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OBJECTIVE: High-fidelity simulation-based learning, which mimics situation, environmental, and psychological exposure in the clinical setting, potentially helps nursing students acquire knowledge, confidence, and skills in learning clinical skills during the transition from pre-clinical to clinical practice. However, inconsistent evidence on its effect on learning outcomes was presented across the studies. The aim of our study was to review and analyze the effectiveness of high-fidelity simulation on learning outcomes in undergraduate nursing education. MATERIALS AND METHODS: This study was a systematic review and meta-analysis of experimental studies. A literature search was conducted in four databases (CINAHL, SocINDEX, PubMed, and Web of Science) until July 2021. The Cochrane Risk of Bias Tool was used to appraise the studies' quality. The random-effect model was used to conduct a meta-analysis. RESULTS: Fourteen studies were eligible for quantitative synthesis. The pooled effect indicated high-fidelity simulation-based learning significantly increased nursing students' knowledge acquisition (standardized mean difference [SMD]: 1.73, p < 0.001), self-confidence (SMD: 0.56, p= 0.019) and skills performance (SMD: 1.71, p= 0.006). CONCLUSIONS: Stakeholders within the academic institution may consider enculturating the involvement of high-fidelity simulation as part of an innovative teaching strategy in nursing curricula. Therefore, when graduates enter the workforce, they can function quickly and practice confidently in clinical settings without bringing potential harm.
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Bachillerato en Enfermería , Enseñanza Mediante Simulación de Alta Fidelidad , Estudiantes de Enfermería , Humanos , Estudiantes de Enfermería/psicología , Aprendizaje , Competencia ClínicaRESUMEN
Objective: Sensorimotor performance is influential in Chinese handwriting, but few studies have examined the efficacy of sensorimotor-based interventions on Chinese handwriting among primary school students with poor handwriting performance. The study aims to evaluate a sensorimotor-based intervention to improve handwriting in the mainstream primary schools. Methods: This study adopted a two-group pretest-posttest design. An 8-session group-based sensorimotor intervention was delivered to school-aged children (mean ageâ¯=â¯8.1, 68% male). Group A had 2 sessions every week, while Group B had 4 sessions every week. Analysis of variance with repeated measures was used to test the effects. Results: The intervention had a significant time effect (pâ¯<â¯.05) in terms of improving handwriting process (dâ¯=â¯0.33-1.10), manual dexterity (dâ¯=â¯0.57), visual memory (dâ¯=â¯0.70), visual-spatial perception (dâ¯=â¯0.37), and motor and postural skills (dâ¯=â¯0.73). The effect sizes ranged from medium to large. For the handwriting process, time per character had a significant groupâ¯×â¯time interaction, with post hoc analysis showing that Group A had a significantly large effect (dâ¯=â¯1.89, pâ¯<â¯.001) while Group B did not. Conclusions: The group-based sensorimotor intervention programme appeared to show improvements in students with fair skills in writing Chinese characters. It appears that the effect is better if the training sessions are spaced out in one month rather than intensively conducted within two weeks. It might be related to more involvement from parents, and students need more time for practice after the training sessions.
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OBJECTIVES: To determine independent predictors of root resorption for surgical-orthodontic treatment of impacted maxillary central incisors. SETTING AND SAMPLE POPULATION: The Department of Dentistry at Show Chwan Hospital, Changhua, Taiwan. Eighty patients with unilateral osseous-impacted maxillary central incisors receiving a surgical-orthodontic treatment. MATERIAL AND METHODS: This is a retrospective observational study. Root resorption and its predictors were abstracted from patients' charts, pre-treatment cephalometric radiographs, and post-treatment periapical radiographs. Predictors included demographics, treatment duration, crown angle, crown height, crown depth, and root dilacerations. RESULTS: The patients' mean age was 9.2 ± 2.3 years (6.4-20.6 years), and 60% were females. Impacted maxillary central incisors had greater root resorption than naturally erupted contralateral incisors (Δ = -2.8 mm, p < 0.001). Independent predictors of root resorption for impacted maxillary central incisors were shown by linear regression analysis to be crown height (ß = -0.2, p < 0.01), crown depth (ß = -0.3, p = 0.001), treatment duration (ß = 0.2, p < 0.01), and root dilacerations (ß = 3.1, p = 0.001). CONCLUSIONS: Impacted maxillary central incisors had greater root resorption during surgical-orthodontic treatment than their naturally erupted contralateral incisors. Predictors of a greater root resorption were highly and deeply impacted incisors, longer treatment, and root dilacerations. These predictors may help to inform patient and family counseling before treatment.
