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1.
Many prediction guidelines exist in facial approximation for determining the soft-tissue features of the face, and the reliability of each is generally unknown. This study examines four published and commonly used soft-tissue prediction guidelines for estimating nose projection, two of which also estimate the position of the pronasale. The methods tested are those described by: 1) Gerasimov ([1971] The Face Finder; London: Hutchinson & Co.), using the distal third of the nasal bones and the nasal spine; 2) Krogman ([1962] The Human Skeleton in Forensic Medicine; Springfield: Charles C. Thomas), using the average soft-tissue depth at midphiltrum, plus three times the length of the nasal spine (and a variation of this technique: plus three times the distance of the tip of the nasal spine from the nasal aperture); 3) Prokopec and Ubelaker ([2002] Forensic Sci Commun 4:1-4), using the reflected profile line of the nasal aperture; and 4) George ([1987] J Forensic Sci 32:1305-1330), using a variation of the Goode method. Four identical hard-tissue tracings were made of 59 adult lateral head cephlograms (29 males, mean age 24, SD 10 years; 30 females, mean age 23, SD 5 years) on separate sheets of tracing paper. One soft-tissue tracing was also made for each radiograph. All tracings were marked with three identical reference points. Soft-tissue tracings were isolated from one of us (C.N.S.), who attempted under blind conditions to predict pronasale position and nose projection on the hard-tissue tracings, using the soft-tissue prediction guides above. Actual soft-tissue tracings were then compared to each of the predicted tracings, and differences in projection/pronasale position were measured. Results indicate that for nose projection, methods 3 and 4 performed well, while methods 1 and 2 performed poorly. Features which are most related to nose projection/pronasale are described in this paper, as are regression equations generated from these variables that predict pronasale/nose projection better than the traditional methods mentioned above. The results of this study are significant because they: 1) indicate that the popular facial approximation methods used to build the nose are inaccurate and produce incorrect nose anatomy; and 2) indicate that the new pronasale prediction methods developed here appear to have less error than traditional methods. 相似文献
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Barbora Vozarova Jack Wang Christian Weyer P. Antonio Tataranni 《Obesity (Silver Spring, Md.)》2001,9(3):229-232
Objective: To compare two software versions provided by Lunar Co. for assessment of body composition analysis by DXA. Research Methods and Procedures: Soft‐tissue phantoms for lean tissue (water) and fat tissue (methanol) were repeatedly scanned using DXA machines (DPX‐L; Lunar Co., Madison, WI) and analyzed using software version 1.33 and the updated year 2000‐compatible version 1.35. For the intersoftware comparison, the phantoms were scanned 10 times (each scan was analyzed once) with both software versions using all three scanning modes (slow, medium, and fast) for a total of 60 scans and analyses. For the intermachine comparison, the same phantoms were scanned three times (each scan was analyzed once) with a second machine from the same manufacturer using all three scanning modes and version 1.35 only. Percentage of fat was the variable of interest. Results: For version 1.33, fat was 9.9 ± 0.4%, 10.0 ± 0.5%, and 11.0 ± 0.5% (mean ± SD) for the lean‐tissue phantom and 50.8 ± 0.3%, 50.9 ± 0.5%, and 51.1 ± 0.6% for the fat‐tissue phantom using the slow, medium, and fast scanning modes, respectively. For version 1.35, the respective fat values were 9.8 ± 0.7%, 9.9 ± 0.4%, and 10.3 ± 0.7%, and 50.6 ± 0.5%, 50.9 ± 0.6%, and 50.8 ± 0.8%, respectively. For the lean‐tissue phantom, the estimation of percentage of fat was significantly (p < 0.05) affected by scanning mode but not by software version. For the fat‐tissue phantom, the estimation of percentage of fat was not affected by either scanning mode or software version. The use of version 1.35 did not effect intermachine variability. Discussion: Versions 1.33 and 1.35 of the Lunar body composition software appear to be comparable. Soft‐tissue phantoms, such as the ones described in this paper, may be useful in monitoring the reproducibility of body composition analyses within and between DXA machines, particularly in longitudinal studies. 相似文献
