Loss Of Cohesion Research Articles

A Study of Strength Parameter Evolution and a Statistical Damage Constitutive Model of Cemented Sand and Gravel.

Cemented sand and gravel (CSG) has a wide range of applications in dam construction, and its properties are between rockfill and roller compacted concrete (RCC). A difference in gel content will result in a variance in CSG's structure and mechanical properties. To investigate the intricate structural mechanical properties of CSG, this study conducted a series of laboratory tests and associated discrete element analyses. Accordingly, the evolution law of the strength parameters of CSG is explored and a statistical damage constitutive model suitable for CSG is established. The main contributions of this study are as follows: (1) The failure mechanism of the CSG was described from the microscopic level, and the evolution law of the strength parameter cohesion and friction angle of the CSG was analyzed and summarized. (2) Based on the particle flow model, the energy development law and the spatiotemporal distribution law of acoustic emission (AE) provide illustrations of the strain hardening-softening transition features and the interaction between cohesion and friction of CSG. (3) The evolution function between the strength parameter and the strain softening parameter was built, and the critical strain softening parameter was determined by the microcrack evolution law of the particle flow model. (4) The accuracy of the evolution curve was confirmed by comparing it to experimental results. (5) Based on the relationship between cohesion loss and material damage, a statistical damage constitutive model was developed using the improved Mohr-Coulomb strength criterion as the micro strength function. The constitutive model can accurately describe the stress-strain curves of CSG with different gel content. Furthermore, the model reflects the strain hardening-softening properties of CSG and reveals the relationship between the weakening of cohesion and material damage at the microscopic level. These findings provide valuable guidelines for investigating the damage laws and microcosmic failure features of CSG and other relevant materials.

Central Cohesion Gradual Hashing for Remote Sensing Image Retrieval

With the recent development of remote sensing technology, large image repositories have been collected. In order to retrieve the desired images of massive remote sensing data sets effectively and efficiently, we propose a novel central cohesion gradual hashing (CCGH) mechanism for remote sensing image retrieval. Firstly, we design a deep hashing model based on ResNet-18 which has a shallow architecture and extracts features of remote sensing imagery effectively and efficiently. Then, we propose a new training model by minimizing a central cohesion loss which guarantees that remote sensing hash codes are as close to their hash code centers as possible. We also adopt a quantization loss which promotes that outputs are binary values. The combination of both loss functions produces highly discriminative hash codes. Finally, a gradual sign-like function is used to reduce quantization errors. By means of the aforementioned developments, our CCGH achieves state-of-the-art accuracy in the task of remote sensing image retrieval. Extensive experiments are conducted on two public remote sensing image data sets. The obtained results support the fact that our newly developed CCGH is competitive with other existing deep hashing methods.

Assessment of the Hot-Cracking Susceptibility of Welded Joints of the 7CrMoVTiB10-10 Bainitic Steel Used in Heat Exchangers

Bainitic steel containing approx. 2.25% Cr and 0.6 Mo with micro-additions of V, Ti, and B, designated as 7CrMoVTiB10-10 (T/P24), is one of the new construction materials used in new supercritical power units. The weldability of 7CrMoVTiB10-10 is defined as the hot-cracking susceptibility, it should be stated that the hot cracking in the welded joints of 7CrMoVTi10-10 is determined by phenomena occurring in the high-temperature brittleness range (HTBR). In this work, the HTBR is established for both the base material and welding conditions, taking into account the critical temperature-strain intensity (CST) and the critical strain speed (CSS). The HTBR for 7CrMoVTi10-10 is 122 °C wide and covers temperatures from 1394 °C to 1516 °C. Under imposed deformation conditions (typical during welding), the HTBR extends to a width of 293 °C towards lower temperatures, i.e., from 1516 °C to 1223 °C. The CSS = 0.83 1/s, the CST = 0.003 1/°C, and the Rf index = 0.12, which can be adopted as the criteria for the susceptibility of 7CrMoVTiB 10-10 to hot cracking under imposed deformation conditions. The hot cracking in 7CrMoVTiB10-10 occurs as a result of the loss of cohesion by the thin liquid layer crystallising between the growing weld crystals. Such cracks appear when the CSS or the CST is exceeded within the HTBR.