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Incisivo/diagnóstico por imagen , Resorción Radicular/etiología , Técnicas de Movimiento Dental/métodos , Diente Impactado/diagnóstico por imagen , Adolescente , Cefalometría/métodos , Niño , Femenino , Estudios de Seguimiento , Predicción , Humanos , Masculino , Modelos Dentales , Odontometría/métodos , Hueso Paladar/diagnóstico por imagen , Radiografía de Mordida Lateral , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Corona del Diente/diagnóstico por imagen , Erupción Dental/fisiología , Raíz del Diente/anomalías , Diente Impactado/clasificación , Diente Impactado/cirugía , Adulto JovenRESUMEN
OBJECTIVES: To determine independent predictors of duration of surgical-orthodontic treatment of impacted maxillary central incisors. SETTING AND SAMPLE POPULATION: The Department of Dentistry at Show Chwan Hospital, Changhua, Taiwan. Eighty patients with unilateral osseous impacted maxillary central incisors receiving a surgical-orthodontic treatment. MATERIAL AND METHODS: This is a retrospective observational study. Treatment duration and its predictors were abstracted from the patients' charts and pre-treatment cephalometric radiographs. Predictors included demographics, crown angle, crown height, crown depth, and root dilacerations. RESULTS: The mean age of the cohort was 9.2±2.3 years (6.4-20.6 years), and 60% were women. The mean orthodontic traction time was 8.0±4.5 months (2.0-24.1 months). Using multiple linear regression analysis, the independent predictors of treatment duration for an impacted maxillary central incisor were age (ß=0.9, p<0.001), crown height (ß=-0.2, p<0.05), and root dilacerations (ß=3.8, p<0.001). CONCLUSIONS: Duration of surgical-orthodontic treatment of an impacted maxillary central incisor varied widely. Predictors of longer treatment time were older age, high impacted tooth, and dilacerated incisors.
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Incisivo/patología , Maxilar/patología , Extrusión Ortodóncica/métodos , Diente Impactado/terapia , Adolescente , Factores de Edad , Cefalometría , Niño , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Predicción , Humanos , Incisivo/cirugía , Masculino , Maxilar/cirugía , Estudios Retrospectivos , Factores de Tiempo , Corona del Diente/patología , Raíz del Diente/anomalías , Raíz del Diente/patología , Diente Impactado/cirugía , Adulto JovenRESUMEN
This study investigated a novel drug delivery system (DDS), consisting of polycaprolactone (PCL) or polycaprolactone 20% tricalcium phosphate (PCL-TCP) biodegradable scaffolds, fibrin Tisseel sealant and recombinant bone morphogenetic protein-2 (rhBMP-2) for bone regeneration. PCL and PCL-TCP-fibrin composites displayed a loading efficiency of 70% and 43%, respectively. Fluorescence and scanning electron microscopy revealed sparse clumps of rhBMP-2 particles, non-uniformly distributed on the rods' surface of PCL-fibrin composites. In contrast, individual rhBMP-2 particles were evident and uniformly distributed on the rods' surface of the PCL-TCP-fibrin composites. PCL-fibrin composites loaded with 10 and 20 microg/ml rhBMP-2 demonstrated a triphasic release profile as quantified by an enzyme-linked immunosorbent assay (ELISA). This consisted of burst releases at 2 h, and days 7 and 16. A biphasic release profile was observed for PCL-TCP-fibrin composites loaded with 10 microg/ml rhBMP-2, consisting of burst releases at 2 h and day 14. PCL-TCP-fibrin composites loaded with 20 microg/ml rhBMP-2 showed a tri-phasic release profile, consisting of burst releases at 2 h, and days 10 and 21. We conclude that the addition of TCP caused a delay in rhBMP-2 release. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and alkaline phosphatase assay verified the stability and bioactivity of eluted rhBMP-2 at all time points.
