Original Size Research Articles

A visually secure image encryption scheme based on adaptive block compressed sensing and non-negative matrix factorization

The traditional block compressive sensing theory cannot make full use of the difference of image block information characteristics for sampling, and the measurement matrix cannot fully measure the image according to the image block information characteristics. To solve these problems, we design an adaptive block compressed sensing (ABCS) algorithm, and we propose a visually secure image encryption scheme based on ABCS and non-negative matrix factorization (NMF). First, the plain image is decomposed by Tetrolet transform. Then, we perform matrix shuffling to optimize the sparsity of the sparse matrix. Next, adaptive sampling and measurement are performed according to the information distribution characteristics between the image blocks to compress the image to a quarter of its original size. Last, we design a scrambling–diffusion framework based on tetrominoes to obtain the secret image, which is then embedded into the carrier image by means of NMF to obtain a visually secure cipher image. The experimental results show that the proposed scheme can consider the security of image information transmission and the integrity of reception, and has good resistance to various attacks.

PRIMARY CULTURE AND IDENTIFICATION OF MOUSE BRAIN MICROVASCULAR ENDOTHELIAL CELLS

Brain microvascular endothelial cells are the basic components of the blood-brain barrier. Many neurological diseases are related to the loss of blood brain barrier (BBB) function. Isolating and culturing primary BMVEC is an important means to study the function and regulation of BBB in vitro. To establish a method for isolation and culture of primary mouse brain microvascular endothelial cells (BMECs). The 7-10-days mice were sacrificed by neck removal, the cranial cavity was opened, the brain was aseptically removed and the cerebral cortex was retained. To extract brain microvascular segments, the brain underwent three D-Hank solution rinses. It was then homogenized, twice digested by enzyme, and centrifuged using a Bovine Serum Albumin (BSA) gradient. For primary culture, the brain microvascular segments were injected into gelatin-coated culture plates using DMED complete media. When the cell density reaches 90 %, the media is removed, and the cells are then given two PBS washes. A new medium was introduced after adding 1ml of the trypsin-EDTA solution to digest for 2–5 minutes for passage. Cell culture plates were rinsed and pre-cooled 95 % ethanol was added for 20 minutes after passaged cells had grown to 80–90 % of their original size. After a third wash, 1 ml of mouse factor VIII antibody was added to the culture wells, where it was left for 4 hours at 37 °C. FITC-labeled rabbit anti-mouse antibody in a volume of 1 mL was added. Under a confocal laser microscope, the plates were examined and taken pictures of. The outcome demonstrates positive expression of the marker factor VIII associated antigen. To create a cell suspension, monolayer-growing microvascular endothelial cells were chosen. 100 L of cell suspension was used to inoculate each well in 96-well plates, and the cells were then grown. On days 1, 2, 3, 4, 5, 6, and 7, the original medium was removed, and then 180 μL of DMEM and 20 μL of MTT were simultaneously added to each well for a 4-hour culture. After adding dimethyl sulfoxide (DMSO), each well's absorbance value (A value) was measured at 492 nm. The outcome demonstrates that the growth peak is attained between 6 and 8 days. This method can successfully isolate and culture primary BMECs, which lay a foundation for the study of BMEC in vitro.

Sintering-free catalytic ammonia cracking by vertically standing 2D porous framework supported Ru nanocatalysts

Catalytic ammonia decomposition enables ammonia to be a hydrogen gas carrier for a carbon-free fuel economy. The challenge is to obtain high conversion yields and rates at low temperatures for a prolonged time. A promising approach is to engineer a catalyst support to minimize deleterious effects like sintering. Here, we compared a conventional 2D planar porous framework support with a vertically standing 2D structure to ascertain the effects of support geometry on the catalytic performance. The catalysts were made by loading ruthenium (Ru) nanoparticles onto the structures, and the catalytic activities were monitored by varying the ammonia (NH3) feeding rate and reaction temperature. Unlike the planar version, the vertically standing 2D support prevented nanoparticle aggregation, retained the original nanoparticle size, and showed an excellent hydrogen production rate (95.17 mmol gRu−1 min−1) at a high flow rate of 32,000 mL gcat−1 h−1 at a temperature of 450 °C.

Ultrasound-guided breast biopsy using an adapted automated cone-based ultrasound scanner: a feasibility study.

