scholarly journals A Comparison of Size, Shape, and Fractal Diversity Between Coral Rubble Sampled From Natural and Artificial Coastlines Around Okinawa Island, Japan

2021 ◽  
Vol 8 ◽  
Author(s):  
Giovanni D. Masucci ◽  
Piera Biondi ◽  
James D. Reimer

Substrate surface area and fractal complexity have been reported to influence the abundance and diversity of mobile cryptic animal communities. Surfaces with higher fractal dimensions not only offer additional space for colonization, but bias space availability toward smaller size ranges, increasing the number of available niches. Conversely, smaller surface areas tend to be associated with a decrease in abundances while reduced fractal complexities may support less diversity in the benthic community. In this study, we compared morphological parameters between rubble sampled from rubble mounds accumulated at the seaward side of artificial breakwaters and rubble sampled from a nearby location with no breakwaters (=control site). The purpose of this work was to establish a methodology for comparing the surface area and fractal complexity of coral rubble fragments using easily available equipment that could be efficiently utilized during field work. Rubble fragments were individually weighed and photographed in controlled light conditions. Each photograph was then analyzed using ImageJ software. Rubble pieces from each photograph went through segmentation, the separation of sample outlines from the picture background, before being measured and analyzed for surface area, width, and length (size estimators), and circularity, aspect ratio, roundness, solidity, and Feret properties (shape estimators). Surface fractal complexity was also measured, using the box counting method on segmented rubble surfaces. We observed lowered surface areas, weight, and fractal complexity for rubble fragments sampled at the breakwater. We demonstrate how this method could be used to compare coral rubble from a variety of environmental conditions, thus becoming a useful aid in environmental monitoring, in addition to adding important information to the collection and analyses of biological data.

Author(s):  
M. Marko ◽  
A. Leith ◽  
D. Parsons

The use of serial sections and computer-based 3-D reconstruction techniques affords an opportunity not only to visualize the shape and distribution of the structures being studied, but also to determine their volumes and surface areas. Up until now, this has been done using serial ultrathin sections.The serial-section approach differs from the stereo logical methods of Weibel in that it is based on the Information from a set of single, complete cells (or organelles) rather than on a random 2-dimensional sampling of a population of cells. Because of this, it can more easily provide absolute values of volume and surface area, especially for highly-complex structures. It also allows study of individual variation among the cells, and study of structures which occur only infrequently.We have developed a system for 3-D reconstruction of objects from stereo-pair electron micrographs of thick specimens.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jeongpil Kim ◽  
Jeong-Hyun Eum ◽  
Junhyeok Kang ◽  
Ohchan Kwon ◽  
Hansung Kim ◽  
...  

AbstractHerein, we introduce a simple method to prepare hierarchical graphene with a tunable pore structure by activating graphene oxide (GO) with a two-step thermal annealing process. First, GO was treated at 600 °C by rapid thermal annealing in air, followed by subsequent thermal annealing in N2. The prepared graphene powder comprised abundant slit nanopores and micropores, showing a large specific surface area of 653.2 m2/g with a microporous surface area of 367.2 m2/g under optimized conditions. The pore structure was easily tunable by controlling the oxidation degree of GO and by the second annealing process. When the graphene powder was used as the supercapacitor electrode, a specific capacitance of 372.1 F/g was achieved at 0.5 A/g in 1 M H2SO4 electrolyte, which is a significantly enhanced value compared to that obtained using activated carbon and commercial reduced GO. The performance of the supercapacitor was highly stable, showing 103.8% retention of specific capacitance after 10,000 cycles at 10 A/g. The influence of pore structure on the supercapacitor performance was systematically investigated by varying the ratio of micro- and external surface areas of graphene.


2021 ◽  
Vol 6 (2) ◽  
pp. 247301142110126
Author(s):  
Jeffrey Donahue ◽  
Ademola Shofoluwe ◽  
Kurt Krautmann ◽  
Emilio Grau-Cruz ◽  
Stephen Becher ◽  
...  

