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Corals nucleate and grow aragonite crystals, organizing them into intricate skeletal structures that ultimately build the world’s coral reefs. Crystallography and chemistry have profound influence on the material properties of these skeletal building blocks, yet gaps remain in our knowledge about coral aragonite on the atomic scale. Across a broad diversity of shallow-water and deep-sea scleractinian corals from vastly different environments, coral aragonites are remarkably similar to one another, confirming that corals exert control on the carbonate chemistry of the calcifying space relative to the surrounding seawater. Nuances in coral aragonite structures relate most closely to trace element chemistry and aragonite saturation state, suggesting the primary controls on aragonite structure are ionic strength and trace element chemistry, with growth rate playing a secondary role. We also show how coral aragonites are crystallographically indistinguishable from synthetic abiogenic aragonite analogs precipitated from seawater under conditions mimicking coral calcifying fluid. In contrast, coral aragonites are distinct from geologically formed aragonites, a synthetic aragonite precipitated from a freshwater solution, and mollusk aragonites. Crystallographic signatures have future applications in understanding the material properties of coral aragonite and predicting the persistence of coral reefs in a rapidly changing ocean.

Enigmatic rod-like skeletal structures that support compliant membranes (patagia) in aerial mammals have been often considered as neomorphic elements or as evolutionary novelties, and their origin has remained poorly understood. A potential source of skeletal plasticity and, probably, of morphofunctional innovations are sesamoids, which were recently demonstrated to have a common cellular origin with bone eminences. In this review, I compile information regarding anatomy, evolution, and development of rod-like skeletal elements in extant gliding and flying mammals and propose a working hypothesis on the origin of these structures. Rod-like skeletal elements, namely, the calcar in bats (Chiroptera), the unciform element in Anomaluridae (Rodentia), and the styliform cartilage in Pteromyini (Rodentia: Sciuridae), would derive from sesamoids, which, in turn, would have the same origin as eminences of long bones (or bones with a long-bone-like growth), i.e., calcaneus, ulna, and pisiform, respectively. Rod-like skeletal elements exhibit several features of sesamoids. However, further developmental data are needed to confirm this hypothesis, particularly whether these structures share a cellular origin and molecular developmental pathways with sesamoids and bone eminences. If this hypothesis were supported, a new role for sesamoids in generating morphofunctional innovations in mammals and, potentially, in other aerial amniotes, would be recognized. Rod-like skeletal elements, which are key in the evolution of aerial locomotion, might constitute an example of pre-existing traits that acquire novel functions through relatively little developmental plasticity.

CT-guided percutaneous drainage is a safe and effective procedure that allows minimally invasive treatment of abdominopelvic abscesses and fluid collections. This technique has become an alternative for surgery with lower morbility and mortality rates. In this pictorial essay, we aim at providing an overview of the technical approaches, the main clinical indications and complications of CT-guided percutaneous drainage, in order to provide a practical guide for interventional radiologists, with a review of the recent literature. The focus will be the CT-guidance, preferred when the interposition of viscera, vascular and skeletal structures, counteracts the ultrasound guidance.

Introduction Geometric morphometrics (GM) is an advanced landmark-based quantitative method used to study biological shape and form. Historically, GM has been limited to non-biomedical fields such as comparative biology; however, this technique confers advantages over traditional cephalometric methods, warranting a review of current applications of GM to human craniofacial disorders. Methods The RISmed package was used to extract metadata associated with PubMed publications referencing GM analysis techniques in craniofacial and reconstructive surgery. PubMed search terms included "geometric AND morphometric AND craniofacial;" and "geometric AND morphometric AND reconstructive surgery." Duplicate search results were eliminated. Results Search yielded 139 studies between 2005 and 2020, of which 27 met inclusion criteria. Human craniofacial studies constituted 2% of all queried GM studies. Among these, cleft lip and palate were the most commonly studied craniofacial conditions (7 studies, 26%), followed by sagittal craniosynostosis (4 studies, 15%). Seventeen studies (63%) used GM to assess skeletal structures, seven studies (26%) examined both skeletal and soft tissues, and three studies (11%) analyzed soft tissues only. Eleven studies (40.1%) employed a GM approach to evaluate postoperative changes in craniofacial morphology. Two studies (7%) systematically compared GM analysis with conventional shape measurements. Conclusion The ability to study shape while controlling for variability in structure size and imaging technique make GM a promising tool for understanding growth patterns in complex craniofacial diseases. Furthermore, GM overcomes many limitations of traditional cephalometric techniques, and hence may claim an expanded role in the study of human craniofacial disorders in clinical and research settings.