Combining discrete and continuum mechanics to investigate local wear processes induced by an abrasive particle flow

Wear caused by hard debris or abrasive slurries trapped between moving surfaces is a major industrial problem concerning engineering and agriculture machine components, causing abrasion and reducing their service life. In this context, the wear of diamond tools used to cut stones represents an interesting case study due to the particular tribological interactions involved. Diamond tools are characterised by diamonds (the cutting edge) and the metal matrix (the retaining binder). While several attempts have been made to analyse diamond wear, the wear process involving the matrix is not yet well understood. In particular, the phenomena responsible for wear at the local scale have not yet been fully investigated as they are difficult to quantify experimentally and the existing numerical models, to the authors' knowledge, greatly simplify the physical behaviour and interactions between the different materials in contact. A new code is therefore used in this work. It is able to treat the metal matrix as a deformable polycrystalline material and the debris flow by controlling the shape and size of the grains. Furthermore, the wear of the metal matrix will be described as a loss of intergranular cohesion caused by the continuous passage of debris through a cohesive contact law that also takes fatigue into account. The model will show, albeit qualitatively, that the wear of the metal surface is caused by the asperities of the debris grains, thus validating one of the fundamental assumptions behind the model defined by the same authors at a larger scale. Another aspect investigated is the relationship between the temporal evolution of wear and the roughness of the metal surface. Again, it will be shown how the temporal evolution of the metal surface is consistent with what has been observed in the literature. Moreover, due to the complexity of the model, a sensitivity study will be necessary to understand the physical significance of the parameters and how to adapt them to the specific case study. It will then be shown how these parameters can change the physics of the problem being analysed and must therefore be chosen carefully.

Sustainable asphalt mixtures by partial replacement of fine aggregates with low-grade magnesium carbonate by-product

The utilisation of large quantities of raw materials for asphalt mixtures manufacturing, such as aggregates, is an environmental issue that must be addressed. This concern has led to valorising waste and by-products as more sustainable alternative raw materials. This research is aimed at evaluating the use of a low-grade magnesium carbonate (LG-MC) by-product as a partial replacement of fine aggregates and as a filler of asphalt mixtures. A mechanical analysis has been performed studying the effect of this by-product on the moisture sensitivity, cracking resistance and cohesion loss resistance of asphalt mixtures. Cracking resistance was assessed under different temperatures (20, 5 and −5 ºC) and conditions (unconditioned and aged). Results indicated that moisture sensitivity and cohesion loss resistance of asphalt mixtures with LG-MC by-product were not affected, obtaining similar results to those of the reference mixture. A protective effect in the mixture cracking resistance was observed using LG-MC. At low temperatures or after ageing, this by-product tends to maintain ductility to a greater extent. The study indicates that LG-MC is suitable as a partial substitute for the fine fraction of aggregates, as well as for the total amount of filler in asphalt mixtures manufacturing for road pavements.

Mitotic Perturbation Is a Key Mechanism of Action of Decitabine in Myeloid Tumor Treatment

