Terms Of Stability Research Articles

Operational Status and Future Plan of Proton Linear Accelerator at KOMAC

Since the second half of 2013, Korea Multi-purpose Accelerator Complex (KOMAC) has been supporting user beam service by using a 100-MeV proton linac and several beam line facilities. Proton beam service fields include various applications and research programs, such as material science, bio-medical science, semiconductor applications as well as nuclear physics and basic science. The 100-MeV linac is composed of an injector based on a 50-keV microwave ion source and two-solenoid LEBT (low energy beam transport), a 3-MeV RFQ with four-vane structure and conventional drift tube linac (DTL), where proton beam is accelerated from 3 MeV to 100 MeV. As the operation period of the proton accelerator exceeds 10 years and the cumulative operating time surpasses 30,000 hours, we judge that it is an opportune time to establish a long-term plan to prepare for the aging of the accelerator. To replace the currently operating RFQ, which shows degradation in performance (especially the beam transmission), we design a new RFQ with some modifications. For DTL, we are supposed to change the quadrupole magnet inside each drift tube from electromagnet type to permanent magnet type because the electromagnet has shown some trouble in view of long term stability. To leap forward in device and utilization technologies, we complete the construction of new facility of a Beam Test Stand (BTS) with a structure similar to the beam injection system (ion source, LEBT, RFQ) of the 100 MeV linear accelerator. We plan to actively conduct beam physics and accelerator research using this facility. Moreover, we are supposed to upgrade the proton linac to 1 GeV for spallation neutron source applications, which will be a long-term plan. In short term, we take phased approach with focusing the first phase at 200 MeV energy upgrade.

Bifunctional Mn‐Fe Oxide Catalysts for Zn‐Air Battery Air Electrodes Fabricated Through Atomic Layer Deposition

Zinc‐air batteries (ZABs) are one of many energy storage technologies that can help integrate renewable energy into the power grid. A key developmental goal for ZABs is replacing the precious metal catalysts at the air electrode with more abundant and inexpensive materials. In this work, a MnFexOy bifunctional catalyst is directly deposited on a ZAB air electrode using atomic layer deposition (ALD). With ALD, the atomic composition of the air electrode coating can be tuned based on catalytic activity. Characterization through electron microscopy, photoelectron spectroscopy and diffraction techniques indicate that the novel ALD film deposits as a nanocrystalline (Mn,Fe)3O4 cubic spinel. The mixed oxide catalyst outperforms its individual binary MnOx or FeOx constituents, operating at 50.7% bifunctional efficiency at 20 mA cm‐2. Moreover, the long term stability of the ALD catalyst is showcased by 600 h (1565 cycles) of ZAB cycling at 10 mA cm‐2. The efficiency retention of the bifunctional transition metal oxide catalyst is superior to a precious metal benchmark of Pt‐Ru‐C, with 84.7% efficiency retention after more than 1500 cycles versus only 66.2% retention for the precious metal catalyst. The ALD technique enables deep penetration of catalyst material into the air electrode structure, improving the cycling behaviour.

Elevating Charge Transport Layer for Stable Perovskite Light-Emitting Diodes.

Ion migration is a major factor affecting the long term stability of perovskite light-emitting diodes (LEDs), which limits their commercialization potential. The accumulation of excess halide ions at the grain boundaries of perovskite films is a primary cause of ion migration in these devices. Here, it is demonstrated that the channels of ion migrations can be effectively impeded by elevating the hole transport layer between the perovskite grain boundaries, resulting in highly stable perovskite LEDs. The unique structure is achieved by reducing the wettability of the perovskites, which prevents infiltration of the upper hole-transporting layer into the spaces of perovskite grain boundaries. Consequently, nanosized gaps are formed between the excess halide ions and the hole transport layer, effectively suppressing ion migration. With this structure, perovskite LEDs with operational half-lifetimes of 256 and 1774 h under current densities of 100 and 20mAcm-2 respectively are achieved. These lifetimes surpass those of organic LEDs at high brightness. It is further found that this approach can be extended to various perovskite LEDs, showing great promise for promoting perovskite LEDs toward commercial applications.