Background: Fractures of the talus are a rare but challenging injury. This study sought to quantify the area of osseous exposure afforded by a posteromedial approach to the talus and medial malleolar osteotomy. Methods: Five fresh-frozen cadaveric lower extremities were dissected using a posteromedial approach and medial malleolar osteotomy respectively. Following exposure, the talar surfaces directedly visualized were marked and captured using a calibrated digital image. The digital images were then analyzed using ImageJ software (National Institutes of Health) to calculate the surface area of the exposure. Results: The average square area of talus exposed using the posteromedial approach was 9.70 cm2 (SD = 2.20, range 7.20-12.46). The average quantity of talar exposure expressed as a percentage was 9% (SD = 1.58, range 7.03-10.40). The average square area of talus exposed using a medial malleolar osteotomy was 14.32 cm2 (SD = 2.00, range 11.26-16.66). The average quantity of talar exposure expressed as a percentage was 12.94% (SD = 1.79, range 9.97-14.73). The posteromedial approach provided superior visualization of the posterior talus, whereas the medial malleolar osteotomy offered greater access to the medial body. Conclusion: The posteromedial approach and medial malleolar osteotomy allow for significant exposure of the talus, yielding 9.70 and 14.32 cm2, respectively. Given the differing portions of the talus exposed, surgeons may prefer to use the posteromedial approach for operative fixation of posterior process fractures and elect to use a medial malleolar osteotomy in cases requiring more extensive medial and distal exposure for neck or neck/body fractures. Level of Evidence: Level IV.


2021 ◽  
Author(s):  
Atal Ahmadzai

Alerted by increasing water insecurity and energy demand, countries, mainly in the Global South, are building dams of unprecedented magnitude. Hundreds of large dams (≥ 100 metres) have been constructed since 2000, with hundreds more under construction. Analyses of the physical attributes of these dams present a concerning image. While they create expansive reservoirs with large surface areas, they have inefficient surface area-to-volume ratios ('S2VR'). Their unprecedented size and the reservoirs’ expansive surface area, indicate severe environmental costs, mainly through ecological disturbances to the (riverine) aquatic ecosystems; and greenhouse gas emissions (GHG). Other ecological costs due to the larger S2VR include a high evaporation rate and compromised biodiversity of a wider area, both up- and downstream. The safety and environmental aspects of these large dams should be robustly scrutinised.


2018 ◽  
Vol 8 (9) ◽  
pp. 1596 ◽  
Author(s):  
Jung Park ◽  
Gi Lee ◽  
Sang Hwang ◽  
Ji Kim ◽  
Bum Hong ◽  
...  

In this study, a feasible experiment on adsorbed natural gas (ANG) was performed using activated carbons (ACs) with high surface areas. Upgraded ACs were prepared using chemical activation with potassium hydroxide, and were then applied as adsorbents for methane (CH4) storage. This study had three principal objectives: (i) upgrade ACs with high surface areas; (ii) evaluate the factors regulating CH4 adsorption capacity; and (iii) assess discharge conditions for the delivery of CH4. The results showed that upgraded ACs with surface areas of 3052 m2/g had the highest CH4 storage capacity (0.32 g-CH4/g-ACs at 3.5 MPa), which was over two times higher than the surface area and storage capacity of low-grade ACs (surface area = 1152 m2/g, 0.10 g-CH4/g-ACs). Among the factors such as surface area, packing density, and heat of adsorption in the ANG system, the heat of adsorption played an important role in controlling CH4 adsorption. The released heat also affected the CH4 storage and enhanced available applications. During the discharge of gas from the ANG system, the residual amount of CH4 increased as the temperature decreased. The amount of delivered gas was confirmed using different evacuation flow rates at 0.4 MPa, and the highest efficiency of delivery was 98% at 0.1 L/min. The results of this research strongly suggested that the heat of adsorption should be controlled by both recharging and discharging processes to prevent rapid temperature change in the adsorbent bed.


2017 ◽  
Vol 2 (3) ◽  
pp. 2473011417S0001
Author(s):  
Ali Hosseini ◽  
Pim Van Dijk ◽  
Sofie Breuking ◽  
Bryan Vopat ◽  
Daniel Guss ◽  
...  

