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1.
Insects ; 15(5)2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38786924

RESUMO

The global decline in the number of pollinators has elicited considerable public attention. To the general public, honeybees are considered to be the primary pollinators. Also, a decline in managed honeybee stocks is alarming and could lead to declining pollination services and reduced ecosystem biodiversity, although the Apis mellifera is the least likely pollinator species on the planet to be at risk of extinction. A less-than-complete understanding of honeybees and their ecology may hinder their conservation. Ascertaining the public's level of knowledge about, and perception of, a problem can help in solving it. This research focused mainly on honeybees because people are unlikely to be able to recognize the different species of Apoidea. Schools are ideal places for understanding the basic knowledge and attitudes regarding this insect. We aimed to understand the perception and knowledge of 12-14-year-old children towards honeybees as well as to verify the existence of a correlation between knowledge level and positive perception. Secondary school students can play a key role in the conservation of biodiversity as they are carriers of knowledge in families and will be future citizens. To this end, 231 students were given a 26-item questionnaire related to their perception and knowledge of honeybees. Results indicate that the students have a good understanding of the role that bees play in nature but do not have a completely clear idea of this insect's interactions with the environment. Results also show that the children feel a certain fear of honeybees, although they respect them. The average score of the ecological branch test exceeded the average score of the perceptual one, indicating that the subjects had a more positive education than perception.

2.
Front Psychol ; 15: 1346556, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38680287

RESUMO

Introduction: Based on the job demands-resources (JD-R) model, the present study aimed to validate "The Technical and Administrative Staff Quality of Life At Work" (TASQ@work), a new tool to assess the quality of life at work in academia focused on technical and administrative staff. Methods: This tool was developed by the QoL@Work research team, a group of expert academics in the field of work and organizational psychology affiliated with the Italian Association of Psychologists. The TASQ@work was elaborated in different steps. The first phase was aimed at the identification of the dimensions of the tool. The second phase was aimed to assess the psychometric properties of the tool. The validation process involved confirmatory analysis and measurement invariance of the various constructs selected. The analyses were performed in a convenience sample of two Italian universities in different regions (one in the Northwest and the second in Central Italy). Results: The sample was composed of 1820 Administrative Staff, comprising 69.4% from University 1 (N = 1,263) and 30.6% from University 2 (N = 557). The TASQ@work presented satisfactory psychometric properties (normality of the items, reliability and content, construct and nomological validity) and measurement invariance across gender, seniority, and Athenaeum. Discussion: The results indicate that the tool can be considered a reliable and valid instrument to assess job demands, job resources, and outcomes in the working life of technical and administrative academic staff. In this perspective, the present study represents the first contribution to the debate on the psychosocial risks in academic contexts by presenting a new tool, the TASQ@work, aimed at contextualizing the JD-R model to understand the role played by psychosocial aspects in affecting the well-being of the academic employees.

3.
Nurs Health Sci ; 25(4): 619-627, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37786237

RESUMO

This study aims to investigate the weight of surface acting (a condition in which subjects must display an emotional state that does not correspond to their real feelings) in the relationship between the emotional load of nursing work and the perception of health, and to evaluate the moderating effect of age and length of service. A moderated mediation analysis was conducted on a sample of 359 Italian nurses. The results confirmed the mediation role of surface acting and showed that both age and seniority have moderating effects so that in conditions of high emotional load, older and more experienced nurses show higher levels of surface acting, and in conditions of high surface acting, younger and less experienced nurses show lower levels of perceived health. In conclusion, surface acting seems a stressor for younger nurses, not yet used to the weight of faking emotions, while the perceived emotional load seems a stressor for older and more experienced nurses. Each result highlights the importance of providing emotional regulation skills training and support to reduce the psychological impact of emotional demands on nurses.