Background: Decitabine (DAC) is one of the first generation of epigenetic drugs used clinically to treat myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). Historically, DAC was considered as a cytotoxic agent when it was first developed in the 1960s. Subsequent studies in 1980s showed that DAC can induce DNMT1 degradation and DNA hypomethylation at non-cytotoxic concentration. Since then, DNA demethylation has been considered as the main mechanism of action of DAC. The DAC-induced DNA hypomethylation was shown to induce upregulation of tumor suppressor genes or endogenous retroviruses, which could contribute to the antitumor effect of DAC. Recently, DAC was also shown to be effective even in MDS and AML with TP53 mutations. However, it remains unclear why myeloid tumors, especially those with TP53 mutations, are particularly susceptible to DAC treatment. Methods: Cancer Dependency Map (DepMap) database was used to evaluate in vitro sensitivity of human cancer cell lines to DAC. To identify essential genes that regulate sensitivity of myeloid tumors to DAC, we performed a genome-wide CRISPR-dCas9 activation screen using murine MDS/AML cells expressing ASXL1 and SETBP1 mutants (cSAM cells). After transduction of mouse genome-wide CRISPRa-v2 library, cSAM cells were cultured with DMSO or DAC for 1 week. We extracted genomic DNA from the cells at the start and end of our screen and quantified the relative representation of each sgRNA. To assess the effect of DAC on mitosis, we established the time-lapse system optimized for non-adherent MDS-L-2007 cells (a human secondary AML (sAML) cell line derived from an MDS cell line, MDS-92). Results: We first explored DepMap database and found that myeloid tumors are susceptible to DAC at clinically achievable concentration, while most solid tumor cell lines are not. The CRISPR/dCas9-activation screen revealed that genes involved in chromosome segregation, including Cdk1, Cdc20, Cdca8 and Dsn1, were significantly enriched in DAC-resistant cells, indicating that overexpression of mitotic regulators conferred resistance to DAC in cSAM cells. We also found that DAC strongly induced aneuploidy and polyploidy (>4n) in myeloid tumors, especially in those with TP53 mutations and sAML cells. Furthermore, the time-lapse imaging revealed that DAC treatment prolonged the duration of metaphase and increased multipolar mitosis and abscission failure in MDS-L-2007 cells (Figure). Thus, DAC perturbs mitosis and has cytotoxic effects at low concentrations in myeloid tumors. Next, we assessed the role of DNMT1 in the DAC-induced mitotic defects in myeloid tumors. To our surprise, the DAC-induced aneuploidy and apoptosis were markedly attenuated in DNMT1-depleted myeloid tumors. In contrast, overexpression of Dnmt1 increased sensitivity of myeloid tumors to DAC. These results indicate that DAC perturbs mitosis not through DNMT1 degradation and subsequent DNA demethylation, but through DNMT1 itself in myeloid tumors. In line with this, chromatin-bound DNMT1 protein was retained even with DAC, whereas DAC induced rapid degradation of DNMT1 in the nucleoplasm fraction. Importantly, the Dnmt1-C1229A mutant, which loses the ability to induce DNMT1-DNA covalent bond formation, did not enhance the DAC-driven mitotic defects. In addition, DAC treatment increased frequency of cohesion loss between sister chromatids in MDS-L-2007 cells, as evidenced by the absence of centromere connection of sister chromatids at metaphase. Moreover, the in vitroXenopus cell-free system which reproduces replication-dependent DNA methylation maintenance revealed that addition of 5-aza-dCTP strongly promoted chromatin binding of DNMT1, while it inhibited that of cohesion complex members (SMC3 and SCC1). Taken together, these results strongly indicate that the aberrant DNMT1 retention on chromatin induced by DAC leads to cohesion loss and mitotic defects in myeloid tumors. Conclusion: These findings challenge the current assumption that DAC inhibits leukemogenesis by inducing DNA hypomethylation. Rather, the anti-leukemia effect of DAC is likely mediated mainly by the non-epigenetic mechanism: mitotic perturbation through aberrant DNMT1-DNA covalent bonds and cohesion loss of sister chromatids. Our study also suggests that DAC will be most effective on tumors with impaired mitotic fidelity, such as AML and MDS with TP53 mutations. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Glyphosate-Based Herbicide Causes Cellular Alterations to Gut Epithelium of the Neotropical Stingless Bee Melipona quadrifasciata quadrifasciata (Hymenoptera: Meliponini).