Study of long term stability of a 50 liters TPC, based on TRIPLE-GEM with optical readout, for the CYGNO experiment

The CYGNO project aims to study rare events, as low-mass (few GeV) Dark Matter (DM) particle or solar neutrino interactions, exploiting the approach of the optical readout of the scintillation light produced in the amplification in a multiple Gas Electron Multiplier (GEM) structure, of the primary ionization originated in large volume Time Projection Chamber (TPCs).The volume is filled with an He:CF4 gas mixture at atmospheric pressure. The 3D topology, and therefore direction of the recoils, is reconstructed thanks to the combined use of high-granularity, high sensitivity sCMOS cameras, for the precise tracking of the projection of the recoils on the GEM plane, and of fast light sensors in order to obtain the coordinate perpendicular to the camera plane.To conclude the R&D phase, the 50 L prototype, called Long Imaging ModulE (LIME), was moved underground at the Laboratori Nazionali del Gran Sasso (LNGS) in order to study the performance of the CYGNO experimental approach in a low background environment and to assess the contributions to the background from different sources, also comparing with Monte Carlo simulations.Stability studies and the effects of environmental condition on the light yield will be discussed, focusing on the effect of humidity on the detector response and stability amount and rate of self-sustaining micro-discharges. This is a crucial step towards the development of a large demonstrator.

Nanoporous silver fabricated with pretreated Ag–Al alloy toward surface enhanced Raman sensing

Nanoporous silver (NPS), characterized by its three-dimensional bi-continuous interpenetrating ligament channel structure, is a good candidate for surface enhanced Raman scattering (SERS), attributed to its exceptional surface-to-volume ratio and significant SERS enhancement capabilities. Here, we have successfully fabricated NPS through the dealloying of α-terpineol (α-TPN) coated Ag55Al45 alloy. The resulting α-NPS exhibits uniform ligaments and nanopore sizes, maintaining high SERS performance even after being exposed to air for more than one month. The pretreatment of precusor alloy with α-TPN is crucial not only for the formation of nanoporous structure but also for ensuring the long term stability of α-NPS. Specifically, α-TPN functions as a surfactant, facilitating atomic diffusion to achieve a superior interconnected NPS. Furthermore, during the dealloying process, the carbonization of α-TPN serves as a protective layer, effectively inhibiting the oxidation of silver.

#1504 Performance evaluation of MicroVue sC5b-9 for analysis of urine samples

Abstract Background and Aims Complement mediated kidney diseases including C3 glomerulopathy (C3G), atypical uremic syndrome (aHUS), lupus nephritis (LN), and immunoglobulin A nephropathy (IgAN) are chronic inflammatory conditions characterized by dysregulated complement activation. Traditionally, complement activation is measured in plasma. However, patients with kidney disease often have an abundance of complement activation fragments in their urine—including soluble C5b-9 (sC5b-9), a marker of terminal pathway activation—highlighting the potential value of sC5b-9 measurement in urine for diagnosis and risk management in patients with C3G, aHUS, LN, IgAN, and other kidney diseases. Herein we evaluated the analytical performance of the Quidel MicroVue sC5b-9 Plus EIA for measurement of sC5b-9 in urine. Method The Quidel MicroVue sC5b-9 Plus EIA was evaluated using randomly collected healthy urine samples or healthy urine samples spiked with a known concentration of sC5b-9, as well as chronic kidney disease (CKD) urine samples. Results The analytical performance of the Quidel MicroVue sC5b-9 Plus EIA for measurement of sC5b-9 in urine met acceptability criteria for accuracy and precision. Assay accuracy was (100 ± 20%) and intra-assay precision as well as inter-assay precision was ≤ 11% coefficient of variability (CV). sC5b-9 was not detected in healthy urine samples (N = 40), but sC5b-9 was detected in a subset of urine samples from patients with CKD (N = 10). Positive linearity was observed over a wide range of concentrations. sC5b-9 measured in urine was not affected by hemoglobin or triglyceride, and was stable following three freeze-thaw cycles. Lastly, sC5b-9 measured in urine was stable when stored at −20°C and –80°C for 4 weeks. Long term stability testing at –80°C is underway. Conclusion Quidel MicroVue sC5b-9 Plus EIA is an accurate, reliable assay for detection of sC5b-9 in urine samples.

Cognition in children with arachnoid cysts - A five-year follow-up after microneurosurgical fenestration.

