scholarly journals Thwarting predators? A three-dimensional perspective of morphological alterations in the freshwater crustacean Daphnia

PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0254263
Author(s):  
Martin Horstmann ◽  
Ralph Tollrian ◽  
Linda C. Weiss
Keyword(s):  
Morphological Changes ◽  
Three Dimensional ◽  
Foraging Strategies ◽  
Inducible Defenses ◽  
Predator Prey ◽  
Morphological Alterations ◽  
Morphological Adaptations ◽  
Freshwater Crustacean ◽  
Tadpole Shrimp ◽  
Interspecific Comparisons

Predation is a major selective agent, so that many taxa evolved phenotypically plastic defensive mechanisms. Among them are many species of the microcrustacean genus Daphnia, which respond to an increased predation risk by developing inducible morphological alterations. Some of these features are obvious and easily recognized, e.g., crests in D. longicephala, while others are rather hidden, such as the bulkier shape of D. magna induced by the presence of the tadpole shrimp Triops. In this study we investigated the extraordinary diversity of morphological adaptations in the presence of predators with different foraging strategies in six predator-prey systems. For the first time we were able to analyze the unexposed and predator-exposed morphs comprehensively using three-dimensional scanning and reconstruction. We show that morphological changes are manifold in appearance between species and predators, and go beyond what has been known from previous 2D analyses. This further demonstrates the enormous trait flexibility of Daphnia. Interestingly, we found that among this variety some species share morphological strategies to counter a predator, while others use a different strategy against the same predator. Based on these intra- and interspecific comparisons, we discuss the mechanisms by which the respective defense might operate. These data therefore contribute to a deeper understanding of the inducible defenses’ morphology as well as their diversified modes of operation in Daphnia, being a cornerstone for subsequent investigations, including the determination of costs associated with morphological change.

Three-dimensional mandibular changes associated with Class II elastics and extractions treatment in adult patients

2021 ◽  
Author(s):  
Hong Liu ◽  
Xun Xi ◽  
Dongxu Liu
Keyword(s):  
Orthodontic Treatment ◽  
Morphological Changes ◽  
Three Dimensional ◽  
Class Ii ◽  
Initial Position ◽  
Virtual Reference ◽  
Morphological Alterations ◽  
3 Dimensional ◽  
Slight Rotation ◽  
Class Ii Elastics

Abstract Backgroud: The apllication of Class II elastic can induce the rotation of mandible and condylar response. The purpose of this study was to assess the positional and morphological alterations of mandible after orthodontic treatment with Class II elastic by using of 3-dimensional superimposition of pretreatment (T1), posttreatment (T2) and after retention (T3) CBCT data. Methods: With sequential 3D superimpositions that combined cranial base superimpositions with regional mandibular superimpositions, the virtual reference mandibles were placed to distinguish morphological changes from positional changes. The morphological changes and positional changes of mandibles were measured by comparing multiple combinations of reference and original mandibles respectively, and the corresponding paired t test was performed using SPSS (IBM SPSS version 23). Results: During orthodontic treatment (T1-T2), the mandibular molars were extruded, and the condyles were revealed apparent adaptive remodeling and upward/backward displacements. The mandible rotated backwardly and drifted backwardly/downwardly. The condylar growth and displacements were significantly different. The condylar growth did not induce isometric displacements and the forward rotation was restricted. Two years after retention (T2-T3), continuous morphological and positional changes occurred. The condylar remodeling and forward/downward displacements induced forward mandibular rotation and neutralized the backward rotation during treatment period (T1-T2). The overall positional changes (T1-T3) were translations with slight rotation. Statistically significant differences were found between the treatment and overall variables regarding the 3D rotation, condylar displacement, Pog displacement. And with the continuous morphological and positional changes, the condyle moved back to the initial position after the retention stage.Conclusion: Conclusions: the sequential 3D superimposition method can produce the reference mandibles and distinguish the morphological changes from positional alterations. The class II elastics induced mandibular complex changes including condylar adaptive remodeling and 3D rotation and translation. The condyles morphologically adapted to resist the rotation effects of Class II elastic.