Glyphosate-based herbicides (GBH) are the best-selling pesticides in Brazil, with hundreds of thousands of tons sold per year. There is no study investigating morphological alterations caused by GBH on the epithelium of the gut in bees. Here, we aimed to demonstrate effects of chronic ingestion of GBH in the midgut digestive cells of the Brazilian stingless bee Melipona quadrifasciata quadrifasciata Lepeletier 1836. We kept forager workers of M. quadrifasciata in laboratory conditions and fed on food contaminated with three different concentrations of GBH for 10days, after which the midgut digestive cell structure and ultrastructure were analyzed. The presence of GBH in food did not affect food consumption, indicating that M. quadrifasciata bees do not reject food contaminated with GBH. As digestive cells of the midgut release apocrine secretion as a detoxication mechanism, we expected that the ingestion of food contaminated with GBH in the present study affect the height of midgut digestive cells. However, such reduction did not occur, probably because of the low-test concentrations. Although there were differences in digestive cell ultrastructure, ingestion of GBH impaired midgut digestive cell cohesion by disorganizing the smooth septate junctions between cells, which may probably be caused by the adjuvant "polyethoxylated tallow amine" present in the GBH. Previous studies demonstrated that GBH increase bees' sensibility to intestine infections, based on the present results we hypothesized that the loss of cell cohesion in the midgut epithelium favors pathogenic microbial infections and harms food absorption, increasing bees' mortality.

Metastasis of a Primary Sinonasal Alveolar Rhabdomyosarcoma to the Testicle in an Adult Patient

Abstract Introduction/Objective Alveolar rhabdomyosarcoma is an aggressive tumor of skeletal muscle differentiation that predominantly affects adolescents and young adults, and is rare over 45 years of age. It has poor prognosis with metastasis, and most commonly spreads to the lymph nodes, bone marrow, and lungs. In this report, we describe a middle-aged patient with a primary sinonasal alveolar rhabdomyosarcoma which metastasized to the right testicle, an unusual metastatic site reported only a few times in literature. Methods/Case Report Our patient is a 53 year old male who presented in 2020 with recurrent epistaxis and bilateral cervical lymphadenopathy over a 2 month period. Maxillofacial CT/MRI imaging revealed a 4-cm sized mass within the left nasal cavity eroding into the ethmoid sinuses. The patient underwent endoscopic sinus surgery of the sinonasal mass, which on histology, appeared as poorly differentiated small round blue cells with numerous mitoses infiltrating as single cells and nests. These cells stained positive for vimentin, myogenin, desmin, and CD56, and negative for AE1/AE3, chromogranin, S-100, CD99, and CD45. The cells showed very high Ki67 proliferation index (70-80%) and tested positive for FOXO1 gene rearrangement, which supported the diagnosis of alveolar rhabdomyosarcoma. The patient completed chemoradiation therapy, and MRI scans over the next 2 years were negative for residual sinonasal tumor. However, the patient returned in 2022 after having undergone a right orchiectomy at an outside hospital for testicular pain, and abdominal CT showed diffuse retroperitoneal lymphadenopathy concerning for metastasis. On histology, the resected testicle showed seminiferous tubules infiltrated and destroyed by sheets of poorly differentiated small round blue cells with fibrous septae separating the nests of tumor cells into alveolar-like spaces with central loss of cohesion. The tumor cells showed the same immunohistochemical staining pattern as the primary sinonasal lesion, thus confirming it to be metastatic alveolar rhabdomyosarcoma. Results (if a Case Study enter NA) NA. Conclusion It is unusual for alveolar rhabdomyosarcomas to occur in adults over 45 years old, and is even rarer for these tumors to metastasize to the testicle. Metastases also only account for 1% of testicular tumors. Our report documents a very rare case of an alveolar rhabdomyosarcoma in a middle-aged adult which metastasized to the testicle after chemoradiation therapy.

Pathogenic variants in SLF2 and SMC5 cause segmented chromosomes and mosaic variegated hyperploidy

Embryonic development is dictated by tight regulation of DNA replication, cell division and differentiation. Mutations in DNA repair and replication genes disrupt this equilibrium, giving rise to neurodevelopmental disease characterized by microcephaly, short stature and chromosomal breakage. Here, we identify biallelic variants in two components of the RAD18-SLF1/2-SMC5/6 genome stability pathway, SLF2 and SMC5, in 11 patients with microcephaly, short stature, cardiac abnormalities and anemia. Patient-derived cells exhibit a unique chromosomal instability phenotype consisting of segmented and dicentric chromosomes with mosaic variegated hyperploidy. To signify the importance of these segmented chromosomes, we have named this disorder Atelís (meaning - incomplete) Syndrome. Analysis of Atelís Syndrome cells reveals elevated levels of replication stress, partly due to a reduced ability to replicate through G-quadruplex DNA structures, and also loss of sister chromatid cohesion. Together, these data strengthen the functional link between SLF2 and the SMC5/6 complex, highlighting a distinct role for this pathway in maintaining genome stability.