Jaya algorithm is a simple and efficient population-based metaheuristic algorithm. Besides its simplicity, it has free from any algorithm-specific parameters. Although it has these advantages, the Jaya algorithm suffers from some shortcomings including unwanted premature convergence and the possibility of being trapped in local minima due to insufficient population diversity. To alleviate these handicaps, this paper proposes an Improved Shuffled based Jaya (IS-Jaya) algorithm. The proposed optimization method uses the concept of shuffling process to gain superior exploration capability in the search mechanism. A mechanism that causes to escape from local minima is also incorporated into the original Jaya algorithm. The efficiency of the IS-Jaya algorithm is tested on discrete optimization problems and compared to those of Jaya algorithm, self-adaptive multi-population-based Jaya (SAMP-Jaya), and some other state-of-art optimization methods. Optimization results show that the proposed optimization method can be an effective tool for solving discrete size optimization of skeletal structures.

NEW FINDINGS What is the topic of this review? Mechanisms regulating bone length and skeletal proportions What advances does it highlight? The study of differential bone length between leg and finger bones, metatarsals of the Egyptian jerboa and genomic analysis of giraffes. ABSTRACT Among mammalian species, skeletal structures vary greatly in size and shape, leading to a dramatic variety of body sizes and proportions. How different bones grow to different lengths, whether among different species, different individuals of the same species, or even in different anatomical parts of our the body, has always been a fascinating subject of research in biology and physiology. In the current review, we focus on some of the recent advances in the field and discuss how these provided important new insights into the mechanisms regulating bone length and skeletal proportions.

Objectives To evaluate alveolar bone change in relation to root position change after maxillary incisor retraction via cone-beam computed tomography (CBCT) using stable skeletal structures as a reference. Materials and Methods A total of 17 subjects (age 24.7 ± 4.4 years) who required retraction of the maxillary incisors were included. Labial and palatal alveolar bone changes and root change were assessed from preretraction and 3 months postretraction CBCT images. The reference planes were based on stable skeletal structures. The Kruskal-Wallis test and Wilcoxon signed-rank test were used to compare changes within and between groups, as appropriate. Spearman rank correlations were used to identify the parameters that correlated with alveolar bone change. The significance level was set at .05. Results The labial alveolar bone change after maxillary incisor retraction was statistically significant (P < .05), and the bone remodeling/tooth movement (B/T) ratio was 1:1. However, the palatal bone remained unchanged (P > .05). The change in inclination was significantly related to labial alveolar bone change. Conclusions Using stable skeletal structures as a reference, the change in labial alveolar bone followed tooth movement in an almost 1:1 B/T ratio. Palatal alveolar bone did not remodel following maxillary incisor retraction. The change in inclination was associated with alveolar bone change.

This article proposes a new damage detection method using Modal Test Analysis Model and artificial neural networks. A challenge in damage detection problems is lack of measured degrees of freedom, as well as limitations of attached sensors. Modal Test Analysis Model has been used in order to estimate unmeasured degrees of freedom. An experimental cantilever beam was used to show Modal Test Analysis Model’s efficiency in estimation of unmeasured mode shapes. To solve the inverse problem of damage detection, mode shapes estimated by Modal Test Analysis Model were used as inputs, and characteristics of the damage served as outputs of the artificial neural network. The sensitivity analysis carried out for each example showing the performance of artificial neural network after mode shape expansion was efficiently improved. Three numerical examples for plane and space truss structures are considered, in order to verify effectiveness of the proposed method. Results demonstrate a high accuracy of Modal Test Analysis Model and artificial neural network for structural damage detection.