In recent years there has been a re-evaluation regarding the clinical implications of temporal lobe arachnoid cysts (temporal arachnoid cysts) in children. These cysts have often been considered asymptomatic, or if symptomatic, only causing focal neurological symptoms or signs of increased intracranial pressure. However, several studies have more recently reported on cognitive symptoms improving after surgery. This study aimed to evaluate if reported cognitive improvement after surgery of temporal arachnoid cysts were stable after five years. Ten consecutive children (m = 14.65; range 12.1-19.415 were assessed cognitively five years after micro-neurosurgical fenestration of a temporal arachnoid cyst. Results were compared to results from their pre- and post-surgical evaluations. Evaluations included the Wechsler-scales, Boston Naming Test (BNT), Rey Auditory Verbal Learning Test (RAVLT), verbal fluency test (FAS) and Rey Complex Figure Test (RCFT). The analysis revealed significant postsurgical improvement compared to baseline on the Wechsler-scales measures of general intelligence (FSIQ), verbal abilities (VCI) and processing speed (PSI). Mean differences after surgery were 8.3 for FSIQ, (p = 0.026), 8.5 for VI (p = < .01) and 9.9 for PSI (p = 0.03). There were no significant differences in mean test results when comparing postsurgical scores with scores five years after surgery, indicating long-term stability of improvements. The results indicate that affected cognitive functions in children with temporal arachnoid cysts improve after surgery and that the improvements remain stable five years later. The improvements and long term stability were also consistent with the experience of both parents and children. The findings provide a strong argument for neurosurgical fenestration of temporal arachnoid cysts in children.

Synthesis of Cu doped NiO for their antioxidant and photocatalytic properties: Green synthesis using Lycopodium Linn

Metal oxide nanoparticles produced by plant extracts are more stable and biocompatible in comparison with those produced by physical and chemical methods. This research focuses on the synthesis of pure and Cu doped NiO nanoparticles (NPs) using Phytolacca dodecandra L'Herit (P.d) leaf extract and evaluation of their antioxidant and photocatalytic activities. The obtained Cu-doped NiONPs have been characterized through X-ray diffraction (XRD), Transmission electron microscope (TEM), Fourier transform infrared (FT-IR), Ultraviolet-visible (UV–Vis), N2 adsorption-desorption and X-ray photoelectron spectra (XPS) analyses in different concentrations (1, 3, and 5 %) of copper at an optimum temperature of 400 °C. The photocatalytic activity of prepared samples was studied by degradation of Rose Bengal (RB) and Methylene Blue (MB) dye aqueous solutions. Under UV radiation for 60 min. 5-Cu-NiO nanophotocatalyst showed degradation efficiency of 98.7 % (0.5 mol/L), high apparent constant (0.9871 min−1) and long term stability towards MB dye. In the antioxidant test, NiO NPs and Cu−NiO NPs prevented the oxidation of 50 % of the H2O2 molecules at a concentration of 363.96 and 350.29 μg/mL, respectively. Moreover, the enhancement of the antioxidant activity of the biosynthesized NiO NPs might be an effect of copper ions present in the particles. Facile and green synthesis process with the excellent degradation performance demonstrates that the Cu doped NiO NPs have a great potential for wastewater treatment applications.

High–performance copper–substituted La0.5Sr0.5CoO3 ceramics as economical functional materials for thick film resistors

The demand for cost–effective materials for thick film resistors has driven the exploration of alternative functional materials to replace the traditionally used ruthenium oxides. This study investigates the synthesis and properties of copper–substituted La0.5Sr0.5CoO3 (La0.5Sr0.5Co1-xCuxO3, LSCCu, x = 0.02–0.10) ceramics as a potential economical substitute. The crystal structure, electrical performance, and sintering behavior of LSCCu with varying Cu2+ contents were characterized through solid–state reactions and first–principles simulations. The results indicate that the perovskite structure is maintained with increasing Cu2+, while the densification temperature, crystallinity, and conductivity decrease. Moreover, Cu2+ substitution reduced the DOS across the Fermi level and weakened the electron transport in LSCCu. The sample with x = 0.06 exhibited a promising conductivity of 2609 S/cm after sintering at 1150 °C, comparable to commercial thick film resistor materials. The temperature coefficient of resistance (TCR) of LSCCu showed a metallic behavior with a low value of 1148 ppm/°C for the x = 0.06 sample. Additionally, the LSCCu ceramics possess good long–term stability and frequency stability of resistance. These findings suggest that LSCCu ceramics are a promising economical material for thick film resistor applications.

Shared xerophytic genes and their re-use in local adaptation to aridity in the desert plant Gymnocarpos przewalskii.

