Truss Network Research Articles

Determination of population stock units of Portunus sanguinolentus (Herbst, 1783) as a non-target species (secondary species) using Truss Network Analysis on Madura Island

Abstract The blue swimming crab is one of the fishery commodities that constitute the major component of Indonesia’s third highest export products after shrimp and fish. The slightly expensive crabs in the market include Portunus pelagicus, which is commonly found in Indonesia alongside Portunus sanguinolentus. However, P. sanguinolentus is considered a secondary species due to the lower catch numbers in the country, specifically on Madura Island. The research about this particular crab is still very limited and the importance of information on secondary species stock units is to restore degraded ecosystems through appropriate programmes. Truss Network Analysis (TNA) was applied to measure the crab’s morphometric characteristics. The Kruskal–Wallis test, cluster analysis, and discriminant analysis were the statistical methods used to identify the stock units. The results showed different characteristics of swimming crabs in four locations on Madura Island, namely in the Bangkalan, Sampang, Pamekasan, and Sumenep Regencies. These indicated that different characteristics exist in male crabs found in Bangkalan, Sumenep, and Sampang, which have the highest level of similarity. In contrast, the females formed two clusters consisting of the groups Sampang and Sumenep, as well as Bangkalan and Pamekasan. The group differences show the potential of all crabs in the four locations to have more than one stock unit, hence their management needs to be differentiated.

Integrative Taxonomy Suggests Resurrection of Species of the Astyanax bimaculatus Group (Characiformes, Characidae).

Using integrative tools can be effective for species identification, especially in complex groups like Astyanax. Astyanax bimaculatus group is composed of six valid species, including A. lacustris. "A. altiparanae", "A. asuncionensis", and "A. jacuhiensis" are considered as junior synonyms of A. lacustris. Seeking to test the operational taxonomic unit (OTU) status of the junior synonyms of A. lacustris ("A. altiparanae", "A. asuncionensis", and "A. jacuhiensis"), we used analyses through mitochondrial DNA (COI and Cytb), cytogenetic markers (classical and molecular), and morphometry ("truss network"). Analysis of mitochondrial DNA sequences separated A. lacustris from the other synonymized species. The cytogenetic and morphometric analyses did not corroborate the synonymization and suggest that besides A. lacustris, the OTUs A. altiparanae, A. asuncionensis, and A. jacuhiensis are valid species. The analysis of different characters proposed by the integrative taxonomy used on the same individuals could provide greater reliability and minimize the underestimation of biodiversity.

A computational two-scale approach to cancellous bone remodelling

We propose a novel two-scale (meso-macro-scale) approach to computationally capture cancellous bone remodelling allowing for efficient and effective numerical implementation. Therein, the macro-scale is governed by the well-established kinematics and kinetics of one-scale continuum bone remodelling. However, the constitutive behaviour is not postulated phenomenologically at the macro-scale, but rather follows from the meso-scale. There, for the sake of computational efficiency, the trabecular architecture is idealised as a truss network with the cross-sectional area of the trabeculae adapting to mechanical loading. Then, the meso- and the macro-scale are coupled through up- and down-scaling. Computational results on benchmark problems from bio-mechanics demonstrate that the proposed two-scale approach is effective from a modelling perspective and efficient from a computational perspective. In particular, it automatically captures anisotropy resulting from the irregular trabecular architecture at the meso-scale, and, most importantly, enables the direct investigation of different trabecular structures at the meso-scale, thereby serving as a virtual “magnifiying glass”. As an outlook, the proposed two-scale approach to cancellous bone remodelling provides an excellent launch pad for further extension, e.g., by considering more complex trabecular architectures and/or through inclusion of micro-scale bone cellular activities.

Characterisation of phenotypic stock diversity of the crescent perch, Terapon jarbua (Forsskål, 1775) along the Indian coast using morphology and otolith shape analysis

Crescent Perch, Terapon jarbua is one of the important food cum marine ornamental fish in India. The present study deals with the delineation of T. jarbua stocks along the Indian coast using the morphology of fish and otolith shape analysis. A total of 609 fish samples were collected from six major fishing harbours representing the Indian coast from February to May 2022. The conventional morphometry, truss network analysis and otolith shape indices revealed the morphological divergence for the fish among the stocks. However, meristic traits could not show the variations among the different stocks. The morphometric and otolith shape variability for the species revealed the existence of different phenotypic stocks along the Indian coast, which might be due to the ability of the T. jarbua to adapt to different environmental conditions. The study highlights the need for separate biological and stock assessment studies for developing effective management strategies.