Postmortem computer tomography (CT) came into practice of forensic medicine in the 1990s and has later been complemented with magnetic resonance imaging (MRI). A pioneer virtual autopsy was conducted in Germany in 1983. In the Czech Republic, this examination was first performed in 1993.A typical examination requires about 30 min, with the most resource-demanding stage being the image data rendering. CT was shown to better capture skeletal structures, while MRI contrasting is superior in terms of visualising soft tissues. In the Czech Republic, CT-based virtopsy is legislated mandatory to document deaths inflicted by gunshots, road traffic and aviation accidents, high falls, occupational and explosive-related injuries, thermal and mechanical traumas, strangulation, drowning as well as to examine unidentified or decomposing bodies, deceased children and adolescents aged under 18.CT scanning prior to conventional autopsy provides a forensic expert with guidance to reveal pathologies non-invasively in particular regions that are difficult to dissect or access. The advantage of virtopsy is the objective acquisition of data that can be re-examined, reinterpreted or juxtaposed with the results of conventional autopsy and easily recovered for possible further expertise.

Vibration-based structural damage identification through optimization techniques has become an interesting research topic in recent years. Dynamic characteristics such as frequencies and mode shapes are used to construct the objective function. The objective functions based on only frequencies are not very sensitive to damage in large structures. However, objective functions based on both mode shapes and frequencies are very effective. In real measurement condition, the number of installed sensors is limited, and there are no economic reasons for measuring the mode shapes at all degrees of freedom. In this kind of circumstances, mode expansion methods are used to address the incompleteness of mode shapes. In this article, the system equivalent reduction and expansion process is applied to determine the unmeasured mode shapes. Two experimental examples including a cantilever beam and a truss tower are investigated to show system equivalent reduction and expansion process’ efficiency in estimating unmeasured mode shapes. The results show that the technique used for expansion is influential. Damage identification is formulated as an optimization problem, and the residual force vector based on expanded mode shapes is considered as an objective function. In order to minimize the objective function, grey wolf optimization and Harris hawks optimization are used. Numerical studies on a 56-bar dome space truss and experimental validation on a steel frame are performed to demonstrate the efficiency of the developed approach. Both numerical and experimental results indicate that the combination of the grey wolf optimization and expanded mode shapes with system equivalent reduction and expansion process can provide a reliable approach for determining the severities and locations of damage of skeletal structures when it compares with those obtained by Harris hawks optimization.

Objectives: Pronation distortion syndrome is one of the common physical deformities, that causes distortions in the skeletal structures of the feet. The current study aimed to determine the effects of 12 weeks of systematic and functional corrective exercises on the body posture of students with pronation distortion syndrome. Methods: In this quasi-experimental study, 30 volunteers suffering from pronation distortion syndrome were selected. Then, they were randomly divided into two 15-member groups, i.e. the experimental and the control groups. The experimental group practiced systematic and functional corrective exercises for 12 weeks (three sessions a week, each lasting an hour), while the control group did not receive any exercises. Before and after the exercises, the students were evaluated using the Functional Movement Screen (FMS) screening test as well as body posture tests, including flat feet, pronation angle of ankle joint, knock-knee (bow-leggedness or genu valgum), and lumbar lordosis (swayback). The obtained data were analyzed using the dependent and independent t-tests (P

This paper aims to account for the idiosyncratic properties of the Contrastive Stripping Construction (CSC) in English. The main issues on this construction are how to generate its 4 possible skeletal structures and get the right contrastive reading from them. Rejecting the Movement-Ellipsis approaches facing theoretical and/or empirical problems, we propose a constructionbased analysis of the CSC which interacts the English CSC-cx rule with various lexical information of the lexemes such as and and but. This enables us to generate the 4 skeletal structures of the CSC and assign an appropriate contrastive reading to them.

Introduction. The Herbst device is widely used for correction of class II malocclusions; however, most of the researches carried out on the Herbst appliance in literature do not take into account patients with a different mandibular divergence. The aim of this study was to investigate the effects of Herbst on dental and skeletal structures and to evaluate possible influence of vertical facial growth patterns.Methods. A retrospective study was conducted on lateral cephalograms of 75 growing patients (mean age: 9.9 ± 1.9 years) with class II malocclusion treated with Herbst. Subjects were divided into 3 groups using the mandibular divergence index (SN and GoMe angle). Cephalometric parameters were evaluated using the modified SO (sagittal occlusion) Pancherz’s analysis. A statistical analysis was conducted to evaluate differences among groups using ANOVA.Results. Our study showed differences in response to treatment depending on patient’s facial vertical growth pattern. Cranial base angle and mandibular rotation were significantly different (p<0.05) between hypodivergent patients and normodivergent patients and between hypodivergent and hyperdivergent subjects.Conclusion. Hypodivergent patients increased their mandibular divergence during treatment to a greater extent than normodivergents; moreover, hyperdivergent patients exhibited a decreased mandibular divergence at the end of the treatment.

