Fragment Size Distribution Research Articles

Prediction of rock fragmentation in the Boukhadra’s mine conditions

Purpose. The objective of the study consists in obtaining better quality rock fragmentation by using inclined holes to ensure good energy distribution and better stability of the upper wall.The Kuz-Ram model and the Langefors method are best suited to achieve the goal. Methodology. The study compares the blasting plan adopted by the Boukhadra mine located in the Wilaya of Tebessa, with that calculated by the Langefors method while using inclined holes. We chose the Kuz-Ram model as a simulation model and validation for the following reasons. Findings. The application of the proposed method of Langefors gave a satisfactory result in terms of process efficiency, the Kuz-Ram model predicts a significant reduction in the rate of oversized blocks using an inclined hole drilling technique, from 13.1 to 5.3 %. This approach appears to improve the degree of fragmentation, reduce the percentage of oversized blocks and decrease energy loss during blasting. Originality. Rock fragmentation, which corresponds to the size distribution of fragments of the blasted rock, is one of the most important indices for estimating the effectiveness of blasting works where the size of the fragments of the blasted pile plays an important role in efficient transportation, crushing and grinding.The size of the fragments depends on the characteristics of the rock mass, the type of explosive used, and the drilling and blasting pattern. Practical value. The use of inclined holes is an important technique to optimize rock fragmentation in open pit mines. The inclination can be adjusted to improve the direction and distribution of blast energy, which contributes to more efficient and uniform fragmentation of extracted rocks.

Evaluation of cfDNA fragmentation characteristics in plasma for the diagnosis of lung cancer: A prospective cohort study.

Lung cancer is one of the most prevalent cancers worldwide, yet only approximately 16% of patients are diagnosed in early stage, highlighting the urgent need for novel, highly accurate detection models. In our study, patients with suspected lung cancer or lung disease, as identified through radiographic imaging, along with healthy individuals, were consecutively recruited from Beijing Chest Hospital. Circulating free DNA (cfDNA) was extracted from plasma samples, and low-depth whole-genome sequencing was performed to identify fragmentomic features for model construction. A total of 265 participants were prospectively enrolled, comprising 124 lung cancer patients and 141 noncancer individuals. The model we developed was based on four cfDNA fragmentation characteristics, including 20-bp breakpoint nucleotides motif, fragmentation size coverage, fragmentation size distribution, and copy number variation. In an independent test cohort, the model achieved an area under the curve (AUC) of 0.861 (95% CI: 0.781-0.942) and demonstrated a sensitivity of 70% (95% CI: 53.5%-83.4%) at a specificity of 89.4% (95% CI: 76.9%-96.5%). Notably, the model was also effective in detecting early-stage cancer, with an AUC of 0.808 (95% CI: 0.69-0.925). In summary, our lung cancer detection model shows strong screening capabilities by leveraging four cfDNA fragmentation characteristics, exhibiting robust performance in early cancer diagnosis.

Development of a novel computational technique to create DNA and cell geometrical models for Geant4-DNA

BackgroundThis study aimed to develop a novel human cell geometry for the Geant4-DNA simulation toolkit that explicitly incorporates all 23 chromosome pairs of the human cell. This approach contrasts with the existing, default human cell, geometrical model, which utilizes a continuous Hilbert curve. MethodsA Python-based tool named “complexDNA” was developed to facilitate the design of both simple and complex DNA geometries. This tool was employed to construct a human cell geometry with individual pairs of chromosomes. Subsequently, the performance of this chromosomal model was compared to the standard human cell model provided in the “molecularDNA” Geant4-DNA example. ResultsSimulations using the new chromosomal model revealed minimal discrepancies in DNA damage yield and fragment size distribution compared to the default human cell model. Notably, the chromosomal model demonstrated significant computational efficiency, requiring approximately three times less simulation time to achieve equivalent results. ConclusionsThis work highlights the importance of incorporating chromosomal structure into human cell models for radiation biology research. The “complexDNA” tool offers a valuable resource for creating intricate DNA structures for future studies. Further refinements, such as implementing smaller voxels for euchromatin regions, are proposed to enhance the model’s accuracy.