Experimental Comparison of Efficiency of Water-Soluble and Solvent Hydrophobic Agents for Concrete

The paper presents the results and assessment of the properties and capabilities of new types of surface hydrophobic agents for the treatment of fresh and matured surfaces of concrete and other cement-bound layers. Hydrophobisation prevents the premature evaporation of water and thus plastic shrinkage, which inevitably leads to the formation of cracks in cement-based structures. The influence of the new type of hydrophobic agents, epoxy water-based (EWH) and acrylate (AH) containing solvent, on the physical and mechanical properties of the treated concrete samples was assessed, including the adhesion of hydrophobisation on the concrete surface layers. It was confirmed that surface hydrophobisation successfully prevents premature evaporation of water, and thus, plastic shrinkage (concrete treated with EWH_0.3 showed more than two times lower shrinkage than reference concrete). The concrete samples treated by hydrophobisation agents showed higher strength after 120 days (37.5 MPa) in comparison with untreated concrete (32.8 MPa). Different properties were recorded with different types of hydrophobisation agents, including compressive strength after 90 days (31.2 MPa with EWH_0.15, and 35.9 MPa with AH_0.15). Water absorption after 120 days was lowest with EWH_0.3 samples (3.77%), two times lower than AH_0.15 (6.98%). The layer of hydrophobisation agent EWH_0.3 was thicker than AH_0.15, leading to lower water absorption of treated concrete and higher resistance to defrosting chemicals—waste 8.5. g/m2 with EWH_0.3 in comparison to 35.7 g/m2 with AH_0.15. Furthermore, a difference in the hydrophobisation behaviour was shown with blocking of infiltration from the chemically aggressive environment into the concrete substrate. Deterioration of the surface concrete exposed to 10% HCl solution was worse with AH_0.15; but the concrete surface treated with AH_0.15 showed better resistance than the EWH treated surface, when exposed to 5% CH3COOH. Degradation of the hydrophobisation integrity and the loss of cohesion between the concrete and the surface treatment after exposure to acetic acid and hydrochloric acid was observed using scanning electron microscopy (SEM).

Stripping propensity detection of HMA Mixes: With focus on image processing method

• The incorporation of anti- Stripping in hot mix asphalt was investigated. • The effects of anti- Stripping agents on the specimens by image processing were evaluated. • The performance of specimens under different working conditions was analyzed. • Anti-stripping agent improved of adhesive property of HMA asphalt mixtures. Infiltration of water into Hot Mix Asphalt (HMA) can cause performance degradation and service life reduction of the asphalt concrete pavements. Moreover, it can lead to adhesion failure at the binder-aggregate interface and/or cohesion failure within the binder or binder-filler mastic. In this paper, three aggregate types, three anti-stripping additives, and one bitumen type were selected to study this phenomenon. Based on the results of chemical analysis, selected aggregates were categorized into two groups: non-stripping and stripping aggregates. Then, the stripping propensity of loose and compacted mixes was assessed through boiling water, retained compressive strength, and indirect tensile tests. The chemical analysis was showed the importance of amphoteric and alkaline oxides in moisture sensitivity in silicate rocks. The results emphasize the detrimental effect of moisture in HMA mixes even in the non-stripping mix. All selected anti-stripping additives improve the tensile strength ratio (TSR) of specimens, however, the stripping propensity of some treated mixes was maintained. In the next step, cohesion loss and adhesion loss surfaces of loose mixes and ITS specimens was determined under the wet conditions by the image processing technique in ENVI and MATLAB software packages. Based on image processing results, the higher retained bitumen coating in loose mixes leads to less stripping propensity of compacted specimens and the tensile strength ratio of modified Lottman specimens is decreased by an increase in the percentage of broken aggregates and adhesion loss. Image processing data were subjected to nonlinear regression and multiple analysis of variance (MANOVA) to investigate this phenomenon.

