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Understanding the porosity of coke and how it changes during reaction is key for understanding coke reactivity and minimizing coke consumption in the blast furnace. The change in porosity of coke and coke analogue samples after reaction with CO2 is assessed using high‐resolution micro‐computer tomography (micro‐CT) scans. High‐resolution micro‐CT scans (2.35 μm voxel−1) are carried out before and after reaction with CO2 at 1100 °C. 3D micro‐CT measurements are validated against standard 2D measurements, and used to quantitatively assess the porosity evolution in the samples. The porosity and pore connectivity of the coke and analogue samples increase in reaction with CO2. Most of the increase in porosity occurs in the pores <60 μm. Inert maceral‐derived component (IMDC) regions in coke A are more reactive than reactive maceral‐derived component (RMDC) regions. This is possibly related to the higher proportion of fine pores in unreacted IMDC compared to RMDC. Characterization of larger coke and coke analogue samples using micro‐CT at lower resolution (9.65–16.72 μm voxel−1) allows the rate‐controlling mechanism to be determined as likely to be mixed control, with both chemical reaction and pore diffusion‐controlling reaction rate. This finding demonstrates that high‐ and lower‐resolution micro‐CT datasets should be considered complementary. [ABSTRACT FROM AUTHOR]

A coral reef is an underwater ecosystem characterized by stony corals and reef rubble. Reef rubble is formed by the aragonite and calcite skeletons of dead scleractinian corals and other calcareous organisms. In the ocean, reef rubble contributes to numerous benefits to the marine environment, including the formation of coral reefs, the provision of habitats for marine organisms, and the ability to withstand the impact of waves; reef rubble also plays an important role in saltwater aquaria. However, the transformation process from coral skeleton to reef rubble is poorly understood. This study reconstructed mineralised samples at three stages of the formation process and observed this transformation visually using high-resolution micro-computer tomography. In the binding and cementation processes during reef rubble formation, the content of high-Mg calcite increased in the calcareous samples, the gaps among adjacent sediments disappeared, and the skeleton-void ratio of coral skeletons decreased from 40–50% to 12%. The compressive strength of coral skeletons increased from 4–7 MPa to more than 40 MPa during reef rubble formation, and decreased to 1–2.5 MPa after bioerosion by barnacles. This work provides structural information for diagenetic changes, insight into barnacle erosion in coral skeletons, and extends our understanding of mechanical strength changes during reef rubble formation, which contributes to understand the rigidity of coral reefs. [ABSTRACT FROM AUTHOR]

The demand for bone grafting procedures in various fields of medicine is increasing. Existing substitutes in clinical practice do not meet all the criteria required for an ideal bone scaffold, so new materials are being sought. This study evaluated bone regeneration using a critical-size Wistar rat’s calvarial defect model. 12 male and 12 female rats were evenly divided into 3 groups: 1. Negative and positive (Geistlich Bio-Oss®) controls; 2. polylactic acid (PLA) and PLA/hydroxyapatite (HA); 3. PLA/HA cellularised with dental pulp stem cells (DPSC) and PLA/HA extracellular matrix (ECM) scaffolds. PLA/HA filament was created using hot-melt extrusion equipment. All scaffolds were fabricated using a 3D printer. DPSC were isolated from the incisors of adult Wistar rats. The defects were evaluated by micro-computed tomography (µCT) and histology, 8 weeks after surgery. µCT revealed that the Bio-Oss group generated 1.49 mm3 and PLA/HA ECM 1.495 mm3 more bone volume than the negative control. Histology showed a statistically significant difference between negative control and both (Bio-Oss and PLA/HA ECM) groups in rats of both genders. Moreover, histology showed gender-specific differences in all experimental groups and a statistically significant difference between cellularised PLA/HA and PLA/HA ECM groups in female rats. Qualitative histology showed the pronounced inflammation reaction during biodegradation in the PLA group. In conclusion, the bone-forming ability was comparable between the Bio-Oss and PLA/HA ECM scaffolds. Further research is needed to analyse the effects of ECM and PLA/HA ratio on osteoregeneration.

