The interplay of 3D genome organization with UV-induced DNA damage and repair.

The 3D organization of the eukaryotic genome is crucial for various cellular processes such as gene expression and epigenetic regulation, as well as for maintaining genome integrity. However, the interplay between UV-induced DNA damage and repair with the 3D structure of the genome is not well understood. Here, we used state-of-the-art Hi-C, Damage-seq, and XR-seq datasets and in silico simulations to investigate the synergistic effects of UV damage and 3D genome organization. Our findings demonstrate that the peripheral 3D organization of the genome shields the central regions of genomic DNA from UV-induced damage. Additionally, we observed that potential damage sites of pyrimidine-pyrimidone (6-4) photoproducts are more prevalent in the nucleus center, possibly indicating an evolutionary pressure against those sites at the periphery. Interestingly, we found no correlation between repair efficiency and 3D structure after 12 min of irradiation, suggesting that UV radiation alters the genome's 3D organization in a short period of time. Interestingly, however, 2 h after UV induction, we observed more efficient repair levels in the center of the nucleus relative to the periphery. These results have implications for understanding the etiology of cancer and other diseases, as the interplay between UV radiation and the 3D genome may play a role in the development of genetic mutations and genomic instability.

A Versatile Redox-Active Electrolyte for Solid Fixation of Polyiodide and Dendrite-Free Operation in Sustainable Aqueous Zinc-Iodine Batteries.

Practical utilization of zinc-iodine (Zn-I2) batteries is hindered by significant challenges, primarily stemming from the polyiodide shuttle effect on the cathode and dendrite growth on the anode. Herein, a feasible redox-active electrolyte has been introduced with tetraethylammonium iodide as an additive that simultaneously addresses the above mentioned challenges via polyiodide solidification on the cathode and the electrostatic shielding effect on the anode. The tetraethylammonium (TEA+) captures water-soluble polyiodide intermediates (I3 -, I5 -), forming a solid complex at the cathode, thereby suppressing capacity loss during charge/discharge. Furthermore, the TEA+ mitigates dendrite growth on the Zn anode via the electrostatic shielding effect, promoting uniform and compact Zn deposition at the anode. Consequently, the Zn||Zn symmetric cell demonstrates superior cycling stability during Zn plating/stripping over 4,200 h at 1 mA cm-2 and 1 mAh cm-2. The Zn||NiNC full-cell exhibits a stable capacity retention of 98.4% after 20 000 cycles (>5 months) with near-unity Coulombic efficiency at 1 A g-1. The study provides novel insights for establishing a new direction for low-cost, sustainable, and long-lifespan Zn-I2 batteries.

The chronically ill in the labour market - are they hierarchically sorted by education?

BACKGROUND: The chronically ill as a group has on average lower probability of employment compared to the general population, a situation that has persisted over time in many countries. Previous studies have shown that the prevalence of chronic diseases is higher among those with lower levels of education. We aim to quantify the double burden of low education and chronic illness comparing the differential probabilities of employment between the chronically ill with lower, medium, and high levels of education and how their employment rates develop over time. METHODS: Using merged Norwegian administrative data over a 11-year period (2008-2018), our estimations are based on multivariable regression with labour market and time fixed effects. To reduce bias due to patients' heterogeneity, we included a series of covariates that may influence the association between labour market participation and level of education. To explicitly explore the 'shielding effect' of education over time, the models include the interaction effects between chronic illness and level of education and year. RESULTS: The employment probabilities are highest for the high educated and lowest for chronically ill individuals with lower education, as expected. The differences between educational groups are changing over time, though, driven by a revealing development among the lower-educated chronically ill. That group has a significant reduction in employment probabilities both in absolute terms and relative to the other groups. The mean predicted employment probabilities for the high educated chronic patient is not changing over time indicating that the high educated as a group is able to maintain labour market participation over time. Additionally, we find remarkable differences in employment probabilities depending on diagnoses. CONCLUSION: For the chronically ill as a group, a high level of education seems to "shield" against labour market consequences. The magnitude of the shielding effect is increasing over time leaving chronically ill individuals with lower education behind. However, the shielding effect varies in size between types of chronic diseases. While musculoskeletal, cardiovascular and partly cancer patients are "sorted" hierarchically according to level of education, diabetes, respiratory and mental patients are not.

