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Asthma is a complex disease with varied clinical manifestations resulting from the interaction between environmental and genetic factors. While chronic airway inflammation and hyperresponsiveness are central features, the etiology of asthma is multifaceted, leading to a diversity of phenotypes and endotypes. Although most research into the genetics of asthma focused on the analysis of single nucleotide polymorphisms (SNPs), studies highlight the importance of structural variations, such as copy number variations (CNVs), in the inheritance of complex characteristics, but their role has not yet been fully elucidated in asthma. In this context, an integrative review was conducted to identify the genes and pathways involved, the location, size, and classes of CNVs, as well as their contribution to asthma risk, severity, control, and response to treatment. As a result of the review, 16 articles were analyzed, from different types of observational studies, such as case–control, cohort studies and genotyped-proband or trios design, that have been carried out in populations from different countries, ethnicities, and ages. Chromosomes 12 and 17 were the most studied in three publications each. CNVs located on 12 chromosomes were associated with asthma, the majority being found on chromosome 6p and 17q, of the deletion type, encompassing 30 different coding-protein genes and one pseudogene region. Six genes with CNVs were identified as significant expression quantitative locus (eQTLs) with mean expression in asthma-related tissues, such as the lung and whole blood. The phenotypic variability of asthma may hinder the clinical application of these findings, but the research shows the importance of investigating these genetic variations as possible biomarkers in asthma patients. [ABSTRACT FROM AUTHOR]

An analysis of some of the key issues raised, but left unresolved, by Beckett exposing the ways the (typically concealed) notion of identity is constructed and the non-concomitant representation(s) of surrogacy which develop from it in Malone Dies. Involved in both enterprises are fabrications of artifice, themselves very much vulnerable to differential inspiration, which are set over against, but apparently complicit with, a supposedly 'natural' continuity, with both subject to the presumed proximity of death. The coda of the novel, very much a 'codetta', demonstrates how imagined fact and imagined fiction can always be revised, but can never be made to cohere. Malone Dies is throughout seen either as (a) an investigation into whether the body can ever make up its mind when the mind can only partially accommodate the intrinsic shortcomings of the body, or as (b): a demonstration that what the notes for Film think of as 'merely structural and dramatic convenience' is very much subject to the inconvenient truth that there is always some 'deep common point of divergence' to which they can never be satisfactorily reduced; or as both in more or less equal measure. [ABSTRACT FROM AUTHOR]

Abstract Transposable elements (TEs) are a major force in the evolution of plant genomes. Differences in the transposition activities and landscapes of TEs can vary substantially, even in closely related species. Interspecific hybridization, a widely employed technique in tomato breeding, results in the creation of novel combinations of TEs from distinct species. The implications of this process for TE transposition activity have not been studied in modern cultivars. In this study, we used nanopore sequencing of extrachromosomal circular DNA (eccDNA) and identified two highly active Ty1/Copia LTR retrotransposon families of tomato (Solanum lycopersicum), called Salsa and Ketchup. Elements of these families produce thousands of eccDNAs under controlled conditions and epigenetic stress. EccDNA sequence analysis revealed that the major parts of eccDNA produced by Ketchup and Salsa exhibited low similarity to the S. lycopersicum genomic sequence. To trace the origin of these TEs, whole-genome nanopore sequencing and de novo genome assembly were performed. We found that these TEs occurred in a tomato breeding line via interspecific introgression from S. peruvianum. Our findings collectively show that interspecific introgressions can contribute to both genetic and phenotypic diversity not only by introducing novel genetic variants, but also by importing active transposable elements from other species.

Foreign bodies are objects that do not typically belong in the human body but can be ingested, inserted, or entered due to injuries. This article presents various cases and examples of foreign bodies, including objects swallowed, objects inserted into the rectum, vagina, urethra, ear, and nose, or due to injuries caused by falls, puncture wounds, and gunshot wounds. Foreign bodies can be difficult to detect, particularly if they are not inherently radio-opaque, and may be overlooked by patients who cannot provide an adequate history. These foreign bodies may cause harm to the patient. Interpretation is done on radiographs, computed tomography (CT), Ultrasonography (USG), and magnetic resonance imaging (MRI) studies. Most foreign objects pass through the gastrointestinal tract without problem; sharp and elongated objects can cause significant injury, and even if they only partially perforate the bowel wall, they can produce chronic inflammatory processes that produce symptoms months or years later. Hence, searching for foreign bodies should be done throughout the gastrointestinal tract, particularly in children and people with mental illness who are more likely to swallow multiple items more than once. Although rare, various materials can be left behind in the body of a patient after surgery, including large and small wire sutures, surgical drains, and retained sponges, which can cause potential complications and foreign body reactions. This article highlights the importance of being aware of the presence of foreign bodies in clinical practice, and a thorough search should be carried out using different modalities, especially CT. Great suspicion and early diagnosis of foreign bodies can avoid potential complications and morbidity. In general, it provides information on the diagnosis and treatment of various types of foreign bodies.

Transposable elements (TEs) are a major force in the evolution of plant genomes. Differences in the transposition activities and landscapes of TEs can vary substantially, even in closely related species. Interspecific hybridization, a widely employed technique in tomato breeding, results in the creation of novel combinations of TEs from distinct species. The implications of this process for TE transposition activity have not been studied in modern cultivars. In this study, we used nanopore sequencing of extrachromosomal circular DNA (eccDNA) and identified two highly active Ty1/Copia LTR retrotransposon families of tomato (Solanum lycopersicum), called Salsa and Ketchup. Elements of these families produce thousands of eccDNAs under controlled conditions and epigenetic stress. EccDNA sequence analysis revealed that the major parts of eccDNA produced by Ketchup and Salsa exhibited low similarity to the S. lycopersicum genomic sequence. To trace the origin of these TEs, whole-genome nanopore sequencing and de novo genome assembly were performed. We found that these TEs occurred in a tomato breeding line via interspecific introgression from S. peruvianum. Our findings collectively show that interspecific introgressions can contribute to both genetic and phenotypic diversity not only by introducing novel genetic variants, but also by importing active transposable elements from other species. [ABSTRACT FROM AUTHOR]

Foreign bodies are objects that do not typically belong in the human body but can be ingested, inserted, or entered due to injuries. This article presents various cases and examples of foreign bodies, including objects swallowed, objects inserted into the rectum, vagina, urethra, ear, and nose, or due to injuries caused by falls, puncture wounds, and gunshot wounds. Foreign bodies can be difficult to detect, particularly if they are not inherently radio-opaque, and may be overlooked by patients who cannot provide an adequate history. These foreign bodies may cause harm to the patient. Interpretation is done on radiographs, computed tomography (CT), Ultrasonography (USG), and magnetic resonance imaging (MRI) studies. Most foreign objects pass through the gastrointestinal tract without problem; sharp and elongated objects can cause significant injury, and even if they only partially perforate the bowel wall, they can produce chronic inflammatory processes that produce symptoms months or years later. Hence, searching for foreign bodies should be done throughout the gastrointestinal tract, particularly in children and people with mental illness who are more likely to swallow multiple items more than once. Although rare, various materials can be left behind in the body of a patient after surgery, including large and small wire sutures, surgical drains, and retained sponges, which can cause potential complications and foreign body reactions. This article highlights the importance of being aware of the presence of foreign bodies in clinical practice, and a thorough search should be carried out using different modalities, especially CT. Great suspicion and early diagnosis of foreign bodies can avoid potential complications and morbidity. In general, it provides information on the diagnosis and treatment of various types of foreign bodies.