We present a morphological study of Indonesian sponge-inhabiting barnacles using standard light microscopy in combination with micro-CT scanning and computer-aided 3D-reconstruction of the external shell morphology. A taxonomic analysis of the material detected four different genera of sponges inhabited by five different species of balanomorph barnacles, two of which are undescribed. Together with conventional morphological examination by dissection, we provide modern nondestructive imaging methods, using micro-CT scanning to enhance our knowledge of the morphological characters of sponge-inhabiting barnacles from eastern Indonesia. Although there were some methodological limitations regarding the contrast-enhancing technique, this study demonstrates micro-CT as a useful non-destructive technique of integrative taxonomy, for the examination of sponge-inhabiting barnacles. [ABSTRACT FROM AUTHOR]

As mining depth increases, the backfill mining method is more and more widely used in underground mines. The dynamic load generated by the blasting can affect the stability of the cemented tailings backfill (CTB). The CTB samples were prepared to conduct a test of the split Hopkinson pressure bar (SHPB) to investigate the dynamic disturbance of CTB. The present paper discusses dynamical mechanics, energy dissipation, and microstructure analysis of CTB. Micro-computer tomography (micro-CT) scanning of CTB samples after the SHPB test was performed to analyze the evolution of internal cracks. The experimental results showed that when the average strain rate (ASR) increased from 30 to 98 s−1, the dynamic uniaxial compression strength (DUCS) of the CTB showed a trend of first increasing and decreasing with the increase in ASR. The dynamic stress–strain pre-peak curve of CTB directly enters the linear elastic stage. As ASR increases, the absorbed energy of the CTB shows a trend of first increasing and then decreasing. Moreover, according to the micro-CT scanning results, the crack area of CTB accounts for about 16% of the sample near the incident bar and about 1% near the transmitted bar. The crack area ratio is exponentially related to the specimen height. These findings can provide reasonable dynamical CTB strength data selection for underground pillar mining.

[Display omitted] • We have used Micro CT technology to describe the tracheal anatomy of the common wasp. • Recently recommended nomenclature has been used to describe the tracheal anatomy. • Despite being apparently healthy, one wasp had a markedly different looking tracheal system. • These techniques might usefully be extended to genetic studies of smaller fruit flies. X-ray micro-CT has been used to study the tracheal system of Pre and Post hibernation Queen wasps (Vespula vulgaris) and their workers. We have compared our findings in wasps with Snodgrass's description of the tracheal system of the honeybee as characterised by anatomical dissection. Our images, whilst broadly similar, identify the tracheal system as being considerably more complex than previously suggested. One of the 30 wasps imaged had a markedly different, previously undescribed tracheal system. Since completing this study, a large micro-CT study from the American Museum of Natural History (AMNH) has been published. This used different software (Slicer) and analysed 16bit digital data. We have compared our methods with that described in the AMNH publication, adopted their suggested nomenclature and have made recommendations for future studies. [ABSTRACT FROM AUTHOR]

Fused Deposition Modelling (a.k.a. FDM-3D printing) has been previously employed in the development of personalized medicines with unique properties and release behavior. In the present work, a bilayer dosage form containing two anti-diabetic drugs with different daily dosage regimens; i.e. metformin and glimepiride, was manufactured via FDM 3D printing, studied using a variety of techniques and characterized in vitro. Metformin and glimepiride were embedded in Eudragit® RL sustained release layer and polyvinyl alcohol (PVA) layer respectively. Incorporation of more than one API's into the formulation is desirable, as it increases patient compliance and reduces cost of treatment, especially when distinct dosages of API's can be adjusted individually in situ, in order to meet each patient's specific needs, a capability provided by 3D printing. A number of different preparation methods, which involved different plasticizers and extruders, were tested on manufacturing Eudragit® RL drug-loaded filaments for printing the sustained release layer. The properties of the produced filaments were assessed by means of mechanical and physicochemical characterization techniques and the filaments with the optimum properties were used for printing. Microfocus computed tomography (μCT) imaging-based actual/nominal comparison analysis showed a printing accuracy ranging between −100, +200 μm, while X-ray (XRD) diffractograms revealed the incorporation of the (initially crystalline) API's as amorphous dispersions into polymer matrices. Dissolution tests showed sufficient drug release for both drugs in desired time frames (75 min for glimepiride and 480 min for metformin). The results from the current study emphasize the potentiality of 3D printing technology for tailor-made solid dosage forms for combined pharmacotherapy, even at the cases when API's with different desirable release profiles are employed. [ABSTRACT FROM AUTHOR]

