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The process of cable bolt anchoring the roof of a coal mine roadway involves the mixture of different types of resin cartridges. However, this procedure presently faces several shortcomings including insufficient cartridge breakage, non-ideal viscosity and annular thickness values of the anchoring body, short effective anchorage length, incomplete hole walls in the surrounding rock, the resin cartridges easily roll, bend, overlap, and pile up on the hole wall and do not properly react. This study presents a systematic analysis of the anchoring characteristics of roof cable bolts in a roadway with weak interlayers based on the research and development of synergistic components. The synergistic mechanism is identified. Numerical simulations are performed to demonstrate the dynamic flow field characteristics of the resin cartridge mixing, and laboratory tests are performed for comparison to determine a reasonable setting for the synergistic components. Field tests are conducted to comprehensively verify the working performance of the synergistic technology. The results show that the synergistic component can greatly improve the fluidity and uniformity of the resin cartridge reaction. The anchoring performance of the synergistic anchorage cable bolt used in the field is also significantly greater than that of ordinary anchoring cable bolts and higher than or equal to the engineering requirements. When an anchor hole is broken or collapses, the spacing of the synergistic components can be reasonably adjusted (i.e., by shortening the anchorage length) to allow the resin cartridge to evenly and densely fill the anchoring area, which greatly improves the anchoring system’s bearing capacity.HighlightsCable bolt resin anchoring on roadway roofs with weak interlayers is analyzed under typical on-field construction conditions.Anchoring synergistic components greatly improve the bearing capacity and energy absorption capacity of an anchoring system.On-field dynamic mixing guidance parameters are proposed for different types of resin cartridges in combination or used alone.Synergistic component spacing adjustments effectively improve the density and uniformity of an anchoring body, thus improving the anchoring quality.

Anchor quality is a critical factor influencing the anchoring performance after drilling and expanding anchor holes. Anchoring at the bottom of the hole is an effective technical measure to improve the anchoring quality of mudstone cemented soft rock tunnels. Through a comprehensive research approach including theoretical analysis, laboratory experiments, and numerical simulation, we conducted anchoring quality tests on a self-developed bottom-hole single-wing inverted wedge-shaped hole-expanding device. The anchoring quality under different hole-expanding parameters was analyzed to reveal the anchoring enhancement mechanism at the bottom of the anchor hole. We established an anchoring model for bottom-hole hole-expanding anchoring and derived the formula for the axial force on the anchor rod during hole-expanding anchoring. The experimental results show that when the anchoring agent is K2335 resin anchoring agent, the hole-expanding length is 100 mm, the hole-expanding diameter is 58 mm, and the inverted wedge angle is 9°, the anchoring effect is optimal with a solidification rate of 92.9%. Even after the anchor rod slips and loses anchor, it still maintains a high anchoring force. On-site application results indicate that inverted wedge-shaped hole-expanding anchoring can effectively increase the anchor rod support strength, reduce tunnel deformation, and ensure the stability of coal mine tunnels. This method has significant guiding significance for solving the anchor rod support of mudstone cemented soft rock tunnels.

Observing the structure and regeneration of the myelin sheath in peripheral nerves following injury and during repair would help in understanding the pathogenesis and treatment of neurological diseases caused by an abnormal myelin sheath. In the present study, transmission electron microscopy, immunofluorescence staining, and transcriptome analyses were used to investigate the structure and regeneration of the myelin sheath after end-to-end anastomosis, autologous nerve transplantation, and nerve tube transplantation in a rat model of sciatic nerve injury, with normal optic nerve, oculomotor nerve, sciatic nerve, and Schwann cells used as controls. The results suggested that the double-bilayer was the structural unit that constituted the myelin sheath. The major feature during regeneration was the compaction of themyelin sheath, wherein the distance between the 2 layers of cell membrane in the double-bilayer became shorter and the adjacent double-bilayers tightly closed together and formed the major dense line. The expression level of myelin basic protein was positively correlated with the formation of the major dense line, and the compacted myelin sheath could not be formed without the anchoring of the lipophilin particles to the myelin sheath.