The study of potential-dependent calcium channels sheds light on the formation of systems responsible for the coupling of sensors and actuators in a living cell. Based on data on the potential-sensitive calcium channel TCav3 (2063 amino acid residues) from Trichoplax adhaerens cells, homologues of 2090 amino acid residues in the scaffold of Trichoplax sp. H2 and an incomplete polypeptide with a length of 1510 amino acid residues in the scaffold of Trichoplax adhaerens are identified. The latter hypothetical protein is annotated as a Cav3 channel. An EEDD selective filter is found for all three proteins and the core structure of the calcium channel consisting of 24 transmembrane α-helices is reconstructed. Nevertheless, the studied proteins differ in cytoplasmic domains, which indicates a different specialization of Cav3 channels when conducting a signal into the cell. For example, part of the AID motif (alpha-interacting domain) and the adjacent potential sensor from the annotated channel have homology in 25 species of bony fish, and the corresponding region from other channels in 41 species of bony fish and in 4 species of snakes. Significantly, a highly conserved IIS1-S2 loop with the IEHHNQP sequence is found below the AID motif of bony fish, as in trichoplax; while a homologous IEHHEQP sequence is found in snakes, characterized by a negative glutamic acid residue, which is also present in the corresponding rat and human proteins. Based on the analysis of primary transcripts and mature polypeptides, a modular mechanism for the evolution of Cav3 channels is proposed by inserting and combining protein domains performing various regulatory functions. [ABSTRACT FROM AUTHOR]

The protonation, or Lewis Acid complexation, of electrophiles can trigger the sequential insertion of two or more isocyanides resulting in valuable iminonitriles or heterocycles. The number of insertions is controlled by the nature of the alkyl- or arylisocyanide and by the presence of a proximal nucleophile capable of attacking the intermediate nitrilium; loss of an alkyl group from the nitrilium or attack by a nucleophile terminates further isocyanide insertions. The mechanistic survey of protic and Lewis acid-promoted isocyanide insertions aims to provide a fundamental understanding of the reactivity and selectivity to facilitate synthetic applications. The review is structured with an introductory overview followed by a mechanistic analysis before moving to a survey of double insertions, which are the most prevalent, then triple insertions; the survey concludes with the sole example of a quadruple insertion. The hope is that the insight contained in the review will aid in applying protic and Lewis acid-activated isocyanide insertions to prepare an array of complex heterocycles.

Pulsed thermography has been applied to the quantitative characterization of the insertions of two ancient bronzes, the Boxer at Rest and the Hellenistic Prince. The analysis of the thermographic signal time dependence performed by a specifically developed model enabled the evaluation of the insertions' thickness and of elements which could provide indications about the procedure followed for their insertion. This could be achieved by exploiting a semi‐empirical relation establishing the thermal diffusivity dependence on the total effective weighted concentration of Sn and Pb atoms obtained from the analysis of the values determined on samples containing different concentrations of Sn and Pb. [ABSTRACT FROM AUTHOR]

Foreign bodies are objects that do not typically belong in the human body but can be ingested, inserted, or entered due to injuries. This article presents various cases and examples of foreign bodies, including objects swallowed, objects inserted into the rectum, vagina, urethra, ear, and nose, or due to injuries caused by falls, puncture wounds, and gunshot wounds. Foreign bodies can be difficult to detect, particularly if they are not inherently radio-opaque, and may be overlooked by patients who cannot provide an adequate history. These foreign bodies may cause harm to the patient. Interpretation is done on radiographs, computed tomography (CT), Ultrasonography (USG), and magnetic resonance imaging (MRI) studies. Most foreign objects pass through the gastrointestinal tract without problem; sharp and elongated objects can cause significant injury, and even if they only partially perforate the bowel wall, they can produce chronic inflammatory processes that produce symptoms months or years later. Hence, searching for foreign bodies should be done throughout the gastrointestinal tract, particularly in children and people with mental illness who are more likely to swallow multiple items more than once. Although rare, various materials can be left behind in the body of a patient after surgery, including large and small wire sutures, surgical drains, and retained sponges, which can cause potential complications and foreign body reactions. This article highlights the importance of being aware of the presence of foreign bodies in clinical practice, and a thorough search should be carried out using different modalities, especially CT. Great suspicion and early diagnosis of foreign bodies can avoid potential complications and morbidity. In general, it provides information on the diagnosis and treatment of various types of foreign bodies.

Abstract Background Long-read sequencing technologies have the potential to overcome the limitations of short reads and provide a comprehensive picture of the human genome. However, the characterization of repetitive sequences by reconstructing genomic structures at high resolution solely from long reads remains difficult. Here, we developed a localized assembly method (LoMA) that constructs highly accurate consensus sequences (CSs) from long reads. Methods We developed LoMA by combining minimap2, MAFFT, and our algorithm, which classifies diploid haplotypes based on structural variants and CSs. Using this tool, we analyzed two human samples (NA18943 and NA19240) sequenced with the Oxford Nanopore sequencer. We defined target regions in each genome based on mapping patterns and then constructed a high-quality catalog of the human insertion solely from the long-read data. Results The assessment of LoMA showed a high accuracy of CSs (error rate 8%) and superiority to a previous study. The genome-wide analysis of NA18943 and NA19240 identified 5516 and 6542 insertions (≥ 100 bp), respectively. Most insertions (~ 80%) were derived from tandem repeats and transposable elements. We also detected processed pseudogenes, insertions in transposable elements, and long insertions (> 10 kbp). Finally, our analysis suggested that short tandem duplications are associated with gene expression and transposons. Conclusions Our analysis showed that LoMA constructs high-quality sequences from long reads with substantial errors. This study revealed the true structures of the insertions with high accuracy and inferred the mechanisms for the insertions, thus contributing to future human genome studies. LoMA is available at our GitHub page: https://github.com/kolikem/loma .