Neurological degeneration can occur after compression of the spinal cord. It is widely accepted that spinal cord compression leads to ischemic lesions and ultimately neurological dysfunction due to a narrowed spinal canal. Therefore, an in-depth understanding of the pathogenesis of spinal cord compression injury is required to help develop effective clinical interventions. In the present study, we propose a new method of quantitative 3D micro-CT to observe microvascular events in a chronic spinal cord compression rat model. A total of 36 rats were divided into two groups: sham control group (n = 12) and compressive spinal cord injury group (n = 24). Rats were scarified at four weeks after surgery. In each group, CD34 micro-vessel immunohistochemical staining was performed in half of the animals, while micro-CT scanning was performed in the other half. Microvessel density (MVD) was measured after immunohistochemical staining, while the vascular index (VI) was measured in 3D micro-CT. In comparison with sham control, abnormal somatosensory evoked potentials (SEP) can be seen in all 24 cases of the compression group, and VI shows the amount of microvessels reduced consistently and significantly (p < 0.01). A significant correlation is also found between MVD and VI (r = 0.95, p < 0.01). These data suggest that quantitative 3D micro-CT is a sensitive and promising tool for investigating microvascular changes during chronic compressive spinal cord injury.

Accurate determination of the petrophysical properties of rocks, namely REV, mean pore and grain size and absolute permeability, is essential for a broad range of engineering applications. Here, the petrophysical properties of rocks are calculated using an integrated approach comprising image processing, statistical correlation and numerical simulations. The Stokes equations of creeping flow for incompressible fluids are solved using the Finite-Volume SIMPLE algorithm. Simulations are then carried out on three-dimensional digital images obtained from micro-CT scanning of two rock formations: one sandstone and one carbonate. Permeability is predicted from the computed flow field using Darcy's law. It is shown that REV, REA and mean pore and grain size are effectively estimated using the two-point spatial correlation function. Homogeneity and anisotropy are also evaluated using the same statistical tools. A comparison of different absolute permeability estimates is also presented, revealing a good agreement between the numerical value and the experimentally determined one for the carbonate sample, but a large discrepancy for the sandstone. Finally, a new convergence criterion for the SIMPLE algorithm, and more generally for the family of pressure-correction methods, is presented. This criterion is based on satisfaction of bulk momentum balance, which makes it particularly useful for pore-scale modelling of reservoir rocks. [ABSTRACT FROM AUTHOR]

Parasitic barnacles (Cirripedia: Rhizocephala) are highly specialized parasites of crustaceans. Instead of an alimentary tract for feeding they utilize a system of roots, which infiltrates the body of their hosts to absorb nutrients. Using X-ray micro computer tomography (MicroCT) and computer-aided 3D-reconstruction, we document the spatial organization of this root system, the interna, inside the intact host and also demonstrate its use for morphological examinations of the parasites reproductive part, the externa. This is the first 3D visualization of the unique root system of the Rhizocephala in situ, showing how it is related to the inner organs of the host. We investigated the interna from different parasitic barnacles of the family Peltogastridae, which are parasitic on anomuran crustaceans. Rhizocephalan parasites of pagurid hermit crabs and lithodid crabs were analysed in this study. [ABSTRACT FROM AUTHOR]

Mechanical properties of short-fiber reinforced composites are crucially influenced by their microstructure. The microstructure itself is mainly governed by the manufacturing process like injection or compression molding. The main contribution of this paper lies in the homogenization of linear elastic properties using experimental microstructural information. For this purpose, the microstructure of injection-molded specimens made of polypropylene reinforced with 30wt.% of short glass fibers are analyzed through micro-computer tomography (μCT) measurements. Applying a recently developed segmentation algorithm, the spatial position, the orientation distribution and the length of the fibers are determined. This data is evaluated in terms of orientation tensors and length distribution, and is used within three mean field approaches: a self-consistent homogenization method, the interaction direct derivative estimate, which is based on the three-phase model, and a two-step bounding method. All methods account for the orientation, the length and the diameter distribution. The numerical results are compared to experimental tensile tests. [ABSTRACT FROM AUTHOR]