Research on Residual-Current Measurement System of Substation Considering Magnetic Shielding Effect.

Residual current is an important monitoring quantity of a power system, and a current sensor plays an important role in detecting current. The substation environment is complex. In addition to the power frequency signal, residual current also has AC and DC components. But it is also affected by the stray magnetic field of the substation. Therefore, the accuracy of the current sensor demands higher requirements. The tunnel magnetoresistive sensor has the advantages of a stable operation, high efficiency, and energy saving, but it is easily affected by the external stray magnetic field during measurements, resulting in a large error. Therefore, this paper proposes a residual-current sensing monitoring system considering the magnetic shielding effect. The root mean square error of the magnetic shielding structure is only 0.572 mA, which can effectively reduce the influence of the external magnetic field and improve the detection accuracy. At the same time, the DC measurement error is less than 1%, the AC measurement error is less than 5%, and the hybrid AC/DC error is less than 8%. It has good response ability and can accurately detect residual current.

Organic Materials with Ultrabright Phosphorescence at Room Temperature under Physiological Conditions for Bioimaging.

In contrast to the high efficiency of room temperature phosphorescence in crystal states, the generally utilized nanoparticles of organic materials in bioimaging demonstrated sharply decreased performance by orders of magnitude under physiological conditions, badly limiting the realization of their unique advantages. This case, especially for organic red/near-infrared (NIR) phosphorescence materials, is not only the challenge present in reality but more importantly, for the theoretical problem of deeply understanding and avoiding the quenching effect by oxygen and water toward excited triplet states. Herein, thanks to the intelligent molecular design by the introduction of abundant hydrophobic chains and highly-branched structures, bright and persistent red/NIR phosphorescence under physiological conditions has been realized, which demonstrated the shielding effect towards oxygen, and strengthened the intermolecular interactions to suppress the non-radiative transitions. Accordingly, the record phosphorescence intensity of nanoparticles in bioimage, up to 8.21 ± 0.36 × 108 p s-1 cm-2 sr-1, was achieved, to realize the clear phosphorescence imaging of liver and tumors in living mice, even lymph nodes in rabbit models with high SBRs. This work afforded an efficient way to achieve the bright red/NIR phosphorescence nanoparticles, guiding their further applications in biology and medicine.

Hydrogen Bond Shielding Effect for High-Performance Aqueous Zinc Ion Batteries.

Manganese oxides are highly desirable for the cathode of rechargeable aqueous zinc ion batteries (AZIBs) owing to their low cost and high abundance. However, the terrible structure stability of manganese oxide limits its practical application. Here, it is demonstrated that the hydrogen-bond shielding effect can improve the electrochemical performance of manganese oxide. Briefly, (NH4 )0.125 MnO2 (NHMO) is prepared by introducing NH4 + into the tunnel structure of α-MnO2 . The robust hydrogen bonds between N-H and host O atoms can stabilize the lattice structure of α-MnO2 and suppress the dissolution of Mn element. More importantly, it can also accelerate ions mobility kinetics by weakening the electrostatic interaction of host O atoms. Thus, the fabricated Zn||NHMO battery possesses impressive cycling life (99.5% of capacity retention over 10 000 cycles) and rate capability (109 mA h g-1 of discharge capacity at 6000 mA g-1 ). Comprehensive analyses reveal the essences of interfacial charge and bulk ions transfer. This finding opens new opportunities for the development of high-performance AZIBs.

Shielding effect of a lead apron on the peripheral radiation dose outside the applicator of electron beams from an Elekta linear accelerator.

