Vibration Signal Noise-Reduction Method of Slewing Bearings Based on the Hybrid Reinforcement Chameleon Swarm Algorithm, Variate Mode Decomposition, and Wavelet Threshold (HRCSA-VMD-WT) Integrated Model.

To enhance fault detection in slewing bearing vibration signals, an advanced noise-reduction model, HRCSA-VMD-WT, is designed for effective signal noise elimination. This model innovates by refining the Chameleon Swarm Algorithm (CSA) into a more potent Hybrid Reinforcement CSA (HRCSA), incorporating strategies from Chaotic Reverse Learning (CRL), the Whale Optimization Algorithm's (WOA) bubble-net hunting, and the greedy strategy with the Cauchy mutation to diversify the initial population, accelerate convergence, and prevent local optimum entrapment. Furthermore, by optimizing Variate Mode Decomposition (VMD) input parameters with HRCSA, Intrinsic Mode Function (IMF) components are extracted and categorized into noisy and pure signals using cosine similarity. Subsequently, the Wavelet Threshold (WT) denoising targets the noisy IMFs before reconstructing the vibration signal from purified IMFs, achieving significant noise reduction. Comparative experiments demonstrate HRCSA's superiority over Particle Swarm Optimization (PSO), WOA, and Gray Wolf Optimization (GWO) regarding convergence speed and precision. Notably, HRCSA-VMD-WT increases the Signal-to-Noise Ratio (SNR) by a minimum of 74.9% and reduces the Root Mean Square Error (RMSE) by at least 41.2% when compared to both CSA-VMD-WT and Empirical Mode Decomposition with Wavelet Transform (EMD-WT). This study improves fault detection accuracy and efficiency in vibration signals and offers a dependable and effective diagnostic solution for slewing bearing maintenance.

A Redactable Blockchain-Based Data Management Scheme for Agricultural Product Traceability.

With the development of agricultural information technology, the Internet of Things and blockchain have become important in the traceability of agricultural products. Sensors collect real-time data in agricultural production and a blockchain provides a secure and transparent storage medium for these data, which improves the transparency and credibility of agricultural product traceability. However, existing agricultural product traceability solutions are limited by the immutability of the blockchain, making it difficult to delete erroneous data and modify the scope of data sharing. This damages the credibility of traceability data and is not conducive to the exchange and sharing of information among enterprises. In this article, we propose an agricultural product traceability data management scheme based on a redactable blockchain. This scheme allows agricultural enterprises to encrypt data to protect privacy. In order to facilitate the maintenance and sharing of data, we introduce a chameleon hash function to provide data modification capabilities. Enterprises can fix erroneous data and update the access permissions of the data. To improve the efficiency of block editing, our scheme adopts a distributed block editing method. This method supports threshold editing operations, avoiding single-point-of-failure issues. We save records of data modifications on the blockchain and establish accountability mechanisms to identify malicious entities. Finally, in this paper we provide a security analysis of our proposed solution and verify its effectiveness through experiments. Compared with the existing scheme, the block generating speed is improved by 42% and the block editing speed is improved by 29.3% at 125 nodes.

Lipid bilayer membrane permeability mechanism of the K-Ras(G12D)-inhibitory bicyclic peptide KS-58 elucidated by molecular dynamics simulations.

Peptides are mid-size molecules (700-2000 g/mol) and have attracted particular interest as therapeutic modalities as they are superior in controlling protein-protein interactions, a process that is a typical drug target category, compared with small molecules (<500 g/mol). In 2020, we identified KS-58 (1333 g/mol) as a K-Ras(G12D)-inhibitory bicyclic peptide and suggested its cell membrane permeability. However, the membrane permeability mechanism had not been elucidated. In this study, we aim to clarify the mechanism by molecular dynamics (MD) simulations. Initially, we simulated the molecular conformations of KS-58 in water (a polar solvent) and in chloroform (a non-polar solvent). The identified stable conformations were significantly different in each solvent. KS-58 behaves as a chameleon-like molecule as it alters its polar surface area (PSA) depending on the solvent environment. It was also discovered that orientation of Asp's side chain is a critical energy barrier for KS-58 altering its conformation from hydrophilic to lipophilic. Taking these properties into consideration, we simulated its lipid bilayer membrane permeability. KS-58 shifted toward the inside of the lipid bilayer membrane with altering its conformations to lipophilic. When the simulation condition was set in deionized form of that carboxy group of Asp, KS-58 traveled deeper inside the cell membrane. PSA and the depth of the membrane penetration correlated. In vitro data suggested that cell membrane permeability of KS-58 is improved in weakly acidic conditions leading to partial deionization of the carboxy group. Our data provide an example of the molecular properties of mid-size peptides with membrane accessibility and propose an effective metadynamics approach to elucidate such molecular mechanisms by MD simulations.