Assuntos
Esgotamento Profissional , Regulação Emocional , Enfermeiras e Enfermeiros , Humanos , Emoções , Nível de Saúde , Inquéritos e Questionários , Satisfação no Emprego , Esgotamento Profissional/psicologia
4.
Nurs Forum ; 57(6): 1258-1266, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35975337

RESUMO

AIMS: This study aims to verify the association between nurses' perception of the meaningfulness of their work and their pleasure in working, and whether this relationship may change based on the level of deep acting performed to cope with emotional regulation demands and the influence of the COVID-19 pandemic on the healthcare work. METHODS: Nurses from both private and public Italian institutions (N = 239) completed an online questionnaire between June 2021 and January 2022. A moderated moderation model was tested through SPSS Process macro. The design is cross-sectional. RESULTS: The results show that the perception of meaningfulness of work is positively associated with pleasure in working, especially in conditions of high deep acting. This relationship is further moderated by the COVID-19 influence so that the association between meaningful work and pleasure in working is stronger in conditions of high COVID-19 influence and at higher levels of deep acting performed. CONCLUSION: Perceiving one's work as meaningful can be a job resource that protects nurses from the negative effects of emotional regulation demands and even from the stress of dealing with COVID-19. IMPACT: The study addresses the problem of nurses' emotional regulation demands at work and evaluates the protective role of meaningful work. The findings could be useful for planning prevention interventions (through training in adaptive emotional regulation strategies) or protection interventions (through the promotion of effective coping strategies and the stimulation of one's work engagement).


Assuntos
Esgotamento Profissional , COVID-19 , Enfermeiras e Enfermeiros , Humanos , Prazer , Estudos Transversais , Pandemias , Inquéritos e Questionários , Satisfação no Emprego , Esgotamento Profissional/etiologia , Esgotamento Profissional/psicologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-35457670

RESUMO

The aim of the study was to verify whether the frequency of face-to-face interactions with the public at work can reveal differences in how people react to emotional regulation demands. In particular, we investigated the mediating role of surface acting (a strategy of dealing with emotional dissonance) in the relationship between two typical job stressors (workload and mental load) and two outcomes closely related to work-related well-being: employees' general health and the need for recovery. Prior studies investigating the detrimental effects of emotional dissonance mostly focused on service workers. However, in light of a survey conducted by the European Agency for Safety and Health at Work (2016) highlighting the growing psycho-social risk constituted by intense human interactions in the workplaces, even in unexpected categories of workers, we hypothesize that emotional demands may also be a concern for those who do not specifically interface with clients as part of their job duties. The results of the multi-group analysis of front-office (N = 734) and back-office (N = 436) Italian workers showed that surface acting fully mediates the relationship between workload and general health among back-office workers, while it only partially mediates this relationship among front-office workers. Furthermore, surface acting is positively associated with the need for recovery and negatively with general health, with higher values for back-office workers. The findings support the hypothesis that the emotional demands are not only a service worker issue and highlight the need to address emotional regulation strategies to enhance the quality of life in and outside the workplace for all employees.


Assuntos
Satisfação no Emprego , Qualidade de Vida , Emoções , Humanos , Inquéritos e Questionários , Carga de Trabalho/psicologia , Local de Trabalho/psicologia
6.
Sensors (Basel) ; 22(7)2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35408387

RESUMO

Teaching is an activity that requires understanding the class's reaction to evaluate the teaching methodology effectiveness. This operation can be easy to achieve in small classrooms, while it may be challenging to do in classes of 50 or more students. This paper proposes a novel Internet of Things (IoT) system to aid teachers in their work based on the redundant use of non-invasive techniques such as facial expression recognition and physiological data analysis. Facial expression recognition is performed using a Convolutional Neural Network (CNN), while physiological data are obtained via Photoplethysmography (PPG). By recurring to Russel's model, we grouped the most important Ekman's facial expressions recognized by CNN into active and passive. Then, operations such as thresholding and windowing were performed to make it possible to compare and analyze the results from both sources. Using a window size of 100 samples, both sources have detected a level of attention of about 55.5% for the in-presence lectures tests. By comparing results coming from in-presence and pre-recorded remote lectures, it is possible to note that, thanks to validation with physiological data, facial expressions alone seem useful in determining students' level of attention for in-presence lectures.