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Líquidos Corporales/química , Proteínas Morfogenéticas Óseas/administración & dosificación , Sustitutos de Huesos/administración & dosificación , Fosfatos de Calcio/química , Implantes de Medicamentos/administración & dosificación , Adhesivo de Tejido de Fibrina/administración & dosificación , Poliésteres/química , Factor de Crecimiento Transformador beta/administración & dosificación , Proteína Morfogenética Ósea 2 , Proteínas Morfogenéticas Óseas/química , Materiales Biocompatibles Revestidos/administración & dosificación , Materiales Biocompatibles Revestidos/química , Difusión , Combinación de Medicamentos , Evaluación Preclínica de Medicamentos , Implantes de Medicamentos/química , Adhesivo de Tejido de Fibrina/química , Ensayo de Materiales , Factor de Crecimiento Transformador beta/químicaRESUMEN
In this study, we first investigated the in vitro degradation properties of biodegradable, bioresorbable polycaprolactone-20% tricalcium phosphate (PCL-TCP) composites immersed in simulated body fluid (SBF) and phosphate buffered saline (PBS). Then, the release profiles of the growth factors present in platelet-rich plasma (PRP) loaded onto the composites incubated in SBF and PBS were compared. Composites immersed in both buffers showed water uptake of 13.7%+/-0.75 at day 1, followed by a constant uptake of 12.1%+/-0.3 until day 12. Henceforth the water uptake declined for SBF- and increased for PBS-soaked composites. The weight loss data did not reveal any trend. SBF- and PBS-soaked samples displayed 1-2% weight loss for 2 and 5 of the ten time points measured respectively. The original protein retention (PR) of the composites was 49.1%+/-1.50. After immersion in SBF and PBS for 4 weeks, the PR was augmented to 88.5%+/-1.40 and 69.1%+/-1.40 correspondingly. PRP after activation contained 164.7+/-24.8, 194+/-43 and 18.3+/-4.75 ng/ml of TGF-beta1, PDGF-BB and IGF-1. Microscopic analysis verified the attachment of PRP to the rods and pores of the composites. Interestingly, the buffers played an important role in determining the release profiles of TGF and PDGF. Firstly, PBS-soaked composites manifested a tri-phasic burst-like profile that was absent in SBF. Secondly, SBF-soaked composites experienced delayed release of the growth factors and total release was not achieved (64.4% for TGF and 60.5% for PDGF), whereas total release was realized for PBS-soaked composites. Lastly, release profiles from SBF-soaked composites were growth factor mediated in terms of their amounts and sizes. This was not observed for PBS-soaked composites. IGF-1, on the other hand, exhibited a progressive reduction in levels over the entire experimental period for both buffers. The mechanisms of release were theorized to be a combination of diffusion, degradation and bioactivity. Since SBF is analogous to our body fluids in terms of its ionic constituents, we expect the elution profiles derived from SBF-soaked samples to more accurately emulate the in vivo situation. In conclusion, this study has deemed PCL-TCP composites as suitable delivery systems for platelet-rich plasma.
