Epsilon-and-mu-near-zero (EMNZ) metamaterial structure inspired UHF antenna for nanosatellite has been proposed in this paper. The antenna consists of 3 × 2-unit cell array on the ground plane and a meander line radiating patch. Coaxial probe feeding technique has been obtained to excite the antenna. The meander line enables the antenna to resonate at lower UHF band and the metamaterial array is used to make the resonant frequency stable by reducing the coupling effect with metallic nanosatellite structure. The metamaterial structure exhibits EMNZ characteristics from 385 MHz to 488.5 MHz, which facilitates stable resonant frequency and higher antenna efficiency when embedded with nanosatellite structure. The proposed EMNZ inspired antenna has achieved measured impedance bandwidth (S11 orbit nanosatellite communications.
Craniosynostosis is a premature pathologic fusion of one or more cranial vault sutures leading to abnormally-shaped skull. It can occur in isolated event (non-syndromic), or it can occur in conjunction with other anomalies in welldefined patterns (syndromic). The diagnosis rests on clinical examination and confirmation is generally on the computed tomography scan. The need for surgery is both for cosmetic and functional reasons. Here we describe a case of nonsyndromic craniosynostosis that was treated with frontal orbital advancement (FOA). The potential benefits of FOA need to be carefully weighed against the potential complications when deciding for any surgical intervention.
Selulitis orbital merupakan jangkitan tisu di sekitar mata di dalam ruangan orbit yang
termasuk saraf mata. Ia boleh menyebabkan komplikasi yang membawa kematian
sekiranya merebak melalui saraf mata dan ke otak. Penyebab utama jangkitan
adalah termasuk perebakan jangkitan sinusitis dari ruangan paranasal atau melalui
selulitis preseptal. Kes ini menggambarkan jangkitan di luar kebiasaan mengenai
jangkitan orbital selulitis yang berlaku akibat luka torehan pada konjunktiva mata
yang disebabkan oleh kemalangan. Rawatan antibiotik sistemik yang agresif
mengurangkan risiko komplikasi penglihatan. Kesemua luka pada atau sekelililng
mata haruslah dirawat dengan sebaiknya bagi mengelakkan berlakunya komplikasi
Markov map is one example of interval maps where it is a piecewise expanding
map and obeys the Markov property. One well-known example of Markov map is the
doubling map, a map which has two subintervals with equal partitions. In this paper, we
are interested to investigate another type of Markov map, the so-called skewed doubling
map. This map is a more generalized map than the doubling map. Thus, the aims of this
paper are to find the fixed points as well as the periodic points for the skewed doubling
map and to investigate the sensitive dependence on initial conditions of this map. The
method considered here is the cobweb diagram. Numerical results suggest that there exist
dense of periodic orbits for this map. The sensitivity of this map to initial conditions is
also verified where small differences in initial conditions give different behaviour of the
orbits in the map.
Orbital fractures and the concomitant soft tissue injuries within the bony orbit result in well-recognized complications such as diplopia and enophthalmos. Guidelines for timing and indications for surgery for achieving an optimal outcome remain elusive. This study examined the effects of timing and fracture type on the outcome of orbital fracture repair.
Comet Lulin was discovered by Lin Chi-Sheng and Ye Quanzhi using the 16-inch telescope at Lulin Observatory in Nantou, Taiwan in 2007. According to Brian Marsden of the Smithsonian Astrophysical Observatory, it reached its perihelion on 10 January 2009 at a distance of 113 million
km from the Sun. It moves in a very nearly parabolic retrograde (‘backwards’ compared to the movement of the planets) orbit at an inclination of 1.6 degrees from the ecliptic (“Newfound Comet Lulin to Grace Night Skies”). http://www.space.com/spacewatch/090206-ns-cometlulin.html). It passed nearest to the Earth at a distance of 61 million km on 23 February 2009.