Assuntos
Reconhecimento Facial , Internet das Coisas , Expressão Facial , Humanos , Redes Neurais de Computação , Fotopletismografia
7.
Artigo em Inglês | MEDLINE | ID: mdl-35329409

RESUMO

The present study provides evidence for a valid and reliable tool, the Academic Quality at Work Tool (AQ@workT), to investigate the quality of life at work in academics within the Italian university sector. The AQ@workT was developed by the QoL@Work research team, namely a group of expert academics in the field of work and organizational psychology affiliated with the Italian Association of Psychologists. The tool is grounded in the job demands-resources model and its psychometric properties were assessed in three studies comprising a wide sample of lecturers, researchers, and professors: a pilot study (N = 120), a calibration study (N = 1084), and a validation study (N = 1481). Reliability and content, construct, and nomological validity were supported, as well as measurement invariance across work role (researchers, associate professors, and full professors) and gender. Evidence from the present study shows that the AQ@workT represents a useful and reliable tool to assist university management to enhance quality of life, to manage work-related stress, and to mitigate the potential for harm to academics, particularly during a pandemic. Future studies, such as longitudinal tests of the AQ@workT, should test predictive validity among the variables in the tool.


Assuntos
Qualidade de Vida , Humanos , Itália , Projetos Piloto , Reprodutibilidade dos Testes , Inquéritos e Questionários
8.
Virtual Real ; : 1-14, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34642567

RESUMO

Virtual reality (VR) and augmented reality (AR) applications are very diffuse nowadays. Moreover, recent technology innovations led to the diffusion of commercial head-mounted displays for immersive VR: users can enjoy entertainment activities that fill their visual fields, experiencing the sensation of physical presence in these virtual immersive environments. Even if AR and VR are mostly used separately, they can be effectively combined to provide a multi-user shared environment (SE), where two or more users perform some specific tasks in a cooperative or competitive way, providing a wider set of interactions and use cases compared to immersive VR alone. However, due to the differences between the two technologies, it is difficult to develop SEs offering a similar experience for both AR and VR users. This paper presents Harmonize, a novel framework to deploy applications based on SEs with a comparable experience for both AR and VR users. Moreover, the framework is hardware-independent, and it has been designed to be as much extendable to novel hardware as possible. An immersive game has been designed to test and to evaluate the validity of the proposed framework. The assessment of the system through the System Usability Scale questionnaire and the Game Experience Questionnaire shows a positive evaluation.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33375635

RESUMO

Although many studies have been conducted to evaluate the risk and protective factors on psychological health among academic staff, little attention has been paid to fixed-term researchers, the weakest figures in the academic context. By using the Job Demands-Resources model as theoretical framework, we investigated: (1) the role of some job demands (workload, mental load, and emotional dissonance) in predicting the need for recovery; (2) the role of some job resources (independence, career opportunities, and work-life balance) in predicting work engagement; and (3) the moderating role of the contract type (more or less precarious). We focused in particular on emotional dissonance (the discrepancy between emotions that need to be displayed and what is really felt), assuming its unique role in predicting fatigue. Results of structural equation modeling analysis generally supported our hypotheses and highlighted a so far undiscovered path between mental load and work engagement. Specifically, mental load leads to fatigue only indirectly through workload and emotional dissonance, while significantly predicting the absorption and the dedication of fixed-term Italian researchers. The latter relationship was also moderated by the contract type, so that mental load predicts dedication especially among researchers in the most precarious condition.


Assuntos
Esgotamento Profissional , Emoções , Pesquisadores/psicologia , Engajamento no Trabalho , Humanos , Itália , Satisfação no Emprego , Inquéritos e Questionários , Carga de Trabalho
10.
Medicina (Kaunas) ; 56(1)2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31968622