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Plaquetas/química , Fosfatos de Calcio/química , Sistemas de Liberación de Medicamentos , Plasma/química , Poliésteres/química , Absorción , Animales , Factor I del Crecimiento Similar a la Insulina/química , Cinética , Microscopía Electrónica de Rastreo , Factor de Crecimiento Derivado de Plaquetas/química , Proteínas/química , Porcinos , Factor de Crecimiento Transformador beta/química , Factor de Crecimiento Transformador beta1 , Agua/químicaRESUMEN
BACKGROUND: Previous data have demonstrated that rofecoxib has good analgesic efficacy for acute postoperative dental pain. However, up to half of these patients require rescue analgesics within the first 24 hours. As the timing of analgesic interventions may be an important factor in pain control, the present study tested the hypothesis that rofecoxib administered preoperatively would improve the analgesic efficacy and reduce rescue analgesic requirements within the first 24 hours compared with postoperative administration. METHODS: This was a double-blind, randomized, crossover study where 45 patients had each of their identical impacted mandibular third molars removed under local anesthesia on 2 separate occasions. Patients acted as their own control; one side was pretreated with rofecoxib 50 mg, 2 hours before surgery, followed by placebo 15 minutes after surgery, and the contralateral side was pretreated with placebo 2 hours before surgery and posttreated with rofecoxib 50 mg 15 minutes after surgery. The difference in postoperative pain between 2 sides was assessed by 4 primary end-points: pain intensity as measured by a 100-mm visual analogue scale hourly for 12 hours, time to rescue analgesic, postoperative analgesic consumption, and patient's global assessment. RESULTS: Patients reported significantly lower pain scores (P = 0.04), longer time to rescue analgesic (P = 0.02), lesser postoperative analgesic consumption (P = 0.008), and better global assessment (P = 0.01) in the pretreated compared with the posttreated sides. There were significantly more patients in the pretreated group who did not required rescue analgesic within the first 24 hours (80% vs. 58%, P = 0.01), and the pain scores were extremely low in both groups during the 12 hours postoperative period (9.8 +/- 5.0 mm vs. 14.3 +/- 7.4 mm). CONCLUSION: Rofecoxib is an excellent analgesic for preventing postoperative dental pain and when given 2 hours preoperatively rendered most patients relatively pain free, requiring no rescue analgesics on the first postoperative day.
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Inhibidores de la Ciclooxigenasa/uso terapéutico , Lactonas/uso terapéutico , Procedimientos Quirúrgicos Orales/efectos adversos , Dolor Postoperatorio/prevención & control , Sulfonas/uso terapéutico , Acetaminofén/uso terapéutico , Analgésicos no Narcóticos/uso terapéutico , Área Bajo la Curva , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Lateralidad Funcional , Humanos , Dimensión del Dolor , Dolor Postoperatorio/etiología , Estudios Prospectivos , Estudios Retrospectivos , Factores de TiempoRESUMEN
Minority game is a simple-mined econophysical model capturing the cooperative behavior among selfish players. Previous investigations, which were based on numerical simulations up to about 100 players for a certain parameter alpha in the range 0.1 < approximately alpha < approximately 1, suggested that memory is irrelevant to the cooperative behavior of the minority game in the so-called symmetric phase. Here using a large scale numerical simulation up to about 3000 players in the parameter range 0.01 < approximately alpha < approximately 1, we show that the mean variance of the attendance in the minority game actually depends on the memory in the symmetric phase. We explain such dependence in the framework of crowd-anticrowd theory. Our findings conclude that one should not overlook the feedback mechanism buried under the correlation in the history time series in the study of minority game.
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INTRODUCTION: Dental implants are increasingly used to restore missing dentition. These titanium implants are surgically installed in the edentulous alveolar ridge and allowed to osteointegrate with the bone during the healing phase. After osseo-integration, the implant is loaded with a prosthesis to replace the missing tooth. Conventional implant treatment planning uses study models, wax-ups and panoramic x-rays to prefabricate surgical stent to guide the preparation of the implant site. The drilling into the alveolar ridge is invariably a "blind" procedure as the part of the drill in bone is not visible. Stereotactic systems were first introduced into neurosurgery in 1986. Since then, computer-assisted navigational technology has brought major advances to neuro-, midface and orthopaedic surgeries, and more recently, to implant placement. CLINICAL FEATURE: This paper illustrates the use of real-time computer-guided navigational technology in enhancing safety in implant surgical procedures. OUTCOME AND CONCLUSION: Real-time computer-guided navigational technology enhances accuracy and precision of the surgical procedure, minimises complications and facilitates surgery in challenging anatomical locations.
