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1.
Phys Eng Sci Med ; 2024 May 21.
Article in English | MEDLINE | ID: mdl-38771443

ABSTRACT

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.

2.
Int J Equity Health ; 23(1): 66, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38528545

ABSTRACT

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.


Subject(s)
Employment , Occupations , Humans , Educational Status , Chronic Disease
3.
Biosensors (Basel) ; 14(3)2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38534249

ABSTRACT

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.


Subject(s)
Biosensing Techniques , Nanowires , Nucleic Acids , Silicon/chemistry , Transistors, Electronic , DNA , Biosensing Techniques/methods , Nanowires/chemistry
4.
Sensors (Basel) ; 24(2)2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38276324

ABSTRACT

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.

5.
J Mol Model ; 29(8): 268, 2023 Aug 01.
Article in English | MEDLINE | ID: mdl-37528275

ABSTRACT

CONTEXT: This article is an initiation to build reasonable atomic/molecular theory to study chemicals utilized in different sectors of science including chemistry, biology, and medicine as well as the material science. It is all about opening new pathways and method-developments which need to be simple, reasonable, rational, and applicable to all chemicals and be closely consistent with the experimental data and real world. Hence, the success may simplify the process and eliminate the need to sophisticated software and heavy computations. The article first reviews the current classical atomic theory, and discusses some of its flaws. Then, it suggests a more reasonable approach through several presented simple formulas which would generate results consistent with the experimental data. Finally, the article goes through some examples, cases, and details to present the differences between the new suggested approach and the current classical atomic theory. Building new pathways would help not only with the ongoing scientific achievements but it would also help in classrooms and the education of next future generations. METHODS: All of the calculations and figures presented in this article are done by simple calculators and the use of Microsoft software including excel spreadsheet. The presented atomic theory does not need any sophisticated software and/or heavy computations. If desired, one can also use a simple personal programing technique to generate the desired results. So the key is in better understanding of the subjects and not in development of complicated computational tools and theoretical techniques. This article did not use any of the usual ab initio or DFT, or basis sets, or force field molecular-dynamics techniques. The focus of this article is mainly atomic theory which will expand to molecular theory in future articles.

6.
Dent Mater J ; 42(5): 683-691, 2023 Sep 29.
Article in English | MEDLINE | ID: mdl-37612061

ABSTRACT

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.


Subject(s)
Crowns , Dental Porcelain , Finite Element Analysis , Dental Stress Analysis , Ceramics , Molar , Dentin , Materials Testing
7.
Environ Pollut ; 334: 122147, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37429488

ABSTRACT

Radionuclides released and deposited because of the 2011 Fukushima Dai-ichi Nuclear Power Plant accident caused an increase in air dose rates in Fukushima Prefecture forests. Although an increase in air dose rates during rainfall was previously reported, the air dose rates in the Fukushima forests decreased during rainfall. This study aimed to develop a method to estimate rainfall-related changes in air dose rates, even in the absence of soil moisture data, in Namie-Town and Kawauchi-Village, Futaba-gun, Fukushima Prefecture. Moreover, we examined the relationship between preceding rainfall (Rw) and soil moisture content. The air dose rate was estimated by calculating the Rw in Namie-Town from May to July 2020. We found that the air dose rates decreased with increasing soil moisture content. The soil moisture content was estimated from Rw by combining short-term and long-term effective rainfall using half-live values of 2 h and 7 d and considering the hysteresis of water absorption and drainage processes. Furthermore, the soil moisture content and air dose rate estimations showed a good agreement with coefficient of determination (R2) scores >0.70 and >0.65, respectively. The same method was tested to estimate the air dose rates in Kawauchi-Village from May to July 2019. At the Kawauchi site, variation in estimated value is relatively large due to the presence of water repellency in dry conditions, and the amount of 137Cs inventory was low, so estimating air dose from rainfall remained a challenge. In conclusion, rainfall data were successfully used to estimate soil moisture and air dose rates in areas with high 137Cs inventories. This leads to the possibility of removing the influence of rainfall on measured air dose rate data and could contribute to the improvement of methods currently used to estimate the external air dose rates for humans, animals, and terrestrial forest plants.