Category: Midfoot/Forefoot Introduction/Purpose: Proximal fifth metatarsal fractures (PFMF) are among the most common fractures in the foot and can be categorized into three fracture zones [1]. To investigate the fracture mechanism of PFMF in different zones, a better understanding of the anatomy of the bone and its surrounding soft tissues is required. Both the plantar fascia (PF) and the peroneus brevis (PB) tendon insertions are at the base of the fifth metatarsal, and may contribute to the pathophysiology of PFMF. However, the role of the PB and PF insertions in the pathogenesis of PFMF remains unclear. The purpose of this study was to accurately define the footprint of the PB and PF insertions of the base of the 5th metatarsal in relation to the different zones of PFMF. Methods: 21 cadaveric fifth metatarsal bones were harvested from cadaveric feet. All bones were freed of any remaining soft tissue adherence, except for the PB and the PF insertions. Three reference screws with a diameter of 1 mm were placed and secured on each bone with 2 screws distally and 1 screw proximally for registration. All bones were CT scanned to create a 3D bone reconstruction. Next, the insertions of the PB and PF and the reference screws of each bone were digitized and then mapped to its corresponding 3D bone model. In order to describe the three different fracture zones of the 5th metatarsal, an established coordinate system was made for each bone to simulate separate fracture zones (Figure a) based on Lawrence guideline [1]. The shape, location and surface areas of both insertions and their relation to the different fractures zones were determined (Figure b). Results: The insertion of the PB was oval shaped and located on the dorsal side of the base, with a mean surface area of 88.1 ± 46.4 mm2. The PF was oval shaped and situated around the tip of tuberosity, with a mean surface area of 150.7±53.5 mm2. The PB insertion was present in zone 1 fractures in 100% (21/21) of the 5th metatarsal models and 29% (6/21) of the models for zone 2 fractures. The PF insertion was involved in 100% (21/21) of the 5th metatarsal models for zone 1 fractures and 43% (9/21) of the models for zone 2 fractures. Conclusion: Results of this study demonstrate that the insertion of both the PB and PF are involved in all zone 1 PFMF and a significant percentage of zone 2 PFMF. The location of tendon insertions affect the forces exerted on the bone, which may indicate a relation of the insertions of both the PB and the PF with the fracture mechanism of many zone 1 and 2 PFMF. Moreover, in the treatment of these fractures, care should be taken to maintain or restore the anatomy of these insertions to maximize functional outcomes.


1968 ◽  
Vol 11 (4) ◽  
pp. 805-810 ◽  
Author(s):  
E. R. Nilo

Twelve young adult men with normal hearing and no history of ear disease took part in our study of the relation of vibrator surface area and static application force to the vibrator-to-head coupling. For vibrator surface areas of 1.125, 2.25, and 4.5 cm 2 coupled to the forehead under static forces of 150, 300, and 600 gm, monaural thresholds of bone-conduction hearing were determined at frequencies 250, 500, 1000, and 2000 Hz. With surface area constant, threshold improvement was frequency dependent. It decreased with increasing frequency until at 2000 Hz it was minimal. In contrast to this, with force constant, the influence of surface area was observed to begin at 2000 Hz. Preliminary study suggests this influence would extend to 4000 Hz. In view of the respective influence of application force and surface area to bone-conduction hearing, equating vibrator-to-head coupling on the basis of pressure (force per unit area), when there are two or more vibrators, may not represent an adequate control.


2021 ◽  
Vol 9 (4) ◽  
pp. 90-95
Author(s):  
A. A. Воробьев ◽  
Yu. A. Makedonova ◽  
A. O. Solov'ev ◽  
D. Yu. D'yachenko ◽  
E. G. Bagrii ◽  
...  