RESUMO

Background and Objectives: To compare the long-term toxicity of infracyanine green (IFCG) to brilliant blue G (BBG) in inverted internal limiting membrane flap surgery (I-ILMFS) for large, full-thickness macular holes (FTMHs). Materials and Methods: Prospective randomized study including 39 eyes with ≥ 400 µm idiopathic FTMH who underwent I-ILMFS with either IFCG or BBG. Postoperative 6- and 12-month corrected distance visual acuity (CDVA), closure rate, and swept-source optical coherence tomography parameters, including ellipsoid zone (EZ) and external limiting membrane (ELM) mean defect length, central foveal thicknesses (CFT), parafoveal macular thickness (MT), ganglion cells and inner plexiform layer (GCL++) thickness, and peripapillary nerve fiber layer (pRNFL) thickness, were compared. Results: Nineteen eyes were included in the IFCG group and 20 eyes in the BBG group. In all cases a FTMH closure was found. CDVA improved at 6 and 12 months in both groups (p < 0.0005); the increase at 12 months was greater in the BBG group (p = 0.036). EZ and ELM defects did not differ between groups at either follow-up time. CFT at 12 months was greater in the BBG group (p = 0.041). A 12-months compared to 6-months MT decrease was present in both groups (p < 0.01). The GCL++ superior inner sector was thicker in the BBG group at 12 months (p = 0.036), as were the superior outer sector (p = 0.039 and p = 0.027 at 6 and 12 months, respectively) and inferior outer sector (p = 0.011 and p = 0.009 at 6 and 12 months, respectively). Conclusion: In our study BBG in I-ILMFS exhibits better long-term CDVA and retinal thickness than does IFCG, suggesting a lesser toxicity from BBG. These findings support the use of BBG over IFCG in I-ILMFS.


Assuntos
Meios de Contraste , Verde de Indocianina/análogos & derivados , Perfurações Retinianas/cirurgia , Corantes de Rosanilina , Tomografia de Coerência Óptica/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retina/diagnóstico por imagem , Retina/cirurgia , Perfurações Retinianas/diagnóstico por imagem , Retalhos Cirúrgicos/cirurgia , Resultado do Tratamento
11.
Front Robot AI ; 6: 18, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-33501034

RESUMO

Nowadays the market is becoming increasingly competitive, factories are required not only to enhance the product quality but also to reduce manufacturing and maintenance times. In an industrial context, modern factories are composed by many automated systems, such as industrial robots, which can perform different tasks. Although industrial robots are becoming more powerful and efficient, human workers are still required to accomplish different operations, such as training and maintenance procedures. The proposed research aims to assess a remote interaction system in an industrial training collaborative mixed-reality (CMR) environment. A remote expert user is capable of explaining a training procedure to an unskilled local user. Remote and local users interact using different interaction systems: the remote operator gives assistance using an immersive Virtual Reality (VR) device, whereas the local user interacts using a wearable Augmented Reality (AR) device. A comparison between an interaction based on the presence of a virtual human and one based on the use of abstract icons is proposed. In the first case, a virtual 3D representation of the remote technician is shown to the local user by using AR: the remote technician can pinpoint the components involved in the training procedure and the local user can visualize the instructions through some animations of the virtual avatar. In the second case, the local user cannot see a 3D representation of the remote technician; on the other hand, different 3D models, such as animated icons, are displayed to the local operator through AR depending on the component pinpointed by the remote technician in the virtual environment. Each 3D icon should suggest to the local user which component has to be manipulated at the current step of the procedure. Preliminary results suggest that the interface that requires less resources to be developed and managed should be preferred. Although in no audio condition the virtual avatar may improve the sense of presence of the remote technician, the use of abstract metaphors seems to be of primary importance to successfully complete an industrial task.

12.
13.
Nutrients ; 10(9)2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-30231532

RESUMO

Lutein is a carotenoid with reported anti-inflammatory properties. A large body of evidence shows that lutein has several beneficial effects, especially on eye health. In particular, lutein is known to improve or even prevent age-related macular disease which is the leading cause of blindness and vision impairment. Furthermore, many studies have reported that lutein may also have positive effects in different clinical conditions, thus ameliorating cognitive function, decreasing the risk of cancer, and improving measures of cardiovascular health. At present, the available data have been obtained from both observational studies investigating lutein intake with food, and a few intervention trials assessing the efficacy of lutein supplementation. In general, sustained lutein consumption, either through diet or supplementation, may contribute to reducing the burden of several chronic diseases. However, there are also conflicting data concerning lutein efficacy in inducing favorable effects on human health and there are no univocal data concerning the most appropriate dosage for daily lutein supplementation. Therefore, based on the most recent findings, this review will focus on lutein properties, dietary sources, usual intake, efficacy in human health, and toxicity.