Comet 17P/Holmes was discovered by Edwin Holmes on 6 November 1892 while he was conducting regular observations of the Andromeda Galaxy (M31). Calculations using observation of its orbits established the perihelion date as 13 June and the orbital period as 6.9 years. The 1899 and 1906 appearances were observed, but the comet was only seen again in 1964. The comet has since been
observed on every subsequent return.
Thyroid eye disease is an autoimmune inflammatory disorder of the orbit in adults. It causes inflammation, expansion and fibrosis of orbital fat, muscles and the lacrimal gland, leading to facial disfigurement, functional disability and, in severe cases, blindness. Overall, approximately 20% of affected patients need some form of surgical intervention requiring anaesthesia. This narrative review explores the background of thyroid eye disease, surgical procedures performed and their implications for anaesthesia. General anaesthesia is used for orbital decompression procedures, strabismus correction surgery and complex oculoplastic procedures. Local anaesthetic infiltration or regional anaesthesia under monitored anaesthesia care are the techniques most commonly employed for eyelid retraction surgery. It is important to limit the volume of local anaesthetic agent used during infiltration and continuously monitor the orbital volume and ocular pressure with a ballottement technique. In addition, the contralateral eye should be checked and, if necessary, protected against corneal exposure. Retrobulbar, peribulbar and sub-Tenon's blocks are best avoided. Topical anaesthesia has been used for some strabismus correction surgery but its use is limited to motivated and cooperative patients only.
Spin field-effect transistors (SpinFETs) are promising candidates for future integrated microelectronic circuits. A SpinFET is composed of two ferromagnetic contacts (source and drain), which sandwich a semiconductor channel. Current modulation is achieved by electrically tuning the gate voltage dependent strength of the spin-orbit interaction in the semiconductor region. We investigated the properties of SpinFETs for various parameters - the band mismatch, the barrier height between the contacts and the channel and the strength of the spin-orbit coupling, for various temperatures. We demonstrated that the creation of Schottky barriers between the channel and the contacts guarantees a pronounced modulation of the magnetoresistance sufficient to open a possibility to operate SpinFETs at room temperature. We also demonstrated that silicon fins with  orientation exhibit a stronger dependence on the value of the spin-orbit interaction and are thus preferable for practical realization of silicon-based SpinFETs.
Intraorbital foreign bodies (IOrbFB) are associated with both sight and life threatening injuries. We report a case of an IOrbFB associated with retrobulbar hemorrhage and injury of the frontal sinus in an 11 year-old boy, after history of fall from the tree. Imaging studies revealed a metallic foreign body (FB) in the orbit and fracture of the walls of the frontal sinus. The usual entry route of an IOrbFB is either through the eye or orbital walls and extremely rare through the paranasal sinuses. This is the first reported case of a FB entering the orbit through the frontal sinus.
A single nostril associated with alobar holoprosencephaly is a rare congenital lesion. This paper reports two female term neonates with holoprosencephaly. The first neonate asphyxiated at birth had a single nostril, hypotelorism, posterior cleft palate, inferonasal coloboma of the iris and disc and persistent tunica vasculosa lentis. The other neonate had cleft lip and palate and recurrent convulsions. Both neonates had gross motor and developmental delay. Cranial sonography and CT scan showed features consistent with alobar holoprosencephaly. Karyotyping for the first neonate and her family members was normal. Both of them were treated conservatively and supervised.
Our aim was to examine the relations between type and site of the fracture, age of the patient, and the management and outcomes, among children diagnosed with orbital fractures at the Women's and Children's Hospital, Adelaide, during a 10-year period from 1 January 2003 to 31 December 2012. The records of 41 children whose ages ranged from 8 months to 15 years were analysed. There was a male predominance (n=33). Two most common fractures were orbital floor and multiwalled fractures, with medial wall as the second most common site. The most common cause of injury was sport, more often with increasing age. In contrast, falls were more common among young children. Fractures of the orbital roof were more common among young children, all of ours being in children 10 years old or less. Lateral wall fractures were also more common among young children and declined in frequency with increasing age. In contrast, fractures of the orbital floor and medial wall can occur at any age, though those of the medial wall were more common among older children. As children grow their behaviour and activities change, and the mechanism by which they become injured also changes. Growth and development of the craniofacial skeleton lead to differences in the patterns of fractures with age. Fractures of the orbital roof and lateral wall are more common among young children, while those of the orbital floor and medial wall can occur at any age.