Subject(s)
Fukushima Nuclear Accident , Radiation Monitoring , Soil Pollutants, Radioactive , Humans , Animals , Radiation Monitoring/methods , Soil , Soil Pollutants, Radioactive/analysis , Forests , Cesium Radioisotopes/analysis , Water , Japan
8.
ACS Nano ; 17(12): 11946-11956, 2023 Jun 27.
Article in English | MEDLINE | ID: mdl-37318040

ABSTRACT

Dendrite growth and electrode/electrolyte interface side reactions in aqueous zinc-ion batteries (AZIBs) not only impair the battery lifetime but also pose serious safety concerns for the battery system, hindering its application in large-scale energy storage systems. Herein, by introducing positively charged chlorinated graphene quantum dot (Cl-GQD) additives into the electrolyte, a bifunctional dynamic adaptive interphase is proposed to achieve Zn deposition regulation and side reaction suppression in AZIBs. During the charging process, the positively charged Cl-GQDs are adsorbed onto the Zn surface, acting as an electrostatic shield layer that facilitates smooth Zn deposition. In addition, the relative hydrophobic properties of chlorinated groups also build a hydrophobic protective interface for the Zn anode, mitigating the corrosion of the Zn anode by water molecules. More importantly, the Cl-GQDs are not consumed throughout the cell operation and exhibit a dynamic reconfiguration behavior, which ensures the stability and sustainability of this dynamic adaptive interphase. Consequently, the cells mediated by the dynamic adaptive interphase enable dendrite-free Zn plating/stripping for more than 2000 h. Particularly, even at 45.5% depth of discharge, the modified Zn//LiMn2O4 hybrid cells still retain 86% capacity retention after 100 cycles, confirming the feasibility of this simple approach for application with limited Zn sources.

9.
J Biol Chem ; 299(5): 104679, 2023 05.
Article in English | MEDLINE | ID: mdl-37028766

ABSTRACT

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.


Subject(s)
DNA Damage , DNA Repair , Epigenesis, Genetic , Pyrimidine Dimers/metabolism , Ultraviolet Rays/adverse effects
10.
Sci Total Environ ; 879: 163108, 2023 Jun 25.
Article in English | MEDLINE | ID: mdl-37003175

ABSTRACT

Graphene oxide (GO) is a representative novel carbonaceous nanomaterial, and neonicotinoid insecticides (NEOs) are currently the insecticides with the highest market share in the world. Their widespread application deservedly leads to their release to the environment. Thus, the complex interactions of these two types of organic compounds have attracted extensive attention. In this study, the effects of GO and its derivatives, reduced GO (RGO) and oxidized GO (OGO), on the photolysis of imidacloprid (IMD) (a typical NEO) under ultraviolet (UV) irradiation were systematically investigated. The results showed that the presence of the graphene-based nanomaterials (GNs) largely depressed the photodegradation of IMD, and the inhibition degree followed the order of RGO > GO > OGO. This was because the sp2 π-conjugated structure in the GNs caused light-shielding effect and attenuated the direct photolysis of IMD, even though the GNs-generated reactive oxygen species (ROS) promoted the indirect photodegradation of IMD to a certain extent. Additionally, the rich O-functionalized GO and OGO altered the photolysis pathway of IMD and induced more toxic intermediate products. These results highlight the implication of carbonaceous nanomaterials on the behavior, fate and potential risk of NEOs in aqueous systems.