PURPOSE: To evaluate the shielding effect of lead aprons (LAs) on peripheral radiation doses outside the applicator of electron beams from a linear accelerator. METHODS: Out-of-field radiation doses of 4-, 6-, 8-, 10-, 12-, and 15-MeV electron beams from an Elekta Synergy linear accelerator (linac) were measured by thermoluminescence dosimeters (TLD) at different depths (0, 0.5, 1.0, and 2.0 cm) and distances from the applicator edge (0-58 cm) in a water-equivalent slab phantom with a different number of layers of LA shielding (0-5 layers). Measurements were performed by 6 × 6, 10 × 10, 14 × 14, and 20 × 20-cm2 applicators at a gantry and collimator angle of 0°. The out-of-field radiation dose profiles were normalized to the maximum dose of every energy and measuring depth. RESULTS: The out-of-field radiation doses (beyond 3 cm away from the field edge) decreased with an increase in the number of LA layers and distance away from the central beam axis (CAX). After shielding with the LA, the out-of-field doses decreased by up to approximately 99% compared with the no shielding group. For 4-MeV electron beams, there was a peak at 24.5 cm from the CAX, which weakened with an increasing number of LA layers. CONCLUSION: The shielding effect of the LA varied for a different number of LA layers as well as different depths and distances away from the CAX. Four LA layers were sufficient for shielding out-of-field doses of 4-15-MeV electron beams.

Sensitive immunoassay of cardiac troponin I using an optimized microelectrode array in a novel integrated microfluidic electrochemical device.

A sensitive and portable microfluidic electrochemical array device (µFED) was developed for the immunoassay of trace amounts of human cardiac troponin I (cTnI), which is an attractive biomarker for acute myocardial infarction (AMI). The classical "sandwich" method was adopted for the immunoassay. The capture antibody was immobilized using a self-assembled monolayer (SAM) technique, and the process was reorganized to be compatible with the bonding process. The detection antibody was labeled with alkaline phosphatase (AP) for signal amplification. The performance of the µFED was improved by eliminating the shielding effect of the microelectrode array (MEA) integrated in the µFED. The effects of the interstice and the width of the MEA on the response peak current were analyzed and simulated. The concentration gradient, about 3% of the gradient at the surface, was considered as the criterion for estimation of the optimal interstice between electrodes, and its effectiveness was proved. A stable and miniaturized reference electrode was integrated in the µFED, and its potential deviation was less than 5 mV in 15 min. These efforts resulted in the enhanced immunoassay performance of the µFED. A low limit of detection of about 5 pg/mL was obtained in serum samples, and the response current was proportional to the logarithm of concentration from 50 pg/mL to 1 µg/mL. The immunoassay process was accomplished in 15 min. The µFED was thus qualified and is a promising candidate for point-of-care immunoassay of cTnI. Graphical abstract.

Investigation of Bone Growth in Additive-Manufactured Pedicle Screw Implant by Using Ti-6Al-4V and Bioactive Glass Powder Composite.

In this study, we optimized the geometry and composition of additive-manufactured pedicle screws. Metal powders of titanium-aluminum-vanadium (Ti-6Al-4V) were mixed with reactive glass-ceramic biomaterials of bioactive glass (BG) powders. To optimize the geometry of pedicle screws, we applied a novel numerical approach to proposing the optimal shape of the healing chamber to promote biological healing. We examined the geometry and composition effects of pedicle screw implants on the interfacial autologous bone attachment and bone graft incorporation through in vivo studies. The addition of an optimal amount of BG to Ti-6Al-4V leads to a lower elastic modulus of the ceramic-metal composite material, effectively reducing the stress-shielding effects. Pedicle screw implants with optimal shape design and made of the composite material of Ti-6Al-4V doped with BG fabricated through additive manufacturing exhibit greater osseointegration and a more rapid bone volume fraction during the fracture healing process 120 days after implantation, per in vivo studies.

Shielding effect of a PEG molecule of a mono-PEGylated peptide varies with PEG chain length.