An Appraisal of Models for Roads Pavement Failures in Ebonyi State Nigeria

Nigeria road pavement is subjected to have low road density of 23km/m2 of the pave land area and justification for this material stress, functional disability and loss of cohesion. In Ebonyi state there is needs to assess the impact of failed road pavement on economic growth and social stability of the state. Most of the state urban roads failed because of many vehicles passing in definite section of the road per unit time at any suitable period, subjecting the paved areas into physically disintegration of crystalline aggregated material informed of ruttings, pothole, raveling and cracks and some deteriorate or decomposed in a large number of cement aggregate into organic matter causing chemical separations and moisture attack on the paved area by attacking the fabric bond of the binding pavement. The aim of this research is to analyze roads pavement failures for effective cost management. The research design comprised extensive literature. This research was to facilitate the measurement of variables on affected areas causing surface depression and surface deterioration on large number of aggregated crystalline material from rehabilitation of the respective road projects. The research was design to measure stress types, stress values, stress seventy and stress density derive from affected paved area. The data collected were presented in tables, percentage, and pie chart and analyzed with multiple regressions. The findings will establish the state of stress over strain will be sustainable for road pavement in urban areas. The model implies based on the data collected the cause of stress values in urban roads increase by 0.284 (28.4%) were trigger increase in road rehabilitation, repairs and remedial works by 0.77, 0.31 and 0.60 and which were ascertain the level of cost implementation for effective life cycle costing on urban roads in the state.

Cholinergic signaling impairs cardiomyocyte cohesion.

Cardiac autonomic nervous system (ANS) dysregulation is a hallmark of several cardiovascular diseases. Adrenergic signaling enhanced cardiomyocyte cohesion via PKA-mediated plakoglobin phosphorylation at serine 665, referred to as positive adhesiotropy. This study investigated cholinergic regulation of cardiomyocyte cohesion using muscarinic receptor agonist carbachol (CCH). Dissociation assays, Western blot analysis, immunostaining, atomic force microscopy (AFM), immunoprecipitation, transmission electron microscopy (TEM), triton assays, and siRNA knockdown of genes were performed in either HL-1 cells or plakoglobin (PG) wild type (Jup+/+ ) and knockout (Jup-/- ) mice, which served as a model for arrhythmogenic cardiomyopathy. In HL-1 cells grown in norepinephrine (NE)-containing medium for baseline adrenergic stimulation, and murine cardiac slice cultures from Jup+/+ and Jup-/- mice CCH treatment impaired cardiomyocyte cohesion. Immunostainings and AFM experiments revealed that CCH reduced desmoglein 2 (DSG2) localization and binding at cell borders. Furthermore, CCH reduced intercalated disc plaque thickness in both Jup+/+ and Jup-/- mice, evidenced by TEM analysis. Immunoprecipitation experiments in HL-1 cells revealed no changes in DSG2 interaction with desmoplakin (DP), plakophilin 2 (PKP2), PG, and desmin (DES) after CCH treatment. However, knockdown of any of the above proteins abolished CCH-mediated loss of cardiomyocyte cohesion. Furthermore, in HL-1 cells, CCH inhibited adrenergic-stimulated ERK phosphorylation but not PG phosphorylation at serine 665. In addition, CCH activated the AKT/GSK-3β axis in the presence of NE. Our results demonstrate that cholinergic signaling antagonizes the positive effect of adrenergic signaling on cardiomyocyte cohesion and thus causes negative adhesiotropy independent of PG phosphorylation.