11.
Nanomicro Lett ; 15(1): 81, 2023 Mar 31.
Article in English | MEDLINE | ID: mdl-37002511

ABSTRACT

Although their cost-effectiveness and intrinsic safety, aqueous zinc-ion batteries suffer from notorious side reactions including hydrogen evolution reaction, Zn corrosion and passivation, and Zn dendrite formation on the anode. Despite numerous strategies to alleviate these side reactions have been demonstrated, they can only provide limited performance improvement from a single aspect. Herein, a triple-functional additive with trace amounts, ammonium hydroxide, was demonstrated to comprehensively protect zinc anodes. The results show that the shift of electrolyte pH from 4.1 to 5.2 lowers the HER potential and encourages the in situ formation of a uniform ZHS-based solid electrolyte interphase on Zn anodes. Moreover, cationic NH4+ can preferentially adsorb on the Zn anode surface to shield the "tip effect" and homogenize the electric field. Benefitting from this comprehensive protection, dendrite-free Zn deposition and highly reversible Zn plating/stripping behaviors were realized. Besides, improved electrochemical performances can also be achieved in Zn//MnO2 full cells by taking the advantages of this triple-functional additive. This work provides a new strategy for stabilizing Zn anodes from a comprehensive perspective.

12.
Materials (Basel) ; 16(4)2023 Feb 06.
Article in English | MEDLINE | ID: mdl-36837002

ABSTRACT

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.

13.
Phys Eng Sci Med ; 46(1): 109-118, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36472801

ABSTRACT

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.


Subject(s)
Brain Neoplasms , Titanium , Humans , Magnetic Resonance Imaging/methods , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/surgery , Brain , Phantoms, Imaging
14.
Sci Bull (Beijing) ; 68(1): 56-64, 2023 Jan 15.
Article in English | MEDLINE | ID: mdl-36585306

ABSTRACT

The proposal of hybrid ion batteries, which can integrate the advantages of the single ion battery, opens up a new route for developing high-performance secondary batteries. Herein, we successfully constructed an aqueous hybrid battery comprised of polyanionic-type cathode material (Na3V2(PO4)3, NVP), Zn metal anode, and aqueous Ca2+/Zn2+ hybrid electrolyte. This exciting combination gives full play to not only the excellent diffusion dynamics of Ca2+ in the NASICON (sodium super ion conductors) structure but also the electrostatic shielding effect of Ca2+ with low reduction potential that inhibits the formation of zinc dendrites. As results, the NVP//Zn Zn/Ca hybrid battery delivers favorable specific capacity with outstanding rate performance (85.3 mAh g-1 capacity at 1 C, 60.5 mAh g-1 capacity at 20 C), and excellent cycle stability (74 % capacity retention after 1300 cycles).


Subject(s)
Calcinosis , Zinc , Humans , Calcification, Physiologic , Electrodes , Diffusion
15.
Polymers (Basel) ; 14(20)2022 Oct 12.
Article in English | MEDLINE | ID: mdl-36297854

ABSTRACT

Porous hydroxyapatite-gelatin (Hap-Gel) composite microspheres derived by wet chemical methods were used as carriers of doxorubicin (DOX) coupled with chitosan (Chi) for treating cancers. Through X-ray diffraction, specific surface area porosimetry, chemisorption analysis and inductively coupled plasma mass spectrometry, the crystalline phase, composition, morphology, and pore distribution of HAp-Gel microspheres were all characterized. HAp nanosized crystals and Gel polymers form porous microspheres after blending and exhibit a specific surface area of 158.64 m2/g, pore sizes from 3 to 150 nm, and pore volumes of 0.4915 cm3/g. These characteristics are suitable for carriers of DOX. Furthermore, by the addition of chitosan during drug loading, its drug-entrapment efficiency increases from 70% to 99% and the release duration increases from a 100% burst within a day to only 45% over half a year since the pores in the composite microspheres provide a shielding effect throughout the degradation period of the chitosan. According to the MTT tests, cell viability of DOX-Chi/HAp-Gel is 57.64% on day 5, similar to the result treated with DOX only. It is concluded that under the protection of pores in the microspheres, the chitosan abundant of hydroxyls combining HAp-Gel and DOX by forming hydrogen bonds indeed enhances the entrapment efficiency, prolongs the releasing period and maintains DOX's ability to perform medicine functions unaffected after loading.

