scholarly journals Using micro-CT techniques to explore the role of sex and hair in the functional morphology of bumblebee (Bombus terrestris) ocelli

2018 ◽  
Author(s):  
David Wilby ◽  
Tobio Aarts ◽  
Pierre Tichit ◽  
Andrew Bodey ◽  
Christoph Rau ◽  
...  
Keyword(s):  
Bombus Terrestris ◽  
Visual Fields ◽  
Mating Strategies ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
3D Data ◽  
Computed Tomography Scans ◽  
The Difference ◽  
First Time

AbstractMany insects have triplets of camera type eyes, called ocelli, whose function remains unclear for most species. Here, we investigate the ocelli of the bumblebee, Bombus terrestris, using reconstructed 3D data from X-ray micro computed-tomography scans combined with computational ray-tracing simulations. This method enables us, not only to predict the visual fields of the ocelli, but to explore for the first time the effect that hair has on them as well as the difference between worker female and male ocelli.We find that bumblebee ocellar fields of view are directed forward and dorsally, incorporating the horizon as well as the sky. There is substantial binocular overlap between the median and lateral ocelli, but no overlap between the two lateral ocelli. Hairs in both workers and males occlude the ocellar field of view, mostly laterally in the worker median ocellus and dorsally in the lateral ocelli. There is little to no sexual dimorphism in the ocellar visual field, suggesting that in B. terrestris they confer no advantage to mating strategies.We compare our results with published observations for the visual fields of compound eyes in the same species as well as with the ocellar vision of other bee and insect species.

scholarly journals The Role of Fine Needle Aspiration of Orbital Lesions: A Case Series

2016 ◽  
Vol 60 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Fabio Pagni ◽  
Marta Jaconi ◽  
Andrew James Smith ◽  
Ambrogio Brenna ◽  
Maria Gabriella Valente ◽  
...  
Keyword(s):  
Case Series ◽  
Needle Aspiration ◽  
Lesion Size ◽  
Fine Needle ◽  
Computed Tomography Scans ◽  
The Mean ◽  
The Right ◽  
First Time ◽  
Orbital Lesions

Objective: This paper analyzes a series of ultrasound (US)-guided orbital fine needle aspirations (FNAs) which provide diagnostic information that cytopathologists approaching orbital lesions for the first time can find useful and underlines the importance of teamwork. Study Design: The investigators retrospectively obtained data from 24 consecutive orbital FNAs. For all patients, a complete clinicoradiological database was created. FNAs were performed under US guidance with 25-gauge needles and an aspiration biopsy syringe gun, and sent to the Department of Pathology for examination and data management. Results: The mean age of the patients was 54 years. Imaging studies included US, magnetic resonance imaging and computed tomography scans; 9 lesions involved the right orbit and 15 the left orbit. The mean lesion size was 23.6 ± 7.2 mm. After microscopic examination, 7 smears were labeled as ‘nondiagnostic', while in 17 cases a definitive diagnosis was proposed, which always proved to be correct (70.8%, specificity = 100%). Conclusions: The investigators believe that FNA biopsy of orbital masses is a necessary step; its weaknesses lie in the particularly delicate site of sampling and the extreme heterogeneity of lesions. Nevertheless, when orbital FNA is performed within a well-coordinated multidisciplinary team, it is a powerful tool that can be used to define the most appropriate management of these patients.

scholarly journals The Role of the Active Site Tyrosine in the Mechanism of Lytic Polysaccharide Monooxygenase

2020 ◽  
Author(s):  
Aina McEvoy ◽  
Joel Creutzberg ◽  
Raushan Kumar Singh ◽  
Morten J. Bjerrum ◽  
Erik Hedegård
Keyword(s):  
Active Site ◽  
Density Functional ◽  
Renewable Resource ◽  
Lytic Polysaccharide Monooxygenase ◽  
Functional Theory ◽  
Polysaccharide Monooxygenases ◽  
Active Site Tyrosine ◽  
The Difference ◽  
First Time

Natural polysaccharides (such as cellulose) comprise a large bio-renewable resource. However, exploitation of this resource requires energy-efficient polysaccharide degradation, which is currently limited by the inherent recalcitrance of many naturally occurring polysaccharides. Catalytic breakdown of polysaccharides can be achieved more efficiently by means of the enzymes lytic polysaccharide monooxygenases (LPMOs). However, the LPMO mechanism has remained controversial, preventing full exploitation of their potential. One of the controversies has centered around an active site tyrosine, present in most LPMOs. Different roles for this tyrosine have been proposed without direct evidence, but two recent investigations have for the first time obtained direct (spectroscopic) evidence for that chemical modification of this tyrosine is possible. Surprisingly, the spectroscopic features obtained in the two investigations are remarkably different. In this paper we use density functional theory (DFT) in a QM/MM formulation to reconcile these (apparently) conflicting results. By modeling the spectroscopy as well as the underlying reaction mechanism we can show how formation of two isomers (both involving deprotonation of tyrosine) explain the difference in the experimental observed spectroscopic features. The link between our structures and the observed spectroscopy provides a firm ground to investigate the role of tyrosine.