Thermal characterization of ABS-Graphene blended three dimensional printed functional prototypes for electro chemical energy storage

2018 ◽  
Vol 1 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Kamaljit Singh Boparai ◽  
Rupinder Singh
Keyword(s):  
Energy Storage ◽  
Structural Changes ◽  
Fused Deposition Modeling ◽  
Morphological Changes ◽  
Three Dimensional ◽  
Thermal Characterization ◽  
Chemical Energy ◽  
Flow Index ◽  
Fused Deposition

This study highlights the thermal characterization of ABS-Graphene blended three dimensional (3D) printed functional prototypes by fused deposition modeling (FDM) process. These functional prototypes have some applications as electro-chemical energy storage devices (EESD). Initially, the suitability of ABS-Graphene composite material for FDM applications has been examined by melt flow index (MFI) test. After establishing MFI, the feedstock filament for FDM has been prepared by an extrusion process. The fabricated filament has been used for printing 3D functional prototypes for printing of in-house EESD. The differential scanning calorimeter (DSC) analysis was conducted to understand the effect on glass transition temperature with the inclusion of Graphene (Gr) particles. It has been observed that the reinforced Gr particles act as a thermal reservoir (sink) and enhances its thermal/electrical conductivity. Also, FT-IR spectra realized the structural changes with the inclusion of Gr in ABS matrix. The results are supported by scanning electron microscopy (SEM) based micrographs for understanding the morphological changes.

Liver Toxicity in Rats Fed A Mixture of Pcb Congeners and 2,3,7,8-Tcdd

1997 ◽  
Vol 3 (S2) ◽  
pp. 51-52
Author(s):  
B.J. Cornell ◽  
A. Singh ◽  
I. Chu
Keyword(s):  
Aromatic Compounds ◽  
Liver Toxicity ◽  
Corn Oil ◽  
Morphological Changes ◽  
Test Substance ◽  
Sprague Dawley ◽  
Morphological Alterations ◽  
Pcb Congeners ◽  
Transmission Electron ◽  
Sprague Dawley Rats

Polyhalogenated aromatic compounds such as polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins (PCDDs) continue to be environmental contaminants because of their bioaccumulation in the food chain and high resistance to biodegradation. The current study was undertaken to determine if a mixture of PCB congeners (WHO-IPCS) were interactive with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in producing morphological changes in the rat liver. Both compounds are known to produce a broad range of biochemical and morphological alterations including enzyme induction.Groups (N=5) of female Sprague-Dawley rats were administered TCDD (0, 2.5, 25, 250, 1000 ng/kg bw/day) or PCB (0, 2, 20 μg/kg bw/day) alone, or in combination with each concentration of both compounds. Incorrect concentrations were published in a previous abstract. The test substance was mixed with corn oil and given by gavage at 2 ml/kg daily for 28 days. At the end of the experiment, the rats were killed and liver samples were prepared for transmission electron microscopy.

scholarly journals Autotetraploid Emergence via Somatic Embryogenesis in Vitis vinifera Induces Marked Morphological Changes in Shoots, Mature Leaves, and Stomata

Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1336
Author(s):  
Caterina Catalano ◽  
Loredana Abbate ◽  
Antonio Motisi ◽  
Dalila Crucitti ◽  
Vincenzo Cangelosi ◽  
...  
Keyword(s):  
Somatic Embryogenesis ◽  
Morphological Changes ◽  
Ploidy Levels ◽  
Dna Profile ◽  
Morphological Alterations ◽  
Cell Pair ◽  
Mature Leaves ◽  
Induction Process ◽  
Ploidy Changes ◽  
Dna Profiles

Polyploidy plays an important role in plant adaptation to biotic and abiotic stresses. Alterations of the ploidy in grapevine plants regenerated via somatic embryogenesis (SE) may provide a source of genetic variability useful for the improvement of agronomic characteristics of crops. In the grapevine, the SE induction process may cause ploidy changes without alterations in DNA profile. In the present research, tetraploid plants were observed for 9.3% of ‘Frappato’ grapevine somatic embryos regenerated in medium supplemented with the growth regulators β-naphthoxyacetic acid (10 µM) and N6-benzylaminopurine (4.4 µM). Autotetraploid plants regenerated via SE without detectable changes in the DNA profiles were transferred in field conditions to analyze the effect of polyploidization. Different ploidy levels induced several anatomical and morphological changes of the shoots and mature leaves. Alterations have been also observed in stomata. The length and width of stomata of tetraploid leaves were 39.9 and 18.6% higher than diploids, respectively. The chloroplast number per guard cell pair was higher (5.2%) in tetraploid leaves. On the contrary, the stomatal index was markedly decreased (12%) in tetraploid leaves. The observed morphological alterations might be useful traits for breeding of grapevine varieties in a changing environment.