Trapdoor proof of work.

Consensus algorithms play a crucial role in facilitating decision-making among a group of entities. In certain scenarios, some entities may attempt to hinder the consensus process, necessitating the use of Byzantine fault-tolerant consensus algorithms. Conversely, in scenarios where entities trust each other, more efficient crash fault-tolerant consensus algorithms can be employed. This study proposes an efficient consensus algorithm for an intermediate scenario that is both frequent and underexplored, involving a combination of non-trusting entities and a trusted entity. In particular, this study introduces a novel mining algorithm, based on chameleon hash functions, for the Nakamoto consensus. The resulting algorithm enables the trusted entity to generate tens of thousands blocks per second even on devices with low energy consumption, like personal laptops. This algorithm holds promise for use in centralized systems that require temporary decentralization, such as the creation of central bank digital currencies where service availability is of utmost importance.

Morphological evidence for the physiological nature of follicular atresia in veiled chameleons (Chamaeleo calyptratus).

Follicular atresia (FA) has been assumed to serve different functions in reptiles, e.g. helping to develop hierarchies, limiting clutch size, and regression of ovarian structures. Reproductive output is dependent on a balance between ovulations and FA. Excessive rates of FA may not only be detrimental for the survival of a population, but have also been associated with pathological conditions. In order to gain insights into the physiological and potentially pathological processes of FA, we performed a decriptive study on the morphological features of the ovaries in sexually mature female veiled chameleons (Chamaeleo calyptratus, VC). Of 60 clinically healthy female VC with continuous ovarian cycling and at least one confirmed cycle with FA over at least 1.5 years, 30 were selected for macroscopic evaluation of ovarian appearance and 7 were subjected to histology and immunohistology. While FA of previtellogenic follicles happened at a low rate, expected for a species with two germinal beds per ovary and polyautochronic reproductive pattern, atresia in the late vitellogenic stage affected entire generations of follicles, consequential to ovulatory failure. Histologically, no pathological processes were identified in any of the animals. Rather, three stages of FA (early, middle, late) were defined and vitellogenic follicles showed two distinct morphological types of FA: yolky and cystic. Yolky FA was found in 21/30 (70%) animals, while cystic FA co-occurred in 9/30 (30%) of the animals.

The Effect of Pulling and Twisting Forces on Chameleon Sequence Peptides.

Chameleon sequences are amino acid sequences found in several distinct configurations in experiment. They challenge our understanding of the link between sequence and structure, and provide insight into structural competition in proteins. Here, we study the energy landscapes for three such sequences, and interrogate how pulling and twisting forces impact the available structural ensembles. Chameleon sequences do not necessarily exhibit multiple structural ensembles on a multifunnel energy landscape when we consider them in isolation. The application of even small forces leads to drastic changes in the energy landscapes. For pulling forces, we observe transitions from helical to extended structures in a very small span of forces. For twisting forces, the picture is much more complex, and highly dependent on the magnitude and handedness of the applied force as well as the reference angle for the twist. Depending on these parameters, more complex and more simplistic energy landscapes are observed alongside more and less diverse structural ensembles. The impact of even small forces is significant, confirming their likely role in folding events. In addition, small forces exerted by the remaining scaffold of a protein may be sufficient to lead to the adoption of a specific structural ensemble by a chameleon sequence.

Color match analysis of single-shade and multi-shade composite resins using spectrophotometric and visual methods after bleaching.

The aim of this study is to evaluate the color match of the materials after the staining and bleaching procedures applied to the teeth restored with single-shade and multi-shade composite resins. Cavities prepared on the facial surface of human incisors were restored with two different composite resins. After 24 h, the color matching parameters between the initial filling-tooth of the samples were recorded. Then, the color measurements of the samples subjected to the coloring process were repeated. Each composite resin group was randomly divided into 2 subgroups and home and office bleaching methods were applied to the samples. After bleaching, color measurements were repeated. In terms of periods, a statistically significant difference was found in ΔE values 1 day and 28 days after bleaching (p<0.05). In addition, it was found that the color match between filling-tooth was generally weaker in Omnichroma material and after home bleaching.