Among available breast biopsy techniques, ultrasound (US)-guided biopsy is preferable because it is relatively inexpensive and provides live imaging feedback. The availability of magnetic resonance imaging (MRI)-3D US image fusion would facilitate US-guided biopsy even for US occult lesions to reduce the need for expensive and time-consuming MRI-guided biopsy. In this paper, we propose a novel Automated Cone-based Breast Ultrasound Scanning and Biopsy System (ACBUS-BS) to scan and biopsy breasts of women in prone position. It is based on a previously developed system, called ACBUS, that facilitates MRI-3D US image fusion imaging of the breast employing a conical container filled with a coupling medium. The purpose of this study was to introduce the ABCUS-BS system and demonstrate its feasibility for biopsy of US occult lesions. The biopsy procedure with the ACBUS-BS comprises four steps: target localization, positioning, preparation, and biopsy. The biopsy outcome can be impacted by 5 types of errors: due to lesion segmentation, MRI-3D US registration, navigation, lesion tracking during repositioning, and US inaccuracy (due to sound speed difference between the sample and the one used for image reconstruction). For the quantification, we use a soft custom-made polyvinyl alcohol phantom (PVA) containing 8 lesions (3 US-occult and 5 US-visible lesions of 10 mm in diameter) and a commercial breast mimicking phantom with a median stiffness of 7.6 kPa and 28 kPa, respectively. Errors of all types were quantified using the custom-made phantom. The error due to lesion tracking was also quantified with the commercial phantom. Finally, the technology was validated by biopsying the custom-made phantom and comparing the size of the biopsied material to the original lesion size. The average size of the 10-mm-sized lesions in the biopsy specimen was 7.00 ± 0.92 mm (6.33 ± 1.16 mm for US occult lesions, and 7.40 ± 0.55 mm for US-visible lesions). For the PVA phantom, the errors due to registration, navigation, lesion tracking during repositioning, and US inaccuracy were 1.33 mm, 0.30 mm, 2.12 mm, and 0.55 mm. The total error was 4.01 mm. For the commercial phantom, the error due to lesion tracking was estimated at 1.10 mm, and the total error was 4.11 mm. Given these results, the system is expected to successfully biopsy lesions larger than 8.22 mm in diameter. Patient studies will have to be carried out to confirm this in vivo. The ACBUS-BS facilitates US-guided biopsy of lesions detected in pre-MRI and therefore might offer a low-cost alternative to MRI-guided biopsy. We demonstrated the feasibility of the approach by successfully taking biopsies of 5 US-visible and 3 US-occult lesions embedded in a soft breast-shaped phantom. This article is protected by copyright. All rights reserved.

Combining National Surveys with Composite Calibration to Improve the Precision of Estimates from the United Kingdom's Living Costs and Food Survey

Abstract The United Kingdom’s Living Costs and Food (LCF) Survey has a relatively small sample size but produces estimates which are widely used, notably as a key input to the calculation of weights for consumer price indices. There has been a recent call for the use of additional data sources to improve the estimates from the LCF. Since some LCF variables are shared with the much larger Labour Force Survey (LFS), we investigate combining data from these surveys using composite calibration to improve the precision of estimates from the LCF. We undertake model selection to choose a suitable set of common variables for the composite calibration using the effect on the estimated variances for national and regional totals of important LCF variables. The variances of estimates for common variables are reduced to around 5 percent of their original size. Variances of national estimates are reduced (across several quarters) by around 10 percent for expenditure and 25 percent for income; these are the variables of primary interest in the LCF. Reductions in the variances of regional estimates vary more but are mostly large when using common variables at the regional level in the composite calibration. The composite calibration also makes the LCF estimates for employment status almost consistent with the outputs of the LFS, which is an important property for users of the statistics. A novel alternative method for variance estimation, using stored information produced by the composite calibration, is also presented.

Mathematical Description of the Functioning of the Pulsatory Liposome

We consider a liposome filled with the aqueous solution of an osmotic solute enclosed in a large water bath. Due to osmotic pressure, it works according to a sequence of cycles with two stages. In the first stage, the lipid vesicle with a certain input concentration of the osmotic substance is swelling up in an osmotic process until it reaches a size, when one pore is formed on its surface. The second stage follows, where the vesicle content is partially eliminated through the pore to induce a decrease in the vesicle volume up to its original size. If we take into account that the pore has two stages in its evolution, then the relaxing stage may be divided into two new stages. The swelling of the liposome is described by a differential equation. All the processes which contribute to the vesicle relaxing and its return to the initial size are described by three differential equations.