Tujuan kajian ini adalah untuk menerokai kaedah pembantu penanda permukaan terhadap implan orbital untuk pembedahan tulang orbit. Enam tengkorak manusia dewasa kering telah digunakan dalam kajian ini. Implan orbital aluminium yang disediakan secara individu, dengan ketebalan 0.4 mm disediakan untuk lantai orbit secara bilateral. Empat penanda permukaan implan fizikal dari aspek anterior dan posterior implan yang disediakan dan diimbas secara optik. Pemeriksaan pra-pembedahan tomografi berkomputer ‘cone-beam’ (CBCT) diperolehi untuk semua lantai orbit. Data 'Digital Imaging and Communications in Medicine' (DICOM) tengkorak diambil, diimport dan direka bentuk dengan format data stereolithografi (STL) implan orbital masing-masing menggunakan iPlan CMF (Versi 3.0, BrainLab, Jerman). Teknik gabungan imej dilakukan untuk setiap tengkorak selepas pembinaan semula dengan pengambilan pos-pembedahan CBCT. Pengukuran berasaskan daripada data tomografi terhadap posisi implant kemudian dinilai di antara kedudukan implan yang direncanakan dan yang direalisasikan dalam satah sagittal dan coronal. Analisa statistik dijalankan menggunakan Statistik Statistik PASW® 18. Hasil kajian menunjukkan bahawa 38 daripada 48 penanda permukaan yang dinilai menunjukkan peningkatan ketinggian kedudukan dalam skala kecil pasca-pembedahan berbanding dengan kedudukan implan orbital maya. Semakan metrik Euclidean menunjukkan perbezaan yang kurang daripada 1.00 mm dalam semua penanda permukaan kecuali pada kawasan lej posterior dan anterior dalam penilaian satah sagittal. Kajian ini menunjukkan bahawa penempatan penanda permukaan terhadap implant orbit dalam pembedahan navigasi orbit menyumbang kepada kedudukan implan orbital secara konsisten.
A 40-year-old man presented with right eye axial proptosis and ophthalmoplegia for 3 months. Imaging study showed a right intraconal mass with the erosion of the orbital floor. Incisional biopsy revealed mucoepidermoid carcinoma. Nasal endoscopy was normal and systemic tumor screening was negative for a primary source. The patient underwent right orbital exenteration, uncinectomy, nasal and maxillary mucosal biopsy. Malignant cells were found present in the mucosa of maxillary sinus roof and uncinate bone. The postoperative positron emission tomography scan showed residual active lesion in right orbital apex and maxilla but no primary lesion elsewhere. The patient subsequently underwent 35 cycles of postoperative radiotherapy. Primary mucoepidermoid carcinoma of the orbit is rare and typically arises from the lacrimal gland or sac. Those tumors not arising from lacrimal apparatus should be presumed metastatic in origin, and the thorough systemic survey should be undertaken in the search for the primary tumor.
Matched MeSH terms: Orbit/surgery; Orbital Neoplasms/diagnosis*; Orbital Neoplasms/surgery; Orbit Evisceration
Langerhan cell histiocytosis is a rare disease and usually occurs in paediatric age group. This disease may involve single or multiple organs system and has an unpredictable course of disease. The involvement of head and neck region are almost 90% of cases, however maxillary sinus involvement is very rare. We report a case of 2 year old boy presented with multi organ LCH (orbit, skull, sinus and liver). The mainstay treatment for this high risk multi organ LCH group is chemotherapy. Unfortunately, although with the advancement of treatment, their mortality rate is still high.