Computed tomography of the coelomic cavity in healthy veiled chameleons (Chamaeleo calyptratus) and panther chameleons (Furcifer pardalis).

Background: Veiled chameleon (Chamaeleo calyptratus) and panther chameleon (Furcifer pardalis) are two of the most popular pet chameleons, and consequently, these species are frequently evaluated in veterinary practices. According to our review of the literature, normal computed tomography (CT) anatomy of these lizards has not been previously described. Aim: The purposes of this prospective study were to describe the normal CT anatomy of the coelomic organs in healthy patients and to provide normal reference values in these species. Methods: Seventeen clinically healthy veiled chameleons and 15 clinically healthy panther chameleons were included. All CT studies were performed with the chameleons under light anesthesia and positioned in sternal recumbency. Studies were performed with a 16-slice helical CT scanner with a slice thickness of 0.625 mm. The authors recorded qualitative and quantitative CT characteristics of the coelomic structures. Macroscopic cross-sectional anatomy was performed for comparison of the CT findings. Results: Heart, lungs, liver, including caudal vena cava, hepatic vessels, gallbladder, esophagus, stomach, intestines, gonads, fat bodies, kidneys, and urinary bladder could be visualized with CT. The spleen, pancreas, and adrenal glands could not be identified. Conclusion: This study provides a guide to the normal cross-sectional and computed tomographic anatomy of the coelomic cavity in veiled and panther chameleons. Our results could be used as a reference for future research studies or comparison of clinically ill patients.

De Novo Whole Genome Assemblies for Two Southern African Dwarf Chameleons (Bradypodion, Chamaeleonidae).

A complete and high-quality reference genome has become a fundamental tool for the study of functional, comparative, and evolutionary genomics. However, efforts to produce high-quality genomes for African taxa are lagging given the limited access to sufficient resources and technologies. The southern African dwarf chameleons (Bradypodion) are a relatively young lineage, with a large body of evidence demonstrating the highly adaptive capacity of these lizards. Bradypodion are known for their habitat specialization, with evidence of convergent phenotypes across the phylogeny. However, the underlying genetic architecture of these phenotypes remains unknown for Bradypodion, and without adequate genomic resources, many evolutionary questions cannot be answered. We present de novo assembled whole genomes for Bradypodion pumilum and Bradypodion ventrale, using Pacific Biosciences long-read sequencing data. BUSCO analysis revealed that 96.36% of single copy orthologs were present in the B. pumilum genome and 94% in B. ventrale. Moreover, these genomes boast scaffold N50 of 389.6 and 374.9 Mb, respectively. Based on a whole genome alignment of both Bradypodion genomes, B. pumilum is highly syntenic with B. ventrale. Furthermore, Bradypodion is also syntenic with Anolis lizards, despite the divergence between these lineages estimated to be nearly 170 Ma. Coalescent analysis of the genomic data also suggests that historical changes in effective population size for these species correspond to notable shifts in the southern African environment. These high-quality Bradypodion genome assemblies will support future research on the evolutionary history, diversification, and genetic underpinnings of adaptation in Bradypodion.

Deep fit_predic: a novel integrated pyramid dilation EfficientNet-B3 scheme for fitness prediction system.

This study introduces novel deep learning (DL) techniques for effective fitness prediction using a person's health data. Initially, pre-processing is performed in which data cleaning, one-hot encoding and data normalization are performed. The pre-processed data are then fed into the feature selection stage, where the useful features are extracted using the enhanced chameleon swarm (ECham-Sw) optimization technique. Then, a clustering process is performed using Minkowski integrated gravity center clustering (Min-GCC) to cluster the health profiles of each individual. Finally, the Pyramid Dilated EfficientNet-B3 (PyDi-EfficientNet-B3) technique is proposed to predict the fitness of each individual efficiently with enhanced accuracy of 99.8%.

