedback provision. Many (85%) agreed that the main emphasis in school was on examination preparation; 29.6% considered this to be the case at university (z=-8.315; p<0.05). Most students (95.4%) considered the feedback they received at school helped improve performance; this decreased to 50% when asked about feedback at university (z=-8.326; p<0.05).Conclusion: Students appear to be insufficiently prepared for the demands of higher education. They desire various aspects of their university educational experience to be more akin to that of school, including: a greater level of individual attention, increased access to teaching staff, and further clarification and transparency about the standard required to pass exams. Further work can now be done by academic staff to aid the transition and improve the learning experience.

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High Fidelity Simulation or Human Patient Simulation is an educational strategy embedded within nursing curricula throughout many healthcare educational institutions. This paper reports on an evaluative study that investigated the views of a group of Year 2 undergraduate nursing students from the mental health and the learning disability fields of nursing (n = 75) in relation to simulation as a teaching pedagogy. The study took place in the simulation suite within a School of Nursing and Midwifery in the UK. Two patient scenarios were used for the session and participants completed a 22-item questionnaire consisting of three biographical information questions and a 19-item Likert scale. Descriptive statistics were employed to illustrate the data and non-parametric testing (Mann-Whitney U test) was employed to test a number of hypotheses. Overall students were positive about the introduction of patient scenarios using the human patient simulator into the undergraduate nursing curriculum. This study used a small, convenience sample in one institution and therefore the results obtained cannot be generalised to nursing education before further research can be conducted with larger samples and a mixed-method research approach. However these results provide encouraging evidence to support the use of simulation within the mental health and the learning disability fields of nursing, and the development and implementation of further simulations to complement the students’ practicum.

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Objectives: The primary aim of this study was to investigate partially dentate elders’ willingness-to-pay (WTP) for two different tooth replacement strategies: using Removable Partial Dentures (RPDs) and, functionally orientated treatment (SDA). The secondary aim was to measure the same patient group’s WTP for dental implants. Methods: Patients who had completed a previous RCT comparing two tooth replacement strategies (RPDs and SDA) were recruited. 59 patients were asked to indicate their WTP for treatment to replace missing teeth in a number of hypothetical scenarios using the payment card method of contingency evaluation coupled to different costs. Data were collected on patients’ social class, longest held occupation, income levels and social circumstances. Results: The median age for the patient sample was 72.0 years (IQR: 71-75 years). Patients who had previously been provided with RPDs indicated that their WTP for this treatment strategy was significantly higher than those patients who had received SDA treatment (Mann-Whitney U Test: p<0.001). This group were also WTP a higher price for SDA treatment than those patients who had previously been treated according to this modality (Mann-Whitney U Test: p=0.005). The results indicated that patients’ age was not correlated with WTP but both social class and current income levels were significantly correlated (Spearman’s rank correlation: p<0.05). Patients in both treatment groups exhibited llittle WTP for dental implant treatment with a median price recorded which was lower than either RPD or SDA treatment. Conclusions: Amongst this patient cohort previous treatment experience had a strong influence on WTP as did social class and current income levels. The patients’ WTP indicated that they did not value dental implants over simpler forms of tooth replacement such as RPDs or a SDA approach.

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Objectives: The primary aim of this study was to investigate partially dentate elders’ willingness-to-pay (WTP) for two different tooth replacement strategies: using Removable Partial Dentures (RPDs) and, functionally orientated treatment (SDA). The secondary aim was to measure the same patient group’s WTP for dental implants.Methods: Patients who had completed a previous RCT comparing two tooth replacement strategies (RPDs and SDA) were recruited. 59 patients were asked to indicate their WTP for treatment to replace missing teeth in a number of hypothetical scenarios using the payment card method of contingency evaluation coupled to different costs. Data were collected on patients’ social class, longest held occupation, income levels and social circumstances.Results: The median age for the patient sample was 72.0 years (IQR: 71-75 years). Patients who had previously been provided with RPDs indicated that their WTP for this treatment strategy was significantly higher than those patients who had received SDA treatment (Mann-Whitney U Test: p<0.001). This group were also WTP a higher price for SDA treatment than those patients who had previously been treated according to this modality (Mann-Whitney U Test: p=0.005). The results indicated that patients’ age was not correlated with WTP but both social class and current income levels were significantly correlated (Spearman’s rank correlation: p<0.05).Patients in both treatment groups exhibited llittle WTP for dental implant treatment with a median price recorded which was lower than either RPD or SDA treatment.Conclusions: Amongst this patient cohort previous treatment experience had a strong influence on WTP as did social class and current income levels. The patients’ WTP indicated that they did not value dental implants over simpler forms of tooth replacement such as RPDs or a SDA approach.