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基因预测是指预测DNA序列中编码蛋白质的部分。随着多数生物基因组的测序工作的完成 ,基因预测更显得尤为重要。基因预测主要包括两种方法 ,首先是同源方法 ,也称为“外在方法” ,其次是基因预测方法或称为“内在方法”。主要对隐马尔可夫模型、傅立叶变换、动态规划等几种“外在方法”进行介绍。 相似文献
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Li Shen Hany Farid Mark A. McPeek 《Evolution; international journal of organic evolution》2009,63(4):1003-1016
Quantifying morphological shape is a fundamental issue in evolutionary biology. Recent technological advances (e.g., confocal microscopy, laser scanning, computer tomography) have made the capture of detailed three-dimensional (3D) morphological structure easy and cost-effective. In this article, we develop a 3D analytic framework (SPHARM—spherical harmonics) for modeling the shapes of complex morphological structures from continuous surface maps that can be produced by these technologies. Because the traditional SPHARM methodology has limitations in several of its processing steps, we present new algorithms for two SPHARM processing steps: spherical parameterization and SPHARM registration. These new algorithms allow for the numerical characterization of a much larger class of 3D models. We demonstrate the effectiveness of the method by applying it to modeling the cerci of Enallagma damselflies. 相似文献
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William I. Ausich Christoph Bartels Thomas W. Kammer 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2013,46(3):416-420
Fossilized tube feet are described on Codiacrinus schultzei Follmann from the Lower Devonian Hunsrück Slate of Germany. This is the first definitive proof of tube feet on any fossil crinoid. Three lightly pyritized, flattened tube feet are preserved in a single interray of this cladid crinoid. The tube feet were at least 7 mm long. Their preservation is very similar to the tube feet reported previously from a Hunsrück ophiuroid, except that the Codiacrinus tube feet have small papillae, similar to living crinoids. 相似文献
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Si Chen Hangdi Lou Liang Guo Yi Liu 《Computer methods in biomechanics and biomedical engineering》2013,16(3):255-261
Prediction of soft tissue aesthetics is important for achieving an optimal outcome in orthodontic treatment planning. Previously, applicable procedures were mainly restricted to 2-D profile prediction. In this study, a generic 3-D finite element (FE) model of the craniofacial soft and hard tissue was constructed, and individualisation of the generic model based on cone beam CT data and mathematical transformation was investigated. The result indicated that patient-specific 3-D facial FE model including different layers of soft tissue could be obtained through mathematical model transformation. Average deviation between the transformed model and the real reconstructed one was 0.47 ± 0.77 mm and 0.75 ± 0.84 mm in soft and hard tissue, respectively. With boundary condition defined according to treatment plan, such FE model could be used to predict the result of orthodontic treatment on facial soft tissue. 相似文献
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F. Marin K. Ben Mansour F. Demeter P. Frey 《Computer methods in biomechanics and biomedical engineering》2015,18(13):1988-1989
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Comparative modeling is presently the most accurate method of protein structure prediction. Previous experiments have shown the selection of the correct template to be of paramount importance to the quality of the final model. We have derived a set of 732 targets for which a choice of ten or more templates exist with 30-80% sequence identity and used this set to compare a number of possible methods for template selection: BLAST, PSI-BLAST, profile-profile alignment, HHpred HMM-HMM comparison, global sequence alignment, and the use of a model quality assessment program (MQAP). In addition, we have investigated the question of whether any structurally defined subset of the sequence could be used to predict template quality better than overall sequence similarity. We find that template selection by BLAST is sufficient in 75% of cases but that there are examples in which improvement (global RMSD 0.5 A or more) could be made. No significant improvement is found for any of the more sophisticated sequence-based methods of template selection at high sequence identities. A subset of 118 targets extending to the lowest levels of sequence similarity was examined and the HHpred and MQAP methods were found to improve ranking when available templates had 35-40% maximum sequence identity. Structurally defined subsets in general are found to be less discriminative than overall sequence similarity, with the coil residue subset performing equivalently to sequence similarity. Finally, we demonstrate that if models are built and model quality is assessed in combination with the sequence-template sequence similarity that a extra 7% of \"best\" models can be found. 相似文献
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《Biotechnic & histochemistry》2013,88(4):242-254
AbstractThe success of dental implant treatment depends on the healing of both hard and soft tissues. While osseointegration provides initial success, the biological seal of the peri-implant soft tissue is crucial for maintaining the long term success of implants. Most studies of the biological seal of peri-implant tissues are based on animal or monolayer cell culture models. To understand the mechanisms of soft tissue attachment and the factors affecting the integrity of the soft tissue around the implants, it is essential to obtain good quality histological sections for microscopic examination. The nature of the specimens, however, which consist of both metal implant and soft peri-implant tissues, poses difficulties in preparing the specimens for histomorphometric analysis of the implant-soft tissue interface. We review various methods that have been used for the implant-tissue interface investigation with particular focus on the soft tissue. The different methods are classified and the advantages and limitations of the different techniques are highlighted. 相似文献
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Bharat Rekhi;Xiaohua Qian;Henryk A. Domanski;Jerzy Klijanienko;Andrew Field; 《Cytopathology》2024,35(1):30-47
Fine needle aspiration biopsy (FNAB) is a diagnostic modality for the evaluation of suspicious soft tissue masses. Despite its reasonable sensitivity, specificity and positive predictive value in differentiating benign from malignant neoplasms, the exact subtyping of the primary soft tissue tumours can be challenging. Certain tumours constitute “pitfalls” and add to the diagnostic challenge. This review provides a detailed account of the diagnostic challenges in soft tissue cytopathology, including pitfalls and, more importantly, the ways to overcome these challenges by integrating clinical details, key cytomorphological features and judicious application of ancillary techniques. 相似文献
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Georgy Derevyanko Sergei Grudinin 《Acta Crystallographica. Section D, Structural Biology》2014,70(8):2069-2084
HermiteFit, a novel algorithm for fitting a protein structure into a low‐resolution electron‐density map, is presented. The algorithm accelerates the rotation of the Fourier image of the electron density by using three‐dimensional orthogonal Hermite functions. As part of the new method, an algorithm for the rotation of the density in the Hermite basis and an algorithm for the conversion of the expansion coefficients into the Fourier basis are presented. HermiteFit was implemented using the cross‐correlation or the Laplacian‐filtered cross‐correlation as the fitting criterion. It is demonstrated that in the Hermite basis the Laplacian filter has a particularly simple form. To assess the quality of density encoding in the Hermite basis, an analytical way of computing the crystallographic R factor is presented. Finally, the algorithm is validated using two examples and its efficiency is compared with two widely used fitting methods, ADP_EM and colores from the Situs package. HermiteFit will be made available at http://nano‐d.inrialpes.fr/software/HermiteFit or upon request from the authors. 相似文献
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A key feature of the pigment melanin is its high binding affinity for trace metal ions. In modern vertebrates trace metals associated with melanosomes, melanin‐rich organelles, can show tissue‐specific and taxon‐specific distribution patterns. Such signals preserve in fossil melanosomes, informing on the anatomy and phylogenetic affinities of fossil vertebrates. Fossil and modern melanosomes, however, often differ in trace metal chemistry; in particular, melanosomes from fossil vertebrate eyes are depleted in Zn and enriched in Cu relative to their extant counterparts. Whether these chemical differences are biological or taphonomic in origin is unknown, limiting our ability to use melanosome trace metal chemistry to test palaeobiological hypotheses. Here, we use maturation experiments on eye melanosomes from extant vertebrates and synchrotron rapid scan‐x‐ray fluorescence analysis to show that thermal maturation can dramatically alter melanosome trace element chemistry. In particular, maturation of melanosomes in Cu‐rich solutions results in significant depletion of Zn, probably due to low pH and competition effects with Cu. These results confirm fossil melanosome chemistry is susceptible to alteration due to variations in local chemical conditions during diagenesis. Maturation experiments can provide essential data on melanosome chemical taphonomy required for accurate interpretations of preserved chemical signatures in fossils. 相似文献
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The recent expansion of a variety of morphometric tools has brought about a revolution in the comparison of morphology in the context of the size and shape in various fields including entomology. First, an overview of the theoretical issues of geometric morphometrics is presented with a caution about the usage of traditional morphometric measurements. Second, focus is then placed on two broad approaches as tools for geometric morphometrics; that is, the landmark‐based and the outline‐based approaches. A brief outline of the two methodologies is provided with some important cautions. The increasing trend of entomological studies in using the procedures of geometric morphometrics is then summarized. Finally, information is provided on useful toolkits such as computer software as well as codes and packages of the R statistical software that could be used in geometric morphometrics. 相似文献
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Julio A. Kovacs Pablo Chacn Yao Cong Essam Metwally Willy Wriggers 《Acta Crystallographica. Section D, Structural Biology》2003,59(8):1371-1376
The `fast rotational matching' method (an approach to find the three rotational degrees of freedom in matching problems using just one three‐dimensional FFT) is extended to the full six‐dimensional (rotation and translation) matching scenario between two three‐dimensional objects. By recasting this problem into a formulation involving five angles and just one translational parameter, it was possible to accelerate, by means of fast Fourier transforms, five of the six degrees of freedom of the problem. This method was successfully applied to the docking of atomic structures of components into three‐dimensional low‐resolution density maps. Timing comparisons performed with our method and with `fast translational matching' (the standard way to accelerate the translational parameters utilizing fast Fourier transforms) demonstrates that the performance gain can reach several orders of magnitude, especially for large map sizes. This gain can be particularly advantageous for spherical‐ and toroidal‐shaped maps, since the scanning range of the translational parameter would be significantly constrained in these cases. The method can also be harnessed to the complementary surface (or `exterior docking') problem and to pattern recognition in image processing. 相似文献
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Kurl E. Jamora Reno Eufemon P. Cereno Elrick T. Inocencio Vicente Francisco R. Hizon 《Reports of Practical Oncology and Radiotherapy》2022,27(1):182
Dermatofibrosarcoma protuberans (DFSP) is a rare spindle cell tumor, comprising less than 0.1% of all malignant neoplasms. The trunk is the most commonly affected area, followed by the extremities and the head and neck. Of the latter cases, involvement of the periorbital area has been infrequently reported. Surgery is the cornerstone of treatment but is associated with a high rate of recurrence if margins remain close or positive. This rate has been shown to be considerably decreased by the use of adjuvant radiotherapy. However, most reported cases utilize external beam radiation therapy (EBRT ) in the treatment of DFSP, including those with primary periorbital locations. We report a case of a 40-year-old male, presenting with a small nodule on the right upper eyelid, diagnosed as DFSP with positive margins post-surgery and treated with adjuvant customized surface mould high-dose-rate (HDR) brachytherapy in a low-resource setting. 相似文献
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已知miR-21在多种生物学过程中发挥重要的调控作用,然而有关鸡miR-21功能的研究尚未见报道。为了解鸡miR 21的潜在生物学功能,采用qRT-PCR检测了固始鸡5个发育阶段、15种组织中miR-21的表达情况。同时,利用Pictar和TargetScan算法预测了miR-21的靶基因并对预测的靶基因进行了Gene Ontology分析和通路分析。结果显示,miR-21的表达具有明显的时序特征,除14胚龄鸡的小脑和腺胃外,胚胎期各组织中miR-21的表达水平均显著低于出壳后对应组织的表达水平;出壳后鸡的下丘脑、大脑、小脑、小肠、肝脏、胸肌和肾脏等组织中miR-21的表达水平随发育进程均显著上调。生物信息学分析显示,预测的miR-21的靶基因在基因表达调控、大分子代谢调控、转录调控、细胞代谢调控、细胞衰老和增殖、呼吸系统发育、骨骼发育、心脏发育和神经系统发育等广泛的生物学过程中显著富集。总之,鸡miR-21为广泛性时序表达miRNA,可能参与鸡出壳后诸多器官发育相关的生物学过程的调控。 相似文献