Exclusive gene mapping of congenital microphthalmia in a Chinese family

Congenital microphthalmia is a developmental ocular disorder and might be caused by the mutations in the genes involved in eye development. To uncover the genetic cause in a six-generation Chinese pedigree with autosomal dominant congenital microphthalmia

Use of eye lens diameter and weight as an age indicator in the carangid fish, Decapterus russelli (Pisces: Carangidae) from Gulf of Oman: preliminary observation

Specimens of Decapterus russelli have been collected from Lema, north of the Gulf of Oman. The ocular lens diameter and weight were tested as an additional age indicator to those already in use. The results showed that this technique could be adopted for determining the age of the species Decapterus russelli when the specimens are in the second year of age in case of eye lens diameter. On the other hand, eye lens weight failed to separate between the four age groups observed. The method is especially useful for age determination when otolith or scale ring are not visible or when false rings give erroneous reading.

Structural optimization of lattice materials

Lattice materials are characterized at the microscopic level by a regular pattern of voids confined by walls. Recent rapid prototyping techniques allow their manufacturing from a wide range of solid materials, ensuring high degrees of accuracy and limited costs. The microstructure of lattice material permits to obtain macroscopic properties and structural performance, such as very high stiffness to weight ratios, highly anisotropy, high specific energy dissipation capability and an extended elastic range, which cannot be attained by uniform materials. Among several applications, lattice materials are of special interest for the design of morphing structures, energy absorbing components and hard tissue scaffold for biomedical prostheses. Their macroscopic mechanical properties can be finely tuned by properly selecting the lattice topology and the material of the walls. Nevertheless, since the number of the design parameters involved is very high, and their correlation to the final macroscopic properties of the material is quite complex, reliable and robust multiscale mechanics analysis and design optimization tools are a necessary aid for their practical application. In this paper, the optimization of lattice materials parameters is illustrated with reference to the design of a bracket subjected to a point load. Given the geometric shape and the boundary conditions of the component, the parameters of four selected topologies have been optimized to concurrently maximize the component stiffness and minimize its mass. Copyright © 2011 by ASME.

Fabrication and control of miniature McKibben actuators

This paper investigates the development of miniature McKibben actuators. Due to their compliancy, high actuation force, and precision, these actuators are on the one hand interesting for medical applications such as prostheses and instruments for surgery and on the other hand for industrial applications such as for assembly robots. During this research, pneumatic McKibben actuators have been miniaturized to an outside diameter of 1.5 mm and a length ranging from 22 mm to 62 mm. These actuators are able to achieve forces of 6 N and strains up to about 15% at a supply pressure of 1 MPa. The maximal actuation speed of the actuators measured during this research is more than 350 mm/s. Further, positioning experiments with a laser interferometer and a PI controller revealed that these actuators are able to achieve sub-micron positioning resolution. © 2010 Published by Elsevier B.V. All rights reserved.

Time-dependent fracture toughness of cornea.

The fracture and time-dependent properties of cornea are very important for the development of corneal scaffolds and prostheses. However, there has been no systematic study of cornea fracture; time-dependent behavior of cornea has never been investigated in a fracture context. In this work, fracture toughness of cornea was characterized by trouser tear tests, and time-dependent properties of cornea were examined by stress-relaxation and uniaxial tensile tests. Control experiments were performed on a photoelastic rubber sheet. Corneal fracture resistance was found to be strain-rate dependent, with values ranging from 3.39±0.57 to 5.40±0.48kJm(-2) over strain rates from 3 to 300mmmin(-1). Results from stress-relaxation tests confirmed that cornea is a nonlinear viscoelastic material. The cornea behaved closer to a viscous fluid at small strain but became relatively more elastic at larger strain. Although cornea properties are greatly dependent on time, the stress-strain responses of cornea were found to be insensitive to the strain rate when subjected to tensile loading.