Simple Summary: A tiny human sample is enough to uncover the complete genome sequence of that individual with the advances in biomedical technologies and data analysis. Jumping genes constituting about half of the human genome, have been implicated in cancer and predisposition to inflammatory reactions. Inflammation may restrict the activity of these genes and reduce the tumor burden. This article summarizes related literature on factors regulating jumping genes and discusses their immune-related evidence made available by genome-wide studies. Advances in sequencing technologies and the bioinformatic analysis of big data facilitate the study of jumping genes' activity in the human genome in cancer from a broad perspective. Retrotransposons, which move from one genomic site to another by a copy-and-paste mechanism, are regulated by various molecular pathways that may be disrupted during tumorigenesis. Active retrotransposons can stimulate type I IFN responses. Although accumulated evidence suggests that retrotransposons can induce inflammation, the research investigating the exact mechanism of triggering these responses is ongoing. Understanding these mechanisms could improve the therapeutic management of cancer through the use of retrotransposon-induced inflammation as a tool to instigate immune responses to tumors. [ABSTRACT FROM AUTHOR]

BACKGROUND:Glucocorticoids are commonly used in the clinical setting for their potent anti-inflammatory effects; however, significant variations in response to treatment have been demonstrated. Although the underlying mechanisms have yet to be fully understood, this variable response may be a result of alterations in human glucocorticoid receptor (hGR) expression and function. In addition to hGRα, the biologically active isoform, a screening of current databases and publications revealed five alternative splice isoforms and hundreds of variants that have been reported to date. Many of these changes in the hGR-coding gene, NR3C1, have been linked to pathophysiology. However, many studies focus on evaluating hGR expression in vitro or detecting previously reported variants. RESULTS:In this study, blood from healthy volunteers, burn and asthma patients, as well as from peripheral blood mononuclear cells isolated from leukoreduced donor whole blood, were screened for NR3C1 isoforms. We identified more than 1500 variants, including an additional 21 unique splice isoforms which contain 15 new cryptic exons. A dynamic database, named the Universal hGR (UhGR), was created to annotate and visualize the variants. CONCLUSION:This identification of naturally occurring and stress-induced hGR isoforms, as well as the establishment of an hGR-specific database, may reveal new patterns or suggest areas of interest that will lead to the improved understanding of the human stress response system.

High-throughput genomic and phenomic data have enhanced the ability to detect genotype-to-phenotype associations that can resolve broad pleiotropic effects of mutations on plant phenotypes. As the scale of genotyping and phenotyping has advanced, rigorous methodologies have been developed to accommodate larger datasets and maintain statistical precision. However, determining the functional effects of associated genes/loci is expensive and limited due to the complexity associated with cloning and subsequent characterization. Here, we utilized phenomic imputation of a multi-year, multi-environment dataset using PHENIX which imputes missing data using kinship and correlated traits, and we screened insertions and deletions (InDels) from the recently whole-genome sequenced Sorghum Association Panel for putative loss-of-function effects. Candidate loci from genome-wide association results were screened for potential loss of function using a Bayesian Genome-Phenome Wide Association Study (BGPWAS) model across both functionally characterized and uncharacterized loci. Our approach is designed to facilitate in silico validation of associations beyond traditional candidate gene and literature-search approaches and to facilitate the identification of putative variants for functional analysis and reduce the incidence of false-positive candidates in current functional validation methods. Using this Bayesian GPWAS model, we identified associations for previously characterized genes with known loss-of-function alleles, specific genes falling within known quantitative trait loci, and genes without any previous genomewide associations while additionally detecting putative pleiotropic effects. In particular, we were able to identify the major tannin haplotypes at the Tan1 locus and effects of InDels on the protein folding. Depending on the haplotype present, heterodimer formation with Tan2 was significantly affected. We also identified major effect InDels in Dw2 and Ma1, where proteins were truncated due to frameshift mutations that resulted in early stop codons. These truncated proteins also lost most of their functional domains, suggesting that these indels likely result in loss of function. Here, we show that the Bayesian GPWAS model is able to identify loss-of-function alleles that can have significant effects upon protein structure and folding as well as multimer formation. Our approach to characterize loss-of-function mutations and their functional repercussions will facilitate precision genomics and breeding by identifying key targets for gene editing and trait integration. [ABSTRACT FROM AUTHOR]

Background: Long-read sequencing technologies have the potential to overcome the limitations of short reads and provide a comprehensive picture of the human genome. However, the characterization of repetitive sequences by reconstructing genomic structures at high resolution solely from long reads remains difficult. Here, we developed a localized assembly method (LoMA) that constructs highly accurate consensus sequences (CSs) from long reads. Methods: We developed LoMA by combining minimap2, MAFFT, and our algorithm, which classifies diploid haplotypes based on structural variants and CSs. Using this tool, we analyzed two human samples (NA18943 and NA19240) sequenced with the Oxford Nanopore sequencer. We defined target regions in each genome based on mapping patterns and then constructed a high-quality catalog of the human insertion solely from the long-read data. Results: The assessment of LoMA showed a high accuracy of CSs (error rate < 0.3%) compared with raw data (error rate > 8%) and superiority to a previous study. The genome-wide analysis of NA18943 and NA19240 identified 5516 and 6542 insertions (≥ 100 bp), respectively. Most insertions (~ 80%) were derived from tandem repeats and transposable elements. We also detected processed pseudogenes, insertions in transposable elements, and long insertions (> 10 kbp). Finally, our analysis suggested that short tandem duplications are associated with gene expression and transposons. Conclusions: Our analysis showed that LoMA constructs high-quality sequences from long reads with substantial errors. This study revealed the true structures of the insertions with high accuracy and inferred the mechanisms for the insertions, thus contributing to future human genome studies. LoMA is available at our GitHub page: https://github.com/kolikem/loma. [ABSTRACT FROM AUTHOR]

We discuss substitution as a further type of operation, added to (in particular, one-sided) insertion-deletion systems and investigate the effect of such an addition. Does this operation increase the computational power of a given class of insertion-deletion systems and if so, by what extent does the computational power increase? With the help of substitutions, we obtain new characterizations of the classes of context-sensitive and recursively enumerable languages. We present new normal forms for type-0 grammars that could be of independent interest. Moreover, insertion-deletion-substitution systems can describe new families of languages that contain all regular languages or that are contained in the class of context-free languages. [ABSTRACT FROM AUTHOR]