A new bipinnate fertile pinna, Sterzelitheca chemnitzensis , bearing alternate synangia, is described from the Chemnitz Petrified Forest, Germany. The specimen occurs in the basal volcanic ash of the Zeisigwald Tuff Horizon, Leukersdorf Formation, Lower Permian. Because it is partially embedded in the tuffaceous matrix, X-ray micro-computer tomography was employed to investigate the complete morphology without mechanical preparation of the hand specimen. The pinna is 66 mm long and branched once at least, the ultimate pinnae alternately positioned on the penultimate axis at angles of 45–55°. Stalked synangia are bell-like, borne alternately on both the terminal portion of the penultimate axis and the ultimate axes at angles of 25–60°. The smooth walled stalk is 3–7 mm long, 1–1.5 mm wide. Individual synangia are up to 6.5 mm in diameter and 10 mm long, and bear 12–14 elongated sporangia. Tubular sporangia are thin walled, circular in transverse section, arranged at the rim of the circular synangial pad around a central hollow. The unique preservational mould of the studied specimen is neither a permineralisation nor a compression–impression. It is three-dimensionally preserved, but lacks any organic remains. We provide the first detailed three-dimensional features of a probable medullosan male reproductive organ from the Chemnitz Fossil Lagerstätte. The relatively simple structure of the specimen offers a better understanding of the Palaeozoic seed ferns. [ABSTRACT FROM AUTHOR]

• A novel nano silica fume was studied with particle size distribution between silica fume and nano silica. • A quantitative relationship between the water-to-cement ratio, solid volume fraction and the nano silica fume content was established. • A reference for the application of nano silica fume in the field of cementation was given. The aim of this study is to investigate the effect of nano silica fume (NSF) on the physical properties and microstructural characteristics of lightweight cement slurry (LWCS) with a high solid volume fraction (SVF) above 45%. The slurries were prepared with various contents of NSF (0%, 5%, 10%, 15%, 20%, 30%). A series of tests were conducted to determine the rheological properties, compressive strength, settlement stability and uniformity. The reaction products and microstructures were characterized through XRD, SEM, micro-CT. Furthermore, the properties of pores of hardened cement stone, such as the fractal dimension of pores, were also analyzed based on micro-CT to track the influence of nano silica fume on the specimens. The results revealed that the incorporation of NSF significantly improved the compressive strength and the microstructural of LWCS. The improvement in strength resulted from the pozzolanic effect, filling effect and nucleation effect of NSF. NSF consumes portlandite to form more calcium silicate hydrate, acts as a filler to fill the empty space, provides nucleation sites for cement hydration, and finally makes the internal structure of the LWCS denser. Moreover, the water-to-cement ratio (w/c) and the SVF of LWCS both have a linear correlation with the content of NSF in LWCS. [ABSTRACT FROM AUTHOR]

Abstract: This study examines the properties of calcifying human costal cartilage and adjacent rib bone using qualitative and quantitative micro-computed tomography analysis. Calcifications are categorized with respect to location, microstructure, shape, and contiguity using a novel classification scheme and quantified in terms of mineral density, volume fraction, and length of infiltration from the costo-chondral junction (CCJ). Calcifications were present throughout the cartilage by location and ranged from small diffuse calcifications to nodes, rods, plates, and even large complex structures that exhibited a microstructural morphology similar to a cross-section of diaphysial bone, with a dense shell surrounding a trabecular core. Solid microstructure was most common for calcifications (44.5%), and the morphologies were found to vary with location, with rods and plates being most prevalent at the periphery (91.7% of all rods, 98.4% of all plates). The average mineral density of the calcifications over all locations and morphologies was 658.8±86.36, compared with 662.7±50.37mgHAcm−3 for the adjacent rib bone. The calcification volume fraction (6.54±4.71%) was less than the volume fraction of rib bone (21.62±6.44%). The length of contiguous calcification infiltrating from the CCJ into the costal cartilage, when present, was 19.21±11.65mm. These changes in the costal cartilage should be considered in biomechanical models of the thorax since the presence, location, and morphology of the calcifications alter the material behavior of the costal cartilage, as well as the structural behavior of the entire rib. [Copyright &y& Elsevier]