A novel implantable multichannel silicon-based microelectrode

Silicon-based microelectrodes have been confirmed to be helpful in neural prostheses. The fabricated 7-channel silicon-based microelectrode was feasible to be implanted into the brain cortex. The manufacturing process by microelectromechanical system (MEMS) technology was detailed with four photolithographic masks. The microscopic photographs and SEM images indicated that the probe shank was 3mm long, 100 mu m wide and 20 mu m thick with the recording sites spaced 120 mu m apart for good signal isolation. To facilitate the insertion and minimize the trauma, the microelectrode is narrowed down gradually near the tip with the tip taper angle of 6 degrees. Curve of the single recording site impedance versus frequency was shown by test in vitro and the impedance declined from 150.5 k Omega to 6.0 k Omega with frequency changing from 10 k to 10MHz.

incremental learning of triadic plsa for collaborative filtering

Beijing University of Technology (BJUT); Beijing Municipal Lab of Brain Informatics; Chinese Society of Radiology; National Natural Science Foundation of China (NSFC); State Administration of Foreign Experts Affairs

PROTRACTED HYPOFRACTIONATED RADIOTHERAPY for GRAVES' OPHTHALMOPATHY: A PILOT STUDY of CLINICAL and RADIOLOGIC RESPONSE

Purpose: To evaluate the clinical and radiologic response of patients with Graves' ophthalmopathy given low-dose orbital radiotherapy (RT) with a protracted fractionation.Methods and Materials: Eighteen patients (36 orbits) received orbital RT with a total dose of 10 Gy, fractionated in 1 Gy once a week over 10 weeks. of these, 9 patients received steroid therapy as well. Patients were evaluated clinically and radiologically at 6 months after treatment. Clinical response assessment was carried out using three criteria: by physical examination, by a modified clinical activity score, and by a verbal questionnaire considering the 10 most common signs and symptoms of the disease. Radiologic response was assessed by magnetic resonance imaging.Results: Improvement in ocular pain, palpebral edema, visual acuity, and ocular motility was observed in all patients. Significant decrease in symptoms such as tearing (p < 0.001) diplopia (p = 0.008), conjunctival hyperemia (p = 0.002), and ocular grittiness (p = 0.031) also occurred. Magnetic resonance imaging showed decrease in ocular muscle thickness and in the intensity of the T2 sequence signal in the majority of patients. Treatments were well tolerated, and to date no complications from treatment have been observed. There was no statistical difference in clinical and radiologic response between patients receiving RT alone and those receiving RT plus steroid therapy.Conclusion: RT delivered in at a low dose and in a protracted scheme should be considered as a useful therapeutic option for patients with Graves' ophthalmopathy. (C) 2012 Elsevier Inc.

Uso de equipamento auxiliar no preparo dentário para próteses

Trabalho apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária.

Quorum Sensing na Prática Clínica

Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas

Estudo da prevalência das alterações biológicas e mecânicas associadas à reabilitação com prótese parcial removível nas clínicas pedagógicas de Medicina Dentária da FCS-UFP

Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária

Infected vision in the works of Thomas Middleton

This thesis investigates the extent and range of the ocular vocabulary and themes employed by the playwright Thomas Middleton in context with early modern scientific, medical, and moral-philosophical writing on vision. More specifically, this thesis concerns Middleton’s revelation of the substance or essence of outward forms through mimesis. This paradoxical stance implies Middleton’s use of an illusory (theatrical) art form to explore hidden truths. This can be related to the early modern belief in the imagination (or fantasy) as chief mediator between the corporeal and spiritual worlds as well as to a reformed belief in the power of signs to indicate divine truth. This thesis identifies striking parallels between Middleton’s policy of social diagnosis and cure and an increased preoccupation with knowledge of interior man which culminates in Robert Burton’s Anatomy of Melancholy of 1621. All of these texts seek a cure for diseased internal sense faculties (such as fantasy and will) which cause the raging passions to destroy the individual. The purpose of this thesis is to demonstrate how Middleton takes a similar ‘mental-medicinal’ approach which investigates the idols created by the imagination before ‘purging’ the same and restoring order (Corneanu and Vermeir 184). The idea of infection incurred through the eyes which are fixed on vice (or error) has moral, religious, and political implications and discovery of corruption involves stripping away the illusions of false appearances to reveal the truth within whereby disease and disorder can be cured and restored. Finally, Middleton’s use of theatrical fantasy to detect the idols of the diseased imagination can be read as a Paracelsian, rather than Galenic, form of medicine whereby like is ‘joined with their like’ (Bostocke C7r) to restore health.