Analysis of success rate of organoid construction of nasopharyngeal carcinoma by first-day suspension method

Objective: To investigate the efficacy of the first-day suspension method for improving the success rate of construction of nasopharyngeal carcinoma-patient derived organoids (NPC-PDO). Methods: The tumor samples of 14 nasopharyngeal carcinoma(NPC) patients, i.e.,13 males and 1 female, with a mean age of 43.0±12.0 years old, were collected from the Affiliated Tumor Hospital of Guangxi Medical University and the First Affiliated Hospital of Guangxi Medical University from January 2022 to July 2022. The tumor samples of 3 patients were digested into single cell suspension and divided into 2 groups, for comparing the efficacy of NPC-PDO construction by the direct inoculation method and the first-day suspension method. The remaining 11 patients were randomized to receive either the direct inoculation method or the first-day suspension method for NPC-PDO construction. The diameter and the number of spheres of NPC-PDO constructed by the two methods were compared by optical microscope; the 3D cell viability detection kit was used to compare the cell viability; the survival rates were compared by trypan blue staining; the success rates of the two construction methods were compared; the number of cases which could be successfully passaged for more than 5 generations and were consistent with the original tissue by pathological examination was counted; and the dynamic changes of cells in suspension overnight were observed by live cell workstation. The independent sample t-test was applied to compare the measurement data of the two groups, and the chi-square test was used to compare the classification data. Results: Compared with the direct inoculation, the diameter and the number of spheres of NPC-PDO constructed by the first-day suspension method were increased, with a higher cell activity, and the success rate of construction was obviously improved (80.0% vs 16.7%, χ2=4.41, P<0.05). In the suspension state, some of the cells aggregated and increased their ability to proliferate. Conclusion: The first-day suspension method can improve the success rate of NPC-PDO construction, especially for those whose original tumor sample size is small.

A Novel Image Encryption Technique with Four Stage Bit-Interspersing and A 4D-Hyperchaotic System

This paper introduces a new technique of color image encryption that includes four stages of bit interspersing and a 4D-hyperchaotic system. At first, the pixel values for different RGB channels of a plane color image were represented by an 8-bit binary number. The bit interspersing operation has been implemented on the bit stream generated by considering a particular block size for each color channel and reshaping it to the original size. The cipher image was then constructed by performing a bit XOR operation on the resultant image and the chaotic sequences generated by a 4D hyperchaotic system. The initial state variables of the said chaotic system have been developed from a 32-character secret key. This operation has been repeated three times, considering different block sizes of the newly generated cipher image after each stage. The main strengths of the proposed algorithm are the bit interspersing and image-dependent chaotic key base pixel substitution by bitwise XOR operation. A set of standard security tests are conducted to test the reliability of the suggested encryption method. Comparing the crypto-parameters to other recent works, we find that the proposed algorithm is better than the other methods.

Incremental and interactive relations of triarchic psychopathy measure scales with antisocial and prosocial correlates: A preregistered replication of Gatner et al. (2016).

Meanness (i.e., callousness/unemotionality, antagonism) and disinhibition (e.g., impulsivity, antisocial behavior) are the consensus traits that undergird psychopathy. Significant debate exists regarding a proposed third dimension of boldness or fearless dominance, characterized by particularly high levels of both extraversion and emotional stability. The present study is a preregistered direct replication of the work of Gatner and colleagues (2016) regarding the importance of boldness in psychopathy. Specifically, in a large undergraduate sample (n = 1,015), which more than doubled the original study sample size, we examined whether boldness exhibited curvilinear relations to antisocial and prosocial outcomes, provided incremental predictive utility, and interacted with meanness and disinhibition. Consistent with Gatner and colleagues' findings, incremental, interactive, or curvilinear effects of boldness did not account for more than a small amount of variance in outcomes beyond the main effects of meanness and disinhibition. We discuss both process and results in the context of promoting a culture of reproducibility as well as transparent and open practices in clinical science. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Microstructure characteristics at different depths of 40CrNiMo steel after laser hardening

This study focuses on laser-hardened 40CrNiMo steel, which meets the requirements for use in sprag clutch wedges; specifically, the microhardness characteristics as well as the phase and element characteristics and formation mechanism at different depths are investigated after laser hardening. The results show that the hardness of the arc-shaped specimen with a laser-hardened layer fluctuates significantly after reaching a certain depth. With increasing depth, the original austenite grain size decreases exponentially, it becomes easier for acicular martensite to form near the surface, and the martensite bulge phenomenon near the surface is more pronounced. The proportion of small-angle grain boundaries decreases, while that of large-angle grain boundaries increases after laser hardening. The angle of the small-angle grain boundaries of the adjacent grains of the hardened layer is mostly below 5°, while that of the large-angle grain boundaries is predominantly between 50° and 60°. After laser hardening, the preferred orientation of the grains in the hardened layer is not clear. The aggregation of C atoms is an important factor determining the structural characteristics of the hardened layer.