LINE-1 (L1) and Alu are two families of transposable elements (TEs) occupying ~17% and ~11% of the human genome, respectively. Though only a small fraction of L1 copies is able to produce the machinery to mobilize autonomously, Alu and degenerate L1s can hijack their functional machinery and mobilize in trans . The expression and subsequent mobilization of L1 and Alu can exert pathological effects on their hosts. These features have made them promising focus subjects in studies of aging where they can become active. However, mechanisms regulating TE activity are incompletely characterized, especially in diverse human populations. To address these gaps, we leveraged genomic data from the 1000 Genomes Project to carry out a trans-ethnic GWAS of L1/Alu insertion singletons. These are rare, recently acquired insertions observed in only one person and which we used as proxies for variation in L1/Alu insertion numbers. Our approach identified SNVs in genomic regions containing genes with potential and known TE regulatory properties, and it enriched for SNVs in regions containing known regulators of L1 expression. Moreover, we identified reference TE copies and structural variants that associated with L1/Alu singletons, suggesting their potential contribution to TE insertion number variation. Finally, a transcriptional analysis of lymphoblastoid cells highlighted potential cell cycle alterations in a subset of samples harboring L1/Alu singletons. Collectively, our results suggest that known TE regulatory mechanisms may be active in diverse human populations, expand the list of loci implicated in TE insertion number variability, and reinforce links between TEs and disease., Competing Interests: Competing interests The authors declare that they have no competing interests.

Background/aim: Epidermal growth factor receptor (EGFR) exon 19 insertions are very rare mutations and their response to tyrosine kinase inhibitors (TKIs) is uncertain. We report our experience concerning two patients, along with a literature review., Patients and Methods: A total of 1,046 non-small-cell lung cancer tumor tissue samples were screened for EGFR mutations, using direct sequencing or next-generation sequencing. Two patients presented the same insertion of 18 nucleotides in EGFR exon 19 and were treated with afatinib., Results: Both patients responded to afatinib, showing a stable disease (SD) and a progression-free survival (PFS) of 6 and 10 months along with an overall survival (OS) of 17 and 19 months, respectively. A review of the literature data concerning clinical responsiveness to different generations of TKIs in patients with EGFR exon 19 insertions, including data of our two patients (n=28), showed a response rate of 64% and disease control rate of 92%. The calculated median PFS for the 28 cases, independently of the TKIs administered, was 9 months; median OS (n=15) was 13 months. Median PFS for patients receiving gefitinib and erlotinib was 9 months and 12.5 months, respectively, consistent with the median PFS observed in patients with "classical" EGFR mutations, treated with these agents., Conclusion: Patients with EGFR insertions in exon 19 have demonstrated sensitivity to treatment with EGFR TKIs, suggesting that patients carrying these mutations should be treated with these inhibitors., (Copyright © 2025 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

High-throughput genomic and phenomic data have enhanced the ability to detect genotype-to-phenotype associations that can resolve broad pleiotropic effects of mutations on plant phenotypes. As the scale of genotyping and phenotyping has advanced, rigorous methodologies have been developed to accommodate larger datasets and maintain statistical precision. However, determining the functional effects of associated genes/loci is expensive and limited due to the complexity associated with cloning and subsequent characterization. Here, we utilized phenomic imputation of a multi-year, multi-environment dataset using PHENIX which imputes missing data using kinship and correlated traits, and we screened insertions and deletions (InDels) from the recently whole-genome sequenced Sorghum Association Panel for putative loss-of-function effects. Candidate loci from genome-wide association results were screened for potential loss of function using a Bayesian Genome-Phenome Wide Association Study (BGPWAS) model across both functionally characterized and uncharacterized loci. Our approach is designed to facilitate in silico validation of associations beyond traditional candidate gene and literature-search approaches and to facilitate the identification of putative variants for functional analysis and reduce the incidence of false-positive candidates in current functional validation methods. Using this Bayesian GPWAS model, we identified associations for previously characterized genes with known loss-of-function alleles, specific genes falling within known quantitative trait loci, and genes without any previous genome-wide associations while additionally detecting putative pleiotropic effects. In particular, we were able to identify the major tannin haplotypes at the Tan1 locus and effects of InDels on the protein folding. Depending on the haplotype present, heterodimer formation with Tan2 was significantly affected. We also identified major effect InDels in Dw2 and Ma1, where proteins were truncated due to frameshift mutations that resulted in early stop codons. These truncated proteins also lost most of their functional domains, suggesting that these indels likely result in loss of function. Here, we show that the Bayesian GPWAS model is able to identify loss-of-function alleles that can have significant effects upon protein structure and folding as well as multimer formation. Our approach to characterize loss-of-function mutations and their functional repercussions will facilitate precision genomics and breeding by identifying key targets for gene editing and trait integration.

Chronic hepatitis B (CHB) is caused by hepatitis B virus (HBV) infection. This disease is a key issue for global health. Modern methods of therapy do not completely eliminate HBV from infected cells and do not cure chronic infection. The CRISPR/Cas9 systems of site-specific nucleases can effectively cleave do not target DNA including viral genomes. The cleavage of the major form of the HBV genome, i.e., covalently closed circular DNA (cccDNA), leads to a robust reduction in viral replication and degradation or mutational inactivation of cccDNA. CRISPR/Cas9-based approaches are one of the most promising ways to achieve a 'sterilizing' cure of CHB, i.e., complete elimination of the virus from the body. Here, the HBV mouse model in vivo has been used to analyze the antiviral activity of the high-specific Cas9 protein and sgRNA targeting HBV genome. We have found that a single injection of short-lived ribonucleoprotein complexes of CRISPR/Cas9 results in a ~10-fold reduction in HBV DNA levels in the serum and liver of mice as early as 48 h after the start of the experiment. The remaining HBV DNAs have been found to harbor rare indel mutations. Developing new antivirals for treating CHB based on CRISPR/Cas9 ribonucleoprotein complexes could substantially reduce the duration of CHB therapy and, potentially, achieve complete elimination of viral infection. [ABSTRACT FROM AUTHOR]

Microsatellite sequences are particularly prone to slippage during DNA replication, forming insertion-deletion loops that, if left unrepaired, result in de novo mutations (expansions or contractions of the repeat array). Mismatch repair (MMR) is a critical DNA repair mechanism that corrects these insertion-deletion loops, thereby maintaining microsatellite stability. MMR deficiency gives rise to the molecular phenotype known as microsatellite instability (MSI). By sequencing MMR-proficient and -deficient (Mlh1+/+ and Mlh1−/−) single-cell exomes from mouse T cells, we reveal here several previously unrecognized features of in vivo MSI. Specifically, mutational dynamics of insertions and deletions were different on multiple levels. Factors that associated with propensity of mononucleotide microsatellites to insertions versus deletions were: microsatellite length, nucleotide composition of the mononucleotide tract, gene length and transcriptional status, as well replication timing. Here, we show on a single-cell level that deletions — the predominant MSI type in MMR-deficient cells — are preferentially associated with longer A/T tracts, long or transcribed genes and later-replicating genes. [ABSTRACT FROM AUTHOR]