Quantification of energy consumed in simulated percussive drilling process using dynamic indentation experiment

The high cost of drilling deep wells is the main barrier to the widespread exploitation of deep geothermal energy. Percussive drilling is one of the significant drilling technologies used in energy exploration projects. However, there is no good quantitative understanding of how much energy in percussive drilling is consumed in pulverization, heating, the kinetic energy of particles, acoustic emission, etc. In this study, energy efficiency is quantitatively investigated to understand the percussive drilling process better. The dynamic percussive drilling was evaluated using a modified split Hopkinson pressure bar (SHPB) system and non-contact measurements. The amount of energy dissipated in different processes and the overall energy efficiency was estimated for Kuru granite, Balmoral granite, and Kivijärvi gabbro. The energy spent on the kinetic energy Ek of fragments was evaluated using a high-speed camera, whereas the energy consumed on heat or the thermal energy Et was obtained by high-speed infrared imaging. The cracking energy Ec was measured by using the surface energy of rock and the total newly created surface areas. The results indicate that the fragment size distribution of these three rocks generally varies with the penetration speed, and the fragmentation level of these rocks increases with the penetration speed. The input energy and the energy consumption grow with the increase of the penetration speed. The proportions of Et, Ek, and Ec in the total energy consumption for these three rocks increase with the penetration speed. The energy efficiency obtained from the dynamic indentation experiments for the three rocks generally increases with the penetration speed and almost approaches a limit value when the penetration speed is high. A model is improved to describe the relationship between energy efficiency and penetration speed quantitatively. Therefore, the penetration process should be optimized to balance the high drilling efficiency and the low energy consumption.

B-025 Revolutionizing NGS-driven Laboratory Developed Tests: The impact of automated liquid handling on plate-based bead clean-up

Abstract Background Automated liquid handling systems are proving to be a transformative technology in the landscape of Laboratory Developed Tests (LDTs), especially those utilizing Next-Generation Sequencing (NGS). By enhancing accuracy, boosting efficiency, and offering scalable solutions, these systems enable labs to meet current and future challenges more effectively. The right system not only improves the quality of diagnostics but also positions labs to be agile and adaptive in a rapidly advancing healthcare environment. firefly® is a well-suited liquid handling solution for diagnostics labs developing LDTs due to its compact footprint, user-friendly software and exceptional versatility. Validated protocol templates that support NGS library preparation are readily available from the firefly cloud and can be adapted to meet specific lab needs. For example, automated bead-based clean-ups designed for 96- and 384- NGS applications are available on firefly. These remove DNA fragments of undesirable sizes, enzymes or primers rom the amplified DNA after a PCR reaction. Automating this process facilitates higher throughput and scaling. firefly has a unique combination of 6 positive displacement dispense heads and a 96/384-well air-displacement pipetting head, making it ideal to distribute the reagents required for bead clean-ups. Methods firefly protocols were developed and optimized to be compatible with a range of elution volumes and bead ratios. Protocol performance was tested using library DNA (∼300bp). The same input DNA was plated out and quantified using the QuantiFluor dsDNA system (Promega) before and after running the protocol. This data was used to assess any reduction in DNA concentration and uniformity across the plate. The protocol's ability to successfully modulate the fragment size distribution was demonstrated using a 50bp DNA ladder and different bead ratios. Data was obtained using a Fragment Analyzer (Agilent, DNF-474 HS NGS Fragment Kit). Well-to-well contamination was assessed by running no-template-controls (NTCs) in wells adjacent to library DNA, then analyzed by qPCR using a LightCycler 480 System (Roche, KAPA Library Quantification kit). Results 96 format has a setup time of 10 minutes, run time of 43 and %CV library concentration of <6%. 384 format has a setup time of 10 minutes, run time of 47 and %CV library concentration of <8%. Uniformity of concentration and fragment sizes was seen across the plates. Comparison of the library concentration before and after the clean-up showed a 5% reduction in DNA concentration after the 96-well plate clean-up and an 11% reduction in library concentration when using the 384-well plate clean-up. Fragment size analysis showed that fragment sizes can be successfully modulated on firefly by changing the bead ratio of the firefly run and no detectable well-to-well contamination was detected by qPCR. Conclusions We have demonstrated that automated bead clean-ups on firefly are uniform show uniformity across both 96- and 384-well plates, with no detectable well-to-well contamination, to deliver the consistent and robust results required for an LDT. Bead-based cleanups on firefly offer a fast, 100% walkaway solution. By running 96-samples at once on firefly, we see approximately a 6-fold increase in throughput than when performed manually by a single user.