A Unified Model for Bipolar Outflows from Young Stars: Apparent Magnetic Jet Acceleration

We explore a new, efficient mechanism that can power toroidally magnetized jets up to two to three times their original terminal velocity after they enter a self-similar phase of magnetic acceleration. Underneath the elongated outflow lobe formed by a magnetized bubble, a wide-angle free wind, through the interplay with its ambient toroid, is compressed and accelerated around its axial jet. The extremely magnetic bubble can inflate over its original size, depending on the initial Alfvén Mach number M A of the launched flow. The shape-independent slope ∂v r /∂r = 2/3t is a salient feature of the self-similarity in the acceleration phase. Peculiar kinematic signatures are observable in the PV diagrams and can combine with other morphological signatures as probes for density-collimated jets arising in toroidally dominated magnetized winds. The apparent second acceleration is powered by the decrease of the toroidal magnetic field but operates far beyond the scales of the primary magnetocentrifugal launch region and the free asymptotic terminal state. Rich implications may connect the jets arising from the youngest protostellar outflows such as HH 211 and HH 212 and similar systems with parsec-scale jets across the mass and evolutionary spectra.

HEVC extension for phase hologram compression.

Compressing digital holograms have growing attention nowadays due to their huge amount of original data sizes. Although many progresses have been reported for full-complex holograms, the coding performance for phase-only holograms (POHs) has been quite limited so far. In this paper, we present a very efficient compression method for POHs. It extends the conventional video coding standard HEVC (High Efficiency Video Coding) in such a way that the standard can be able to compress not only the natural images but also the phase images effectively. First, we suggest a proper way to calculate differences, distances and clipped values for phase signals by considering the inherent periodicity of phases. Then, some of the HEVC encoding and decoding processes are modified accordingly. The experimental results show that the proposed extension significantly outperforms the original HEVC for POH video sequences; specifically, average BD-rate reductions of 63.3% and 65.5% are achieved in phase domain and numerical reconstruction domain, respectively. It is worth mentioning that the modified encoding & decoding processes are very minimal and also applicable to the VVC (Versatile Video Coding), which is a successor of the HEVC.

Long-term neurodevelopmental follow-up of children exposed to pravastatin in utero

Preeclampsia, especially before term, increases the risk of child neurodevelopmental adverse outcomes. Biological plausibility, preclinical studies, and pilot clinical trials conducted by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the Obstetric-Fetal Pharmacology Research Centers Network support the safety and use of pravastatin to prevent preeclampsia. This study aimed to determine the effect of antenatal pravastatin treatment in high-risk pregnant individuals on their child's health, growth, and neurodevelopment. This was an ancillary follow-up cohort study of children born to mothers who participated in the Obstetric-Fetal Pharmacology Research Centers Network pilot trials of pravastatin vs placebo in individuals at high risk of preeclampsia (ClinicalTrials.gov; identifier NCT01717586). After obtaining written informed consent (and assent as appropriate), the parent was instructed to complete the Child Behavior Checklist. To assess the child's motor, cognitive, and developmental outcomes, a certified and blinded study psychologist completed child motor, cognitive, emotional, and behavioral assessments using validated tools. Given the small number of individuals in the studies, the 10- and 20-mg pravastatin groups were combined into 1 group, and the results of the pravastatin group were compared with that of the placebo group. Of 40 children born to mothers in the original trial, 30 (15 exposed in utero to pravastatin and 15 to placebo) were enrolled in this follow-up study. The time of follow-up, which was 4.7 years (interquartile range, 2.5-6.9), was not different between children in the pravastatin group and children in the placebo group. There was no difference in the child's body mass index percentiles per sex and corrected age, the rates of extremes of body mass index percentiles, or the report of any other medical or developmental complications between the 2 groups. No child born in the pravastatin group had any limitation in motor assessment compared with 2 children (13.3%) who walked with difficulty and 4 children (26.7%) who had reduced manual abilities in the placebo group. Moreover, children born to mothers who received pravastatin had a higher general mean conceptual ability score (98.2±16.7 vs 89.7±11.0; P=.13) and a lower frequency (15.4% vs 35.7%; P=.38) of having a score of <85 (ie, 1 standard deviation lower than the mean) compared with those in the placebo group. Finally, there was no difference in the parents' report on the Child Behavior Checklist between the 2 groups. This study reported on the long-term neuromotor, cognitive, and behavioral outcomes among children exposed to pravastatin in utero during the second and third trimesters of pregnancy. Although the data were limited by the original trial's sample size, no identifiable long-term neurodevelopmental safety signal was evident with the use of pravastatin during pregnancy. This favorable neonatal risk-benefit analysis justifies continued research using pravastatin in clinical trials.