Prediction of malignant transformation and recurrence of oral epithelial dysplasia using architectural and cytological feature specific prognostic models

AbstractOral epithelial dysplasia (OED) is a precursor state usually preceding oral squamous cell carcinoma (OSCC). Histological grading is the current gold standard for OED prognostication but is subjective and variable with unreliable outcome prediction. We explore if individual OED histological features can be used to develop and evaluate prognostic models for malignant transformation and recurrence prediction. Digitised tissue slides for a cohort of 109 OED cases were reviewed by three expert pathologists, where the prevalence and agreement of architectural and cytological histological features was assessed and association with clinical outcomes analysed using Cox proportional hazards regression and Kaplan–Meier curves. Within the cohort, the most prevalent features were basal cell hyperplasia (72%) and irregular surface keratin (60%), and least common were verrucous surface (26%), loss of epithelial cohesion (30%), lymphocytic band and dyskeratosis (34%). Several features were significant for transformation (p < 0.036) and recurrence (p < 0.015) including bulbous rete pegs, hyperchromatism, loss of epithelial cohesion, loss of stratification, suprabasal mitoses and nuclear pleomorphism. This led us to propose two prognostic scoring systems including a ‘6-point model' using the six features showing a greater statistical association with transformation and recurrence (bulbous rete pegs, hyperchromatism, loss of epithelial cohesion, loss of stratification, suprabasal mitoses, nuclear pleomorphism) and a ‘two-point model' using the two features with highest inter-pathologist agreement (loss of epithelial cohesion and bulbous rete pegs). Both the ‘six point' and ‘two point' models showed good predictive ability (AUROC ≥ 0.774 for transformation and 0.726 for recurrence) with further improvement when age, gender and histological grade were added. These results demonstrate a correlation between individual OED histological features and prognosis for the first time. The proposed models have the potential to simplify OED grading and aid patient management. Validation on larger multicentre cohorts with prospective analysis is needed to establish their usefulness in clinical practice.

Aristolochic acid I exposure decreases oocyte quality.

Oocyte quality is a determinant of a successful pregnancy. The final step of oocyte development is oocyte maturation, which is susceptible to environmental exposures. Aristolochic acids (AAs), widely existing in Aristolochia and Asarum plants that have been used in traditional medicine, can result in a smaller ovary and fewer superovulated oocytes after in vivo exposure to mice. However, whether AAs affect oocyte maturation and the underlying mechanism(s) are unclear. In this study, we focused on the effect of Aristolochic acid I (AAI), a major compound of AAs, on the maturation of in vitro cultured mouse oocytes. We showed that AAI exposure significantly decreased oocyte quality, including elevated aneuploidy, accompanied by aberrant chiasma patterns and spindle organization, and decreased first polar body extrusion and fertilization capability. Moreover, embryo development potential was also dramatically decreased. Further analyses revealed that AAI exposure significantly decreased mitochondrial membrane potential and ATP synthesis and increased the level of reactive oxygen species (ROS), implying impaired mitochondrial function. Insufficient ATP supply can cause aberrant spindle assembly and excessive ROS can cause premature loss of sister chromatid cohesion and thus alterations in chiasma patterns. Both aberrant spindles and changed chiasma patterns can contribute to chromosome misalignment and thus aneuploidy. Therefore, AAI exposure decreases oocyte quality probably via impairing mitochondrial function.

Posture, gait and self-disorders: An empirical study in individuals with schizophrenia.

In schizophrenia, subjectively perceived disruptions of the sense of the Self (also referred to as "self-disorders") seem to be intimately associated with a perturbation of the implicit awareness of one's own body. Indeed, an early impairment of the motor system, including posture and gait, is now considered a marker of schizophrenia neurodevelopmental substrate and appears more pronounced in early-onset schizophrenia. Therefore, the present study was aimed at: (1) investigating a possible relationship between self-disorders, symptom dimensions and postural and gait profile in schizophrenia; (2) identifying a specific motor profile in early-onset conditions. A total of 43 schizophrenia outpatients and 38 healthy controls underwent an exhaustive investigation of posture and gait pattern. The positive and negative syndrome scale (PANSS), the examination of anomalous self experience scale (EASE) and the abnormal involuntary movement scale (AIMS) were administered to the schizophrenia group. Subsequently, schizophrenia patients were divided into early and adult-onset subgroups and compared with respect to their motor profile. We found an association between specific postural patterns (impaired sway area), a general disruption of the gait cycle and subjective bodily experiences (concerning the loss of bodily integrity, cohesion and demarcation). Only motor parameters (increased sway area and gait cadence reduction) differentiated between early and adult-onset patients. The results of the present study hint at a link between motor impairment and self-disturbances in schizophrenia and candidate a specific motor profile as a possible marker of early-onset forms.