scholarly journals Features of a lullaby as a type of polycode text

2020 ◽  
pp. 158-168
Author(s):  
Ariuka I. Gelyaeva ◽  
Dzhamiliyat Dzh. Khuchinaeva
Keyword(s):  
Main Method ◽  
Linguistic Understanding ◽  
Nature Of Information ◽  
The Difference ◽  
First Time ◽  
Communicative Space ◽  
Empirical Material ◽  
Main Strategy

The article is devoted to identification of the features of the Karachai-Balkarian lullaby as a text of a complex semiotic nature and determination of the role of verbal and non-verbal components in the organization of an integral communicative space. It is postulated that the difference in sign is characteristic not only of modern texts, born of scientific and technological progress, which changed the sign nature of information, but also of a lullaby. It is noted that in linguistics, the study of a lullaby as a polycode text is not one of the intensively developed ones, and in the Karachai-Balkarian language its linguistic understanding and description as a multilayered text is carried out for the first time, which determines the relevance of the work. The main method for analyzing empirical material is the semiotic method of studying the text as an integral system of interdependent signs and symbols. Elements of discourse and phonosemantic analysis are also used. The article separately examines various semiotic layers and components syncretically presented in the text of the lullaby. The article analyzes the units of the lexical-semantic and grammatical levels of the language, which represent the verbal layer, as well as non-verbal means used in addition to the language code that accompany the verbal text of the song. Refrain “ballyau-ballyau”, “bellyay-bellyay” and the dominant sounds of the text «l-l’», «б-б’» according to their acoustic and physical characteristics, they are subordinated to the main strategy of a lullaby - calming and lulling a child. Particular attention is paid to determining the role of verbal and non-verbal signs in the implementation of synsemantics of the text of a lullaby. The novelty of the research lies in the identification of the specificity of the lullaby as a text of a different-sign nature, which manifests itself in the syncretism of various semiotic components, which in the text space are in complementarity relations. The multidimensionality of vectors of interaction of verbal, paraverbal, kinetic, symbolic components in a lullaby is revealed. It has been established that the verbal layer mainly performs an informative function, non-verbal means - expressive and pictorial functions.

scholarly journals Radiomorphometric Quantitative Analysis of Vasculature Utilizing Micro–Computed Tomography and Vessel Perfusion in the Murine Mandible

2012 ◽  
Vol 5 (4) ◽  
pp. 223-229 ◽  
Author(s):  
Xi Lin Jing ◽  
Aaron S. Farberg ◽  
Laura A. Monson ◽  
Alexis Donneys ◽  
Catherine N. Tchanque-Fossuo ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Quantitative Measure ◽  
Micro Ct ◽  
Vascular Networks ◽  
Sprague Dawley ◽  
Micro Computed Tomography ◽  
Craniofacial Skeleton ◽  
Sprague Dawley Rats ◽  
Quantitative Data Analysis

Purpose Biomechanical, densitometric, and histological analyses have been the mainstay for reproducible outcome measures for investigation of new bone formation and osseous healing. Here we report the addition of radiomorphometric vascular analysis as a quantitative measure of vascularity in the murine mandible. To our knowledge this is the first description of using micro–computed tomography (micro-CT) to evaluate the temporal and spatial pattern of angiogenesis in the craniofacial skeleton. Methods The vessel perfusion technique was performed on 10 Sprague-Dawley rats using Microfil (MV-122, Flow Tech; Carver, MA). After decalcification, hemimandibles were imaged using high-resolution micro-CT. Six separate radiomorphometric vascular metrics were calculated. Results Radiomorphometric values were analyzed using three different thresholds on micro-CT. Experimentally, 1000 Hounsfield units was found to be the optimal threshold for analysis to capture the maximal vascular content of the bone. Data from seven hemimandibles were analyzed. Minimal statistical variance in each of the quantitative measures of vascularity resulted in reproducible metrics for each of the radiomorphometric parameters. Conclusions We have demonstrated that micro-CT vascular imaging provides a robust methodology for evaluation of vascular networks in the craniofacial skeleton. This technique provides 3D quantitative data analysis that differs significantly from laser Doppler and microsphere methods, which simply measure flow. This technique is advantageous over labor-intensive 2D conventional analyses using histology and X-ray microangiography. Our data establish the appropriate thresholding for optimal vascular analyses and provide baseline measurements that can be used to analyze the role of angiogenesis in bone regeneration and repair in the craniofacial skeleton.