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Implantación Dental/métodos , Cirugía Asistida por Computador , Femenino , Humanos , Masculino , SeguridadRESUMEN
Information technology can help to improve health care delivery. The utilisation of informatics principle enhances the quality of nursing practices through improved communication, documentation and efficiency. The Nursing Profession constitutes 34% of the total workforce in the Hong Kong Hospital Authority (HA) and includes 21,000 nurses in 2012. To enhance the quality of care and patient safety in both hospitals and community care setting, it is essential that an integrated electronic decision support system for nurses is designed to track documentation and support care or service including observations, decisions, actions and outcomes throughout the care process at each point-of-care. The Patient Care Plan project was set up to achieve these objectives. The Project adheres to strict documentation information architecture to ensure data sharing is freely available. Preliminary results showed very promising improvement in clinical care.
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Sistemas de Apoyo a Decisiones Clínicas , Planificación de Atención al Paciente , Sistemas de Apoyo a Decisiones Clínicas/organización & administración , Hong Kong , Humanos , Difusión de la Información , Planificación de Atención al Paciente/organización & administración , Planificación de Atención al Paciente/estadística & datos numéricos , Sistemas de Atención de Punto , Mejoramiento de la CalidadRESUMEN
OBJECTIVE: To test the hypothesis that axonal damage extending into primarily normal-appearing white matter is clinically important by comparing the concentrations of N-acetylaspartate (NAA) bilaterally within the internal capsule with lateralization of motor impairment in patients with multiple sclerosis (MS) and persistent asymmetrical motor deficit. DESIGN: We performed magnetic resonance spectroscopy and T2-weighted imaging of the internal capsule, calculated central motor conduction times, and related these results to measures of motor function asymmetry in 12 patients with MS. RESULTS: Levels of NAA from normal-appearing white matter of the internal capsule in patients with MS were significantly lower than those in control subjects (P = .05). Side-to-side differences in NAA levels were also significantly greater in patients with MS than in controls (P = .01). There was a correlation between asymmetry in motor function for the left and right limbs and asymmetry of internal capsule NAA concentrations (r = 0.60; P = .04). This correlation seemed slightly stronger when tests specifically of arm and hand motor asymmetry were considered alone. Central motor conduction times were abnormal in most patients with MS and showed a side-to-side difference that also correlated with asymmetry in motor function. CONCLUSION: Our demonstration of a graded association between NAA concentrations within primarily normal-appearing white matter of a specific tract and functional impairments referable to that tract suggests that axonal pathology distant from macroscopic lesions might be an important determinant of disability in MS.
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Axones/patología , Cápsula Interna/patología , Trastornos del Movimiento/patología , Esclerosis Múltiple/patología , Adulto , Anciano , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análisis , Axones/química , Estimulación Eléctrica , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Magnetismo , Masculino , Persona de Mediana Edad , Trastornos del Movimiento/etiología , Esclerosis Múltiple/complicaciones , Conducción NerviosaRESUMEN
Our strategy entails investigating the influence of varied concentrations (0, 10, 100 and 1000ng/ml) of human recombinant bone morphogenetic protein-2 (rhBMP-2) on the osteogenic expression of canine osteoblasts, seeded onto poly-caprolactone 20% tricalcium phosphate (PCL-TCP) scaffolds in vitro. Biochemical assay revealed that groups with rhBMP-2 displayed an initial burst in cell growth that was not dose-dependent. However, after 13 days, cell growth declined to a value similar to control. Significantly less cell growth was observed for construct with 1000ng/ml of rhBMP-2 from 20 days onwards. Confocal microscopy confirmed viability of osteoblasts and at day 20, groups seeded with rhBMP-2 displayed heightened cell death as compared to control. Phase contrast and scanning electron microscopy revealed that osteoblasts heavily colonized surfaces, rods and pores of the PCL-TCP scaffolds. This was consistent for all groups. Finally, Von Kossa and osteocalcin assays demonstrated that cells from all groups maintained their osteogenic phenotype throughout the experiment. Calcification was observed as early as four days after stimulation for groups seeded with rhBMP-2. In conclusion, rhBMP-2 seems to enhance the differentiated function of canine osteoblasts in a non-dose dependent manner. This resulted in accelerated mineralization, followed by death of osteoblasts as they underwent terminal differentiation. Notably, PCL-TCP scaffolds seeded only with canine osteoblasts could sustain excellent osteogenic expression in vitro. Hence, the synergy of PCL with bioactive TCP and rhBMP-2 in a novel composite scaffold, could offer an exciting approach for bone regeneration.