In order to thrive and survive, plant species need to combine stability in the long term and rapid response to environmental challenges in the short term. The former would be reflected by parallel or convergent adaptation across species, and the latter by pronounced local adaptation among populations of the same species. In the present study, we generated a high-quality genome and re-sequenced 177 individuals for Gymnocarpos przewalskii, an important desert plant species from North-West China, to detect local adaptation. We first focus on ancient adaptation to aridity at the molecular level by comparing the genomic data of 15 species that vary in their ability to withstand aridity. We found that a total of 118 genes were shared across xerophytic species but absent from non-xerophytic species. Of the 65 found in G. przewalskii, 63 were under purifying selection and two under positive selection. We then focused on local adaptation. Up to 20% of the G. przewalskii genome showed signatures of local adaptation to aridity during population divergence. Thirteen of the selected shared xerophytic genes were reused in local adaptation after population differentiation. Hence, only about 20% of the genes shared and specific to xerophytic species and associated with adaptation to aridity were later recruited for local adaptation in G. przewalskii.

Vitrification-enabled enhancement of proton conductivity in hydrogen-bonded organic frameworks

Hydrogen-bonded organic frameworks (HOFs) are versatile materials with potential applications in proton conduction. Traditional approaches involve incorporating humidity control to address grain boundary challenges for proton conduction. This study finds vitrification as an alternative strategy to eliminate grain boundary effect in HOFs by rapidly melt quenching the kinetically stable HOF-SXU-8 to glassy state HOF-g. Notably, a remarkable enhancement in proton conductivity without humidity was achieved after vitrification, from 1.31 × 10−7 S cm−1 to 5.62× 10−2 S cm−1 at 100 °C. Long term stability test showed negligible performance degradation, and even at 30 °C, the proton conductivity remained at high level of 1.2 × 10−2 S cm−1. Molecule dynamics (MD) simulations and X-ray total scattering experiments reveal the HOF-g system is consisted of three kinds of clusters, i.e., 1,5-Naphthalenedisulfonic acid (1,5-NSA) anion clusters, N,N-dimethylformamide (DMF) molecule clusters, and H+-H2O clusters. In which, the H+ plays an important role to bridge these clusters and the high conductivity is mainly related to the H+ on H3O+. These findings provide valuable insights for optimizing HOFs, enabling efficient proton conduction, and advancing energy conversion and storage devices.

Rentierism—Political Instability Nexus: The Danger of Oil-producing Region Crisis in Nigeria

The growing popularity of the rentier state theory has made the focus on the impact of oil rents on political stability central for revealing how natural resource (including oil) windfalls link to the weakness of institutional quality in any resource-rich economy. Considering the core characteristic of a rentier state (such as Nigeria)—a distributive political economy—the article examines how the stability of Nigerian political system can be affected by oil rents over the period 1996–2021. Through the adoption of autoregressive distributed lag (ARDL) bounds test to cointegration and vector error correction mechanism (VECM) for the test of long-run causality, the apparent effect of oil rents on Nigerian political development is reflected in the analyses and findings. Empirical evidence supports the oil impedes political stability assertion, as there is statistically valid negative association between oil rents and political stability in the short run and long run. It is demonstrated that oil wealth could offer greater incentives for civil conflicts, which have resulted in escalating political problems. In addition, the causality mechanism implies that the relationship found merely indicates association between oil rents and the level of political stability in the long term, and it is not causal. Thus, it is posited that through the adoption and implementation of sound policy measures, the escalation of conflicts would likely subside, especially in most oil-rich regions or states, whereas civil order could be promoted. It is, therefore, critical to enhancing fairness in the use and distribution of oil wealth, improving people’s welfare, particularly in the oil-producing communities and in general, ensuring that democratic principles in the management of resource windfalls are sustained. JEL: Q33, Q34, H56, H12

Ag-doped CuO nanoparticles embedded reduced graphene oxide nanocomposite from Punica granatum peel extract and evaluation of their photocatalytic activity and antimicrobial potential

The present study explored Punica granatum peel extract as a reducing and capping agent for synthesis of Ag-doped CuO nanoparticles embedded reduced graphene oxide (rGO) nanocomposite. The crystalline nature of the Ag doped CuO/rGO was identified utilizing X-ray diffraction (XRD) analysis. The surface morphology of Ag doped CuO/rGO was investigated by Scanning electron microscope (SEM) and transmission electron microscope (TEM) analysis. The surface elemental composition of the prepared material was investigated by the Energy dispersive spectra (EDS) analysis. Ag resulted in enhanced absorbance in the visible range as well as a reduction in band gap energy. The catalytic activity of the green synthesized Ag doped CuO/rGO photocataltyst was evaluated in the reduction of organic pollutants such as 4-nitrophenol (4-NP) and methylene blue (MB) in water at mild conditions. The results indicated that the biosynthesized Ag-CuO/rGO composites have very high and effective catalytic activity over MB dye (99.5 %), high rate constant (0.9871 min−1) and long term stability with 60 min irradiation of UV light. In addition, initial process parameters of catalyst dosage and MB concentration, and pH of the solution were also examined. Differential antimicrobial effects of doped and undoped CuO nanoparticles (NPs) against selected strains of bacteria and fungi were confirmed.