Although the murine thoracic aorta and its main branches are widely studied to gain more insight into the pathogenesis of human vascular diseases, detailed anatomical data on the murine aorta are sparse. Moreover, comparative studies between mice and men focusing on the topography and geometry of the heart and aorta are lacking. As this hampers the validation of murine vascular models, the branching pattern of the murine thoracic aorta was examined in 30 vascular corrosion casts. On six casts the intrathoracic position of the heart was compared with that of six younger and six older men of whom contrast-enhanced computer tomography images of the thorax were three-dimensionally reconstructed. In addition, the geometry of the human thoracic aorta was compared with that of the mouse by reconstructing micro-computer tomography images of six murine casts. It was found that the right brachiocephalic trunk, left common carotid artery and left subclavian artery branched subsequently from the aortic arch in both mice and men. The geometry of the branches of the murine aortic arch was quite similar to that of men. In both species the initial segment of the aorta, comprising the ascending aorta, aortic arch and cranial/superior part of the descending aorta, was sigmoidally curved on a cranial/superior view. Although some analogy between the intrathoracic position of the murine and human heart was observed, the murine heart manifestly deviated more ventrally. The major conclusion of this study is that, in both mice and men, the ascending and descending aorta do not lie in a single vertical plane (non-planar aortic geometry). This contrasts clearly with most domestic mammals in which a planar aortic pattern is present. As the vascular branching pattern of the aortic arch is also similar in mice and men, the murine model seems valuable to study human vascular diseases. [ABSTRACT FROM AUTHOR]

• All stages of Calliphora vomitoria contained large amounts of calcium-rich concretions packed tightly in the anterior Malpighian tubules. • Concretions can be used as marking agents to delineate developmental stages of the Malpighian tubules. • MicroCT can now show the crucial phase when the Malpighian tubules reconnect with the hind gut during pupation in C. vomitoria. • MicroCT research on C. vomitoria can be useful for studying renal tract development and urolithiasis in humans. Malpighian tubules are the insect equivalent of mammalian kidneys and normally drain into the gut at the junction between the mid and hind gut. The Malpighian tubules of the fruit fly Drosophila melanogaster are increasingly being used as a model for studying human renal tract development, histology, nephrolithiasis and urolithiasis. In the present study we report when using X-ray micro-computer tomography techniques, the larval, intrapuparial and adult stages of the larger Calliphora vomitoria can contain large amounts of calcium-rich concretions which are tightly packed in the lumen of both anterior Malpighian tubules. We show that it is feasible to utilise these calcium-rich concretions as a form of marking agent to delineate the various developmental stages of the Malpighian tubules including the crucial phase when the Malpighian tubules reconnect with the hind gut. In the majority of cases during the intrapuparial period the ureters of the Malpighian tubules did not start to re-canalise and thus reconnect with the developing hind gut until the 7th day of the 10-11 day. Just prior to ecdysis, virtually all the radio-opaque concretions in the Malpighian tubules had emptied into the hind gut and had then been completely excreted by the time the imago emerged from its puparium. In contrast, we show that in flies developing from larvae previously stained by ingesting Rhodamine B, a known substrate for both the Multi Xenobiotic Resistance and Multi Drug Resistant membrane transport systems, the efficiency with which these calcium-rich concretions are excreted by the imago as it emerges from its intrapuparial period can be significantly impaired. Therefore, it might be useful to include C. vomitoria as a model when studying renal tract development and urolithiasis using X-ray micro-computer tomography. [ABSTRACT FROM AUTHOR]

Porous poly(L-lactic acid) (PLA) scaffolds of 85 per cent and 90 per cent porosity are prepared using polymer sintering and porogen leaching method. Different weight fractions of 10 per cent, 30 per cent, and 50 per cent of hydroxyapatite (HA) are added to the PLA to control the acidity and degradation rate. The three-dimensional (3D) morphology and surface porosity are tested using micro-computer tomography (micro-CT), optical microscopy, and scanning electron microscopy (SEM). Results indicate that the surface porosity does not change on the addition of HA. The micro-CT examinations show a slight decrease in the pore size and increase in the wall thickness accompanied by reduced anisotropy for the scaffolds containing HA. Scanning electron micrographs show detectable interconnected pores for the scaffold with pure PLA. Addition of the HA results in agglomeration of the HA particles and reduced leaching of the porogen. Compression tests of the scaffold identify three stages in the stress--strain curve. The addition of HA results in a reduction in the modulus of the scaffold at the first stage of elastic bending of the wall, but this is reversed for the second and third stages of collapse of the wall and densification in the compression tests. In the scaffolds with 85 per cent porosity, the addition of a high percentage of HA could result in 70 per cent decrease in stiffness in the first stage, 200 per cent increase in stiffness in the second stage, and 20 per cent increase in stiffness in the third stage. The results of these tests are compared with the Gibson cellular material model that is proposed for prediction of the behaviour of cellular material under compression. The pH and molecular weight changes are tracked for the scaffolds within a period of 35 days. The addition of HA keeps the pH in the alkaline region, which results in higher rate of degradation at an early period of observation, followed by a reduced rate of degradation later in the process. The final molecular weight is higher for the scaffolds with HA than for scaffolds of pure PLA. The manufactured scaffolds offer acceptable properties in terms of the pore size range and interconnectivity of the pores and porosity for non-load-bearing bone graft substitute; however, improvement to the mixing of the phases of PLA and HA is required to achieve better integrity of the composite scaffolds. [ABSTRACT FROM AUTHOR]