Experimental and numerical investigation on rock fracturing and fragmentation under coupled static pressure and blasting

The blasting technique is widely adopted to break rock in civil and mining engineering, and its operation is generally subjected to static pressure due to tectonic and gravitational stresses. In the present study, the rock fracturing and fragmentation under coupled static pressure (uniaxial pressure and confining pressure) and blasting are experimentally and numerically investigated. First, 11 blast tests with 100-mm cubic red sandstone samples are carried out based on a biaxial loading system. Then, the blast-produced rock fragmentation in blast testing is numerically modeled using finite element method with LS-DYNA, and the explosion pressure attenuation and fracture evolution in rock samples are numerically reproduced. The simulated rock fragmentation data are obtained by image processing in ImageJ, and the fragment size distribution of red sandstone under combined static stress and blasting is characterized using Weibull distribution. Accordingly, the effects of uniaxial pressure and confining pressure on blast-created rock fragmentation are quantitatively compared and analyzed, and the corresponding mechanisms are discussed and revealed. The current findings indicate that the static pressure plays a role in increasing blast-induced compressive stress and reducing tensile stress in both radial and hoop directions and thus results in a decrease in the length and number of fractures propagating vertically to the direction of applied pressure, further leading to the creation of coarser fragmentation. Blasting under confining pressure produces larger fragments than that under uniaxial pressure. The average fragment size increases quickly at first and then increases slowly with the increase of static stress, which can be well characterized using a logarithm equation. Based on current findings, increasing the free surface is crucial in practical blasting to improve rock fragmentation performance under blasting.

Influence of blasting charge distribution on the energy required for communition of rock

The most energy-intensive process in the mining industry is particle size reduction - comminution. The first phase of this process is blasting to fragment the rock from the initial Boussinesq's half-space size. Scientific literature demonstrates that the output of a blast in terms of fragment size distribution can be manipulated by varying the specific charge (powder factor) and charge distribution. This study focuses on the influence of blasting on the internal resistance of the blasted fragments; in particular the influence of the spatial distribution of charges. Small-scale blasts were performed on 14 marble blocks using different powder factors and charge distributions. Three control blocks were fragmented by mechanical means for comparison. The results show the correlations between charge distributions and the specific energy of mechanical comminution. Opportunities for adjusting charge diameter and distribution in opencast blasts to improve the performancet of comminution circuits are discussed.

Aerodynamic breakup of emulsion droplets in airflow

AbstractAerodynamic breakup refers to the process where large droplets are fragmented into small droplets by the aerodynamic force in airflow, which plays a vital role in fluid atomization and spray applications. Previous research has primarily concentrated on the aerodynamic breakup of single‐component droplets, but investigations into the breakup of emulsion droplets are limited. This study experimentally investigated the aerodynamic breakup of water‐in‐oil emulsions in airflow, utilizing high‐speed photography to observe the breakup process and digital in‐line holography to measure fragment sizes. Comparative analyses between emulsion droplets and single‐component droplets are conducted to examine the breakup morphology, breakup regime, deformation characteristics, and fragment size distributions. The emulsion droplets exhibit higher apparent viscosity and shorter stretching lengths of the bag film and peripheral rim due to the presence of a dispersed phase. The breakup regime transitions of emulsions are modeled by integrating the viscosity model of emulsions and the transition model of the pure fluid. The fragment sizes of emulsion droplets are larger due to the shorter lengths of the bag film and peripheral rim.