A vast diversity of 16 influenza hemagglutinin (HA) subtypes are found in birds. Interestingly, viruses from only two subtypes, H5 and H7, have so far evolved into highly pathogenic avian influenza viruses (HPAIVs) following insertions or substitutions at the HA cleavage site by the viral polymerase. The mechanisms underlying this striking subtype specificity are still unknown. Here, we compiled a comprehensive dataset of 20,488 avian influenza virus HA sequences to investigate differences in nucleotide and amino acid usage at the HA cleavage site between subtypes and how these might impact the genesis of HPAIVs by polymerase stuttering and realignment. We found that sequences of the H5 and H7 subtypes stand out by their high purine content at the HA cleavage site. In addition, fewer substitutions were necessary in H5 and H7 HAs than in HAs from other subtypes to acquire an insertion-prone HA cleavage site sequence, as defined based on in vitro and in vivo data from the literature. Codon usage was more favorable for HPAIV genesis in sequences of viruses isolated from species or geographical regions in which HPAIV genesis is more frequently observed in nature. The results of the present analyses suggest that the subtype restriction of HPAIV genesis to H5 and H7 influenza viruses might be due to the particular codon usage at the HA cleavage site in these subtypes. [ABSTRACT FROM AUTHOR]

Induced pluripotent stem cells (iPSCs) hold great potential for regenerative medicine. By reprogramming a patient′s own cells, immunological rejection can be avoided during transplantation. For expansion and gene editing, iPSCs are grown in artificial culture for extended times. Culture affords potential danger for the accumulation of genetic aberrations. To study these, two induced pluripotent stem (iPS) cell lines were cultured and periodically analyzed using advanced optical mapping to detect and classify chromosome numerical and segmental changes that included deletions, insertions, balanced translocations and inversions. In one of the lines, a population trisomic for chromosome 12 gained dominance over a small number of passages. This appearance and dominance of the culture by chromosome 12 trisomic cells was tracked through intermediate passages by the analysis of chromosome spreads. Mathematical modeling suggested that the proliferation rates of diploid versus trisomic cells could not account for the rapid dominance of the trisomic population. In addition, optical mapping revealed hundreds of structural variations distinct from those generally found within the human population. Many of these structural variants were detected in samples obtained early in the culturing process and were maintained in late passage samples, while others were acquired over the course of culturing. [ABSTRACT FROM AUTHOR]

Abstract Background Comparative chloroplast genomics could shed light on the major evolutionary events that established plastomic diversity among closely related species. The Polypodiaceae family is one of the most species-rich and underexplored groups of extant ferns. It is generally recognized that the plastomes of Polypodiaceae are highly notable in terms of their organizational stability. Hence, no research has yet been conducted on genomic structural variation in the Polypodiaceae. Results The complete plastome sequences of Neolepisorus fortunei, Neolepisorus ovatus, and Phymatosorus cuspidatus were determined based on next-generation sequencing. Together with published plastomes, a comparative analysis of the fine structure of Polypodiaceae plastomes was carried out. The results indicated that the plastomes of Polypodiaceae are not as conservative as previously assumed. The size of the plastomes varies greatly in the Polypodiaceae, and the large insertion fragments present in the genome could be the main factor affecting the genome length. The plastome of Selliguea yakushimensis exhibits prominent features including not only a large-scale IR expansion exceeding several kb but also a unique inversion. Furthermore, gene contents, SSRs, dispersed repeats, and mutational hotspot regions were identified in the plastomes of the Polypodiaceae. Although dispersed repeats are not abundant in the plastomes of Polypodiaceae, we found that the large insertions that occur in different species are mobile and are always adjacent to repeated hotspot regions. Conclusions Our results reveal that the plastomes of Polypodiaceae are dynamic molecules, rather than constituting static genomes as previously thought. The dispersed repeats flanking insertion sequences contribute to the repair mechanism induced by double-strand breaks and are probably a major driver of structural evolution in the plastomes of Polypodiaceae.

[Display omitted] • Experimental evidence of distributing heat to enhance solar chimney flow. • Insertion method increased the stack flow rate in chimneys by 60% • Stratified model predicts the maximum flow potential of solar chimney. • Plume model predicted well the flow of solar chimneys without insertion. • Number of insertions is more important than the uniformity of the heat distribution. This study examined an innovative approach to enhancing solar chimney effect of using solar energy for building ventilation. Solar absorbing plates were inserted in a solar chimney to form a distributed heating flux among walls and insertions. Experiments using electrical heating to simulate the solar irradiation showed that adding two insertions increased the mass flow rate by 30%. The experimental data validated a computational fluid dynamics (CFD) model and two analytical models from the literature. Among these models, the plume model predicted the flow rate in the absence of insertions with reasonable accuracy, while the stratified model predicted the theoretical maximum flow rate instead of actual flow rate. The difference in flow rate between the two analytical models represents the potential for enhancement. The CFD simulations indicated that the insertion method could achieve approximately 70% of this potential. This represents a 57% increase in flow rate over the base case without insertions. This was achieved with 15 insertions. Adding more insertions was not advantageous because of the increase in friction. Insertions increase the uniformity of the heat distribution across the chimney channel and reduce the maximum temperature, resulting in a more uniform temperature distribution across the channel and, consequently, an increased buoyancy effect. However, two or three insertions are likely the most cost-effective in practice, as three insertions can realize majority (57%) of the potential enhancement. This study proves the concept of improving the efficiency of a solar chimney by adding transparent glazing insertions in the channel. [ABSTRACT FROM AUTHOR]