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Materiales Biocompatibles , Proteínas Morfogenéticas Óseas/farmacología , Osteoblastos/efectos de los fármacos , Poliésteres , Factor de Crecimiento Transformador beta/farmacología , Animales , Proteína Morfogenética Ósea 2 , Células Cultivadas , Perros , Matriz Extracelular , Microscopía Electrónica de Rastreo , Osteoblastos/ultraestructura , Proteínas Recombinantes/farmacologíaRESUMEN
OBJECTIVE: Paired transcranial magnetic stimuli (TMS) were applied in 8 multiple sclerosis (MS) patients with asymmetrical clinical signs and in 8 healthy controls to test the hypothesis that the circuits responsible for the generation and transmission of I-waves are abnormal in the former group METHODS: A figure-of-8 coil discharging through a Magstim 200/Bistim configuration delivered identical stimuli at an intensity 10% above the motor threshold of the relaxed first dorsal interosseous muscle. The interstimulus intervals (ISIs) used were varied in a pseudo-randomized fashion in steps of 0.2 ms between 1.0 and 5 ms. RESULTS: In 9 of 12 unilateral studies in the control group, a pattern of 3 peaks of increased motor evoked potential size was found at ISIs of 1.2-1.6 ms, 2.4-3.2 ms and 4.4-5.0 ms. A similar pattern was present in only 5 of 12 studies in the patients (Fisher's exact test, P = 0.1), while it was absent in all the 4 studies of the side with greater clinical involvement in patients (P = 0.01) CONCLUSION: Our results suggest that I-wave generation is more likely to be defective in MS than in normal subjects, that this defect resides in the cortex, and that it correlates with severity of physical signs.
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Potenciales Evocados Motores/fisiología , Magnetismo , Esclerosis Múltiple/fisiopatología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de TiempoRESUMEN
A placebo effect on post-operative swelling was investigated as a possible model for studying psychological influences on recovery from surgery. 79 patients undergoing removal of impacted third-molars received one of five different procedures shortly after emerging from general anaesthetic. These included dentist-administered or placebo ultrasound (the latter given in two different ways to control for massage effects), untreated controls and a group instructed to apply facial massage to themselves. Pre- and post-operative measurements included trait and state-anxiety, coping style, emotional state, pain, plasma cortisol and facial swelling. Cortisol levels correlated with anxiety and avoidant coping. Post-operative anxiety was negatively correlated with pre-operative arousal. Neither coping nor emotional state was affected by the treatments, but swelling was reduced by a placebo effect of ultrasound. Cortisol levels also responded, apparently to an effect of massage. The coping and emotional factors which we measured here cannot, therefore, explain the effects of this psychological procedure on post-operative recovery.
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Adaptación Psicológica , Tercer Molar/cirugía , Complicaciones Posoperatorias/psicología , Rol del Enfermo , Extracción Dental , Diente Impactado/cirugía , Adolescente , Adulto , Nivel de Alerta , Edema/psicología , Edema/terapia , Femenino , Humanos , Hidrocortisona/sangre , Masculino , Masaje/psicología , Complicaciones Posoperatorias/terapia , Terapia por Ultrasonido/psicologíaRESUMEN
Despite decades of animal experiments, data on blast injury to the lung cover only a limited number of circumstances and are in a fragmented form. This paper develops a mathematical model of the chest wall dynamics and the subsequent generation of strong pressure waves within the lung, which have been hypothesized as the mediator of injury. The model has been compared to an extensive database of observed pathologies from animal tests. The incidence of injury and lethality is found to follow a log-normal correlation with the computed total energy in these waves and, when the energy is normalized by the lung volume, the lethality correlation applies to all large animal species. Small animals also correlate with the normalized energy, but at a different value, and it is speculated that structural differences, other than lung volume, may be involved. This relatively simple model allows the potential for blast injury to the lung to be determined from measured or computed pressure traces without additional animal testing. Improved occupational exposure criteria should follow from this methodology.