IrO2 nanoparticles supported on submicrometer-sized TiO2 as an efficient and stable coating for oxygen evolution reaction

The sluggish kinetics of the oxygen evolution reaction (OER) refers to the major contributor to the energy losses in electrowinning of metals. Improving the stability in the long term and activity of the electrocatalyst for OER take on a critical significance in reducing the energy consumption. An efficient and stable OER electrode (named as Ti/SMST/IrO2 electrode) was prepared in this study by supporting IrO2 nanoparticles on the surface of the submicrometer-sized TiO2 (SMST) interlayer. The obtained results indicated that the IrO2 nanoparticles approximately 14 nm in size were supported onto the submicrometer-sized TiO2 particles’ surface and exhibited a cactus-like morphology. The Ti/SMST/IrO2 electrode with the SMST interlayer prepared at 450 °C exhibited the highest electrocatalytic activity in terms of OER for its largest active surface area. This electrode showed an overpotential of 350 mV at a current density of 50 mA cm−2 and displayed a remarkable electrochemical stability of 443 h at a high current density of 2 A cm−2 in H2SO4 solution without significant change in OER activity. The prepared Ti/SMST/IrO2 electrode with high electrocatalytic performance is considered one of the promising electrodes for OER.

Performance increase for a medical proton beam ECRIS through dual frequency heating at MedAustron ion therapy center

The MedAustron facility, located in Wiener Neustadt, Austria, is a state-of-the-art synchrotron-based particle therapy center that provides irradiation with proton and carbon ion beams in an energy range of 62MeV to 252MeV and 120MeV/u to 402MeV/u, respectively. In order to improve on extracted current and on long term stability, key factors for medical accelerators, the dual frequency heating mode was tested at the source level. Through the use of dual frequency heating an increase in the intensity through the accelerator sections could be achieved, without changing the optics of the overall machine. The use of dual frequency heating has also improved the transmission efficiency from LEBT to LINAC section by 4 %. Across a wider range of input power, beam transmission is elevated when comparing to single frequency heating. As a result of this increased transmission, in room particle count could be improved in comparison to single frequency heating.

Stability and durability assessment of alum-tawed skin by light transmission analysis

Alum-tawed skin has been widely used in the past for the production of bookbindings elements because of its physical–mechanical properties and production process, easier and faster than that required for leather. Nevertheless, unlike for other skin-based materials employed in books production, such as parchment and leather, for alum-tawed skin the manufacturing process appears to be less standardized and rather few data are available in the literature on its durability and sensitivity to deterioration.In this work, a number of commercial samples of alum-tawed skin, from different manufactures and belonging to different animal species, were analysed by Light Transmission Analysis (LTA) to characterize their collagen hydrothermal stability, so as to gather useful information regarding their possible use for restoration works. The samples were then subjected to an artificial ageing process to assess their possible long term stability compared with that of some historical samples coming from 14th, 15th and 16th century bindings.The obtained results show that, as expected, the treatments the investigated alum-tawed skin samples undergo during the manufacture processes does not induce a level of stability of the collagen molecules higher than that of the vegetable and chrome tanning used for the leather treatment, although such treatment, in some cases, makes the alum-tawed skin slightly more stable than parchment. Moreover, accelerated ageing analysis showed that whatever the initial stability of the analysed samples, it decreases with ageing more rapidly and markedly than for parchment and leather, revealing a general lower durability of the alum-tawed skin to hydrothermal deterioration.