scholarly journals Action of vanillin (Vanilla planifolia) on the morphology of tibialis anterior and soleus muscles after nerve injury

2017 ◽  
Vol 15 (2) ◽  
pp. 186-191 ◽  
Author(s):  
Ana Luiza Peretti ◽  
Juliana Sobral Antunes ◽  
Keli Lovison ◽  
Regina Inês Kunz ◽  
Lidyane Regina Gomes Castor ◽  
...  
Keyword(s):  
Nerve Injury ◽  
Tibialis Anterior ◽  
Morphological Analysis ◽  
Morphological Changes ◽  
Control Group ◽  
Vanilla Planifolia ◽  
Morphological Alterations ◽  
Injury Group ◽  
Fiber Atrophy ◽  
Oral Doses

ABSTRACT Objective To evaluate the action of vanillin (Vanilla planifolia) on the morphology of tibialis anterior and soleus muscles after peripheral nerve injury. Methods Wistar rats were divided into four groups, with seven animals each: Control Group, Vanillin Group, Injury Group, and Injury + Vanillin Group. The Injury Group and the Injury + Vanillin Group animals were submitted to nerve injury by compression of the sciatic nerve; the Vanillin Group and Injury + Vanillin Group, were treated daily with oral doses of vanillin (150mg/kg) from the 3rd to the 21st day after induction of nerve injury. At the end of the experiment, the tibialis anterior and soleus muscles were dissected and processed for light microscopy and submitted to morphological analysis. Results The nerve compression promoted morphological changes, typical of denervation, and the treatment with vanillin was responsible for different responses in the studied muscles. For the tibialis anterior, there was an increase in the number of satellite cells, central nuclei and fiber atrophy, as well as fascicular disorganization. In the soleus, only increased vascularization was observed, with no exacerbation of the morphological alterations in the fibers. Conclusion The treatment with vanillin promoted increase in intramuscular vascularization for the muscles studied, with pro-inflammatory potential for tibialis anterior, but not for soleus muscle.

Three-dimensional predator–prey interactions: a computer simulation of bird flocks and aircraft

1986 ◽  
Vol 64 (11) ◽  
pp. 2624-2633 ◽  
Author(s):  
Peter F. Major ◽  
Lawrence M. Dill ◽  
David M. Eaves
Keyword(s):  
Computer Simulation ◽  
Prey Species ◽  
Three Dimensional ◽  
Aircraft Engine ◽  
Aquatic Environments ◽  
Aircraft Engines ◽  
Predator Prey ◽  
Simulation Techniques ◽  
Computer Simulation Techniques ◽  
Individual Prey

Three-dimensional interactions between grouped aerial predators (frontal discs of aircraft engines), either linearly arrayed or clustered, and flocks of small birds were studied using interactive computer simulation techniques. Each predator modelled was orders of magnitude larger than an individual prey, but the prey flock was larger than each predator. Expected numbers of individual prey captured from flocks were determined for various predator speeds and trajectories, flock–predator initial distances and angles, and flock sizes, shapes, densities, trajectories, and speeds. Generally, larger predators and clustered predators caught more prey. The simulation techniques employed in this study may also prove useful in studies of predator–prey interactions between schools or swarms of small aquatic prey species and their much larger vertebrate predators, such as mysticete cetaceans.The study also provides a method to study problems associated with turbine aircraft engine damage caused by the ingestion of small flocking birds, as well as net sampling of organisms in open aquatic environments.

scholarly journals Right Ventricular Global and Regional Remodeling in American-Style Football Athletes: A Longitudinal 3D Echocardiographic Study

2021 ◽  
Vol 11 (8) ◽  
pp. 3357
Author(s):  
Amir Hodzic ◽  
Gabriel Bernardino ◽  
Damien Legallois ◽  
Patrick Gendron ◽  
Hélène Langet ◽  
...  
Keyword(s):  
Right Ventricular ◽  
Morphological Changes ◽  
Three Dimensional ◽  
Computational Method ◽  
Physiological Adaptation ◽  
Volumetric Assessment ◽  
American Style ◽  
Few Data ◽  
The Right ◽  
Field Position