'Shielding' effect of a conjugated PEG molecule could cause a change in the electrostatic interaction characteristics of a PEGylate. We investigated how PEG chain length (or molecular weight) alters the electrostatic interaction potential of exenatide variants using their mono-PEGylates in a branched and linear form as model PEGylates. First, we performed the experiments to demonstrate the elution time changes of the mono-PEGylates conjugated with various MW PEGs (5, 10, 20, and 40 kD) using cation exchange chromatography (HiTrap® SP) at various pHs (2.5, 3.0, 3.5, and 4.0). Then, we calculated the net surface charge of each mono-PEGylate to propose the PEG molecule's shielding range in terms of the number of amino acids adjacent to the conjugation residue, assuming that a PEG molecule in solution sweeps out a spherical space and an exenatide molecule have a secondary structure. The net charge calculation result was well-correlated with the experimental elution time data, where 5, 10, 20, and 40 kD PEG hindered the electrostatic potential of 5, 8, 12, and 17 amino acid residues in maximum, respectively, on each side of the conjugation point.

Investigation of Scattered Radiation Reduction Effect by Use of Collimator Cover Covered with Leaded Sheet in Angiography Equipment.

The purpose of this study was to investigate the effect of scattered radiation reduction to medical staff by attaching the leaded sheet on the collimator cover of the angiography equipment. Ambient dose equivalent was measured to compare the rate of scattered radiation reduction between with and without the leaded sheet. Shielding effect was confirmed for scattered radiation in all directions, especially 27% of shielding ratio in the head and neck area when angiography equipment installed with small detector, and more than 40% of shielding ratio when adjusting a cut portion of leaded sheet to the field size. However, it decreased when the dose area product meter was not attached. Therefore, our proposed leaded sheet can reduce radiation dose to medical staff during angiographic and interventional procedures.

A Microdosimetric Study of Electropulsation on Multiple Realistically Shaped Cells: Effect of Neighbours.

Over the past decades, the effects of ultrashort-pulsed electric fields have been used to investigate their action in many medical applications (e.g. cancer, gene electrotransfer, drug delivery, electrofusion). Promising aspects of these pulses has led to several in vitro and in vivo experiments to clarify their action. Since the basic mechanisms of these pulses have not yet been fully clarified, scientific interest has focused on the development of numerical models at different levels of complexity: atomic (molecular dynamic simulations), microscopic (microdosimetry) and macroscopic (dosimetry). The aim of this work is to demonstrate that, in order to predict results at the cellular level, an accurate microdosimetry model is needed using a realistic cell shape, and with their position and packaging (cell density) characterised inside the medium.

Analysis of the interferences in quantitation of a site-specifically PEGylated exendin-4 analog by the Bradford method.

Protein modification has been found to affect the estimation of protein concentration in some of the traditional dye-based absorbance measurements. In this work, a distinct reduction in A595 was observed during the quantitation of a PEGylated exendin-4 analogue (Ex4C) by the Bradford method and the PEGylation process was found to interfere with the measurement. Lys(12), Arg(20), and Lys(27) were further proved to be the major amino acids that functioned as dye-binding sites. The shielding effect produced by the large polymer was demonstrated to depend on the length of PEG that was used for modification.

Bone graft incorporation failure with inappropriate limb load transfer can lead to aseptic acetabular loosening of metal-on-metal prosthesis: A case report.

BACKGROUND: Aseptic acetabular loosening can result from various factors that can be categorized into groups: patient-related, surgeon-related and implant-related. We present a case of a 63-year-old patient who at first underwent a total hip arthroplasty (THA) using a metal-on-metal bearing due to hip arthrosis. Follow-up visits revealed no complications after the procedure. Two years after the THA, acetabular component loosening occurred due to subsequent trauma of the opposite hip, necessitating a revision THA using a ceramic-on-ceramic bearing. CASE SUMMARY: We aim to illustrate a rare case where the primary reason for undergoing THA revision was not only incomplete bone graft incorporation but also improper limb load distribution. Following the revision arthroplasty, a 9-year follow-up visit revealed improvements in all evaluation measures on questionnaire compared to the state before surgery: Harris Hip Score (before surgery: 15; after surgery: 95), Western Ontario and McMaster Universities Arthritis Index (before surgery: 96; after surgery: 0), and Visual Analogue Scale (before surgery: 10; after surgery: 1). CONCLUSION: Opposite-hip trauma caused a weight transfer to the limb after a THA procedure. This process led to a stress shielding effect, resulting in acetabular component loosening.