Molecularly Imprinted Polymers with Shape-Memorable Imprint Cavities for Efficient Separation of Hemoglobin from Blood.

Efficient separation and purification of hemoglobin from blood and other complicated biological fluids still remains a big challenge. Molecularly imprinted polymers (MIPs) of hemoglobin are potential choices; however, they suffer from severe problems including difficult template removal and low imprinting efficiency like other protein-imprinted polymers. Herein, a novel MIP of bovine hemoglobin (BHb) was designed in which a peptide crosslinker (PC), instead of the commonly used crosslinkers, was used. The PC, a random copolymer of lysine and alanine, adopts an α-helical conformation at pH 10 but transits to a random coil conformation at pH 5. The introduction of alanine residues lowers the pH range at which the PC undergoes helix-coil transition. The imprint cavities in the polymers are shape-memorable due to the reversible and precise helix-coil transition of the peptide segments in the polymers. They can be enlarged by lowering pH from 10 to 5, thus allowing complete removal of the template protein under mild conditions. When the pH is adjusted back to 10, their original size and shape will be recovered. Therefore, the MIP binds the template protein BHb with high affinity. Compared with the MIP crosslinked with the commonly used crosslinker, the imprinting efficiency of the PC-crosslinked MIP is significantly improved. In addition, both the maximum adsorption capacity (641.9 mg/g) and imprinting factor (7.2) are much higher than the BHb MIPs reported previously. The new BHb MIP also exhibits high selectivity toward BHb and good reusability. Thanks to the high adsorption capacity and high selectivity of the MIP, when it was applied to extract BHb from bovine blood, BHb in the blood sample was extracted almost completely, and high purity product was obtained.

Unbound stars hold the key to young star cluster history

Aims.Gaia delivers the positions and velocities of stars at an unprecedented precision. Therefore, for star clusters, there exists much higher confidence in whether a specific star is a member of a particular cluster or not. However, membership determination is still especially challenging for young star clusters. At ages 2−10 Myr, the gas is expelled, ending the star formation process and leading to their expansion, while at the same time, many former members become unbound. As a first step, we aim to assess the accuracy of the methods commonly used to distinguish between bound and unbound cluster members; after identifying the most suitable technique for this task, we wish to understand which of the two populations is more suited to provide insights into the initial configuration and the dynamical history of a cluster starting from its currently observed properties. Methods. Here, we perform N-body simulations of the dynamics of such young star clusters. We investigate how cluster dynamics and observational limitations affect the recovered information about the cluster from a theoretical perspective. Results. We find that the much-used method of distance and velocity cutoffs for membership determination often leads to false negatives and positives alike. Often observational studies focus on the stars remaining bound. However, bound stars quickly lose the memory of the pre-gas expulsion phase due to their ongoing interaction with their fellow cluster members. Our study shows that it is the unbound stars that hold the key to charting a cluster’s dynamic history. Backtracking unbound stars can provide the original cluster size and determine the time of gas expulsion – two parameters that are currently still poorly constrained. This information is lost in the bound population. In addition, former members are often better indicators for disc lifetimes or initial binary fractions. We apply the backtracking analysis, with varying success, to the clusters: Upper Scorpius and NGC 6530. For highly substructured clusters such as Upper Scorpius, backtracking to the individual subcluster centres will provide better results in future.

Coal rheology – the effect of coal origin, rank, and particle size

ABSTRACT Coal rheology is a critical parameter for determining the coking and caking ability of metallurgical coals for cokemaking. The effect of rank, hardness differences due to rank, and particle size on the resultant fluidity and dilatation results were demonstrated for various rank Applachian coals in previous studies. Particles less than USA Standard screen size No. 140 had poorer rheology responses compared to other size fractions. For the third phase of this study, the effect of particle size and rank of Western Canadian coals were also evaluated. All samples and rheology parameters were determined prepared using the standard ASTM methods. In addition, rheology was also measured on sized subsets to determine the effect of particle size and rank on the overall rheology results but from a different geological era compared to Applachian coals. Particle size limits for the Gieseler and Dilatometer tests are suggested. The importance of using temperature range is also emphasized.