Population structure of commercially important groupers in the coral triangle Gorontalo, Indonesia to support conservation

Abstract. Achmad DS, Nurdin MS, Taslim I, Moore AM. 2023. Population structure of commercially important groupers in the coral triangle Gorontalo, Indonesia to support conservation. Biodiversitas 24: 6592-6601. Appropriate management units are fundamental to the conservation of species and ecosystems. In the case of exploited fishes, sustainable approaches to fisheries management are generally based on population units (stocks). This study aimed to address the lack of data to define the population structure of the stocks of two commercially important grouper species (Variola albimarginata (Baissac, 1953) and Variola louti (Forsskål, 1775)) in the Sulawesi Sea and Tomini Bay waters of Gorontalo Province, Sulawesi, Indonesia, in the Wallacea biodiversity hotspot. We used a combined morphometric and molecular (DNA barcoding, COI marker). We used truss network analysis with 14 characters to evaluate inter and intraspecies morphometric differences. DNA was extracted (Qiagen protocols) from tissue samples from individuals of both species in both sea areas, followed by polymerase chain reaction (PCR) and Sanger sequencing. Sequence processing and phylogenetic analyses conducted in MEGA X. Both approaches show clear separation between V. albimarginata and V. louti but indicate close kinship between the north coast (Sulawesi Sea) and south coast (Tomini Bay) populations of these groupers. Under the authority of the Gorontalo Province Marine and Fisheries Service, these two populations could be managed as one stock without compromising fisheries sustainability or the conservation of these ecologically and economically valuable species.

Morphometrical characters of Atlantic horse mackerel Trachurus trachurus (Linnaeus, 1758), in the North Atlantic zone of Morocco

The Atlantic Horse mackerel Trachurus trachurus (Linnaeus, 1758) is subject to considerable fishing pressure. under strong fishing pressure, the objective of the research is to establish the species morphological characterization: the growth model, sex-ratio and the body condition factor, using standard morphometric methods and truss network analysis. 1494 samples were collected from the North Moroccan Atlantic coast, sampling was carried out from July 2021 to July 2022 at the port of Tangier and Larache (35°47, 33°89), indeed individuals total length measured between10 and 41 cm and the body weight presented between 35 and 500 g, All morphometrical analyses showed similar results, The values for males, females and the total sample showed that the growth of T. trachurus was minor, which that mean the weight grows less quick than the length, The condition factor was calculated indicating the smallest values were observed in the range of Total length between 10 and 19 cm.

Chelidonichthys lucerna (Linnaeus, 1758) Population Structure in the Northeast Atlantic Inferred from Landmark-Based Body Morphometry.

The study of geometric morphometrics among stocks has proven to be a valuable tool in delineating fish spatial distributions and discriminating distinct population units. Variations in fish body morphology can be linked to genetic factors or to phenotypic adaptability in response to environmental variables. The tub gurnard (Chelidonichthys lucerna) is a demersal species that usually lives in the bottom of the continental shelf, being widely distributed along the northeast Atlantic, Mediterranean and Black seas. Worldwide interest in the species has increased since 2006, when ICES recognized its potential for commercial exploitation. However, despite its broad geographic occurrence, to date, research on C. lucerna population structure at large spatial scales is still lacking. In this paper, body geometric morphometrics, using a landmark-based truss network, was applied in order to discriminate C. lucerna populations caught in three different fishery grounds areas along the northeast Atlantic: Conwy Bay (United Kingdom), Biscay Bay (Spain) and Matosinhos (Portugal). The results obtained in this study revealed a high overall relocation success (95%) of samples to their original locations, thus demonstrating the existence of significant regional differences and indicating that we are dealing with different fish population units. Moreover, the data revealed a partial overlap between individuals from Spain and United Kingdom, suggesting that in geographically distant areas these populations may inhabit similar environments. However, to corroborate these findings, future works using a holistic approach with alternative and complimentary stock assessment tools (e.g., genetic and phenotypic natural tags) are highly recommended.

Morphometric Study of Swimming Crab (Portunus pelagicus) Using Truss Network Analysis for Determination of Stock Structure in FMA 711

The crab of Portunus pelagicus is a fishery resource with a wide distribution area and quite diverse environmental conditions in Indonesia, giving rise to morphometric diversity. The study aims to analyze differences in morphometric diversity of crab populations (P. pelagicus) in the waters of Indonesian Fisheries Management Area (FMA) 711, landed in Bintan, Bangka, and Ketapang, which can describe the condition of the crab stock units. A total of 300 individuals were collected from all locations using random sampling. The crab morphometric characters were analyzed using Truss Network body shape method (TNA). The Kruskal Wallis results analysis showed distinguishing in some morphometric characters for both carapace and abdomen. Cluster analysis shows that there were two population groups: The Bintan group, and the Bangka-Ketapang groups. The discriminant analysis on the carapace characters resulting that the crabs from three locations have the potential for more than one stock unit, so different management is needed.