A qualitative study of trends in patient preferences for the management of partial dentition

Objective: To identify factors influencing attitudes of partially dentate adults towards dental treatment in Ireland. Background: People are retaining more teeth later in life than ever before. Management of partially dentate older adults will be a major requirement for the future and it is important to determine factors which may influence patients’ attitudes to care. Methods: Subjects: A purposive sample of 22 partially dentate patients was recruited; 12 women and 12 men, ranging in age from 45 to 75 years. Data Collection: Semi-structured individual interviews. Results: Dental patients have increasing expectations in relation to (i) a more sophisticated approach to the management of missing teeth and (ii) their right to actively participate in decision making regarding the management of their tooth loss. There is some evidence of a cohort effect with younger patients (45–64 years) having higher expectations. Conclusions: The evidence of a cohort effect within this study in relation to higher patient expectations indicates that both contemporary and future patients are likely to seek a service based on conservation and restoration of missing teeth by fixed prostheses.

Spatial vision in the purple sea urchin Strongylocentrotus purpuratus (Echinoidea).

Recent evidence that echinoids of the genus Echinometra have moderate visual acuity that appears to be mediated by their spines screening off-axis light suggests that the urchin Strongylocentrotus purpuratus, with its higher spine density, may have even more acute spatial vision. We analyzed the movements of 39 specimens of S. purpuratus after they were placed in the center of a featureless tank containing a round, black target that had an angular diameter of 6.5 deg. or 10 deg. (solid angles of 0.01 sr and 0.024 sr, respectively). An average orientation vector for each urchin was determined by testing the animal four times, with the target placed successively at bearings of 0 deg., 90 deg., 180 deg. and 270 deg. (relative to magnetic east). The urchins showed no significant unimodal or axial orientation relative to any non-target feature of the environment or relative to the changing position of the 6.5 deg. target. However, the urchins were strongly axially oriented relative to the changing position of the 10 deg. target (mean axis from -1 to 179 deg.; 95% confidence interval +/- 12 deg.; P<0.001, Moore's non-parametric Hotelling's test), with 10 of the 20 urchins tested against that target choosing an average bearing within 10 deg. of either the target center or its opposite direction (two would be expected by chance). In addition, the average length of the 20 target-normalized bearings for the 10 deg. target (each the vector sum of the bearings for the four trials) were far higher than would be expected by chance (P<10(-10); Monte Carlo simulation), showing that each urchin, whether it moved towards or away from the target, did so with high consistency. These results strongly suggest that S. purpuratus detected the 10 deg. target, responding either by approaching it or fleeing it. Given that the urchins did not appear to respond to the 6.5 deg. target, it is likely that the 10 deg. target was close to the minimum detectable size for this species. Interestingly, measurements of the spine density of the regions of the test that faced horizontally predicted a similar visual resolution (8.3+/-0.5 deg. for the interambulacrum and 11+/-0.54 deg. for the ambulacrum). The function of this relatively low, but functional, acuity - on par with that of the chambered Nautilus and the horseshoe crab - is unclear but, given the bimodal response, is likely to be related to both shelter seeking and predator avoidance.

Automatic segmentation of seven retinal layers in SDOCT images congruent with expert manual segmentation.

Segmentation of anatomical and pathological structures in ophthalmic images is crucial for the diagnosis and study of ocular diseases. However, manual segmentation is often a time-consuming and subjective process. This paper presents an automatic approach for segmenting retinal layers in Spectral Domain Optical Coherence Tomography images using graph theory and dynamic programming. Results show that this method accurately segments eight retinal layer boundaries in normal adult eyes more closely to an expert grader as compared to a second expert grader.