Assessing the radiofrequency shielding effect of titanium mesh on diffusion-weighted imaging: a comparative study of the twice-refocused spin-echo and Stejskal-Tanner sequences.

This study compared twice-refocused spin-echo sequence (TRSE) and Stejskal-Tanner sequence (ST) to evaluate their respective effects on the image quality of magnetic resonance (MR) diffusion-weighted imaging in the presence of radiofrequency (RF) shielding effect of titanium mesh in cranioplasty. A 1.5-T MR scanner with a Head/Neck coil 20 channels and a phantom simulating the T2 and apparent diffusion coefficient (ADC) value of the human brain were used. Imaging was performed with and without titanium mesh placed on the phantom in TRSE and ST, and normalized absolute average deviation (NAAD), Dice similarity coefficient (DSC), and ADC values were calculated. The NAAD values were significantly lower for TRSE than for ST in the area below the titanium mesh, and the drop rates due to titanium mesh were 14.1% for TRSE and 9.8% for ST. The DSC values were significantly lower for TRSE than for ST. The ADC values were significantly higher for TRSE than for ST without titanium mesh. The ADC values showed no significant difference between TRSE and ST with titanium mesh. The ST had a lower RF shielding effect of titanium mesh than the TRSE.

Ultrasensitive 3D Stacked Silicon Nanosheet Field-Effect Transistor Biosensor with Overcoming Debye Shielding Effect for Detection of DNA.

Silicon nanowire field effect (SiNW-FET) biosensors have been successfully used in the detection of nucleic acids, proteins and other molecules owing to their advantages of ultra-high sensitivity, high specificity, and label-free and immediate response. However, the presence of the Debye shielding effect in semiconductor devices severely reduces their detection sensitivity. In this paper, a three-dimensional stacked silicon nanosheet FET (3D-SiNS-FET) biosensor was studied for the high-sensitivity detection of nucleic acids. Based on the mainstream Gate-All-Around (GAA) fenestration process, a three-dimensional stacked structure with an 8 nm cavity spacing was designed and prepared, allowing modification of probe molecules within the stacked cavities. Furthermore, the advantage of the three-dimensional space can realize the upper and lower complementary detection, which can overcome the Debye shielding effect and realize high-sensitivity Point of Care Testing (POCT) at high ionic strength. The experimental results show that the minimum detection limit for 12-base DNA (4 nM) at 1 × PBS is less than 10 zM, and at a high concentration of 1 µM DNA, the sensitivity of the 3D-SiNS-FET is approximately 10 times higher than that of the planar devices. This indicates that our device provides distinct advantages for detection, showing promise for future biosensor applications in clinical settings.

Beyond Mechanical Protection: The Electron-Shielding Effect of SWCNT for the Stabilized SiO Interface.

The single-walled carbon nanotube (SWCNT) commonly serves as a conductive additive for SiO-based anode materials due to the excellent conductivity and mechanical properties. However, the potential action mechanisms for the SWCNT beyond conductivity and mechanical features have rarely been studied. Herein, an interfacial electron-shielding effect and preferential adsorption to the electrolyte components for the SWCNT are revealed through a series of advanced characterizations and density functional theory (DFT) simulations. It can be determined that SWCNT networks could restrict the transmission of the electron from SiO interface to electrolyte with the reduced decomposition, because of the typical axial conductivity of the SWCNT. Moreover, the SWCNT shows stronger adsorption energy for LiPF6 and ethylene carbonate (EC) molecules, rather than nonselectivity of traditional carbon additives, facilitating the generation of inorganic-rich and denser solid electrolyte interface (SEI) film. As a result, benefiting from the electron-shielding effect, preferential adsorption, and mechanical protection, the SWCNT endows the SiO@C anode with a higher average Coulombic efficiency (CE) value of 99.4% over 100 cycles and a long cycling stability.