Assuntos
Dieta , Suplementos Nutricionais , Oftalmopatias/prevenção & controle , Olho , Luteína/administração & dosagem , Animais , Olho/metabolismo , Olho/patologia , Olho/fisiopatologia , Oftalmopatias/metabolismo , Oftalmopatias/patologia , Oftalmopatias/fisiopatologia , Humanos , Estado Nutricional , Valor Nutritivo , Prognóstico , Fatores de Proteção , Fatores de Risco
15.
BMC Ophthalmol ; 16: 24, 2016 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-26946419

RESUMO

BACKGROUND: Clinical studies comparing trabeculectomy augmented with Ologen implant (OLO) versus trabeculectomy plus mitomycin-C (MMC) show contradictory results. To obtain long-term data, we report an extended 5-year follow-up trial evaluating the safety and efficacy of OLO as adjuvant compared to low-dosage MMC in trabeculectomy. METHODS: Forty glaucoma patients (40 eyes) assigned to trabeculectomy with MMC or Ologen. PRIMARY OUTCOME: target IOP at ≤21, ≤17 and ≤15 mmHg; complete and qualified success endpoint rates. SECONDARY OUTCOMES: visual acuity (VA), mean deviation (MD), bleb evaluation, according to Moorfields Bleb Grading System (MBGS); spectral domain OCT (SD-OCT) bleb examination; number of glaucoma medications; frequency of postoperative complications. RESULTS: The mean preoperative IOP was 26.7(±5.2) in MMC and 27.3(±6.0) in OLO eyes. Mean 60-month percentage reduction in IOP was significant in both groups [40.9 (±14.2) and 42.1(±13.3) P = 0.01], with an endpoint value of 15.2 (±3.2) and 15.8 (±2.3) mmHg in MMC and OLO, respectively. Complete success rates at ≤ 21 mmHg target IOP were 65% and 70%, at ≤17 mm Hg 60% and 55%, and at the ≤15 mm Hg target IOP 35% and 45% in MMC and OLO, respectively. The Kaplan-Meier curves did not differ both for complete and qualified success at any target IOP, with no significant endpoint intergroup difference at ≤ 15 mm Hg (log-rank P = 0.595).The intergroup MBGS scores differed due to reduced central and peripheral vascularity in MMC group (P = 0.027; P = 0.041). SD-OCT analysis denied differences in bleb height between MMC vs OLO (140.5 ± 20.3 µ vs 129.2 ± 19.3 µ respectively; P =0.079). Mean antiglaucoma medications were significantly reduced (P < 0.0005) from 2.5 (±0.3) to 1.2 (±0.4) in MMC and from 2.6 (±0.2) to 1.4 (±0.3) in OLO group, with no intergroup differences (P = 0.08). Six (30%) cystic thin avascular blebs without oozing were recorded in the MMC group and 2 (10%) in the OLO group, without intergroup difference (P = 0.235). CONCLUSIONS: Our extended follow-up results confirm that Ologen implant yields efficacy and long-term success rates quite similar to MMC, with at least equivalent safety.


Assuntos
Implantes Absorvíveis , Alquilantes/administração & dosagem , Colágeno , Glaucoma de Ângulo Aberto/cirurgia , Glicosaminoglicanos , Mitomicina/administração & dosagem , Trabeculectomia/métodos , Adulto , Idoso , Síndrome de Exfoliação/fisiopatologia , Síndrome de Exfoliação/cirurgia , Feminino , Seguimentos , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia
16.
Oncology ; 86(2): 72-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24401657