Bone plays an increasingly critical role in human health and disease. More noninvasive multi-scale imaging techniques are urgently required for investigations on the substructures and biological functions of bones. Our results firstly revealed that SWIR QDs prepared by us acted as a bone-specific imaging contrast to achieve real-time observation of bone structures both in vivo and ex vivo. The major bone structures of both Balb/C nude mice and Balb/C mice including their skull, spine, pelvis, limbs, and sternum could be rapidly and gradually identified via blood circulation after QD injection in vivo. More importantly, the binding capability of our QDs mainly depended on the biological activities of bone tissues, suggesting that our technique is suitable for in vivo live imaging. In addition, the cell imaging results suggested that the potential mechanism of our bone imaging could be ascribed to the highly specific interaction between QDs and MC3T3-E1 cells. In a word, the skeletal structures and biological activities of bones are anticipated to be observed and monitored with this QD-guided SWIR imaging strategy, respectively. This radiation-free QD-guided SWIR live imaging of bone can add new insights into a comprehensive study of bones in vivo and provide a basis for early diagnosis of bone diseases.

Class II malocclusion is ranked as the most prevalent type of glitches that require orthodontic treatment. It can be managed via several lines of treatment the choice between which must be dependent on each case requirements. Maxillary molars distalization is one of the most popular non extraction alternatives for class II treatment. There are many distalization appliances listed in the literature which can be categorized to either compliance or non-compliance types. Compliance distalization appliances include head gear, Cetlin appliance, Wilson Biometric Distalizing Arch and Carrieredistalizer. Lack of patient cooperation comprises a major problem of these appliances and always leads to lengthy treatment in addition to less than ideal results. Non-compliance distalization appliances for class II treatment include NiTi coil springs, Pendulum appliance, Distal jet, Keles slider and Fast Back appliance. Most of these appliances gain anchorage from dental structures or Nance palatal holding arch. This always leads to adverse effects as consequences of anchorage loss represented in mesial movement of premolars and anterior teeth, increased overjet and palatal tissue irritation by the non-hygienic Nance acrylic button. Distalization appliances that involve a stable skeletally anchored modules have recently gained large popularity to avoid anchorage loss. It implies insertion of temporary anchorage devices (TADs) in different location of skeletal structures to receive and resist the reactive forces of distalization. Implant, miniplates and miniscrews are the main TADs used for orthodontic purposes. However, implants and miniplates are not widely used as they are expensive and require special surgical intervention. Miniscerws are the most common type of TADs due to their easy insertion, reasonable cost and many head designs that accommodate different orthodontic uses.

For the first time the role of rhyncholites in the process of epibiota has been figured out. Serpulidae inlay is detected in 39 rhyncholites of 979 specimens, representing 4% of the all studied material. This fact demonstrates that rhyncholites were used extremely rarely by encrusting species as a substrate. No other epibionts were found. Polychaetes were found in the genus Hadrocheilus (87%) and in the genus Akidocheilus. Size of the inlaid rhyncholites ranges from 7 to 23 mm. Serpulidae cover usually only the ventral side of rhyncholites, herewith, at 48,7% of the samples epibionts with different degrees of intensity are developed throughout the ventral surface, at 30,7% of the samples they are observed only on the ventral side of the hood and at 20,6% serpulidae are present only on the ventral surface of the arm. At four exemplars of the genus Hadrocheilus (10 % of the total amount) polychaetes are developed on the dorsal surface, but they are always and usually very wide developed on the ventral side of rhyncholites. No samples were found in which serpulidae were found only on the dorsal surface. Among the remains of polychaete worms, large and small tubes were identified and described. The presence of serpulidae on the handle of rhyncholites, that during the life of the cephalopod mollusk was located in a horny jaw, is a clear indication of the settlement’s epibionts on isolated skeletal structures of the already dead cephalopod. Cases when serpulidae are observed only on the ventral side of the hood in representatives of the genus Akidocheilus, suggest that planktonic trochophore – larvae of polychaetes can settle on the inner surface of the mandible of living ammonoids, where they turned into an adult worm. At the same time, polychaetes gained access not only to traditional prey, represented by various microscopic organisms, but also to additional food resources associated with the life activity of cephalopodas.