Sinus surgery has the potential of allowing ENT surgeons to encroach the boundaries of our colleagues in ophthalmology and neurosurgery. The advent of nasal endoscope and lately powered instrumentation and computer-assisted navigational systems has avoided the use of the conventional and more radical approaches by the ENT surgeon for the treatment of inflammatory pathology or tumors of the orbit and skull base. As rhinologists have gained more experience in endoscopic surgery, more areas related to the orbit and the anterior skull base are accessible and surgery is safer.
Sinonasal tumors may grow to considerable size before presentation and in view of their relation to the base of skull, orbit, cranial nerves and vital vessels; a precise diagnostic and therapeutic planning is needed to achieve the optimal results. We report a case who presented with unilateral nasal blockage, rhinorrhea and episodes of epistaxis which diagnosed as sinonasal inverted papilloma and angiofibroma.
Enucleation is the removal of the entire globe of the eye and a portion of the optic nerve, while evisceration involves the removal of the contents of the globe leaving the sclera, extraocular muscles, and optic nerve. Following enucleation or evisceration, intraorbital implants are routinely placed to enhance the prosthetic outcome in addition to restoring the lost orbital volume. Current practice employs intraorbital implants made of nonporous silicone, hydroxyapatite, or porous polyethylene. Intraorbital implant selection and placement, being a highly demanding procedure in terms of knowledge, skill, and expertise, may be associated with a multiplicity of technical and surgical errors. Complications are usually minimal with these implants, but they do occur. The literature reveals many articles related to intraorbital implants, their benefits, and complications; however, the literature regarding the effect of various intraorbital implant situations on the subsequent prosthetic rehabilitation is markedly scarce. Moreover, the need for interdisciplinary surgical and prosthetic interventions required for successful rehabilitation in cases of compromised implant situations has been underemphasized. Hence, this review aimed to evaluate the effect of different intraorbital implant situations on ocular rehabilitation and the required interdisciplinary surgical and prosthetic treatment approach for rehabilitation of enucleated/eviscerated sockets with compromised implant situations, to provide a critical appraisal, and to present a simplified management strategy.
Ultraviolet radiation is at shorter wavelengths than the visible spectrum (400 to 700 nm) and is divided into three components: UV-A (315 to 400 nm), UV-B (280 to 315 nm), and UV-C (less than 280 nm). Global increases in UV-B fluxes from decreasing stratospheric ozone amounts caused by anthropogenic chlorine releasing gases (mostly chlorofluorocarbons) have been a matter of public concern for the past 20 years. This surface UV irradiance data retrieved from Ozone Monitoring Instrument (OMI) from AURA spacecraft with the filename OMUVB. OMUVB contains surface UV irradiance data along with supplementary information generated using the OMI global mode measurements. In this mode each file contains the sunlit portion of a single orbit from pole-to-pole, with an approximately 2600 km wide swath composed of 60 ground pixels. The OMI measurements are used to estimate the ultraviolet (UV) radiation reaching the Earth’s surface. The product contains spectral irradiances at 305.1, 310.1, 324.1, and 380.1 nm corresponding to both the overpass time and the local solar noon. Using the correspondence latitude and longitude of Peninsular Malaysia, we can develop the pattern of distribution of UV irradiance interpolations using Sigma Plot and Adobe Photoshop.
Patients who lost their eyes as results of accidents or diseases (e.g. retinoblastoma) usually underwent enucleation or evisceration. They were then fi tted with ocular prosthesis to prevent collapse of the globe and also for cosmetic effects. Custom made ocular prosthesis is almost unheard of in this country for most hospitals supply ready-made (stock) prosthesis. The cosmetic results of stock prosthesis are often unsatisfactory. Besides being uncomfortable, stock prosthesis may also induce allergic reaction that may lead to papillary conjunctivitis. The Optometry Clinic at UKM started its custom made prosthetic service in 2010. We described here two cases of patients who complained of discomfort with their old stock prosthesis and re-fitted with custom made prosthesis. We also highlight the importance of proper hygiene and maintenance so that ocular prosthesis can be used for as long as possible. This article aims to create awareness among eye care practitioners and showcase the cosmetic benefi ts of custom made ocular prosthesis.
Study site: Optometry clinic, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia