72 research outputs found

    The accuracy of three-dimensional prediction of soft tissue changes following the surgical correction of facial asymmetry: an innovative concept

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    The accuracy of three-dimensional (3D) predictions of soft tissue changes in the surgical correction of facial asymmetry was evaluated in this study. Preoperative (T1) and 6–12-month postoperative (T2) cone beam computed tomography scans of 13 patients were studied. All patients underwent surgical correction of facial asymmetry as part of a multidisciplinary treatment protocol. The magnitude of the surgical movement was measured; virtual surgery was performed on the preoperative scans using Maxilim software. The predicted soft tissue changes were compared to the actual postoperative appearance (T2). Mean (signed) distances and mean (absolute) distances between the predicted and actual 3D surface meshes for each region were calculated. The one-sample t-test was applied to test the alternative hypothesis that the mean absolute distances had a value of <2.0 mm. A novel directional analysis was applied to analyse the accuracy of the prediction of soft tissue changes. The results showed that the distances between the predicted and actual postoperative soft tissue changes were less than 2.0 mm in all regions. The predicted facial morphology was narrower than the actual surgical changes in the cheek regions. 3D soft tissue prediction using Maxilim software in patients undergoing the correction of facial asymmetry is clinically acceptable

    Accuracy of generic mesh conformation: the future of facial morphological analysis

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    Three-dimensional (3D) analysis of the face is required for the assessment of changes following surgery, to monitor the progress of pathological conditions and for the evaluation of facial growth. Sophisticated methods have been applied for the evaluation of facial morphology, the most common being dense surface correspondence. The method depends on the application of a mathematical facial mask known as the generic facial mesh for the evaluation of the characteristics of facial morphology. This study evaluated the accuracy of the conformation of generic mesh to the underlying facial morphology. The study was conducted on 10 non-patient volunteers. Thirty-four 2-mm-diameter self-adhesive, non-reflective markers were placed on each face. These were readily identifiable on the captured 3D facial image, which was captured by Di3D stereophotogrammetry. The markers helped in minimising digitisation errors during the conformation process. For each case, the face was captured six times: at rest and at the maximum movements of four facial expressions. The 3D facial image of each facial expression was analysed. Euclidean distances between the 19 corresponding landmarks on the conformed mesh and on the original 3D facial model provided a measure of the accuracy of the conformation process. For all facial expressions and all corresponding landmarks, these distances were between 0.7 and 1.7 mm. The absolute mean distances ranged from 0.73 to 1.74 mm. The mean absolute error of the conformation process was 1.13 ± 0.26 mm. The conformation of the generic facial mesh is accurate enough for clinical trial proved to be accurate enough for the analysis of the captured 3D facial images

    Aquatic Oligochaetes of Iraq's Southern Marshes

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    Aquatic Oligochaetes community in the Iraqi southern marshes, Al- Hawiezah, Al-Chibayish and Al-Hammar, have been studied for the period from July 2006 to June 2007. Two sites within each marsh, in addition to a reference site located at Shatt Al-Garma, have been chosen for sample collection using Ekman dredge. The results revealed that the highest average annual density was 16800 individual / m2 recorded in Al-Hawiezah marsh, while in Al-Chibayish and al-Hammar marsh the density did not exceed 5111 individual/m2. In contrast, the density of Oligochaetes recorded in Shatt Al-Garma was about 10500 individual / m2. The highest monthly density was recorded in April 2007.The highest local percentage occurrence was 96% recorded in Al-Hawiezah marsh, while the highest average monthly percentage occurrence was recorded in January 2007.The study revealed the presence of 19 Oligochaetes species belonging to 14 genera and 4 families. Naididae was represented by 8 spp.; Tubuficidae 8 spp.; Lumbriculidae 2 spp. and Lumbricidae 1 spp. Tubificid worms formed about 73% of the total count while Naididae formed 15%, Lumbriculidae 8% and Lumbricidae 4%.Among Tubificidae, Limnodrilus was the most abundant genus composed about 35% of L. hoffmeisteri; 11.5% L. claparedianus; 8% L. profundicola and 4.7% L. maumeensis, followed by Tubifex tubifex 23%. Other species were Branchuira sowerbyi formed 15%; 2.8 and 2 % for Peloscolex velutinus and Aulodrilus pigueti respectively. Naididae worms comprised 8 species including 32% of Dero digitata, 24% of Nais variabilis, 14% of Amphichaeta sp. and 11% of each of D.obtuse and Pristina longiseta. However, D. dorsalis represented only 7.5% of the total Naididae. Few individuals of B. sowerbyi and Lumbriculus variegates, with two regenerated parts at the posterior end were also detected in some samples. This case was considered a rare observation within the population of these worms in this particular area

    Simvastatin inhibits L-type Ca2+-channel activity through impairment of mitochondrial function

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    © The Author(s) 2019. Published by Oxford University Press on behalf of the Society of Toxicology. Plasma membrane ion channels and mitochondrial electron transport complexes (mETC) are recognized "off targets" for certain drugs. Simvastatin is one such drug, a lipophilic statin used to treat hypercholesterolemia, but which is also associated with adverse effects like myopathy and increased risk of glucose intolerance. Such myopathy is thought to arise through adverse actions of simvastatin on skeletal muscle mETC and mitochondrial respiration. In this study, we investigated whether the glucose intolerance associated with simvastatin is also mediated via adverse effects on mETC in pancreatic beta-cells because mitochondrial respiration underlies insulin secretion from these cells, an effect in part mediated by promotion of Ca2+ influx via opening of voltage-gated Ca2+ channels (VGCCs). We used murine pancreatic beta-cells to investigate these ideas. Mitochondrial membrane potential, oxygen consumption, and ATP-sensitive-K+- channel activity were monitored as markers of mETC activity, respiration, and cellular ATP/ADP ratio respectively; Ca2+ channel activity and Ca2+ influx were also measured. In intact beta-cells, simvastatin inhibited oxidative respiration (IC50 approximately 3 mM) and mETC (1 0.1 mM reversed activation of VGCCs by glucose but had no significant effect in the sugar s absence. The VGCC effects were mimicked by rotenone which also decreased respiration and ATP/ADP. This study demonstrates modulation of beta-cell VGCC activity by mitochondrial respiration and their sensitivity to mETC inhibitors. This reveals a novel outcome for the action of drugs like simvastatin for which mETC is an "off target"

    State-of-the-art three-dimensional analysis of soft tissue changes following Le Fort I maxillary advancement

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    We describe the comprehensive 3-dimensional analysis of facial changes after Le Fort I osteotomy and introduce a new tool for anthropometric analysis of the face. We studied the cone-beam computed tomograms of 33 patients taken one month before and 6-12 months after Le Fort I maxillary advancement with or without posterior vertical impaction. Use of a generic facial mesh for dense correspondence analysis of changes in the soft tissue showed a mean (SD) anteroposterior advancement of the maxilla of 5.9 (1.7) mm, and mean (SD) minimal anterior and posterior vertical maxillary impaction of 0.1 (1.7) mm and 0.6 (1.45) mm, respectively. It also showed distinctive forward and marked lateral expansion around the upper lip and nose, and pronounced upward movement of the alar curvature and columella. The nose was widened and the nostrils advanced. There was minimal forward change at the base of the nose (subnasale and alar base) but a noticeable upward movement at the nasal tip. Changes at the cheeks were minimal. Analysis showed widening of the midface and upper lip which, to our knowledge, has not been reported before. The nostrils were compressed and widened, and the lower lip shortened. Changes at the chin and lower lip were secondary to the limited maxillary impaction

    The effect of 980 nm and 1480 nm pumping on the performance of newly Hafnium Bismuth Erbium-doped fiber amplifier

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    An experimental study on the comparison of optical amplifying performance between 980 nm and 1480 nm pumping for the newly Hafnium Bismuth Erbium co-doped fiber (HB-DF) has been presented. A short length of 1-meter HB-EDF was used as the gain medium of the optical amplifier. 1480 nm pumping is found to provide higher attainable gain and lower noise figure compared to 980 nm pumping. At 1480 nm pumping, the average small signal gain for HB-EDFA in the single pass configuration has improved by 13.4 dB in the C-band region range from 1525 nm to 1565 nm. In the double-pass configuration, a maximum small signal gain of 36.6 dB was achieved at the wavelength of 1560 nm, this is 11.6 dB higher compared to the HB-EDFA with 980 nm pumping. The double pass HB-EDFA with 1480 nm pumping has exhibited a reduction of average noise figure by 23.4% and 29.8% for-30 dBm and-10 dBm of input signal power respectively in the C- and L-band region

    From Arabic Alphabets to Two Dimension Shapes in Kufic Calligraphy Style Using Grid Board Catalog

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    The Kufic font takes its name from the location in which the font was created around the end of the seventh century, Kufa, Iraq.  Kufic was the principal script used to replicate the Qur'ans until approximately the eleventh century. Depending upon where a character is located in a word, the character may be represented differently.  Given this location-specific representation, the Arabic characters uses in script are expanded to 116 shapes.  A character can have an isolated shape, a joined shape, a left joined shape and a right joined shape. The goal of this study is to convert Arabic script to a two-dimensional shape in Kufic calligraphy style that has regular geometric components (lines, circles, curves, arcs, etc.) by using a grid board catalog. The converting process represents a method of learning electronically as well as production for all Arabic alphabets in aesthetic shapes. The proposed grid board produces all possible shapes of any letter in Arabic alphabets.  Some alphabets are shared by sub shapes and are overlapped in the grid board in order to visualize them as groups of similar characters. The position of a letter in the grid board, the letter dimension itself (width and height) and the position of letters in Arabic words were required to convert the characters. The results showed that the proposed grid is a powerful and influential tool that can be used to learn the Kufic font style with a simple, easy and effective method when contrasted to the classical method

    Effect of heat treatment on the corrosion behaviour of LM6 in sulphuric acid and sodium hydroxide

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    Sulphuric acid (H2SO4) and sodium hydroxide (NaOH) are the main solutions used in water treatment stations to adjust the potential of hydrogen (PH). Pumps used in such stations must bear acidic and alkaline mediums. Pump parts such as impellers and casings could be made by aluminium silicon alloy (LM6) due to their cast-ability and corrosion resistance. In this paper, the corrosion behaviour of LM6 in acidic and alkaline solutions was investigated. The corrosion test samples of LM6 were prepared using a carbon dioxide sand casting mould. Test samples subjected to solution heat treatment. A corrosion test was conducted using the weight-loss method by immersing the samples in H2SO4 and NaOH. Resulted showed that the LM6 was more corroded in the alkali than in acid. Cumulative weight loss of non-heat-treated LM6 in H2SO4 was 11.23 mg/cm2 while in NaOH was 177 mg/cm2. Cumulative weight loss of heat-treated LM6 in H2SO4 was 8.44 mg/cm2 while in NaOH was 192 mg/cm2. The corrosion rate of non-heat-treated LM6 in H2SO4 was 78 MPY while heat-treated LM6 was 56 MPY. Concluded that LM6 is more corroded in NaOHthan in H2SO4 and the heat-treated LM6 was more corrosion resistance than the non-heat-treated one
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