Recent efforts to reconstruct the phylogeny of brittle stars (ophiuroids) have shown the need for more objective and reproducible data collection methods than the traditional visual examination and verbal description of morphological characters. Complex skeletal structures may be better understood in three dimensions than in two dimensions obtained from techniques like scanning electron microscopy (SEM). We test this hypothesis using three types of three-dimensional tomographic imaging methods—lab-based micro-CT, X-ray microscopy and synchrotron-based tomography—to examine the morphology of ophiuroid arms, and compare them with two-dimensional data obtained from SEM. We describe the advantages and disadvantages of each instrument and set of parameters in terms of the ease and efficiency of data collection for morphometric analyses. We present new morphological observations obtained by digital sectioning of three-dimensional images that could not be achieved with SEM. Overall, our findings suggest that three-dimensional imaging has a high potential to address the gaps in knowledge of the internal ophiuroid skeleton, which will be pivotal to providing morphological characters that will aid in phylogenetic reconstructions.

This study concerns with the design optimization of steel skeletal structures thereby utilizing both a real-life specification provisions and ready steel profiles named hot-rolled I sections. For this purpose, the enhanced genetic algorithm methodology named EGAwMP is utilized as an optimization tool. The evolutionary search mechanism of EGAwMP is constituted on the basis of generational genetic algorithm (GGA). The exploration capacity of EGAwMP is improved in a way of dividing an entire population into sub-populations and using of a radial basis neural network for dynamically adjustment of EGAwMP’s genetic operator parameters. In order to improve the exploitation capability of EGAwMP, the proposed neural network implementation is also utilized for prediction of more accurate design variables associating with a new design strategy, design codes of which are based on the provisions of LRFD_AISC V3 specification. EGAwMP is applied to determine the real-life ready steel profiles for the optimal design of skeletal structures with 105, 200, 444, and 942 members. EGAwMP accomplishes to increase the quality degrees of optimum designations Furthermore, the importance of using the real-life steel profiles and design codes is also demonstrated. Consequently, EGAwMP is suggested as a design optimization tool for the real-life steel skeletal structures.

Automatic detection of a designated building area (DBA) is a research hotspot in the field of target detection using remote sensing images. Target detection is urgently needed for tasks such as illegal building monitoring, dynamic land use monitoring, antiterrorism efforts, and military reconnaissance. The existing detection methods generally have low efficiency and poor detection accuracy due to the large size and complexity of remote sensing scenes. To address the problems of the current detection methods, this paper presents a DBA detection method that uses hierarchical structural constraints in remote sensing images. Our method was conducted in two main stages. (1) During keypoint generation, we proposed a screening method based on structural pattern descriptors. The local pattern feature of the initial keypoints was described by a multilevel local pattern histogram (MLPH) feature; then, we used one-class support vector machine (OC-SVM) merely to screen those building attribute keypoints. (2) To match the screened keypoints, we proposed a reliable DBA detection method based on matching the local structural similarities of the screened keypoints. We achieved precise keypoint matching by calculating the similarities of the local skeletal structures in the neighboring areas around the roughly matched keypoints to achieve DBA detection. We tested the proposed method on building area sets of different types and at different time phases. The experimental results show that the proposed method is both highly accurate and computationally efficient.