A-kinase anchoring proteins (AKAPs) shape second-messenger signaling responses by constraining protein kinase A (PKA) at precise intracellular locations. A defining feature of AKAPs is a helical region that binds to regulatory subunits (RII) of PKA. Mining patient-derived databases has identified 42 nonsynonymous SNPs in the PKA-anchoring helices of five AKAPs. Solid-phase RII binding assays confirmed that 21 of these amino acid substitutions disrupt PKA anchoring. The most deleterious side-chain modifications are situated toward C-termini of AKAP helices. More extensive analysis was conducted on a valine-to-methionine variant in the PKA-anchoring helix of AKAP18. Molecular modeling indicates that additional density provided by methionine at position 282 in the AKAP18γ isoform deflects the pitch of the helical anchoring surface outward by 6.6°. Fluorescence polarization measurements show that this subtle topological change reduces RII-binding affinity 8.8-fold and impairs cAMP responsive potentiation of L-type Ca2+ currents in situ. Live-cell imaging of AKAP18γ V282M-GFP adducts led to the unexpected discovery that loss of PKA anchoring promotes nuclear accumulation of this polymorphic variant. Targeting proceeds via a mechanism whereby association with the PKA holoenzyme masks a polybasic nuclear localization signal on the anchoring protein. This led to the discovery of AKAP18ε: an exclusively nuclear isoform that lacks a PKA-anchoring helix. Enzyme-mediated proximity-proteomics reveal that compartment-selective variants of AKAP18 associate with distinct binding partners. Thus, naturally occurring PKA-anchoring-defective AKAP variants not only perturb dissemination of local second-messenger responses, but also may influence the intracellular distribution of certain AKAP18 isoforms.

This paper adds to the growing body of literature investigating Ukrainian women refugees’ framing of their experience as forced migrants. Using semi-structured interviews with 11 Ukrainian women refugees currently residing in Romania, we explore how these women navigate the complexities of adaptation and integration in Romania. We examine their perception of refugee status, negotiation of belonging to various transnational social spaces and problematization of their lived experiences as women, mothers and main decision-makers of their families. We are equally interested in identifying the factors that empower them to rebuild their lives and foster resilience in the host country. Our analysis shows that resilient adaptation is the result of an accumulation of everyday problem-solving, professional achievement and anchoring in re-invented roles as caregivers and advocates for Ukrainian communities.

Werner syndrome (WS) is a premature aging disorder caused by WRN protein deficiency. Here, we report on the generation of a human WS model in human embryonic stem cells (ESCs). Differentiation of WRN-null ESCs to mesenchymal stem cells (MSCs) recapitulates features of premature cellular aging, a global loss of H3K9me3, and changes in heterochromatin architecture. We show that WRN associates with heterochromatin proteins SUV39H1 and HP1α and nuclear lamina–heterochromatin anchoring protein LAP2β. Targeted knock-in of catalytically inactive SUV39H1 in wild-type MSCs recapitulates accelerated cellular senescence, resembling WRN-deficient MSCs. Moreover, decrease in WRN and heterochromatin marks are detected in MSCs from older individuals. Our observations uncover a role for WRN in maintaining heterochromatin stability and highlight heterochromatin disorganization as a potential determinant of human aging.

Genomic regions preferentially associate with regions of similar transcriptional activity, partitioning genomes into active and inactive compartments within the nucleus. Herewe explore mechanisms controlling genome compartment organization in Caenorhabditis elegans and investigate roles for compartments in regulating gene expression. Distal arms of C. elegans chromosomes, which are enriched for heterochromatic histone modifications H3K9me1/me2/me3, interact with each other both in cis and in trans, while interacting less frequently with central regions, leading to genome compartmentalization. Arms are anchored to the nuclear periphery via the nuclear envelope protein CEC-4, which binds to H3K9me. By performing genome-wide chromosome conformation capture experiments (Hi-C), we showed that eliminating H3K9me1/me2/me3 through mutations in the methyltransferase genes met-2 and set-25 significantly impaired formation of inactive Arm and active Center compartments. cec-4 mutations also impaired compartmentalization, but to a lesser extent. We found that H3K9me promotes compartmentalization through two distinct mechanisms: Perinuclear anchoring of chromosome arms via CEC-4 to promote their cis association, and an anchoring-independent mechanism that compacts individual chromosome arms. In both met-2 set-25 and cec-4 mutants, no dramatic changes in gene expression were found for genes that switched compartments or for genes that remained in their original compartment, suggesting that compartment strength does not dictate gene-expression levels. Furthermore, H3K9me, but not perinuclear anchoring, also contributes to formation of another prominent feature of chromosome organization, megabase-scale topologically associating domains on X established by the dosage compensation condensin complex. Our results demonstrate that H3K9me plays crucial roles in regulating genome organization at multiple levels.