Deletions in the 3′ end region of the hepatitis B virus (HBV) X open reading frame (HBX) may affect the core promoter (Cp) and have been frequently associated with hepatocellular carcinoma (HCC). The aim of this study was to investigate the presence of variants with deletions and/or insertions (Indels) in this region in the quasispecies of 50 chronic hepatitis B (CHB) patients without HCC. We identified 103 different Indels in 47 (94%) patients, in a median of 3.4% of their reads (IQR, 1.3–8.4%), and 25% (IQR, 13.1–40.7%) of unique sequences identified in each quasispecies (haplotypes). Of those Indels, 101 (98.1%) caused 44 different altered stop codons, the most commonly observed were at positions 128, 129, 135, and 362 (putative position). Moreover, 39 (37.9%) Indels altered the TATA-like box (TA) sequences of Cp; the most commonly observed caused TA2 + TA3 fusion, creating a new putative canonical TATA box. Four (8%) patients developed negative clinical outcomes after a median follow-up of 9.4 (8.7–12) years. In conclusion, we observed variants with Indels in the HBX 3′ end in the vast majority of our CHB patients, some of them encoding alternative versions of HBx with potential functional roles, and/or alterations in the regulation of transcription. [ABSTRACT FROM AUTHOR]

Abstract Background Since 2009, numerous tools have been developed to detect structural variants using short read technologies. Insertions >50 bp are one of the hardest type to discover and are drastically underrepresented in gold standard variant callsets. The advent of long read technologies has completely changed the situation. In 2019, two independent cross technologies studies have published the most complete variant callsets with sequence resolved insertions in human individuals. Among the reported insertions, only 17 to 28% could be discovered with short-read based tools. Results In this work, we performed an in-depth analysis of these unprecedented insertion callsets in order to investigate the causes of such failures. We have first established a precise classification of insertion variants according to four layers of characterization: the nature and size of the inserted sequence, the genomic context of the insertion site and the breakpoint junction complexity. Because these levels are intertwined, we then used simulations to characterize the impact of each complexity factor on the recall of several structural variant callers. We showed that most reported insertions exhibited characteristics that may interfere with their discovery: 63% were tandem repeat expansions, 38% contained homology larger than 10 bp within their breakpoint junctions and 70% were located in simple repeats. Consequently, the recall of short-read based variant callers was significantly lower for such insertions (6% for tandem repeats vs 56% for mobile element insertions). Simulations showed that the most impacting factor was the insertion type rather than the genomic context, with various difficulties being handled differently among the tested structural variant callers, and they highlighted the lack of sequence resolution for most insertion calls. Conclusions Our results explain the low recall by pointing out several difficulty factors among the observed insertion features and provide avenues for improving SV caller algorithms and their combinations.

A comparison of the genomic sequences of F. tularensis subsp. tularensis, holarctica, and mediasiatica, subspecies of tularaemia pathogen virulent for human and animals, revealed a high (up to 99.26–99.8%) homology between their genomes. Every year, a new improved whole-genome phylogeny is suggested, in particular, for F. tularensis subsp. holarctica, a subspecies that shows low genetic diversity and is widely distributed worldwide. This limited genetic variation observed in F. tularensis subsp. holarctica genomes makes sequencing, along with tandem repeat number analysis (TRNA) and identification of single nucleotide substitutions (SNPs) and insertions and deletion (InDels), a preferable genetic tool for molecular typing of strains within the subspecies. The current F. tularensis subsp. holarctica strain genotyping pipeline separates four major phylogenetic groups (B.4, B.6, B.12, and B.16) and more than 300 individual genotypic populations within this subspecies, which differ by several specific single nucleotide substitutions and deletions. [ABSTRACT FROM AUTHOR]

The sequence reconstruction problem, introduced by Levenshtein in 2001, considers a communication scenario where the sender transmits a codeword from some codebook and the receiver obtains multiple noisy reads of the codeword. The common setup assumes the codebook to be the entire space and the problem is to determine the minimum number of distinct reads that is required to reconstruct the transmitted codeword. Motivated by modern storage devices, we study a variant of the problem where the number of noisy reads $N$ is fixed. Specifically, we design reconstruction codes that reconstruct a codeword from $N$ distinct noisy reads. We focus on channels that introduce a single edit error (i.e. a single substitution, insertion, or deletion) and their variants, and design reconstruction codes for all values of $N$. In particular, for the case of a single edit, we show that as the number of noisy reads increases, the number of redundant symbols required can be gracefully reduced from $\log _{q} n+O(1)$ to $\log _{q} \log _{q} n+O(1)$ , and then to $O(1)$ , where $n$ denotes the length of a codeword. We also show that these reconstruction codes are asymptotically optimal. Finally, via computer simulations, we demonstrate that in certain cases, reconstruction codes can achieve similar performance as classical error-correcting codes with less redundant symbols. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the addition of substitutions as a further type of operations to (in particular, context-free) insertion-deletion systems, i.e., in addition to insertions and deletions we allow single letter replacements to occur. We investigate the effect of the addition of substitution rules on the context dependency of such systems, thereby also obtaining new characterizations of and even normal forms for context-sensitive (CS) and recursively enumerable (RE) languages and their phrase-structure grammars. More specifically, we prove that for each RE language, there is a system generating this language that only inserts and deletes strings of length two without considering the context of the insertion or deletion site, but which may change symbols (by a substitution operation) by checking a single symbol to the left of the substitution site. When we allow checking left and right single-letter context in substitutions, even context-free insertions and deletions of single letters suffice to reach computational completeness. When allowing context-free insertions only, checking left and right single-letter context in substitutions gives a new characterization of CS. This clearly shows the power of this new type of rules. [ABSTRACT FROM AUTHOR]

SARS-CoV-2, which causes the current pandemic of respiratory illness, is evolving continuously and generating new variants. Nevertheless, most of the sequence analyses thus far focused on nucleotide substitutions despite the fact that insertions and deletions (indels) are equally important in the evolution of SARS-CoV-2. In this study, we analyzed 1,099,664 high-quality sequences of SARS-CoV-2 genomes to re-construct the evolutionary and epidemiological histories of indels. Our analysis revealed 289 circulating indel types (237 deletion and 52 insertion types, each represented by more than ten genomic sequences), among which eighteen were recurrent indel types, each represented by more than 500 genome sequences. Although indels were identified across the entire genome, most of them were identified in nsp6, S, ORF8, and N genes, among which ORF8 indel types had the highest frequencies of frameshift. Geographical and temporal analyses of these variants revealed a few alterations of dominant indel types, each accompanied by geographic expansion to different countries and continents, which resulted in the fixation of several types of indels in the field, including the current variants of concern. Evolutionary and structural analyses revealed that indels involving S N-terminal domain regions were linked to the 3/4 variants of concern, resulting in significantly altered S protein that might contribute to the selective advantage of the corresponding variant. In sum, our study highlights the important role of insertions and deletions in the evolution and spread of SARS-CoV-2. [ABSTRACT FROM AUTHOR]