A nodal-based optimization method for the design of continuous fiber-reinforced structures

The mechanical performance of fiber-reinforced structures highly relies on fibers' paths in the matrix material. Unlike the level set method that offsets the zero-level contours of a higher-dimensional function, this work shifts the nodes of a truss network within an optimization framework to design individual paths specifically. All intersection manners of a single fiber with the rectangular continuum element are considered in the finite analysis to retrieve mechanical responses within an acceptable error margin numerically. The design variables, namely node coordinates, are updated via the method of moving asymptotes under the guide of the sensitivity of the objective function, which is smoothed using a radial basis function. After each optimization iteration, the paths are slightly adjusted to avoid twisting problems and control fiber gaps using a polynomial interpolation scheme. Numerical examples illustrate that the proposed method can generate elegant fiber paths within a few steps. In the meantime, the optimization efficiency is improved as the design variables are significantly reduced. Compared with existing methods, we found that lower objective values can be achieved as allowing nodes to move freely in the design domain guarantees a global minimum theoretically.

Expansive spalling mechanism of concrete due to high temperature based on developed hygro-thermal-mechanical model by 3D-RBSM-TNM

Explosive spalling of concrete has been explained based on thermal stress and vapor pressure, and the mechanism of explosive spalling has been still discussed. In this study, the influence of several factors on the mechanism of explosive spalling due to high temperature was validated using the coupled analytical system: Rigid Body Spring Model-Truss Network Model (RBSM-TNM) based on hygro-thermal mechanical model. Truss Network Model can evaluate the heat transfer and vapor pressure transfer. The thermal stress and vapor pressure are applied to 3D-RBSM as an initial strain and initial stress, respectively. This proposed analysis can describe the complicated explosive spalling phenomena. Moreover, the accumulation of vapor pressure in the cracks and the change in mechanical property due to high temperature can be taken into account. In this paper, the influences of thermal stress, vapor pressure, vapor pressure transfer through cracks, and the change in mechanical property due to high temperature on the explosive spalling are precisely elucidated. As a result, it was confirmed that thermal stress causes the distributed cracks at the internal area while it does not involve the explosive spalling and a trigger of explosive spalling is the vapor pressure.

Comparative Morphometric Analysis of the Azov Anchovy (<i>Engraulis encrasicolus maeoticus</i> Pusanov, 1926) and the Black Sea Anchovy (<i>E. encrasicolus ponticus</i> Alexandrov, 1927) Based on the Body Shape

A comparative analysis of body shape was performed on 841 specimens of anchovy collected from 21 catches from the Sea of Azov, the Kerch Strait, and the Black Sea off the Crimea and the northeastern coast of the Caucasus in 2006–2007 and 2016–2017. Twenty-three measurements between 12 homologous landmarks of the body of each specimen according to the “Truss Network System” served as characters for analysis. Fifteen characters showed significant differences between the Azov anchovy Engraulis encrasicolus maeoticus Pusa-nov, 1926 and the Black Sea anchovy E. encrasicolus ponticus Alexandrov, 1927. Specimens of the Azov subspecies had larger relative values for all characters of the head region, the height of the trunk region, the re-lative length of the bases of the dorsal and anal fins, and the height of the base of the caudal fin. Specimens of the Black Sea subspecies had a greater postdorsal length and a larger distance from the end of the dorsal fin base to the end of the anal fin base. A multivariate principal component analysis revealed the highest variabi-lity of characters of body height, which depends on the fatness of the fish and demonstrates seasonal dyna-mics. The second group combines characters that do not have a seasonal component (dimensions of the head region, lengths of the bases of the dorsal and anal fins, and postdorsal distance) and can be used for distinguishing the shape of the Azov and Black Sea anchovies. The success rate of classification of Azov and Black Sea anchovies according to the body shape measurement characters using the discriminant analysis was 83.4%.