Abstract: Synchrotron radiation micro-computer tomography (SRμCT) offers the possibility to investigate biomineralized structures in high detail. Two animals of adult medaka fish (Oryzias latipes) were analyzed by SRμCT with a resolution of 6.55μm: the wild-type animal was normally developed whereas the second animal showed an idiopathic deformation of the cranial and axial skeleton. These deformations could be followed on the macro- and on the microscale (i.e., on the level of the individual ribs and fin bones). Our study clearly demonstrates that SRμCT is an excellent technique to study alterations in the skeletal structure of fish in detail. [Copyright &y& Elsevier]

Porous objects of carbonated apatite were prepared by mixing polyvinyl alcohol fibres (PVA) and sodium chloride as porogens with nanocrystalline carbonated apatite powder. After cold isostatic pressing (CIP) and dissolving the porogens, the bioceramic showed an interconnecting porosity with pore diameters in the range of 250–400 μm. The method can be transposed to any material that is insoluble in water (like many polymers). Such objects are promising for bone regeneration because the interconnecting porosity in carbonated apatite provides a good environment for bone attachment and ingrowth. [Copyright &y& Elsevier]

The distribution of pore-fracture structure in coal directly affects the storage and migration characteristics of fluids. Simultaneously, under the condition of high buried depth, the coal structure is further changed by the temperature-pressure coupling. To study the pore size distribution of coal and the deformation characteristics of different pore-fracture structures under temperature-pressure coupling conditions, six different coal structure models are constructed using three-dimensional computer tomography reconstruction in this work. The box-counting algorithm is used to calculate the fractal dimensions of the pore-fracture structure and pore clusters in different pore sizes of coal. In the meantime, the fractal characteristics of the pore structure in different pore sizes are analyzed. Based on the coal structure model, a linear elastic deformation model under the temperature-pressure coupling is constructed. Moreover, the relationship of porosity and fractal dimension with the deformation of models is studied. The research results show that the porosity positively correlated with fractal dimension. The changes of pore volume fraction and fractal dimension in each pore size distribution range are consistent. Under the temperature-pressure coupling condition, both the model porosity and fractal dimension exhibit a quadratic function relationship with deformation. The deformation analysis of the three-dimensional models and two-dimensional cross-sections show that as the porosity and fractal dimension increase, the coal body deformation exhibits a trend of first decreasing and subsequent increasing. Low fractal dimension and high porosity could increase the model deformation. The research results can afford a theoretical basis for the study of coal structure characteristics under complex conditions. • The fractal structure models in different aperture range are constructed. • A temperature-pressure coupling model of coal microstructure is established. • The relationship between the pore-fracture structure and deformation is analyzed. [ABSTRACT FROM AUTHOR]

As mining depth increases, the backfill mining method is more and more widely used in underground mines. The dynamic load generated by the blasting can affect the stability of the cemented tailings backfill (CTB). The CTB samples were prepared to conduct a test of the split Hopkinson pressure bar (SHPB) to investigate the dynamic disturbance of CTB. The present paper discusses dynamical mechanics, energy dissipation, and microstructure analysis of CTB. Micro-computer tomography (micro-CT) scanning of CTB samples after the SHPB test was performed to analyze the evolution of internal cracks. The experimental results showed that when the average strain rate (ASR) increased from 30 to 98 s−1, the dynamic uniaxial compression strength (DUCS) of the CTB showed a trend of first increasing and decreasing with the increase in ASR. The dynamic stress–strain pre-peak curve of CTB directly enters the linear elastic stage. As ASR increases, the absorbed energy of the CTB shows a trend of first increasing and then decreasing. Moreover, according to the micro-CT scanning results, the crack area of CTB accounts for about 16% of the sample near the incident bar and about 1% near the transmitted bar. The crack area ratio is exponentially related to the specimen height. These findings can provide reasonable dynamical CTB strength data selection for underground pillar mining. [ABSTRACT FROM AUTHOR]