Few data exist concerning the right ventricular (RV) physiological adaptation in American-style football (ASF) athletes. We aimed to analyze the RV global and regional responses among ASF-trained athletes. Fifty-nine (20 linemen and 39 non-linemen) ASF athletes were studied before and after inter-seasonal training. During this period, which lasted 7 months, all athletes were exposed to combined dynamic and static exercises. Cardiac longitudinal changes were examined using three-dimensional transthoracic echocardiography. A computational method based on geodesic distances was applied to volumetrically parcellate the RV into apical, outlet, and inlet regions. RV global and regional end-diastolic volumes increased significantly and similarly in linemen and non-linemen after training, with predominant changes in the apex and outlet regions. RV global and regional ejection fractions were preserved. Morphological changes were uniformly distributed among the four cardiac chambers, and it was independent of the field position. Assessment of RV end-diastolic global, inlet and apical volumes showed low intra-observer (3.3%, 4.1%, and 5.3%, respectively) and inter-observer (7%, 12.2%, and 9%, respectively) variability, whereas the outlet regional volumetric assessment was less reproducible. To conclude, ASF inter-seasonal training was associated with a proportionate biventricular enlargement, regardless of the field position. Regional RV analysis allowed us to quantify the amount of exercise-induced remodeling that was larger in the apical and outlet regions.

scholarly journals Morphological Alterations of CAD Cells Overexpressing AKT1

2020 ◽  
Vol 26 (S2) ◽  
pp. 1354-1358
Author(s):  
James Wachira
Keyword(s):  
Signal Transduction ◽  
Plasma Membrane ◽  
Cell Survival ◽  
Fluorescent Protein ◽  
Morphological Changes ◽  
Protein Localization ◽  
Signal Transduction Pathways ◽  
Morphological Alterations ◽  
Cellular Models ◽  
Cad Cells

AbstractCAD cells are neuronal cells used in studies of cell differentiation and in cellular models of neuropathology. When cultured in differentiation medium, CAD cells exhibit characteristics of mature neurons including the generation of action potential. In addition to being a central signaling kinase in cell survival, AKT1 plays important roles in the nervous system including neuroplasticity and this study examined the localization of exogenous AKT1 in CAD cells. Neuropeptides modulate many signal transduction pathways and melacortins are implicated in regulating growth factor signal transduction pathways, including the PI3K/AKT pathway. AKT1-DsReD was transfected into CAD cells that were stably expressing melanocortin 3-receptor-GFP (MC3R-GFP), a G-protein coupled receptor. The cells were imaged with confocal microscopy to determine the fluorescent protein localization patterns. AKT1-DsRed was predominantly localized in the cytoplasm and the nucleus. Further, expression of exogenous AKT1 in these cell lines led to morphological changes reminiscent of apoptosis. As expected, MC3R-GFP localized to the plasma membrane but it internalized upon cell stimulation with the cognate ligand. In limited areas of the plasma membrane, AKT1-DsRed and MC3R-GFP were colocalized. In conclusion, quantitative studies to understand the role of relative levels of AKT1 in determining cell survival are needed.

scholarly journals Morphological alterations in the heart and aorta of rats treated with glucocorticoids

2015 ◽  
Vol 32 (04) ◽  
pp. 231-235
Author(s):  
R. Dantas ◽  
K. Souza ◽  
D. Santos ◽  
V. Feitosa ◽  
E. Fioretto ◽  
...  
Keyword(s):  
Wistar Rats ◽  
Histological Analysis ◽  
Saline Solution ◽  
Morphological Changes ◽  
Morphological Structure ◽  
Control Group ◽  
Morphological Alterations ◽  
Heart Chamber ◽  
Male Wistar Rats ◽  
Synthetic Glucocorticoid

Abstract Introduction: The objective of this study was to analyze the morphological structure of the heart and aorta of rats treated with the synthetic glucocorticoid dexamethasone. Material and Methods: Male Wistar rats were divided into two groups: 08 control rats undergoing treatment with a 0.9% saline solution for 10 days and 08 rats treated for 10 days with dexamethasone (2mg/kg animal weight). Results: Histological analysis detected a mild cardiac hypertrophy and 15% reduction of collagen located in the aorta of animals treated with glucocorticoid when compared to the control group. Conclusion: We conclude that treatment with dexamethasone for a period of 10 consecutive days is able to promote morphological changes in the structure of the heart chamber and, impair morphological structure of aorta.

Sign in / Sign up

Export Citation Format

Share Document