Genomic profiling of cell-free DNA from dogs with benign and malignant tumors

ObjectiveCancer is currently the most common cause of death in adult dogs. Like humans, dogs have a one-third chance of developing cancer in their lifetime. We used shallow whole-genome sequencing (sWGS) to analyze blood cell-free DNA (cfDNA) from four tumor-bearing dogs (one with benign and three with malignant tumors) and 38 healthy dogs.ResultsSimilar to the results observed in the healthy dogs, no copy number aberration (CNA) was detected in the dog with benign lipomas, and the distribution of cfDNA fragment size (FS) closely resembled that of the healthy dogs. However, among the three dogs diagnosed with malignant tumors, two dogs exhibited varying degrees and quantities of CNAs. Compared to the distribution of FS in the healthy dogs, the cancer dogs exhibited a noticeable shift towards shorter lengths. These findings indicated that CNA and FS profiles derived from sWGS data can be used for non-invasive cancer detection in dogs.

Dynamic fracture mechanism and fragment characteristics of sandstone specimens with asymmetrical conjugate fissures under static pre-compression

This paper systematically investigates the dynamic mechanical response and fragment characteristics of sandstone with asymmetrical conjugate fissures subjected to preexisting static stress based on the split Hopkinson pressure bar apparatus. The cross-fissured sandstone exhibits significant variations in mechanical behavior when exposed to higher dynamic strain rates under identical static pre-stress. The cross-fissured sandstone with a higher dynamic strain rate is characterized by a greater coupled strength under the same static pre-stress; for a given dynamic load, the highest coupled strength occurs under the static pre-stress of 60% UCS. The failure mode of the cross-fissured sandstone is predominantly governed by the dynamic strain rate, independent of static pre-stress variations considered in this investigation. At lower dynamic strain rates, the specimens typically exhibit a mixed tensile-shear failure mode, characterized by the dominance of larger fragments in the broken specimens. In contrast, under high dynamic impacts, the sandstone tends to fail in a shear-dominated manner, resulting in smaller fragments with a more uniform size distribution. Furthermore, the study explores how varying dynamic strain rates and static pre-stress influence the fragment characteristics of the cross-fissured sandstone. Higher dynamic strain rates and increased static pre-stress generally lead to smaller mean fragment sizes. This phenomenon is quantitatively described by fitting fragment size distributions using the Generalized Extreme Value (GEV) distribution, revealing a decrease in the location parameter (μ) and an increase in fractal dimension. These metrics indicate that higher dynamic strain rates and static pre-stress result in sandstone specimens breaking into smaller fragments with a more homogeneous size distribution. These findings contribute to a deeper understanding of rock dynamics, with potential implications for engineering applications involving similar geological configuration under dynamic loading conditions.

Field evidence and indicators of rockfall fragmentation and implications for mobility

Rockfall fragmentation can play an important role in hazard studies and the design of protective measures. However, the current lack of modeling tools that incorporate rock fragmentation mechanics is a limitation to enhancing studies and design. This research investigates the fragmentation patterns of rockfalls and analyzes the resulting distribution of fragment sizes within corresponding rockfall deposits. We focus on small rock fragments, which provide insights into the dynamics of the rockfall event and can be used as input for numerical modeling. We analyzed multiple rockfall events from locations worldwide, each exhibiting different degrees of fragmentation. Using image analysis techniques, we mapped all visible blocks, determined their volumes, and measured the distances they travelled from the initial point of impact. A key finding is the identification of three indicators of fragmentation. First, in cases where fragmentation was largely absent, we observed a trend of increasing block size with distance from the impact point or source area, which aligns with previously published findings. However, for energetic rockfall events characterized by intense fragmentation, we observed that small fragments exhibited longer travel distances compared to larger fragments. This distinction allowed us to differentiate blocks primarily resulting from the disaggregation process from those primarily resulting from dynamic fragmentation, with implications for rockfall mobility. Second, although the size distribution of rockfall deposits exhibits a power-law scaling for volumes larger than a minimum size threshold corresponding to a rollover of the distribution, in some case studies a deviation from power-law scaling is observed, indicating a process of larger block comminution due to fragmentation. Third, we found that rockfalls with fragmentation experience reduced mobility, indicated by higher reach angles, and higher lateral dispersion showing a wider distribution of trajectories. We interpret these findings as being directly related to the energy-consuming nature of fragmentation, which prevents farther deposition of fragmented rock blocks.