RESUMO

BACKGROUND: Recently, attention has been focused on physicians' stress and quality-of-life improvement. Due to their relationship with patients, oncologists in particular are overloaded physically, emotionally and psychologically. Previous studies showed that training of communication skills improves the satisfaction and well-being of physicians and patients. AIMS: Our research investigates the relationship between work stress and engagement and personal well-being in physicians working in Italian hospitals. MATERIALS AND METHODS: 176 physicians were included. Doctors filled out self-report questionnaires to evaluate work stress and coping strategies, personal well-being, work engagement and two purpose-built scales to measure the degree of perceived organizational support and the level of specific training of social and relational skills. Descriptive statistics were used to analyze data, as well as correlation analysis (Pearson's r), hierarchical regression analysis (enter step) and analysis of variance (one-way ANOVA). RESULT: Positive and significant correlations were found between variables. Moreover, physicians who obtained higher levels of specific training on social and relational skills reported lower levels of stress. Oncologists experienced greater stress than other physicians in terms of maladaptive coping and lack of additional training. CONCLUSIONS: The study suggests that physicians' well-being is mediated by professional aspects, such as social skills in relationships with patients.


Assuntos
Médicos/psicologia , Adulto , Idoso , Feminino , Humanos , Itália , Masculino , Oncologia , Pessoa de Meia-Idade , Padrões de Prática Médica , Qualidade de Vida , Estresse Psicológico/epidemiologia , Inquéritos e Questionários
17.
BMC Infect Dis ; 12: 226, 2012 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-23006858

RESUMO

BACKGROUND: Ocular syphilis is often difficult to diagnose because of the wide variation in clinical features.HIV co-infection may further complicate the picture. CASE PRESENTATION: Herein the authors report an unusual primary syphilitic ocular lesion in a 45-year-old Italian HIV-infected bisexual man who presented with a unilateral eyelid lesion. Associated precocious signs and symptoms in the posterior segment of both eyes, bilateral chorioretinitis and uveitis, are described. Intravenous penicillin and steroid treatment produced a rapid improvement in clinical status and complete resolution. CONCLUSIONS: Careful questioning about sexual behavior is crucial for unmasking unusual features of ocular syphilis in HIV-infected subjects.


Assuntos
Cancro/diagnóstico , Coriorretinite/etiologia , Pálpebras/patologia , Infecções por HIV/complicações , Uveíte/diagnóstico , Anti-Inflamatórios/administração & dosagem , Cancro/tratamento farmacológico , Cancro/patologia , Coriorretinite/tratamento farmacológico , Coriorretinite/patologia , Humanos , Injeções Intravenosas , Itália , Masculino , Pessoa de Meia-Idade , Penicilinas/administração & dosagem , Esteroides/administração & dosagem , Resultado do Tratamento , Uveíte/tratamento farmacológico , Uveíte/patologia
18.
Med. oral patol. oral cir. bucal (Internet) ; 16(6): 852-856, sept. 2011. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-93102

RESUMO

Objective: To evaluate the biomechanical scenario of platform switching geometric implant-abutment configurationrelative to standard configurations by means of finite element analysis.Study Design: A 3D Finite Element Analysis (FEA) was performed on 3 different implant-abutment configurations:a 3.8 mm implant with a matching diameter abutment (Standard Control Design, SCD), a 5.5 mm implantwith matching diameter abutment (Wider Control Design, WCD), and a 5.5mm implant with a 3.8 mm abutment(Experimental Design, ED). All the different experimental groups were discretized to over 60000 elements and100000 nodes, and 130N vertical (axial) and 90N horizontal loads were applied on the coronal portion of the abutment.Von Mises stresses were evaluated and maximum and minimum values were acquired for each implantabutmentconfiguration.Results: The load-induced Von Mises stress (maximum to minumum ranges) on the implant ranged from 150MPa to 58 Pa (SCD); 45 MPa to 55 Pa (WCD); 190 MPa to 64 Pa (ED). The Von Mises stress on the abutmentranged from 150 MPa to 52 MPa (SCD); 70 MPa to 55 MPa (WCD), and 85 MPa to 42 MPa respectively (ED). Themaximum stresses transmitted from the implant-abutment system to the cortical and trabecular bone were 67 Paand 52 MPa (SCD); 54 Pa and 27 MPa (WCD); 64 Pa and 42 MPa (ED), respectively. When the implant body wasevaluated for stresses, a substantial decrease in their levels were observed at the threaded implant region due tothe diametral mismatch between implant and abutment for the ED configuration.Conclusion: The platform switching configuration led to not only to a relative decrease in stress levels comparedto narrow and wide standard configurations, but also to a notable stress field shift from bone towards the implantsystem, potentially resulting in lower crestal bone overloading (AU)