Effect of remaining pericervical dentin on biomechanical behavior of endocrown-restored molars with different materials: Three-dimensional finite element and Weibull analyses.

To evaluate the effect of remaining pericervical dentin (PCD) on the biomechanical behavior of endocrown-restored molars with different materials, six three-dimensional finite element (FE) models were reconstructed with different thicknesses and heights of pulp-chamber lateral dentinal wall (PCLDW). IPS Empress 2, In-Ceram Zirconia, and Lava Ultimate were selected as the materials. Compared with the Lava Ultimate FE models, the maximum tensile stress in the FE models using ceramics was higher in the endocrown and lower in the PCD surrounding it, and the overall failure probabilities with different PCLDW thicknesses and heights were similar, ranging from 9.8% to 12.9% under the normal lateral masticatory force, which were lower than the FE models using Lava Ultimate (ranging from 13.4% to 15.1%). Considering the bonding properties of ceramics, endocrown-restored molars using etchable lithium disilicate-reinforced glass ceramic exhibit superior longevity due to the stress shielding effect, regardless of the thickness and height of PCLDW.

Effects of Surface Treatment Conditions on the Bonding Strength and Electromagnetic Pulse Shielding of Concrete Using the 85Zn-15Al Arc Thermal Metal Spraying Method.

The surface treatment of concrete enhances the bonding of its metal coatings. Therefore, in the present study, on the concrete surface, prior to the deposit of an 85Zn-15Al coating via an arc thermal spraying process, different surface treatments were considered for the effective electromagnetic pulse (EMP) shielding properties of the concrete. However, the direct coating on a concrete surface possesses lower bond adhesion, therefore it is of the utmost importance to treat the concrete surface prior to the deposition of the metal coating. Moreover, to obtain better bond adhesion and fill the defects of the coating, the concrete surface is treated by applying a surface hardener (SH), as well as a surface roughening agent (SRA) and a sealing agent (SA), respectively. The metal spraying efficiency, adhesion performance, and bonding strength under different concrete surface treatment conditions were evaluated. The EMP shielding effect was evaluated under the optimal surface treatment condition. The proposed method for EMP shielding exhibited over 60% of spraying efficiency on the treated surface and a bonding strength of up to 3.9 MPa for the SH-SRA-SA (combining surface roughening and pores/defects filling agents) specimen compared to the control one, i.e., 0.8 MPa. The EMP shielding values of the surface-treated concrete with surface hardener, surface roughening agent, and sealing agent, i.e., SH-SRA-SA specimens, exhibited 96.6 dB at 1000 MHz. This was about 12 times higher than without coated concrete.

Can magnetic resonance imaging after cranioplasty using titanium mesh detect brain tumors?

This study determined the dependence of the concentration and position of contrast-enhanced tumors on the radio frequency (RF)-shielding effect of titanium mesh using the contrast-to-noise ratio (CNR) in magnetic resonance imaging (MRI). A phantom was constructed by filling a plastic container with manganese chloride tetrahydrate and agar. Four cellophane cylindrical containers were arranged from the end of the plastic container, and the brain tumor model was filled with gadobutrol diluted with NaCl, with molarity values of 0.2-1.0 mmol/L. The titanium mesh board was set on the left side of the phantom. Images were acquired using a 1.5-T MRI as well as two-dimensional spin-echo (2D SE) and three-dimensional fast spoiled gradient echo (3D FSPGR) sequences. CNR was calculated using the signal intensity values of the tumor model, surrounding area of the brain model, and background noise. Furthermore, the fractional change in CNR was calculated using values of CNR with and without the mesh. Moreover, a profile of CNR was created. The fractional change in CNR decreased at the brain tumor positions present near the mesh and at a contrast medium concentration of approximately ≤ 0.5 mmol/L in 2D SE and ≤ 0.25 mmol/L in 3D FSPGR. According to the CNR profiles, directly under the mesh, almost all contrast concentrations in 2D SE was unrecognizable; however, at a concentration of ≥ 0.5 mmol/L in 3D FSPGR was recognizable.