Dynamic Response and Rock Damage of Different Shapes of Cavities under Blasting Loads

In order to investigate the dynamic response and rock mass damage characteristics of cavities with different shapes under blasting loads, this paper, through a combination of model tests and numerical simulations, studies the stress distribution, strain, failure modes, and blasting fragment size distribution of cavities with different shapes subjected to blasting loads. The results show that under the action of blasting loads, the presence of cavities with different shapes significantly affects the blasting effects and rock mass damage. Spherical cavities exhibit excellent blast resistance, whereas rectangular and triangular cavities are prone to stress concentration at their tips, which in turn promotes rock mass damage and failure. Subsequent analysis of the blasting fragment sizes reveals that rectangular and triangular cavities yield more favorable blasting results than spherical cavities. The research findings provide important theoretical foundations and practical guidance for the design and construction of underground engineering blasting, contributing to enhancing engineering safety and promoting the sustainable development of the underground engineering industry.

Time-dependent damage characteristics of shale induced by fluid–shale interaction: a lab-scale investigation

The shale’s multi-scale mechanical behaviors were investigated to understand the time-dependent damage characteristics induced by shale–fluid interaction. The test results indicate that, as fluid–shale interaction proceeds, the mechanical strength of shale has undergone a weakened to an enhanced process as interaction proceeds, and the size distribution of fragments tends to be more uniform, leading to a positive correlation between the mechanical strength and fractal dimension. Within 2 weeks of fluid–shale interaction show a decreasing trend for the fractal dimension of fragments in post-failure and cause less than 2 mm for the dominant size of fragments. The dominant size increases to greater than 30 mm when the fluid–shale interaction is over 2 weeks. Finally, the correlation dimension associated with ring counts of acoustic emission (AE) at each loading stage is determined in terms of the G-P algorithm to predict the damage degree of shale.

Study on fragmentation characteristics of carbon nanotube-enhanced concrete and a comparative evaluation of the ZWT and ottosen constitutive model

In order to study the difference between the crushing characteristics of carbon nanotubes (CNTs) concrete and ordinary concrete, this paper conducts a test between ordinary concrete and CNTs concrete with a volume content of 0.3 % at different impact speeds through the Hopkinson test, using fragmentation and particle size distribution as evaluation indexes. Crushed fragments are analyzed from the perspective of concrete pores. Finally, the nonlinear viscoelastic constitutive model and the nonlinear elastic constitutive model of CNTs concrete are then developed and compared. Based on the results, the average pores of the CNTs concrete decreased from 42.0 nm to 38.0 nm, but the pore area increased from 5.743 m2/g to 6.305 m2/g, indicating that CNTs can fill the internal pores. Meanwhile, the average particle size of broken CNTs concrete is significantly larger than that of ordinary concrete. However, the relationship between the crushing particle size and impact velocity is approximately y=A-Bln(x+C) for both concretes. According to the study of concrete constitutive models, compared to the Loand damage model, the combination of Loand model and Mazars model is more accurate in describing concrete damage characteristics, and the average correlation coefficient increases from 0.84 to 0.92. Meanwhile, compared to the Zhu-Wang-Tang (ZWT) model, Ottosen model can better capture the dynamic mechanical properties of CNT concrete, with a correlation coefficient over 0.98.