The inversion distance, that is the distance between two unichromosomal genomes with the same content allowing only inversions of DNA segments, can be exactly computed thanks to a pioneering approach of Hannenhalli and Pevzner from 1995. In 2000, El-Mabrouk extended the inversion model to perform the comparison of unichromosomal genomes with unequal contents, combining inversions with insertions and deletions (indels) of DNA segments, giving rise to the inversion-indel distance. However, only a heuristic was provided for its computation. In 2005, Yancopoulos, Attie and Friedberg started a new branch of research by introducing the generic double cut and join (DCJ) operation, that can represent several genome rearrangements (including inversions). In 2006, Bergeron, Mixtacki and Stoye showed that the DCJ distance can be computed in linear time with a very simple procedure. As a consequence, in 2010 we gave a linear-time algorithm to compute the DCJ-indel distance. This result allowed the inversion-indel model to be revisited from another angle. In 2013, we could show that, when the diagram that represents the relation between the two compared genomes has no bad components, the inversion-indel distance is equal to the DCJ-indel distance. In the present work we complete the study of the inversion-indel distance by giving the first algorithm to compute it exactly even in the presence of bad components. [ABSTRACT FROM AUTHOR]

A covering code is a set of codewords with the property that the union of balls, suitably defined, around these codewords covers an entire space. Generally, the goal is to find the covering code with the minimum size codebook. While most prior work on covering codes has focused on the Hamming metric, we consider the problem of designing covering codes defined in terms of either insertions or deletions. First, we provide new sphere-covering lower bounds on the minimum possible size of such codes. Then, we provide new existential upper bounds on the size of optimal covering codes for a single insertion or a single deletion that are tight up to a constant factor. Finally, we derive improved upper bounds for covering codes using R ≥ 2 insertions or deletions. We prove that codes exist with density that is only a factor O(R log R) larger than the lower bounds for all fixed R. In particular, our upper bounds have an optimal dependence on the word length, and we achieve asymptotic density matching the best known bounds for Hamming distance covering codes. [ABSTRACT FROM AUTHOR]

In order to show how research on historical epistolary language can contribute to sociolinguistics and applied linguistics, the present article examines some examples of late 18th-century letters. The research sample includes letters written to Vilnius University professors in that period (now archived in the Vilnius University Library), where the authors of the letters use code-switching or write in a language other than what we would nowadays think of as default. The cases under investigation have revealed that the use of an unusual language could be motivated by pedagogical goals, whereas code-switching could be caused, among other factors, by the need to refer to new realities or to clarify meaning; it could also be used for rhetorical expression (poetic function of language). The article is also important in that it presents accidentally detected instances of code-switching that are generally hard to identify in historically distant letters, e.g. Polish elements in French, Lithuanian and Russian elements in Polish texts. The article is intended to stimulate interest in the research on archaic manuscripts and to enrich the existing knowledge about the linguistic environment of the old Vilnius University.

Restriction site Associated DNA Sequencing (RAD-Seq) is a technique characterized by the sequencing of specific loci along the genome that is widely employed in the field of evolutionary biology since it allows to exploit variants (mainly Single Nucleotide Polymorphism—SNPs) information from entire populations at a reduced cost. Common RAD dedicated tools, such as STACKS or IPyRAD, are based on all-vs-all read alignments, which require consequent time and computing resources. We present an original method, DiscoSnp-RAD, that avoids this pitfall since variants are detected by exploiting specific parts of the assembly graph built from the reads, hence preventing all-vs-all read alignments. We tested the implementation on simulated datasets of increasing size, up to 1,000 samples, and on real RAD-Seq data from 259 specimens of Chiastocheta flies, morphologically assigned to seven species. All individuals were successfully assigned to their species using both STRUCTURE and Maximum Likelihood phylogenetic reconstruction. Moreover, identified variants succeeded to reveal a within-species genetic structure linked to the geographic distribution. Furthermore, our results show that DiscoSnp-RAD is significantly faster than state-of-the-art tools. The overall results show that DiscoSnp-RAD is suitable to identify variants from RAD-Seq data, it does not require time-consuming parameterization steps and it stands out from other tools due to its completely different principle, making it substantially faster, in particular on large datasets.

Abstract Background Glucocorticoids are commonly used in the clinical setting for their potent anti-inflammatory effects; however, significant variations in response to treatment have been demonstrated. Although the underlying mechanisms have yet to be fully understood, this variable response may be a result of alterations in human glucocorticoid receptor (hGR) expression and function. In addition to hGRα, the biologically active isoform, a screening of current databases and publications revealed five alternative splice isoforms and hundreds of variants that have been reported to date. Many of these changes in the hGR-coding gene, NR3C1, have been linked to pathophysiology. However, many studies focus on evaluating hGR expression in vitro or detecting previously reported variants. Results In this study, blood from healthy volunteers, burn and asthma patients, as well as from peripheral blood mononuclear cells isolated from leukoreduced donor whole blood, were screened for NR3C1 isoforms. We identified more than 1500 variants, including an additional 21 unique splice isoforms which contain 15 new cryptic exons. A dynamic database, named the Universal hGR (UhGR), was created to annotate and visualize the variants. Conclusion This identification of naturally occurring and stress-induced hGR isoforms, as well as the establishment of an hGR-specific database, may reveal new patterns or suggest areas of interest that will lead to the improved understanding of the human stress response system.

Deletions in the 3′ end region of the hepatitis B virus (HBV) X open reading frame (HBX) may affect the core promoter (Cp) and have been frequently associated with hepatocellular carcinoma (HCC). The aim of this study was to investigate the presence of variants with deletions and/or insertions (Indels) in this region in the quasispecies of 50 chronic hepatitis B (CHB) patients without HCC. We identified 103 different Indels in 47 (94%) patients, in a median of 3.4% of their reads (IQR, 1.3–8.4%), and 25% (IQR, 13.1–40.7%) of unique sequences identified in each quasispecies (haplotypes). Of those Indels, 101 (98.1%) caused 44 different altered stop codons, the most commonly observed were at positions 128, 129, 135, and 362 (putative position). Moreover, 39 (37.9%) Indels altered the TATA-like box (TA) sequences of Cp; the most commonly observed caused TA2 + TA3 fusion, creating a new putative canonical TATA box. Four (8%) patients developed negative clinical outcomes after a median follow-up of 9.4 (8.7–12) years. In conclusion, we observed variants with Indels in the HBX 3′ end in the vast majority of our CHB patients, some of them encoding alternative versions of HBx with potential functional roles, and/or alterations in the regulation of transcription.