Automatic construction of tensegrity structures with complex surfaces based on circle packing

Tensegrities have attracted significant attention in many disciplines as a distinct type of truss network. However, with the increase in size and complexity, building complex tensegrities remains challenging. This study presents a systematic method to automatically construct large-scale tensegrity structures with complex surfaces by ingeniously combining circle packing. This method enables direct identification of the topology and configuration of tensegrities with specific shapes. First, circle packings on target surfaces are accomplished in a practical manner. On this basis, the triangulation connection is established as the basic assembly pattern, and its mobility is further analyzed using the screw theory to inspect the assembly rules. Then, the connection requirements of the elementary units are investigated, and a novel tensegrity torus is exemplarily utilized for assembly. To evaluate the tensegrity properties, the self-equilibrium and stability of the assembled structures are respectively examined. For illustration, four representative examples are produced to verify the effectiveness of the proposed method. In this study, an alternative method to automatically manufacture tensegrities satisfying the demands of both aesthetics and practicality is developed, which will significantly expand the application scenarios for tensegrity systems.

Study of morphological variation between wild and farm-bred Mascara barbs (Jerdon, 1849) based on truss network analysis

Study of morphological variation between wild and farm-bred Mascara barbs (Jerdon, 1849) based on truss network analysis

Stock structure based on truss network analysis, length-weight relationship and condition factor of Decapterus macrosoma (Bleeker, 1851) from two fishing areas, Red Sea, Egypt

Stock structure based on truss network analysis, length-weight relationship and condition factor of Decapterus macrosoma (Bleeker, 1851) from two fishing areas, Red Sea, Egypt

Data driven approach in multiphysics framework: Application to coupled electro-mechanical problems

Solving coupled multiphysics problems using finite elements and conventional modeling approach requires building, from coupled finite element formulation often in the same code, the monophysical operators and the multiphysics coupling operators. In this work the data driven, model-free computational approach is fitted in the multiphysics framework adapted for ‘smart’ materials. Thus, in this work we ought to expand the phase space and propose a new norm for the distance based data driven solver adapted to the problem at hands. Given the good material database which naturally encodes the coupling interactions, we show that proposed application of data driven approach enables to avoid the coupling tangent terms altogether. In other words, the data driven approach permits to decouple the different ‘physics’ and to manage the coupling from the data. We illustrate the performance and robustness of the approach on two examples related to lattice model composed of planar, piezoelectric truss network and of finite element discretized linear piezoelectric solids. The numerical tests show good convergence properties related to the number of data points, as well as the choice of material and weighting parameters.

Phenotypic variation of Chitala chitala (Hamilton, 1822) from Indian rivers using truss network and geometric morphometrics.

Chitala chitala (Hamilton, 1822) is an economically important food fish species occurring throughout Indian rivers, which also has ornamental value. This study focuses on morphological variations in C. chitala from seven river basins across India namely; Son, Tons, Ken, Brahmaputra, Ganga, Gomti and Gandak. A truss network was constructed by interconnecting nine landmarks to generate 36 morphometric variables extracted from digital images of specimens sampled from the study locations. Transformed truss measurements were subjected to principal component analysis (PCA), canonical discriminant function analysis (CDFA) and discriminant analyses of principal components (DAPC). DAPC function coefficients performed much better in capturing the variation pattern and discrimination between the rivers which was not achieved using CDFA. Eight truss variables were identified with significant and highest loading for truss variables on principal components and coefficients on discriminant function from DAPC contributing to maximum variation between the rivers. Performance graph and functional distribution of identified truss variables clearly indicated distinction between the rivers. Thin plate spline analysis and procrustes shape analysis further showed the variation in morphology between specimens across the rivers. The significant parameters differentiating specimens from different rivers were linked to dorsal fin origin, the base of the pectoral fin and the perpendicular point on the anal fin from the dorsal fin origin. Variation in the hydrodynamics of the rivers studied might be possibly affecting the fin kinematics and consequently leading to adaption seen as phenotypic variation in C. chitala. The results showcased in the present study shall help in better understanding of intra-specific diversity which is significant for management and conservation of a species.

Morphological Variation between Hatchery Bred and Wild Caught Anabas testudineus in Malaysia.

This study was designed to characterise the cultured and wild populations of Anabas testudineus in Malaysia using morphological parameters. Fish samples from the East and West coast of the country were obtained from fishermen (wild samples) and well-recognised climbing perch farmers in Kedah, Kelantan, Johor and Selangor. The Truss network method was applied to obtain necessary data and analysed to examine phenotypic variation between the cultured and wild stocks. Results obtained suggest that each hatchery population belonged to a distinct stock as revealed by their separate clustering into individual unique groups. However, an extensive overlap was observed in the wild population suggesting similarity of origin. The most important morphological parameters for the discrimination of the two populations are the homologous landmark B (i.e., snout to insertion of the pelvic fin) and C (i.e., above the eye to insertion of the pelvic fin). Genetic characterisation of the A. testudineus is needed to complement the findings of this study and establish a baseline for the development of a selective breeding programme for the fish species in Malaysia.