scholarly journals Using micro-CT techniques to explore the role of sex and hair in the functional morphology of bumblebee (Bombus terrestris) ocelli

2019 ◽  
Vol 158 ◽  
pp. 100-108 ◽  
Author(s):  
David Wilby ◽  
Tobio Aarts ◽  
Pierre Tichit ◽  
Andrew Bodey ◽  
Christoph Rau ◽  
...  
Keyword(s):  
Functional Morphology ◽  
Bombus Terrestris ◽  
Micro Ct

Discrete angle rotations of Bi nanoparticles embedded in a Ga matrix

Open Physics ◽  
2010 ◽  
Vol 8 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Avraham Be’er ◽  
Richard Kofman ◽  
Yossi Lereah
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Particle Size ◽  
Time Resolved ◽  
Transmission Electron ◽  
The Difference ◽  
First Time ◽  
Microscopy Images ◽  
Bi Nanoparticles

AbstractSpontaneous instabilities of nanoparticles are known to be influenced by the temperature, and strongly depend on the particle size. However, it is not clear what is the role of the surrounding material that is in contact with the particle. Here we report on the difference between spontaneous rotations of Bi nanoparticles embedded in amorphous SiO and those embedded in liquid Ga. The phenomenon was studied quantitatively by time resolved transmission electron microscopy using Fourier Transform analysis of highresolution electron microscopy images. While rotations of Bi nanoparticles embedded in amorphous SiO occur by all angles, the rotations of Bi nanoparticles embedded in liquid Ga occur by discrete angles. Our results point quantitatively, for the first time, to the role and importance of the contacting surrounding surface during the rotation of nanoparticles.

scholarly journals Effect of Different Dimensions of Test Samples on the Volumetric Change Assessment Of Endodontic Materials

2021 ◽  
Vol 32 (1) ◽  
pp. 42-47
Author(s):  
Fernanda Ferrari Esteves Torres ◽  
Juliane Maria Guerreiro-Tanomaru ◽  
Jader Camilo Pinto ◽  
Mario Tanomaru-Filho
Keyword(s):  
Morphological Changes ◽  
Micro Ct ◽  
Volume Loss ◽  
Micro Computed Tomography ◽  
Volumetric Change ◽  
Before And After ◽  
Different Dimensions ◽  
The Difference ◽  
The Stability ◽  
Different Diameters

Abstract New methodologies using micro-CT to evaluate solubility besides dimensional and morphological changes of endodontic materials are proposed. However, there is no standardization in the methods. The aim of this study was to assess the effect of different dimensions of test samples on volumetric change evaluation of different endodontic materials. AH Plus, FillCanal and Sealapex root canal sealers, Biodentine, IRM and MTA root-end filling cements were used in the tests. Samples of each material with a thickness of 1.5 mm and different diameters were manufactured: 6.3, 7.75, and 9.0 mm. The samples were scanned in micro-computed tomography (micro-CT) after setting and after 7 days of immersion in distilled water. The volumetric change was evaluated by means of the difference in the total volume of the specimens before and after immersion. Data were submitted to ANOVA and Tukey tests (p<0.05). The size of the samples did not affect the percentage of volumetric change of the materials (p>0.05). All sample sizes had greater volume loss for Sealapex among the sealers and Biodentine for the cements (p<0.05). In conclusion, Biodentine and Sealapex had the highest volume loss after immersion. Samples with 1.5 mm thickness, and diameters ranging between 6.3 and 9.0 mm can be used to assess the stability of endodontic materials using micro-CT without affecting the percentage of volumetric change.

scholarly journals The Study of Specific Surface Area from Carbonat Rock Using Micro Computed Tomography (µ-CT)

2017 ◽  
Vol 1 ◽  
pp. 111-113
Author(s):  
Mahendra Risky Habibi ◽  
Thaqibul Fikri Niyartama
Keyword(s):  
Computed Tomography ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Calculation Result ◽  
Carbonate Rocks ◽  
Programming Algorithm ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
The Difference

Carbonate rocks have been scanned and reconstructed in order to get the value of specific surface area. We get it from the reservoir at a depth of 1000 metres in South Sumatra. Skyscan Micro-CT 1173 is used for throwing and thresholding images using Global Otshu to characterize rocks. Our calculation result shows that the value of specific surface area of carbonate rocks show results 100 to 10-2 using the programming Algorithm Fuzzy C-Mean. The difference in values far enough that it can be assumed that the carbonate rocks have a heterogeneous surface area. In addition, histogram model shows the similarity of the sample. The macro sample has the same characteristics as the micro sample.