In Russia and around the world, there are important questions regarding the potential threats to national and biological safety created by genetic technologies and the need to improve or introduce new, justified, and adequate measures for their control, regulation, and prevention. The article shows that a significant volume of the global market is occupied by five major transgenic crops, and producers are ready to switch to crops with an edited genome that has been approved in the United States, Argentina, and other countries. We propose a qualitatively new approach to the risk assessment of edited plants, "Safe Design," and we have also developed an extremely important, fundamentally new approach to the development of methods that combine next-generation sequencing (NGS) and Bioinformatics for the assessment of the crop import biosafety. The proposed mathematical approach provides a detailed analysis of the possible insertions of DNA fragments into the genome of edited crops and a clarification of their biological significance. The developed method can be used in the rapid screening of plants for the presence of potentially dangerous genes, viral sequences, and nonspecific promoter sequences. [ABSTRACT FROM AUTHOR]

Background: Comparative chloroplast genomics could shed light on the major evolutionary events that established plastomic diversity among closely related species. The Polypodiaceae family is one of the most species-rich and underexplored groups of extant ferns. It is generally recognized that the plastomes of Polypodiaceae are highly notable in terms of their organizational stability. Hence, no research has yet been conducted on genomic structural variation in the Polypodiaceae. Results: The complete plastome sequences of Neolepisorus fortunei, Neolepisorus ovatus, and Phymatosorus cuspidatus were determined based on next-generation sequencing. Together with published plastomes, a comparative analysis of the fine structure of Polypodiaceae plastomes was carried out. The results indicated that the plastomes of Polypodiaceae are not as conservative as previously assumed. The size of the plastomes varies greatly in the Polypodiaceae, and the large insertion fragments present in the genome could be the main factor affecting the genome length. The plastome of Selliguea yakushimensis exhibits prominent features including not only a large-scale IR expansion exceeding several kb but also a unique inversion. Furthermore, gene contents, SSRs, dispersed repeats, and mutational hotspot regions were identified in the plastomes of the Polypodiaceae. Although dispersed repeats are not abundant in the plastomes of Polypodiaceae, we found that the large insertions that occur in different species are mobile and are always adjacent to repeated hotspot regions. Conclusions: Our results reveal that the plastomes of Polypodiaceae are dynamic molecules, rather than constituting static genomes as previously thought. The dispersed repeats flanking insertion sequences contribute to the repair mechanism induced by double-strand breaks and are probably a major driver of structural evolution in the plastomes of Polypodiaceae. [ABSTRACT FROM AUTHOR]

Restriction site Associated DNA Sequencing (RAD-Seq) is a technique characterized by the sequencing of specific loci along the genome that is widely employed in the field of evolutionary biology since it allows to exploit variants (mainly Single Nucleotide Polymorphism—SNPs) information from entire populations at a reduced cost. Common RAD dedicated tools, such as STACKS or IPyRAD, are based on all-vs-all read alignments, which require consequent time and computing resources. We present an original method, DiscoSnp-RAD, that avoids this pitfall since variants are detected by exploiting specific parts of the assembly graph built from the reads, hence preventing all-vs-all read alignments. We tested the implementation on simulated datasets of increasing size, up to 1,000 samples, and on real RAD-Seq data from 259 specimens of Chiastocheta flies, morphologically assigned to seven species. All individuals were successfully assigned to their species using both STRUCTURE and Maximum Likelihood phylogenetic reconstruction. Moreover, identified variants succeeded to reveal a within-species genetic structure linked to the geographic distribution. Furthermore, our results show that DiscoSnp-RAD is significantly faster than state-of-the-art tools. The overall results show that DiscoSnp-RAD is suitable to identify variants from RAD-Seq data, it does not require time-consuming parameterization steps and it stands out from other tools due to its completely different principle, making it substantially faster, in particular on large datasets. [ABSTRACT FROM AUTHOR]

Previous studies have indicated that each conotoxin precursor has a hyperconserved signal region, a rather conserved pro region and a hypervariable mature region, and nucleotide mutations are the main driven factor. However, in this study, we made an in-depth analysis on the M-superfamily conotoxin precursors and found that the diversity of the signal, pro and mature regions are more complicated than previous findings. Different conotoxin precursors can have same signal, pro and/or mature regions, especially different conotoxin precursors with same mature region but different signal and pro regions. In addition, insertions and deletions (indels) were detected in conotoxin precursors. Indels are infrequent in the signal region but frequent in the pro and mature regions. In contrast to deletions that dominate in the pro region, insertions dominate in the mature region. The number of amino acids is crucial for the physiological functions of mature conotoxins, therefore indels, especially insertions in the mature region, play an important role in the sequence and function diversity of conotoxins. [ABSTRACT FROM AUTHOR]

• State of the art of thermographic applications to the study of bronzes. • Study of the main steps of the lost-wax casting process. • Use of passive and active thermography for the study of artistic bronzes. • Thermographic investigations of defects and repairs of artistic bronzes. • Thermographic analysis of the masterpieces of the bronze statuary of Rome. • Quantitative evaluations of the thermal properties of copper alloys. The study of bronze statues obtained by the lost-wax casting method results of particular relevance from the artistic and historical points of view. In particular, the characterization of structural and subsurface elements of bronzes is very useful to gather insight concerning their preservation state and manufacturing process. For these purposes, infrared thermography has been successfully employed to investigate different kind of items of artistic bronzes, such as repairs, defects and inserts, providing also the possibility to perform the depth-resolved study of the observed subsurface features thanks to the possibility it also provides to evaluate the thermal transport properties of the investigated materials. In this work, the experimental configurations and the capabilities of such a technique have been reviewed. The state of the art of the results obtained by infrared thermography for the analysis of artistic bronzes is presented. It is thus shown that infrared thermography can be nowadays considered as a reliable and consolidated technique to map in a non-destructive way a wide spectrum of features of bronzes. [ABSTRACT FROM AUTHOR]

Arynes and donor–acceptor (D–A) cyclopropanes are two classes of strained systems having the potential for numerous applications in organic synthesis. The last two decades have witnessed a renaissance of interest in the chemistry of these species primarily because of the mild and robust methods for their generation or activation. Commonly, arynes as easily polarizable systems result in 1,2‐disubstitution, whereas D‐A cyclopropanes as polarized systems lead to 1,3‐bisfunctionalization thereby showing striking similarities. Transformations with 1,2‐ and 1,3‐dipoles afford cyclic structures. With arynes, emerging four‐membered rings as intermediates might react further, whereas the analogous five‐membered rings obtained from D–A cyclopropanes are most often the final products. However, there are a few cases where these intermediates behave surprisingly differently. This Minireview highlights the parallels in reactivity between arynes and D–A cyclopropanes thereby shedding light on the neglected similarities of these two reactive species. [ABSTRACT FROM AUTHOR]