Histomorphological, Histochemical and Ultrastructural Studies on the Healthy Liver of Yemen Veiled Chameleon (Chamaeleo calyptratus) in Southern Saudi Arabia / Estudios Histomorfológicos, Histoquímicos y Ultraestructurales en el Hígado Sano del Camaleón Velado de Yemen (Chamaeleo calyptratus) en el Sur de Arabia Saudita

SUMMARY: The livers of reptiles are being studied as a model for the link between the environment and hepatic tissue. There have been few investigations on the histology of reptile livers, and very few or no studies have examined the histology of liver of veiled chameleon (Chamaeleo calyptratus). This paper describes the histomorphological, histochemical and ultrastructural characterization of the liver of veiled chameleons in southern Saudi Arabia. Seven Chamaeleo calyptratus were captured in the summer season in Abha City, Aseer region, southern Saudi Arabia. Chamaeleon liver samples were processed for histomorphology, histochemistry and ultrastructure analyses. Morphologically liver of Chamaeleo calyptratus was observed as a large dark brown organ with lighter speckles, which represent melanin deposits. It located at the ventral part of abdominal cavity forward of the stomach. Its dimensions approximately were 3.7 x 2 cm. The liver was a bilobed organ divided into two lobes, right and left lobes. The right one was bigger than the others. The gallbladder was well developed and had an elongated shape, situated between the two lobes and contained the bile for the digestion. Microscopically, the liver was found to be covered by a thick layer of connective tissue, which formed the hepatic capsule. Hepatic parenchyma probably appeared in cross sections as hepatic glandular-like alveoli "acini" or follicular structures with various diameters, each acinus contains approximately four to six hepatocytes, surrounded by sinusoidal capillaries filled with abundant melanomacrophages, which are absent in birds and mammals. Melanomacrophages are common in the hepatic parenchyma's perisinusoidal areas, particularly near portal spaces. Hepatocytes are polyhedral or pyramidal with and mostly contained large, rounded nuclei mostly peripherally located, with prominent dark oval nucleoli. Some of nuclei are eccentric or central position. The cytoplasm appeared spongy or vacuolated and more eosinophilic when stained by hematoxylin-eosin and strongly reactive to PAS staining technique, indicating abundant glycogen content. The reticular fibers that surround hepatocytes, blood arteries, and sinusoids supported the hepatic parenchyma. The blood sinusoids are seen interspersed among hepatocytes of varying sizes. The sinusoidal lumen was bordered by flattened endothelial cells and includes elliptical nucleated erythrocytes and liver macrophages as phagocytes, which are also known as Kupffer cells. Branches of the portal vein, hepatic artery, small bile duct, and lymph vessels were detected in the hepatic portal area "tract" or triad which made up of connective. Hematopoietic tissue was observed in subcapsular region and portal triads. Ultrastructurally, the hepatocyte appeared polyhedric containing a single large rounded basal or eccentric vesicular nucleus with prominent nucleolus. Extensive network of rough endoplasmic reticulum (RER) often arranged in an array parallel to the nuclear membrane with many mitochondria, and Golgi apparatus were described. The cytoplasm contained glycogen granules, vesicles or vacuoles scattered throughout the cytoplasm especially at the apical region were reported. The bile canaliculi and the hepatic "Kupffer" cells were also discussed. This is the first study on the histological characterization of the healthy liver of Yemen veiled chameleon in southern Saudi Arabia. The findings reported here should be used as a reference to compare with the pathological abnormalities of the liver in this animal.

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Mechanomyography Signal Pattern Recognition of Knee and Ankle Movements Using Swarm Intelligence Algorithm-Based Feature Selection Methods.

Pattern recognition of lower-limb movements based on mechanomyography (MMG) signals has a certain application value in the study of wearable rehabilitation-training devices. In this paper, MMG feature selection methods based on a chameleon swarm algorithm (CSA) and a grasshopper optimization algorithm (GOA) are proposed for the pattern recognition of knee and ankle movements in the sitting and standing positions. Wireless multichannel MMG acquisition systems were designed and used to collect MMG movements from four sites on the subjects thighs. The relationship between the threshold values and classification accuracy was analyzed, and comparatively high recognition rates were obtained after redundant information was eliminated. When the threshold value rose, the recognition rates from the CSA fluctuated within a small range: up to 88.17% (sitting position) and 90.07% (standing position). However, the recognition rates from the GOA drop dramatically when increasing the threshold value. The comparison results demonstrated that using a GOA consumes less time and selects fewer features, while a CSA gives higher recognition rates of knee and ankle movements.