Maxillary protraction with expansion is the recommended treatment modality for growing patients with cleft lip and palate. The aim of this study was to compare the displacement of the craniofacial structures using Facemask and Maxgym for protractiontherapy.A3-Dfiniteelementmodelconsistingof185620tetrahedralshapedelementsand49807nodeswascreated using CT scan of a patient with UCLP. F1, F2, F3 represent protraction forces used for Facemask and M1, M2, M3 represent protractionforcesusedforMaxgym.E1representsSlowMaxillaryExpansionforceandE2representsRapidMaxillaryExpansion force. Protraction forces were applied parallel to the occlusal plane on the buccal side of the first premolars. Expansion forces were also applied on the lingual side of the first premolars and the first molars. The displacement of 13 representative nodes of craniofacial structures analyzed and compared. The selected nodes of dental and skeletal structures were displaced in sagittal direction under all loading conditions. Only protraction or expansion force results in displacement of craniofacial structures. Protraction with expansion forces resulted in larger displacement. Maxgymforcesproducegreaterdisplacementthan Facemask under all loading conditions. Maxgym may be used as an alternative to Facemask to treat midfacial deficiency

We propose a new technique that evaluates the structures of car interiors by the following two algorithms, based on visual processing in the brain. (1) Medial axes reveal the imaginary skeletal structures within objects. (2) Saliency maps identify the areas attracting attention in visual scenes. Integration of these techniques revealed hidden axes characterizing the global structures of car dashboards, which are possibly more alluring than explicit features. Furthermore, the variety of such hidden axes across different cars/brands can be summarized in reduced dimensional spaces. Because features revealed by this technique are consistent with the framework of universal rules for aesthetic experiences (e.g., symmetry and perceptual problem solving), this could be useful to evaluate some aspects of aesthetic values quantitatively in car interiors.

The shape and arrangement of skeletal structures (spicules) in marine sponges are used in their taxonomic classification but shared spicule patterns often do not correspond to relationships postula...

Andosols are characterized by an abundance of black humic acids (HAs) belonging to Type A with a high content of aromatic carbon (C) in particular condensed aromatic C. Black HAs are also observed ...

Purpose Facial transplantation involves partial or total replacement of neuromuscular and skeletal structures of the face, head, and neck using donor tissues and is among the most extensive facial reconstructive procedures. This case report compares changes in speech production and articulator movement in a 44-year-old man from pretransplant to a 13-month posttransplant period. Method Speech production and articulator movement data were examined at 5 time points, once pretransplant and 4 times posttransplant (4, 7, 10, and 13 months), and compared to 4 healthy controls. A motion capture system was used to track jaw and vertical/horizontal lip movement during nonspeech and speech tasks. Speech intelligibility, jaw displacement, lip aperture, and movement variability were measured. Results Speech intelligibility varied across the study period and was restored to control status by 7 months posttransplant. Jaw displacement and lip aperture in the vertical plane significantly increased over time for nonspeech and speech tasks. Changes in horizontal lip movements over time were minimal. Jaw and lip movement variability fluctuated over time and was greater than the controls by 13 months posttransplant. Discussion Findings quantify changes in articulator movement and contributions to improved speech production following facial transplant. Changes reflect the adaptability of the speech motor system and are discussed in relation to pretransplant speech motor control patterns.

Roveacrinid crinoids from two upper Cenomanian localities of the Bohemian-Saxonian Cretaceous Basin are described. The well known Hoher Stein locality (Saxony) and the Předboj locality (Bohemia) provided rich collections of roveacrinids and other fauna. Biostratigraphy based on foraminifera and nannoplankton showed that Hoher Stein is somewhat older than Předboj (Rotalipora cushmani × Whiteinella archaeocretacea zones). Lebenharticrinus canaliculatus gen. et sp. nov. is described. The species Roveacrinus geinitzi Schneider dominates at Hoher Stein while R. alatus Douglas, R. communis Douglas, Lebenharticrinus canaliculatus gen. et sp. nov. and Styracocrinus peracutus (Peck) are much more rare. The Předboj site is dominated by the species R. alatus while R. communis and L. canaliculatus gen. et sp. nov. are rare and Styracocrinus peracutus and R. geinitzi are missing. In the large numbers of isolated brachials, most proximal ossicles of the species of Roveacrinus were identified. Special Osteocrinus-like, long, rod-shaped ossicles were also found and described, and tentatively considered as parts of arms of L. canaliculatus and S. peracutus. Skeletal structures were studied in all species, especially the canal system of dorsal cup parts in L. canaliculatus and S. peracutus. Mass occurrences of studied crinoids most probably reflect the enormously large offshore populations of crinoids, their adequately elevated landward transport and following death in shallow waters near the cliff.