Stacking solar cells with decreasing band gaps to form tandems presents the possibility of overcoming the single-junction Shockley-Queisser limit in photovoltaics. The rapid development of solution-processed perovskites has brought perovskite single-junction efficiencies >20%. However, this process has yet to enable monolithic integration with industry-relevant textured crystalline silicon solar cells. We report tandems that combine solution-processed micrometer-thick perovskite top cells with fully textured silicon heterojunction bottom cells. To overcome the charge-collection challenges in micrometer-thick perovskites, we enhanced threefold the depletion width at the bases of silicon pyramids. Moreover, by anchoring a self-limiting passivant (1-butanethiol) on the perovskite surfaces, we enhanced the diffusion length and further suppressed phase segregation. These combined enhancements enabled an independently certified power conversion efficiency of 25.7% for perovskite-silicon tandem solar cells. These devices exhibited negligible performance loss after a 400-hour thermal stability test at 85°C and also after 400 hours undermaximumpower point tracking at 40°C.

Myocardial stress and injury invariably promote remodeling of the cardiac tissue, which is associated with cardiomyocyte death and development of fibrosis. The fibrotic process is initially triggered by the differentiation of resident cardiac fibroblasts into myofibroblasts. These activated fibroblasts display increased proliferative capacity and secrete large amounts of extracellular matrix. Uncontrolled myofibroblast activation can thus promote heart stiffness, cardiac dysfunction, arrhythmias, and progression to heart failure. Despite the well-established role of myofibroblasts in mediating cardiac disease, our current knowledge on how signaling pathways promoting fibrosis are regulated and coordinated in this cell type is largely incomplete. In this respect, cyclic adenosine monophosphate (cAMP) signaling acts as a major modulator of fibrotic responses activated in fibroblasts of injured or stressed hearts. In particular, accumulating evidence now suggests that upstream cAMP modulators including G protein-coupled receptors, adenylyl cyclases (ACs), and phosphodiesterases (PDEs); downstream cAMP effectors such as protein kinase A (PKA) and the guanine nucleotide exchange factor Epac; and cAMP signaling organizers such as A-kinase anchoring proteins (AKAPs) modulate a variety of fundamental cellular processes involved in myocardial fibrosis including myofibroblast differentiation, proliferation, collagen secretion, and invasiveness. The current review will discuss recent advances highlighting the role of cAMP and AKAP-mediated signaling in regulating pathophysiological responses controlling cardiac fibrosis.

A liquid crystal (LC) director distribution was numerically analyzed in 90-degree twisted nematic (TN) LC cells with a symmetric and an asymmetric azimuthal anchoring strength of the alignment substrate and the influence of anchoring strength on the electro-optical property of the TN cell was evaluated. The twist angle decreased with decreasing azimuthal anchoring strength and the LC orientation changed to a homogeneous orientation with the twist angle of 0 degrees in the LC cell with asymmetric azimuthal anchoring strength, specifically with the strong anchoring substrate and the weak anchoring substrate below a critical strength. The asymmetric anchoring LC cell was fabricated by using a poly (vinyl cinnamate) alignment substrate as the weak anchoring surface and a polyimide alignment substrate as the strong anchoring surface. The LC cell performed the dark–bright–dark switching of the transmittance in the crossed polarizers, since the homogeneous LC orientation changed to the TN orientation again with increasing the applied voltage. Therefore, it was experimentally confirmed that LC molecules rotated at 90 degrees in the plane on the alignment surface by the electric field perpendicular to the weak anchoring substrate.