Efficient and Highly Continuous Chromosome-Level Genome Assembly of the First Chameleon Genome.

Most amniote genomes are diploid and moderate in size (∼1-6 Gbp) and contain a large proportion of repetitive sequences. The development of next-generation sequencing technology, especially the emergence of high-fidelity (HiFi) long-read data, has made it feasible to resolve high-quality genome assembly for nonmodel species efficiently. However, reference genomes for squamate reptiles have lagged behind other amniote lineages. Here, we de novo assembled the first genome from the Chameleonidae family, the panther chameleon (Furcifer pardalis). We obtained telomere-to-telomere contigs using only HiFi data, reaching a contig N50 of 158.72 Mbp. The final chromosome-level assembly is 1.61 Gbp in size, and 100% of primary contigs were placed to pseudochromosomes using Hi-C interaction data. We also found that sequencing depth > 30 folds can ensure both the integrity and accuracy of the genome, whereas insufficient depth led to false increase in genome size and proportion of duplicated genes. We provide a high-quality reference genome valuable for evolutionary and ecological studies in chameleons as well as provide comparative genomic resources for squamate reptiles.

Delays in the diagnosis of ischaemic stroke presenting with persistent reduced level of consciousness: A systematic review.

INTRODUCTION: Stroke presenting with a reduced level of consciousness (RLOC) may result in diagnostic error and/or delay. Missed or delayed diagnosis of acute ischaemic stroke may preclude otherwise applicable hyperacute stroke interventions. The frequency, reasons for, and consequences of diagnostic error and delay due to RLOC are uncertain. METHOD: The databases PubMed, EMBASE, and Cochrane library were searched in adherence with the PRISMA guidelines. The systematic review was prospectively registered on PROSPERO. RESULTS: Initial searches returned 1162 results, of which 6 fulfilled inclusion criteria. The majority of identified studies show that ischaemic stroke presenting with RLOC is at increased risk of missed or delayed diagnosis. Hyperacute stroke interventions may also be delayed. There is limited evidence regarding the reason for these delays; however, the delays may result from neuroimaging delay associated with diagnostic uncertainty. There is also limited evidence regarding the outcomes of patients with stroke and RLOC who experience diagnostic delay; however, the available literature suggests that outcomes may be poor, including motor and cognitive impairment, as well as long-term impaired consciousness. The included studies did not evaluate, but have suggested urgent MRI access, educational interventions, and protocolisation of the evaluation of RLOC as means to reduce poor outcomes. CONCLUSIONS: Ischaemic stroke patients with RLOC are at risk of diagnostic delay and error. These patients may have poor outcomes. Additional research is required to identify the contributing factors more clearly and to provide amelioration strategies.

A Dual Leucine-rich Repeat in Proteins from the Eukaryotic SAR Group.

BACKGROUND: Leucine-rich repeats (LRRs) occurring in tandem are 20-29 amino acids long. Eleven LRR types have been recognized; they include plant-specific (PS) type with the consensus of LxxLxLxxNxL SGxIPxxIxxLxx of 24 residues and SDS22-like type with the consensus of LxxLxLxxNxL xxIxxIxxLxx of 22 residues. OBJECTIVE: A viral LRR protein in metagenome data indicated that most of the LRRs (5/6 = 0.83) are represented by the consensus of LxxLDLxxTxV SGKLSDLxxLTN of 23 residues. This LRR shows a dual characteristic of PS and SDS22-like LRRs (called PS/SDS22-like LRR). A comprehensive similarity search was performed under the hypothesis that many proteins contain LRR domains consisting of only or mainly PS/SDS22-like LRR. METHODS: Sequence similarity search by the FASTA and BLAST programs was performed using the sequence of this PS/SDS22-like LRR domain as a query sequence. The presence of PS/SDS22-like LRR was screened within the LRR domains in known structures. RESULTS: Over 280 LRR proteins were identified from protists, fungi, and bacteria; ~ 40% come from the SAR group (the phyla Alveolate and Stramenopiles). The secondary structure analysis of PS/SDS22-like LRRs occurring sporadically in the known structures indicates three or four type patterns of secondary structures. CONCLUSION: PS/SDS22-like LRR forms an LRR class with PS, SDS22-like and Leptospira-like LRRs. It appears that PS/SDS22-like LRR is a chameleon-like sequence. A duality of two LRR types brings diversity.