Relevance. The currently available methods for measuring anatomical areas with irregular relief do not claim to be accurate and easy to use.The aim of the study was to develop a method for measuring the surface area of an anatomical region (substructure) with an irregular relief.Material and methods. There was developed an option to measure the surface area of an anatomical region (substructure) with a complex relief in patients with pathology of the maxillofacial region and perineum using realistic 3D modeling.Results. The principle of the developed method is that, firstly, it is necessary to determine the patient's "zone of interest", where it is planned to measure the surface area; after that, digital photographs of the defined area are taken to obtain a sufficient number of images from the maximum number of available angles using a template with predefined dimensions for scaling. Then the obtained photographs are processed in the program for the 3D model reconstruction, and a realistic 3D model that correctly repeats the relief of the "zone of interest" and guarantees measurements of the surface area taking into account all its individual features is obtained. The method has been tested in obstetrics and gynecology, dentistry, maxillofacial surgery.Conclusion. This technique has been proved to be simple, accessible, fast, highly accurate in measuring the area of anatomical regions with complex relief. At the same time, the investigated object does not need fixation and prolonged immobility. A digital optical device is used contactless, the fact being significant in situations where it is necessary to comply with the rules of asepsis and antisepsis.


Author(s):  
Francisco Andres Rivera-Quiroz ◽  
Jeremy Miller

Traditional taxonomic publications have served as a biological data repository accumulating vast amounts of data on species diversity, geographical and temporal distributions, ecological interactions, taxonomic relations, among many other types of information. However, the fragmented nature of taxonomic literature has made this data difficult to access and use to its full potential. Current anthropogenic impact on biodiversity demands faster knowledge generation, but also making better use of what we already have. This could help us make better-informed decisions about conservation and resources management. In past years, several efforts have been made to make taxonomic literature more mobilized and accessible. These include online publications, open access journals, the digitization of old paper literature and improved availability through online specialized repositories such as the Biodiversity Heritage Library (BHL) and the World Spider Catalog (WSC), among others. Although easy to share, PDF publications still have most of their biodiversity data embedded in strings of text making them less dynamic and more difficult or impossible to read and analyze without a human interpreter. Recently developed tools as GoldenGATE-Imagine (GGI) allow transforming PDFs in XML files that extract and categorize taxonomically relevant data. These data can then be aggregated in databases such as Plazi TreatmentBank, where it can be re-explored, queried and analyzed. Here we combined several of these cybertaxonomic tools to test the data extraction process for one potential application: the design and planning of an expedition to collect fresh material in the field. We targeted the ground spider Teutamus politus and other related species from the Teutamus group (TG) (Araneae; Liocranidae). These spiders are known from South East Asia and have been cataloged in the family Liocranidae; however, their relations, biology and evolution are still poorly understood. We marked-up 56 publications that contained taxonomic treatments with specimen records for the Liocranidae. Of these publications, 20 contained information on members of the TG. Geographical distributions and occurrences of 90 TG species were analyzed based on 1,309 specimen records. These data were used to design our field collection in a way that allowed us to optimize the collection of adult specimens of our target taxa. The TG genera were most common in Indonesia, Thailand and Malaysia. From these, Thailand was the second richest but had the most records of T. politus. Seasonal distribution of TG specimens in Thailand suggested June and July as the best time for collecting adults. Based on these analyses, we decided to sample from mid-July to mid-August 2018 in the three Thai provinces that combined most records of TG species and T. politus. Relying on the results of our literature analyses and using standard collection methods for ground spiders, we captured at least one specimen of every TG genus reported for Thailand. Our one-month expedition captured 231 TG spiders; from these, T. politus was the most abundant species with 188 specimens (95 adults). By comparison, a total of 196 specimens of the TG and 66 of T. politus had been reported for the same provinces in the last 40 years. Our sampling greatly increased the number of available specimens, especially for the genera Teutamus and Oedignatha. Also, we extended the known distribution of Oedignatha and Sesieutes within Thailand. These results illustrate the relevance of making biodiversity data contained within taxonomic treatments accessible and reusable. It also exemplifies one potential use of taxonomic legacy data: to more efficiently use existing biodiversity data to fill knowledge gaps. A similar approach can be used to study neglected or interesting taxa and geographic areas, generating a better biodiversity documentation that could aid in decision making, management and conservation.


2011 ◽  
Vol 53 (3) ◽  
pp. 717-726 ◽  
Author(s):  
BAOCHENG ZHU ◽  
NI LI ◽  
JIAZU ZHOU

AbstractIn this paper, we establish a number of Lp-affine isoperimetric inequalities for Lp-geominimal surface area. In particular, we obtain a Blaschke–Santaló type inequality and a cyclic inequality between different Lp-geominimal surface areas of a convex body.


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