Viscoelastic Measurements of Clay Suspensions and their Relationship to Strength of Unfired Clay Bricks with Almond Husk Additive

Engineered unfired clay bricks are an ecological alternative to overcome conventional construction materials’ inconvenience. This work investigates the rheological behavior of organo-silica suspensions, made from almond husk waste and illite clay, in relation to the compressive strength of unfired clay bricks incorporating the same waste. Selected proportions by weight of almond husk are 2, 5, 10, and 20 wt.%. Results from the compressive strength test show an improvement, of 8.98% in bricks with 2 wt.% waste content compared to the control sample, thanks to an increase in friction and the fiber bridging mechanism. Then, a progressively decrease in strength is recorded with the addition of waste. The decrease in strength is reported to be the creation of pores in the matrix, and loss of cohesion. It is found that the storage modulus, on a logarithmic scale, follows inversely the same trend of the compressive strength in previously prepared bricks. The results from the strength test and rheological test are linearly correlated. Strong coefficients of determination are found; R2=0.9809 (with 40 wt.% water content) and R2=0.9206 (with 50 wt.% water content). The findings from this study demonstrate the possibility of assessment and prediction of unfired bricks’ strength using rheometry.

Publisher's Note: "Ultrafast bandgap narrowing and cohesion loss of photoexcited fused silica" [J. Chem. Phys. 156, 224301 (2022)

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Riparian Groundwater Level Variation and Its Impacts on Bank Erosion in the Middle Yangtze River

AbstractThe interaction between groundwater flow and river flow plays an important role in the bank erosion process, but field measurements on riparian groundwater flows remain very limited, especially in large river systems. Three monitoring wells of groundwater flow were constructed at two typical sites of the Middle Yangtze River (MYR) in 2021, with the hydrographs of the riparian groundwater level and river stage being obtained. Results indicated that (a) the variation in the groundwater level generally followed with the river stage during the flood peak period, but decoupled from the river stage during the recession period; (b) the delayed response of the groundwater level to river stage variation was quantified by the ratio of their change rates, which linearly increased with the magnitude of the river stage, but decreased with the change rate of the river stage as a loose power function; and (c) the increasing ground water level resulted in a 61% loss of the cohesion of upper cohesive bank soil and a complete loss of the apparent cohesion of the lower noncohesive bank soil. The major mechanism underlying the influences of the groundwater flow on bank erosion in the MYR is probably the development of pore water pressure that changes the forces acting on soil block and reduces the soil shear strength, whereas seepage erosion is seemingly not intensive. The current study can provide a direct evidence for the response of the riparian groundwater level variation to the river stage change in a large river system.

O-162 Emerging mechanisms of oocyte genome integrity

Abstract Ageing is accompanied by aneuploidy in mammalian eggs, which underlies common pregnancy failures in reproductively older females. This is consistent with gradual, ageing-related depletion of centromeric cohesion proteins leading to premature separation of sister chromatids. However, such progressive cohesion loss does not satisfactorily explain the sharp rise in egg aneuploidy near the end of female reproductive life. Here we show that F-actin helps to keep most sister chromatids together after centromeric cohesion has deteriorated in ageing mammalian eggs. By combining targeted protein degradation with advanced microscopy of chromosomal dynamics in eggs of young and aged females, we demonstrate that actin mitigates premature sister chromatid separation arising from centromeric cohesion loss by limiting microtubule-dependent chromatid disengagement. We propose that impairment of this function underlies ageing-related exponential rise in egg aneuploidy.