No disponible


Assuntos
Humanos , /métodos , Implantação Dentária/métodos , Fenômenos Biomecânicos , Implantes Dentários
19.
Med Oral Patol Oral Cir Bucal ; 16(6): e852-6, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21743409

RESUMO

OBJECTIVE: To evaluate the biomechanical scenario of platform switching geometric implant-abutment configuration relative to standard configurations by means of finite element analysis. STUDY DESIGN: A 3D Finite Element Analysis (FEA) was performed on 3 different implant-abutment configurations: a 3.8 mm implant with a matching diameter abutment (Standard Control Design, SCD), a 5.5 mm implant with matching diameter abutment (Wider Control Design, WCD), and a 5.5mm implant with a 3.8 mm abutment (Experimental Design, ED). All the different experimental groups were discretized to over 60000 elements and 100000 nodes, and 130N vertical (axial) and 90N horizontal loads were applied on the coronal portion of the abutment. Von Mises stresses were evaluated and maximum and minimum values were acquired for each implant-abutment configuration. RESULTS: The load-induced Von Mises stress (maximum to minumum ranges) on the implant ranged from 150 MPa to 58 Pa (SCD); 45 MPa to 55 Pa (WCD); 190 MPa to 64 Pa (ED). The Von Mises stress on the abutment ranged from 150 MPa to 52 MPa (SCD); 70 MPa to 55 MPa (WCD), and 85 MPa to 42 MPa respectively (ED). The maximum stresses transmitted from the implant-abutment system to the cortical and trabecular bone were 67 Pa and 52 MPa (SCD); 54 Pa and 27 MPa (WCD); 64 Pa and 42 MPa (ED), respectively. When the implant body was evaluated for stresses, a substantial decrease in their levels were observed at the threaded implant region due to the diametral mismatch between implant and abutment for the ED configuration. CONCLUSION: The platform switching configuration led to not only to a relative decrease in stress levels compared to narrow and wide standard configurations, but also to a notable stress field shift from bone towards the implant system, potentially resulting in lower crestal bone overloading.


Assuntos
Dente Suporte , Projeto do Implante Dentário-Pivô , Análise de Elementos Finitos , Fenômenos Biomecânicos , Análise do Estresse Dentário , Imageamento Tridimensional
20.
World J Gastroenterol ; 15(18): 2287-9, 2009 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-19437573

RESUMO

Schwannoma is a well-described, benign nerve sheath tumor of the soft tissue, but is rare in the gastrointestinal tract. Gastrointestinal schwannomas are often incidentally discovered as small polypoid intraluminal lesions. In this report, we describe the clinicopathologic and immunohistochemical features of a distinctive neural mucosal polyp composed of a diffuse cellular proliferation of uniform bland spindled cells in the lamina propria that entraps the colonic crypts. Immunohistochemical analysis revealed strong and diffuse positivity for the S-100 protein. To avoid confusion of these solitary colorectal polyps containing pure spindled Schwann cell proliferation in the lamina propria with neural lesions that have significant association with inherited syndromes, it is better to use the designation "mucosal Schwann hamartoma".


Assuntos
Hamartoma/patologia , Neurilemoma/patologia , Células de Schwann/patologia , Neoplasias Gástricas/patologia , Feminino , Hamartoma/classificação , Hamartoma/diagnóstico , Humanos , Pessoa de Meia-Idade , Neurilemoma/classificação , Neurilemoma/diagnóstico , Neoplasias Gástricas/classificação , Neoplasias Gástricas/diagnóstico
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