16.
Phytochemistry ; 201: 113264, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35679970

ABSTRACT

Ten diphenyl ethers (DPEs), including nine undescribed analogs named betaethrins A-I, were isolated from the desert plant endophytic fungus Phoma betae A.B. Frank (Didymellaceae). Their structures were determined mainly by NMR, HR-ESI-MS spectral and X-ray diffraction experiments. Betaethrins D-I possessed different fatty acid chains connected with the B-ring, which was the first report in all DPEs. The shielding effect of the B-ring on H-6 (A-ring) in methyl barceloneate, betaethrin A and betaethrins D-F (asterric acid analogs) was first observed and analyzed, which could differentiate the 1H-NMR chemical shift values of H-4/H-6 without the assistance of 3-OH. An empirical rule was then suggested: the steric hindrance between the A- and B-rings in asterric acid analogs might prevent these two aromatic rings from rotating freely, which led to the 1H-NMR chemical shift value of H-6 being in the high field zone due to the shielding effect of the B-ring on H-6. Based on the empirical rule, the chemical shift values of the A-ring in methyl barceloneate were revised. The possible biosynthesis of these isolates was postulated. Betaethrin H showed moderate cytotoxicity against MCF-7 and HepG2 cancer cell lines. Betaethrins A-F, H and I displayed strong antioxidant activities. These results further implied that endophytic fungi from unique environments, such as desert plants, with few chemical studies are an important resource of undescribed and bioactive metabolites.


Subject(s)
Ascomycota , Endophytes , Ascomycota/chemistry , Endophytes/chemistry , Phenyl Ethers/chemistry , Phoma , Plants
17.
World Neurosurg ; 163: e310-e316, 2022 07.
Article in English | MEDLINE | ID: mdl-35390496

ABSTRACT

OBJECTIVE: Although cervical disc arthroplasty (CDA) has reportedly been associated with similarly low incidences of complications to anterior cervical discectomy and fusion, the phenomenon of anterior bone loss (ABL) is unique to CDA and has only recently gained notice. This study thus aimed to investigate the incidence of ABL and its correlation with cervical alignment post-operation. METHODS: Consecutive patients who received CDA for herniated disc or spondylosis were retrospectively reviewed. The development and extent of ABL was detected by comparison of preoperative and postoperative serial images for the relative position of the anterior vertebral body with the CDA devices and graded into 3 levels: grade 1 (minor bone loss), grade 2 (anterior portion of the vertebral body without exposure of the artificial disc), and grade 3 (anterior portion of the vertebral body with exposure of the device). RESULTS: A total of 41 patients were analyzed with a mean follow-up of 24.1 months. Under serial radiologic examinations during follow-up, all patients (41 of 41 = 100%) had bone loss of various degrees, with grade 3 ABL the most common (30 of 41 = 73.1%). There were 8 and 3 patients who had grades 2 and 1 ABL, respectively. The changes of the Cobb angle (ΔCobb) trended towards higher grades of ABL. CONCLUSIONS: During the mean follow-up of 2 years, ABL was a common radiologic finding. More than half of the patients (26 of 41, 63.4%) in the series gained cervical lordosis (ΔCobb >0) after CDA. These patients with increased cervical lordosis (ΔCobb >0) after CDA had higher grades of ABL.