Stock Structure Analysis of the Endangered Queen Loach, Botia dario (Hamilton 1822) from Five Rivers of Northern Bangladesh by Using Morphometrics: Implications for Conservation

Identifying stock is key to sustainable fisheries management and conservation. Using traditional morphometrics (TMR) and image-based truss network analysis (ITNA), we evaluated the stock structure of the endangered queen loach, Botia dario. The study was carried out in the following five stocks in Bangladesh’s northern rivers: the Atrai, Dhorala, Danu, Jamuna, and Padma. The inventory regarding stock structure was investigated using a total of nine traditional morphometrics, 11 ratios, and 23 truss measurements for each individual. To generate 23 ITNA, 12 landmarks were used. To assess variations among the stocks, a principal component analysis (PCA), factor analysis (FA), canonical variate analysis (CVA), and cluster analysis (CA) were performed. Six principal components explained 91.50% of the variation in TMR, while seven principal components explained 73.425% of the variation in ITNA. CVA, using traditional methods and ratios were correctly classified as 65.0%, 42.0%, 64.2%, 89.3%, and 77.5% for Danu, Padma, Jamuna, Dhorala, and Atrai River stocks, respectively, based on original grouped classes. CVA using ITNA was correctly classified as 90.0%, 80.0%, 77.4%, 94.6%, and 98.6% for Danu, Padma, Jamuna, Dhorala, and Atrai River stocks, respectively, based on original grouped classes. CVA analysis based on TMR and ITNA showed that cannonical variates (CV1 to CV3) are related to the whole-body shape. Both TMR and ITNA formed two clusters. In the first cluster, the Jamuna and Atrai River stocks combinedly formed a separate stock based on (TMR). In ITNA, the Dhorala and Atrai River formed as separate stocks from the other four stocks. According to this study, combining TMR and ITNA analysis aids in the differentiation of various B. dario stocks. The stock separation of this species was supposed to be geographic disconnection, waterway nature, and temperature variations. The B. dario stocks are heavily exploited and the species is an ideal nominee for species variation to boost the aquaculture yield. Within-stock distinctions were revealed in this study, necessitating the identification of gene pools and molecular studies to achieve a deeper understanding of the stocks. Through a more scientific approach, this stock structure study may aid in the development of conservation programs for this endangered species.

Phenotypic plasticity in Barilius vagra (Hamilton, 1822) (Teleostei: Danionidae) from two geographically distinct river basins of Indian Himalaya

Truss-based morphometric analysis was used to examine phenotypic plasticity of Barilius vagra (Hamilton, 1822) inhabiting the tributaries of the Alaknanda (Ganga River basin) and Chenab (Indus River basin), two geographically distinct river basins in the Indian Himalaya. Fourteen landmarks were connected to generate a truss network of 90 parameters on the body of fish. Eighty morphometric traits out of ninety morphometric measurements explained statistically significant difference among six sampling locations of Barilius vagra from streams in the Alaknanda and Chenab basins. Discriminant function analysis revealed 82% of Barilius vagra specimens originally classified into their own groups. 95% of the variance was explained by 13 principal components. Morphometric characters (1–6, 1–13, 2–5, 2–6, 2–14, 3–6, 4–6, 4–14, 6–12, 7–8, 7–9, 10–11, and 13–14) contributed greatly in differentiation of B. vagra populations from different river basins. The Alaknanda basin reflected some mixing within populations, which may be due to common environmental conditions and fish migration in these streams. This study will be helpful in framing site-specific conservation and management strategies, such as net mesh size selection, avoiding overexploitation, stock augmentation and food availability for different fish populations.

Assessment of temperature effects on body shape in Nile tilapia, Oreochromis niloticus juveniles using the truss network system

Among the environmental factors, water temperature has a significant effect on many aspects of fish life. This study was carried out to examine effects of water temperature on body shape of Nile tilapia, Oreochromis niloticus during the early stages of life using truss network system. A total of 150 newly-born fry were reared in three temperature treatments (22, 28 and 34°C) for 40 days. At the end of experiment, the left side of the specimens was photographed. To achieve the body shape data, 13 landmark-points were digitized using tpsDig2 software. The extracted data were justified with generalized procrustes analysis, then the differences of body shape among groups were investigated using the principal component analysis (PCA), canonical variate analysis (CVA) and cluster analysis (CA). There were significant differences in body shape of the treatments. The results of CVA and CA indicated that one of the important factors in the aquatic habitats is water temperature that influences the body shape of the Nile tilapia during the first stages (larval and juvenile stages) of growth.