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Introduction
The role of the pharmacist centers on ensuring the safe and effective use of medicines, including over-the-counter (OTC) medicines. It is important to ascertain pharmacy students’ use and opinions on OTC medicines, given that they are the pharmacists of the future and that this market continues to expand. This study aimed to investigate Queen’s University Belfast (QUB) final year pharmacy students’ use and views on OTC medicines. Scarce work has been conducted in this area to date.

Methods
Following ethical approval and a pilot study, all students (n=155) were invited to participate in a self-completed questionnaire (n=20 questions), distributed at a mandatory class. Descriptive statistics and non-parametric tests (Chi-squared and Mann Whitney U-test) were used for data analyses.

Results
The response rate was 99.4% (154/155). The majority (153/155) reported using OTC medicines; the key consideration during personal product selection was effectiveness. Most [96.1% (147/153)] were in agreement that safety was the over-riding concern during OTC consultations. While 96.1% (149/155) considered that using an evidence-based approach improved the quality of patient care, 68.0% (104/153) would be prepared to sell a product that lacks evidence of effectiveness, provided it would not cause harm.

Conclusions
The importance of evidence of effectiveness was acknowledged, yet many students in this study were prepared to recommend unproven products. Further strategies are required at QUB to ensure this routine consideration alongside safety in practice.

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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Planaltina, Programa de Pós-Graduação em Gestão Pública, Mestrado Profissional em Gestão Pública, 2016.

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The effects oftwo types of small-group communication, synchronous computer-mediated and face-to-face, on the quantity and quality of verbal output were con^ared. Quantity was deiSned as the number of turns taken per minute, the number of Analysis-of-Speech units (AS-units) produced per minute, and the number ofwords produced per minute. Quality was defined as the number of words produced per AS-unit. In addition, the interaction of gender and type of communication was explored for any differences that existed in the output produced. Questionnaires were also given to participants to determine attitudes toward computer-mediated and face-to-face communication. Thirty intermediate-level students fi-om the Intensive English Language Program (lELP) at Brock University participated in the study, including 15 females and 15 males. Nonparametric tests, including the Wilcoxon matched-pairs test, Mann-Whitney U test, and Friedman test were used to test for significance at the p < .05 level. No significant differences were found in the effects of computer-mediated and face-to-face communication on the output produced during follow-up speaking sessions. However, the quantity and quality of interaction was significantly higher during face-to-face sessions than computer-mediated sessions. No significant differences were found in the output produced by males and females in these 2 conditions. While participants felt that the use of computer-mediated communication may aid in the development of certain language skills, they generally preferred face-to-face communication. These results differed fi-om previous studies that found a greater quantity and quality of output in addition to a greater equality of interaction produced during computer-mediated sessions in comparison to face-to-face sessions (Kern, 1995; Warschauer, 1996).