Subject(s)
Bone Diseases, Metabolic , Intervertebral Disc Degeneration , Lordosis , Spinal Fusion , Total Disc Replacement , Arthroplasty/adverse effects , Arthroplasty/methods , Bone Diseases, Metabolic/complications , Cervical Vertebrae/diagnostic imaging , Cervical Vertebrae/surgery , Diskectomy/adverse effects , Diskectomy/methods , Humans , Intervertebral Disc Degeneration/complications , Intervertebral Disc Degeneration/diagnostic imaging , Intervertebral Disc Degeneration/surgery , Lordosis/diagnostic imaging , Lordosis/etiology , Lordosis/surgery , Retrospective Studies , Spinal Fusion/adverse effects , Spinal Fusion/methods , Total Disc Replacement/adverse effects , Treatment Outcome
18.
ACS Appl Mater Interfaces ; 14(2): 2833-2847, 2022 Jan 19.
Article in English | MEDLINE | ID: mdl-34982527

ABSTRACT

Two-dimensional (2D) layered transition-metal carbides (MXenes) are attractive faradic materials for an efficient capacitive deionization (CDI) process owing to their high capacitance, excellent conductivity, and remarkable ion storage capacity. However, the easy restacking property and spontaneous oxidation in solution by the dissolved oxygen of MXenes greatly restrict their further application in the CDI domain. Herein, a three-dimensional (3D) heterostructure (MoS2@MXene) is rationally designed and constructed, integrating the collective advantages of MXene flakes and MoS2 nanosheets through the hydrothermal method. In such a design, the well-dispersed MXene flakes can effectively reduce the aggregation of MoS2 nanosheets, boost electrical conductivity, and provide efficient charge transfer paths. Furthermore, MoS2 nanosheets as the high-capacity interlayer spacer can prevent the self-restacking of MXene flakes and provide more active sites for ion intercalation. Meanwhile, the strong chemical interactions between MXene flakes and MoS2 nanosheets contribute to accelerating the charge transfer kinetics and enhancing structural stability. Consequently, the resulting MoS2@MXene heterostructure electrode possesses high specific capacitance (171.4 F g-1), fast charge transfer and permeation rate, abundant Na+ diffusion channels, and superior electrochemical stability. Moreover, the hybrid CDI cell (AC//MoS2@MXene) with AC as the anode and MoS2@MXene as the cathode delivers outstanding desalination capacity (35.6 mg g-1), rapid desalination rate (2.6 mg g-1 min-1), excellent charge efficiency (90.2%), and good cyclic stability (96% retention rate). Most importantly, the MoS2@MXene electrode can keep good structural integrity after the long-term repeated desalination process due to the effective shielding effect of the MoS2 layer to protect MXenes from being further oxidized. This work presents the flexible structural engineering to realize excellent ion transfer and storage process by constructing the 3D heterostructure.

19.
Small ; 18(12): e2107115, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35098639

ABSTRACT

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.

20.
Radiol Phys Technol ; 15(1): 89-99, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34855114

ABSTRACT

This study aimed to compare the radiofrequency (RF) shielding effects of titanium mesh of echo-planar imaging (EPI) versus fast spin-echo (FSE) diffusion-weighted imaging (DWI) to establish a suitable sequence for patients who undergo cranioplasty and for whom titanium mesh was used in brain magnetic resonance imaging (MRI). A 1.5-T MRI scanner with clinical setting sequences was used. A phantom for the examination constructed using a sucrose solution in a plastic container was used to compare the signal attenuation (SA) ratio, area of RF shielding effect (Area), normalized absolute average deviation (NAAD), and apparent diffusion coefficient (ADC) between EPI and FSE-DWI. EPI provided significantly better SA ratio, Area, and NAAD (P < 0.01). When the number of slices increased, the RF shielding became more negative. There was no significant difference in the ADC. Regardless of the k-trajectory, EPI-DWI had a lower RF shielding effect than FSE-DWI in patients undergoing cranioplasty.


Subject(s)
Echo-Planar Imaging , Titanium , Brain/diagnostic imaging , Brain/surgery , Diffusion Magnetic Resonance Imaging/methods , Echo-Planar Imaging/methods , Humans , Magnetic Resonance Imaging/methods , Magnetic Resonance Spectroscopy
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