Quantifying mine waste rock physical weathering rate and processes for improved geomorphic post-mining landforms

Erodibility of landform surfaces depends on several factors and numerical methods are needed to predict erosion and landform evolution particularly for post-mining landscapes. Surface armouring caused by immobile coarse particles tends to reduce the erosion potential of landform surfaces significantly. However, the breakdown of such material through weathering could destabilise this armour and lead to high erosion rates. Hence, the surface erodibility of newly constructed landforms (here we focus on post-mining landforms) can rapidly change over a few years to decades. At present, it is difficult to predict with certainty the rate, or in some cases the dominant processes and pathways, of soil erodibility and soil production over post-mining landscape design lifetimes (typically 100–1000 years). To improve our understandings of soil evolution and its relationship to soil erosion, data is needed to determine the rate at which fine transportable material is produced from the weathering of larger, non-transportable particles, the resultant fragment size distribution together, and how that distribution evolves over time.Here, laboratory weathering experiments were conducted for four different materials from a single coal mine in the Bowen Basin, Queensland, Australia. Wetting and drying cycles were found to rapidly weather all materials. After 32 wet and dry cycles, all materials had a less coarse particle size distribution than at the start. Heating and cooling had no measurable influence on weathering. Due to the rapid reduction of particle sizes caused by high weathering rates, the materials examined would not provide surface armour capability. A new mathematical methodology was developed to determine the weathering parameters for an existing numerical model based on the weathering mechanism and particle size-dependent weathering rate. Although the materials were collected from the same geographical location, they undergo weathering through different mechanisms and rates. Size dependent weathering rate analysis showed that most samples have high weathering rates for large particles and lower weathering rates for smaller particles. The methods used here are simple and inexpensive and can be easily employed to assess mine rehabilitation materials' weathering and armour potential.

A novel intelligent stereo vision approach for blast-induced fragmentation size distribution: Case study at Golgohar open-pit mine, Iran

Rock fragmentation assessment is a critical aspect of evaluating blasting operations in the mining industry, offering insights for optimising procedures and subsequent mining processes. Traditional methods, such as sieving, while accurate, are costly and time-consuming. Digital image analysis methods have emerged as alternatives, yet they face challenges in accurately handling fragments of varying sizes. Recent advancements in computer vision, particularly deep learning techniques, offer promising solutions to automate and refine fragmentation analysis. This paper introduces a novel intelligent stereo vision approach utilising YOLOv8, an advanced deep learning model, for blast-induced fragmentation size distribution assessment at the Golgohar open-pit mine in Iran. By training YOLOv8 with an automated self-labelled dataset and evaluating its performance against real mine site data, this research aims to enhance the accuracy and efficiency of blast fragmentation analysis. The proposed method leverages stereo images and machine learning to provide precise measurements, leading to improved optimisation of blasting parameters and potential economic benefits compared to traditional methods. Through rigorous validation processes and case studies across diverse scenarios, the proposed approach demonstrates robustness and reliability in assessing blast fragmentation, offering a practical and efficient solution for the mining industry’s evolving needs.

Energy control and block performance optimization of bench blasting

In this study, rock-like model blast tests with varying toe burdens are conducted and the evolution of blast-induced fractures is analyzed using the digital image correlation (DIC) method. In addition, post-blast fragmentations are image-processed to quantitatively investigate the blasting performance. A three-dimensional numerical model is developed and validated against the experimental results. The effects of blasthole inclination (70°, 80°, and 90°) and short delays on fragment size distribution (FSD) are numerically investigated. Field trials are conducted to verify the numerical results. The experimental results reveal that the overall fragment size increases significantly in proportion to the toe burden. The explosion energy utilization rates range from 3.56 % to 13.16 %, with a tendency to initially increase and subsequently decrease. The numerical results demonstrate that fragments are more evenly distributed with a blasthole inclination of 70°, resulting in a remarkable improvement in rock fragmentation compared to a vertical blasthole. Compared to the toe burden, the influence of short delays on concrete fragmentation is insignificant. The field test results indicate that a narrower FSD range and stable pit walls are achieved by utilizing inclined blastholes in bench blasting. This study provides theoretical guidance for optimizing bench blasting parameters, which has practical significance for improving explosive energy utilization and production efficiency in open-pit mines.