Adaptive Density Spatial Clustering Method Fusing Chameleon Swarm Algorithm.

The density-based spatial clustering of application with noise (DBSCAN) algorithm is able to cluster arbitrarily structured datasets. However, the clustering result of this algorithm is exceptionally sensitive to the neighborhood radius (Eps) and noise points, and it is hard to obtain the best result quickly and accurately with it. To solve the above problems, we propose an adaptive DBSCAN method based on the chameleon swarm algorithm (CSA-DBSCAN). First, we take the clustering evaluation index of the DBSCNA algorithm as the objective function and use the chameleon swarm algorithm (CSA) to iteratively optimize the evaluation index value of the DBSCAN algorithm to obtain the best Eps value and clustering result. Then, we introduce the theory of deviation in the data point spatial distance of the nearest neighbor search mechanism to assign the identified noise points, which solves the problem of over-identification of the algorithm noise points. Finally, we construct color image superpixel information to improve the CSA-DBSCAN algorithm's performance regarding image segmentation. The simulation results of synthetic datasets, real-world datasets, and color images show that the CSA-DBSCAN algorithm can quickly find accurate clustering results and segment color images effectively. The CSA-DBSCAN algorithm has certain clustering effectiveness and practicality.

Morphological changes and two Nodal paralogs drive left-right asymmetry in the squamate veiled chameleon (C. calyptratus).

The ancestral mode of left-right (L-R) patterning involves cilia in the L-R organizer. However, the mechanisms regulating L-R patterning in non-avian reptiles remains an enigma, since most squamate embryos are undergoing organogenesis at oviposition. In contrast, veiled chameleon (Chamaeleo calyptratus) embryos are pre-gastrula at oviposition, making them an excellent organism for studying L-R patterning evolution. Here we show that veiled chameleon embryos lack motile cilia at the time of L-R asymmetry establishment. Thus, the loss of motile cilia in the L-R organizers is a synapomorphy of all reptiles. Furthermore, in contrast to avians, geckos and turtles, which have one Nodal gene, veiled chameleon exhibits expression of two paralogs of Nodal in the left lateral plate mesoderm, albeit in non-identical patterns. Using live imaging, we observed asymmetric morphological changes that precede, and likely trigger, asymmetric expression of the Nodal cascade. Thus, veiled chameleons are a new and unique model for studying the evolution of L-R patterning.

Chameleon Multienvironment Nanoreactors.

Nanoreactors consisting of hydrophilic porous SiO2 shells and amphiphilic copolymer cores have been prepared, which can easily self-tune their hydrophilic/hydrophobic balance depending on the environment and exhibit chameleon-like behavior. The accordingly obtained nanoparticles show excellent colloidal stability in a variety of solvents with different polarity. Most importantly, thanks to the assistance of the nitroxide radicals attached to the amphiphilic copolymers, the synthesized nanoreactors show high catalytic activity for model reactions in both polar and nonpolar environments and, more particularly, realize a high selectivity for the products resulting from the oxidation of benzyl alcohol in toluene.

Importin alpha family NAAT/IBB domain: Functions of a pleiotropic long chameleon sequence.

Nuclear transport is essential for eukaryotic cell survival and regulates the movement of functional molecules in and out of the nucleus via the nuclear pore. Transport is facilitated by protein-protein interactions between cargo and transport receptors, which contribute to the expression and regulation of downstream genetic information. This chapter focuses on the molecular basis of the multifunctional nature of the importin α family, the representative transport receptors that bring proteins into the nucleus. Importin α performs multiple functions during the nuclear transport cycle through interactions with multiple molecules by a single domain called the IBB domain. This domain is a long chameleon sequence, which can change its conformation and binding mode depending on the interaction partners. By considering the evolutionarily conserved biochemical/physicochemical propensities of the amino acids constituting the functional complex interfaces, together with their structural properties, the mechanisms of switching between multiple complexes formed via IBB and the regulation of downstream functions are examined in detail. The mechanism of regulation by IBB indicates that the time has come for a paradigm shift in the way we view the molecular mechanisms by which proteins regulate downstream functions through their interactions with other molecules.