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This study was undertaken to ascertain whether meromictic lakes could be differentiated from holomictic lakes on the basis of their surficial profundal sediments. Surface sediment cores (15 cm long) were collected from both the littoral and profundal zones of four meromictic and six holomictic lakes and analyzed for total number of fossil chironomid headcapsu~es, chlorophyll and carotenoid degradation products as well as \ iron and manganese concentrations. Littoral and profundal comparisons of the surface sediments were made between the two lake types using the Mann-Whitney U test. Iron, manganese and the iron to manganese ratio in the littoral sediments of meromictic lakes were significantly lower than those found in the littoral sediments of holomictic lakes. The observed differences are believed to represent an artifact of the significantly higher carbonate concentrations found in three of the four meromictic lakes studied. Profundal and littoral to profundal ratio comparison between holomictic and meromictic lakes suggest that the significantly lower iron and higher carotenoid concentrations in meromictic profundal sediments were a con~equence of meromixis. However, the overlap in distribution exhibited by both iron and carotenoid degradation products between the two lake types was sufficiently large in this study to nullify their use as a means of differentiating meromictic from holomictic lakes. A long core (4.25 m) was removed from the deepest part of the meromictic Crawford Lake (Ontario), sectioned at 5 cm intervals, and analyzed to assess when meromixis occurred, based on its fossil record. Temporal changes in the total number of chironomid headcapsules, and chlorophyll and carotenoid sediment degradation products were closely correlated with organic matter, indicating in my opinion that extensive redeposition of littoral chironomid headcapsules in the profundal zone has occurred. Temporal variations in carotenoid degradation products, in response to changes in organic matter, obscured increased preservation that may have occurred as a consequence of meromixis. Temporal variations in iron and manganese suggest that relatively stable redox conditions have existed throughout most of the lake's history. Therefore it would appear that Crawford Lake has been meromictic since its inception.

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Introduction Cette recherche constitue une étude clinique descriptive, visant à évaluer la douleur durant le traitement orthodontique avec boîtiers auto-ligaturants passifs et actifs. Matériel et méthode L'étude a été effectuée chez 39 patients (18 garçons, 21 filles), âge moyen 14 (entre 11 et 19 ans). Deux types de boîtiers auto-ligaturants ont été utilisés (SPEED n=20 et Damon n=19). Pour évaluer la douleur, un questionnaire a été élaboré par l'équipe de recherche. L’étude comportait 4 phases, c’est-à-dire l’évaluation de la douleur suite à l’insertion des 4 premiers fils orthodontiques du traitement de chaque patient (0.016 Supercable, 016 CuNiTi, 016X022 CuNiTi, 019X025 CuNiTi). Le même questionnaire était utilisé lors de chaque phase et le questionnaire comprenait 6 différents temps (T0: avant l’insertion du fil orthodontique, T1: immédiatement suite à l’insertion du fil, T2: 5h après l’insertion, T3: 24h après l’insertion, T4: 3 jours après l’insertion, T5: une semaine après l’insertion, T6: 4 semaines après l’insertion) suite à l’insertion de chaque fil. L’échelle visuelle analogue (EVA) et la version courte du questionnaire de Saint-Antoine ont été utilisés afin d’évaluer la douleur. Les données des EVA entre les groupes ont été comparées en utilisant le U test Mann-Whitney. Résultats et discussion Pour les deux premiers fils et pour tous les temps étudiés, il n’y avait pas de différence statistiquement significative entre les deux groupes (SPEED et Damon). Cependant, au moment de l’insertion (T0) du troisième fil (016X022 CuNiTi), parmi les patients ayant rapporté de la douleur (SPEED 47.1%, Damon 55.6%), le groupe Damon a rapporté une douleur significativement plus élevée que le groupe SPEED (p=0.018), (EVA moyenne SPEED=14.14±8.55, Damon=33.85±19.64). Trois jours après l’insertion du troisième fil, toujours parmi les patients ayant rapporté de la douleur (SPEED 23.5%, Damon 33.4%), la douleur était significativement plus élevée chez le groupe Damon que chez le groupe SPEED (p=0.008), (EVA moyenne SPEED=8.74±4.87, Damon=25.15±9.69). La plupart des analgésiques ont été pris suite à la pose du premier fil au temps T2 (5h) et T3 (24h). Il n’y avait pas de différence statistiquement significative entre les groupes en ce qui a trait au nombre de patients qui prenaient des analgésiques. La douleur n’a pas affecté le style de vie pour la grande majorité des patients. Les mots descriptifs sensoriels « tiraillement », « étau » et « élancement » et le mot affectif « énervant » étaient le plus souvent utilisés. Conclusion Les patients du groupe Damon ont ressenti significativement plus de douleur que les patients du groupe SPEED à l’insertion du troisième fil et trois jours suite à l’insertion. Plus de patients ont pris des médicaments pour la douleur avec le premier fil et le style de vie n’était pas affecté pour une majorité de patients. « Tiraillement », « étau », « élancement » et « énervant » étaient les mots descriptifs les plus utilisés par les patients pour décrire leur douleur.