scholarly journals Comorbidity between depression and anxiety: assessing the role of bridge mental states in dynamic psychological networks

BMC Medicine ◽  
2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Robin N. Groen ◽  
Oisín Ryan ◽  
Johanna T. W. Wigman ◽  
Harriëtte Riese ◽  
Brenda W. J. H. Penninx ◽  
...  
Keyword(s):  
Mental State ◽  
Mental States ◽  
Symptom Clusters ◽  
Depression And Anxiety ◽  
Comorbid Depression ◽  
Vector Autoregressive ◽  
Credible Intervals ◽  
The Difference ◽  
First Time

Abstract Background Comorbidity between depressive and anxiety disorders is common. A hypothesis of the network perspective on psychopathology is that comorbidity arises due to the interplay of symptoms shared by both disorders, with overlapping symptoms acting as so-called bridges, funneling symptom activation between symptom clusters of each disorder. This study investigated this hypothesis by testing whether (i) two overlapping mental states “worrying” and “feeling irritated” functioned as bridges in dynamic mental state networks of individuals with both depression and anxiety as compared to individuals with either disorder alone, and (ii) overlapping or non-overlapping mental states functioned as stronger bridges. Methods Data come from the Netherlands Study of Depression and Anxiety (NESDA). A total of 143 participants met criteria for comorbid depression and anxiety (65%), 40 participants for depression-only (18.2%), and 37 for anxiety-only (16.8%) during any NESDA wave. Participants completed momentary assessments of symptoms (i.e., mental states) of depression and anxiety, five times a day, for 2 weeks (14,185 assessments). First, dynamics between mental states were modeled with a multilevel vector autoregressive model, using Bayesian estimation. Summed average lagged indirect effects through the hypothesized bridge mental states were compared between groups. Second, we evaluated the role of all mental states as potential bridge mental states. Results While the summed indirect effect for the bridge mental state “worrying” was larger in the comorbid group compared to the single disorder groups, differences between groups were not statistically significant. The difference between groups became more pronounced when only examining individuals with recent diagnoses (< 6 months). However, the credible intervals of the difference scores remained wide. In the second analysis, a non-overlapping item (“feeling down”) acted as the strongest bridge mental state in both the comorbid and anxiety-only groups. Conclusions This study empirically examined a prominent network-approach hypothesis for the first time using longitudinal data. No support was found for overlapping mental states “worrying” and “feeling irritable” functioning as bridge mental states in individuals vulnerable for comorbid depression and anxiety. Potentially, bridge mental state activity can only be observed during acute symptomatology. If so, these may present as interesting targets in treatment, but not prevention. This requires further investigation.

scholarly journals Cardiac Micro–Computed Tomography for Morphological and Functional Phenotyping of Muscle LIM Protein Null Mice

2007 ◽  
Vol 6 (4) ◽  
pp. 7290.2007.00022 ◽  
Author(s):  
Cristian T. Badea ◽  
Laurence W. Hedlund ◽  
Julie F. Boslego Mackel ◽  
Lan Mao ◽  
Howard A. Rockman ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
Blood Pool ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Isotropic Resolution ◽  
Lim Protein ◽  
Muscle Lim Protein ◽  
The Difference ◽  
Time Required

The purpose of this study was to investigate the use of micro–computed tomography (micro-CT) for morphological and functional phenotyping of muscle LIM protein (MLP) null mice and to compare micro-CT with M-mode echocardiography. MLP null mice and controls were imaged using both micro-CT and M-mode echocardiography. For micro-CT, we used a custom-built scanner. Following a single intravenous injection of a blood pool contrast agent (Fenestra VC, ART Advanced Research Technologies, Saint-Laurent, QC) and using a cardiorespiratory gating, we acquired eight phases of the cardiac cycle (every 15 ms) and reconstructed three-dimensional data sets with 94-micron isotropic resolution. Wall thickness and volumetric measurements of the left ventricle were performed, and cardiac function was estimated. Micro-CT and M-mode echocardiography showed both morphological and functional aspects that separate MLP null mice from controls. End-diastolic and -systolic volumes were increased significantly three- and fivefold, respectively, in the MLP null mice versus controls. Ejection fraction was reduced by an average of 32% in MLP null mice. The data analysis shows that two imaging modalities provided different results partly owing to the difference in anesthesia regimens. Other sources of errors for micro-CT are also analyzed. Micro-CT can provide the four-dimensional data (three-dimensional isotropic volumes over time) required for morphological and functional phenotyping in mice.

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