Laminated insulated glass units under blast loads: Experimental and numerical study

Laminated insulating glass units (IGUs), commonly used in modern buildings, are prone to shattering from explosive loads, causing significant damage and loss. Existing research on IGUs is constrained by a lack of experimental validation and comprehensive numerical analyses, as large-scale explosion tests are rarely reported due to safety and cost concerns. Furthermore, previous modeling efforts often oversimplify critical factors such as the supporting structure, component interactions, strain rate effects, hourglass energy, and failure criteria, leading to an inadequate representation of glass behavior under explosive loads. This paper addresses these gaps by conducting large-scale explosive test on glass system and utilizing sophisticated nonlinear dynamic analysis with LS-DYNA for simulation. The research considers the influence of the support system and incorporates detailed considerations of component interactions, constitutive relationships, and strain rate effects in the numerical simulations. The results confirm that the proposed model successfully replicates the crack patterns and damage observed in experimental test. Also, it accurately predicts the trajectory, quantity, and size distribution of glass fragments. The proposed modeling approach offers a more informed assessment of damage and improves the evaluation of glass safety in practical applications.

APEAch: Automated Pipeline for End-to-End Analysis of Epigenomic and Transcriptomic Data.

With the advent of next-generation sequencing (NGS), experimental techniques that capture the biological significance of DNA loci or RNA molecules have emerged as fundamental tools for studying the epigenome and transcriptional regulation on a genome-wide scale. The volume of the generated data and the underlying complexity regarding their analysis highlight the need for robust and easy-to-use computational analytic methods that can streamline the process and provide valuable biological insights. Our solution, aPEAch, is an automated pipeline that facilitates the end-to-end analysis of both DNA- and RNA-sequencing assays, including small RNA sequencing, from assessing the quality of the input sample files to answering meaningful biological questions by exploiting the rich information embedded in biological data. Our method is implemented in Python, based on a modular approach that enables users to choose the path and extent of the analysis and the representations of the results. The pipeline can process samples with single or multiple replicates in batches, allowing the ease of use and reproducibility of the analysis across all samples. aPEAch provides a variety of sample metrics such as quality control reports, fragment size distribution plots, and all intermediate output files, enabling the pipeline to be re-executed with different parameters or algorithms, along with the publication-ready visualization of the results. Furthermore, aPEAch seamlessly incorporates advanced unsupervised learning analyses by automating clustering optimization and visualization, thus providing invaluable insight into the underlying biological mechanisms.

Strain rate effects on fragment morphology of ceramic alumina: A synchrotron-based study

Dynamic (600–1000 s−1) and quasi-static (0.001–0.01 s−1) compression experiments are conducted on a high-purity alumina ceramic using a split Hopkinson pressure bar and a material test system, respectively. The postmortem fragments of ceramic samples at different strain rates are then characterized via synchrotron micro computed tomography (CT). The three-dimensional (3D) morphologies of fragments are quantified using the gyration tensor analysis after proper segmentation of CT images. The mean fragment size decreases in a power-law form while the mean shape indices (sphericity, elongation index and flatness index) increase in a logarithmic-linear form, with increasing strain rates. In addition, the fragment size and shape distributions are all found to follow the Weibull probability distribution. To reveal the underlying mechanisms of such strain rate effects, high-speed optical and X-ray imaging are implemented to capture the fracture process of ceramic samples under quasi-static and dynamic compression. Primary and secondary wing cracks (PWCs/SWCs) control the fracture and fragmentation of the ceramic under both loading conditions. Compared to quasi-static loading, a considerably larger number of SWCs are produced under dynamic loading, and pronounced branching and bridging occur among the PWCs, which prevent the PWCs from coalescing into axial splitting cracks. Consequently, crack networks composed of high-density wing cracks break the sample into finer and more isotropic fragments, consistent with CT characterizations. Scanning electron microscopy is utilized to analyze the micro damage modes of ceramic samples. Transgranular fracture dominates the grain-scale damage and contributes to the higher dynamic fracture resistance of the alumina under dynamic loading, as a result of more homogeneous nucleation and growth of micro cracks.