The filamentous ascomycete fungus Aspergillus niger is a prolific secretor of organic acids, proteins, enzymes and secondary metabolites. Throughout the last century, biotechnologists have developed A. niger into a multipurpose cell factory with a product portfolio worth billions of dollars each year. Recent technological advances, from genome editing to other molecular and omics tools, promise to revolutionize our understanding of A. niger biology, ultimately to increase efficiency of existing industrial applications or even to make entirely new products. However, various challenges to this biotechnological vision, many several decades old, still limit applications of this fungus. These include an inability to tightly control A. niger growth for optimal productivity, and a lack of high-throughput cultivation conditions for mutant screening. In this mini-review, we summarize the current state-of-the-art for A. niger biotechnology with special focus on organic acids (citric acid, malic acid, gluconic acid and itaconic acid), secreted proteins and secondary metabolites, and discuss how new technological developments can be applied to comprehensively address a variety of old and persistent challenges., (© 2021 The Author(s).)

Female reproductive systems are important characters for understanding the evolution of Brachyura and resolving its phylogenetic relationships. We herein investigate a podotreme brachyuran reproductive system comprehensively for the first time studying spermathecae and gonopores of Homoloidea with histological methods, micro-computer tomography and scanning electron microscopy. Our results show that spermathecal apertures are species-specific and their shape corresponds closely to that of male copulatory organs. Apertures were either enclosed by membranous cuticle areas or otherwise occluded preventing direct access into spermathecae. 3D-reconstructions reveal that spermathecae differ between the species Paromola cuvieri and Homola barbata with regard to the involvement of sternite 7 and 8, respectively, in forming the sperm storage chamber. The cuticle epithelium that lines the spermathecal chamber is irregular and distinct from the remaining cylindrical cuticle epithelium. A first uniramous pleopod was present in all homoloids studied and always held in a position to cover spermathecal apertures. Specific pulvinated cuticle structures present on both sides of the first pleopod are herein interpreted as adhesive structures functioning in reproductive processes. The coxal gonopores were enclosed by a laterally arising muscular mobile operculum that resembles opercula described in eubrachyuran vaginae, which raises the question whether these two structures are homologous. Our results are compared with data available for other brachyuran groups and discussed in terms of phylogenetic relationships within the Brachyura and possible functions in insemination and fertilization in Podotremata. J. Morphol. 278:89-105, 2017. ©© 2016 Wiley Periodicals,Inc., (© 2016 Wiley Periodicals, Inc.)

The dentition of lamniforme sharks exhibits several characters that have been used extensively to resolve the phylogenetic relationships of extant taxa, yet some uncertainties remain. Also, the development of different teeth of a tooth file within the jaws of most extant lamniforms has not been documented to date. High-resolution micro-computed tomography is used here to re-evaluate the importance of two dental characters within the order Lamniformes, which were considered not to be phylogenetically informative, the histotype and the number of teeth per tooth file. Additionally, the development and mineralization patterns of the teeth of the two osteodont lamniforms Lamna nasus and Alopias superciliosus were compared. We discuss the importance of these dental characters for phylogenetic interpretations to assess the quality of these characters in resolving lamniform relationships. The dental characters suggest that (1) Lamniformes are the only modern-level sharks exhibiting the osteodont histotype, (2) the osteodont histotype in lamniform sharks is a derived state in modern-level sharks (Elasmobranchii), (3) the osteodont type, conversely is convergently achieved when the clade Chondrichthyes is considered and thus might comprise a functional rather than a phylogenetic signal, and (4) there is an increase in the number of teeth per file throughout lamniform phylogeny. Structural development of the teeth of L. nasus and A. superciliosus is congruent with a previous investigation of the lamniform shark Carcharodon carcharias. J. Morphol. 277:1584-1598, 2016. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)