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Traumatismos por Explosión/fisiopatología , Lesión Pulmonar , Modelos Biológicos , Animales , Traumatismos por Explosión/patología , Modelos Animales de Enfermedad , Transferencia de Energía , Humanos , Incidencia , Sistemas de Información , Modelos Logísticos , Pulmón/patología , Pulmón/fisiopatología , Exposición Profesional , Presión , Ovinos , Estrés Mecánico , Tasa de Supervivencia , Traumatismos Torácicos/patología , Traumatismos Torácicos/fisiopatología , Tórax/patología , Tórax/fisiopatologíaRESUMEN
AIMS: This study introduces a non-invasive method based on computed tomography (CT) verification to ensure patients are accurately positioned before fractionated stereotactic radiotherapy. It enables quality control of mask positioning with reference to the CT images of the treatment plan. MATERIALS AND METHODS: A mask system, together with a dental impression moulded mouth bite, was used for patient immobilisation. In order to facilitate relevant image comparison, special alignment during CT localisation was discussed in the study. The accuracy of patient set-up was studied by assessing the isocentre position in relation to the patient's anatomical structure. The planning CT images were applied as a reference and the study was applied to 261 cranial applications. RESULTS: The results show that the mean and the maximum overall displacements at the isocentre were 0.7 and 2.5 mm, respectively. The mean and the maximum rotational displacement in the axial plane were 0.56 degrees and 2 degrees, respectively. The mean translational displacement and rotational displacement were close to zero when considering the direction of movement. CONCLUSIONS: The results indicate that the systematic error of the mask system and the verification method are minimal. Advantages of this technique include the simple set-up, three-dimensional quantification and short study time (10-15 min). It is therefore practical to implement on a routine basis. Investigation of the ability to relocate the mask is also recommended to justify the required safety margin between the clinical and planning target volumes.
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Máscaras , Radioterapia Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Fraccionamiento de la Dosis de Radiación , HumanosRESUMEN
To demonstrate the usefulness of physical approaches for the study of realistic economic systems, we investigate the inequality of players' wealth in one of the most extensively studied econophysical models, namely, the minority game (MG). We gauge the wealth inequality of players in the MG by a well-known measure in economics known as the modified Gini index. From our numerical results, we conclude that the wealth inequality in the MG is very severe near the point of maximum cooperation among players, where the diversity of the strategy space is approximately equal to the number of strategies at play. In other words, the optimal cooperation between players comes hand in hand with severe wealth inequality. We also show that our numerical results in the asymmetric phase of the MG can be reproduced semianalytically using a replica method.
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The use of a pedicled buccal fat pad graft to line the cheek defect after excision of a large oral leukoplakia is described. The advantages of this fat graft over a split-thickness skin graft are discussed.
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Tejido Adiposo/trasplante , Leucoplasia Bucal/cirugía , Mucosa Bucal/cirugía , Anciano , Mejilla , Humanos , MasculinoRESUMEN
We describe a 20-year-old male Singaporean army recruit with hereditary, congenital mirror movements who presented with difficulties in military training because releasing the grip of one hand resulted in a similar release by the other hand. His father has mirror movements with a significant decrease in symptoms with time, a phenomenon that has not been previously described. Both father and son have no associated neurological abnormalities. Bilateral cortical representation for hand muscles and the presence of active ipsilateral corticospinal projections have been postulated as the mechanisms responsible for this condition.
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Brazo/fisiopatología , Discinesias/fisiopatología , Adulto , Discinesias/congénito , Discinesias/genética , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Our two patients presented with Wernicke's Encephalopathy (WE) resulting from prolonged hyperemesis gravidarum. This is an unusual cause of WE, a potentially fatal medical emergency due to thiamine deficiency. We discuss the clinical settings, presentation, diagnosis, neurophysiological and radiological findings, treatment and outcome of WE in these two cases and the neuropathologic correlation of this condition. We stress upon the importance of early diagnosis and prompt treatment of WE.