Multiscale feature fusion method for lane line detection based on time series

In order to solve lane line detection in difficult traffic conditions, such as shadow occlusion, signpost degradation, curves, and tunnels, numerous models have been proposed. However, most of the existing models conduct independent single-frame image detection, which makes it difficult to utilize the continuity of driving images and is ineffective in challenging scenes. To this end, we suggest a spatiotemporal information processing model for lane line recognition that enhances critical features. In order to properly learn the correlation between continuous images, we first employ a convolutional gated recurrent unit to process spatiotemporal driving information on the basis of U-Net. Second, the pyramid split attention (PSA) module is used to enhance or suppress the obtained feature expressions. Finally, the skip connection is used to fuse the features of different scales encoded by each stage with the features processed by PSA and gradually restore to the original image size. Experiments on the TuSimple dataset demonstrate that our model outperforms representative lane line detection networks in challenging driving scenes, with an F1-measure of up to 94.302%.

Experimental Study of Frost Crystals Dendrite Growth on Two Neighboring Separate Frozen Water Drops on a Cryogenic Cold Surface under Natural Convection Conditions

The effects of cold surface temperature, wet air state (temperature and humidity) and original drop size on frost dendrites growth of two neighboring separate frozen water drops of same size under natural convection conditions were investigated by quantitative measurement. It was determined that for different cold plate surface temperature conditions, i.e., the ordinary-low temperature and the cryogenic temperature range, the frost formation mechanism is different. Under the conditions that the air temperature is not too high and absolute humidity is not too excessive, the influence of frozen water drop size on the longest dendrite of frost crystals becomes more and more obvious with the decrease in cold plate temperature. The changes in air temperature and relative humidity both change air absolute humidity, so they have similar effects on the growth of dendrites. However, the effect of wet air state on the growth of frost dendrites is not monotonous, which needs to be considered comprehensively in combination with heat and mass transfer and the existence of heavy phase layer. The thickness of ‘the initial continuous frost layer’ was measured and it was disclosed that the initial frost layer thickness is 1.7–3.0 times that of the height of the frozen water drop diameter. This value may be possibly used as initial frost layer thickness in heat and mass transfer-based frost layer growth prediction models, at least for ordinary-low temperature conditions.

Aerial transport of bacteria by dust plumes in the Eastern Mediterranean revealed by complementary rRNA/rRNA-gene sequencing

Processes influencing the transport of airborne bacterial communities in the atmosphere are poorly understood. Here, we report comprehensive and quantitative evidence of the key factors influencing the transport of airborne bacterial communities by dust plumes in the Eastern Mediterranean. We extracted DNA and RNA from size-resolved aerosols sampled from air masses of different origins, followed by qPCR and high-throughput amplicon sequencing of 16 S ribosomal RNA gene and transcripts. We find that airborne bacterial community composition varied with air mass origin and particle size. Bacterial abundance, alpha diversity and species richness were higher in terrestrially influenced air masses than in marine-influenced air masses and higher in the coarse particle fraction (3.0 to 10.0 µm) than in the fine fraction (0.49 to 1.5 µm). This suggests that airborne bacteria mainly were associated with dust particles or transported as cell aggregates. High abundances of rRNA from human, animal and plant pathogen taxa indicate potential ecological impacts of atmospheric bacterial transport.

Research on power quality disturbance classification algorithm based on edge computing

Power quality analysis and governance need the identification of power quality issues. With the use of smart meters and various smart collection devices, more and more power quality data are collected, and the massive data collection brings pressure on communication, storage and computation to the conventional algorithm for identifying and classifying power quality disturbances based on cloud computing. In the paper, a classification algorithm for power quality disturbance identification based on edge computing and fusion model is proposed. The algorithm’s key concept is to compress and sense the power quality signals at the edge side, and then transmit the compressed power quality data to the cloud, which uses an improved Dense-Net and LSTM fusion model to identify and classify the compressed power quality data. Through experiments, it is proved that the method can compress the power quality signal to 70% of the original signal size while satisfying the recognition and data on power quality disturbance categorization accuracy, reducing the communication cost of data transmission, lowering the computational pressure and caching pressure on the cloud, and having certain robustness.