Green preparation of fiberboard waste derived N–doped carbon catalysts with tailored properties for efficient hydrogenation reduction of nitroaromatics

Biomass–derived carbon materials doped with diverse heteroatoms have demonstrated huge potentials for environment and energy applications, thanks to the availability, preferable porous and channel structures, and excellent conductivity and stability. In this work, fiberboard waste containing resin–based adhesive was selected for the green fabrication of N–doped carbon catalysts without using extra N–sources. A facile two–step calcination strategy with sequential carbonization and activation was proposed for generation and exposure of indispensable active sites, realizing the controllable regulation of textural and morphological characteristics. The resulting N–doped fiberboard derived carbon (NFC) samples possessed unique hierarchically porous structures with a significantly enlarged surface area, plentiful activity–dependent N species (e.g., graphitic N and pyridinic N), as well as suitable graphitization degree and surface hydrophilicity. As a result, a favorable adsorption procedure and an enhanced accessibility of active sites synergistically boosted the catalytic performance towards hydrogenation reduction of nitroaromatics. Taking the NFC–hh sample as paradigm, an excellent performance was demonstrated for 4–nitrophenol (4–NP) reduction, achieving a high apparent rate constant of 0.40 min−1 and an impressive turnover frequency of ∼0.20 mmol g−1 min−1. Besides, the continuous–flowing catalytic test exhibited an excellent conversion efficiency > 99.50% with a long–term stability over 100 h, showing an attractive prospect for industrial application. This work presents a new approach for high value–added utilization of biomass waste, and provides a low–cost and high–active catalyst for environmental remediation.

A correlated multi-observable assessment for vanadium redox flow battery state of charge estimation — Empirical correlations and temperature dependencies

The efficient operation of vanadium redox flow batteries requires the half cell specific monitoring of the state of charge (SOC). Monitoring of the SOC is affected by temperature fluctuations, which need to be distinguished from the SOC signal. Several SOC monitoring approaches have been proposed in the literature and either been evaluated individually or compared to one other approach. The aim of this study is to contribute to SOC sensor development for VRFB by providing a first correlated assessment of several established and new SOC monitoring methods. We perform multi observable measurements of: half cell electrolyte potentials, electrolyte densities, electrolyte volumes, electrolyte viscosity related pressure drops, pH related potentials and UV/Vis absorbances. We determine SOC correlations of these observables in full charge/discharge cycles at constant temperature and derive temperature corrections in additional measurements over a range of 12°C to 32°C at 25%, 50% and 75% SOC. We compare the SOC and temperature sensitivity as well as the accuracy of these monitoring methods at constant and varied temperature. We find that the established half cell electrolyte potentials and UV/Vis absorbances can estimate the SOC at constant temperature with measurement errors of 1.7% and 4%, respectively and with slightly higher errors at varying temperatures. The viscosity related pressure drop and electrolyte density are both suitable for SOC estimation if temperature corrections are included. The pH related potentials for the positive half cell and both half cell electrolyte volumes could be used for a rough SOC estimate, but need accurate temperature corrections and further long term stability evaluation.

Comparison of Cross-Pin Versus Cortical Button Femoral Fixation in Anterior Cruciate Ligament Reconstruction With Hamstrings Autograft: A Long-Term Clinical Study and Review of the Literature.

Background Anterior cruciate ligament reconstruction (ACLR) is a common operative procedure and many options regarding the type of the selected graft and fixation technique have been described to date. Although many studies have addressed the issue of the optimal femoral fixation device during ACLR with a hamstring tendon (HT) autograft, no clear evidence to indicate one technique over another has been found. Objective The purpose of this study was to compare the long-term postoperative outcomes and complication rates between transfemoral Cross-pin (CP) and Endobutton-Cortical Button (CB) fixation techniques in patients undergoing ACLR with an HT autograft. Methods One hundred and seven consecutive patients underwent ACLR by using a quadruple HT autograft that was stabilized with either a CP (CP Group: 52 patients) or a CB (CB Group: 55 patients) fixation technique. The Lachman test (LT), the Pivot-shift test (PST), the side-to-side difference in anterior translation of the tibia, the International Knee Documentation Committee (IKDC), and the Lysholm knee scoring systems were evaluated before surgery and during long-term follow up. Thefemoral and tibial tunnel diameter was measured in the anteroposterior (AP) and lateral radiographsafter surgery and at the final follow-up. Areview of the literature was also carried out to identify any differences between both techniques. Results Study groups were comparable in terms of patient demographics. The mean follow-up was 10.4 ± 1.3 and 10.6 ± 1.3 years in the CP and CB Groups, respectively (p = 0.47). In the CP Group, improvements after surgery in LT and PST from grade 2 (n=34) or 3 (n=18) to grade 0 (n = 41) or 1 (n = 11) and from grade 2 (n=36) or 3 (n = 16) to grade 0 (n = 44) or 1 (n = 8), respectively, were observed. In the CB Group, similar improvements in LT and PST scores from grade 2 (n = 40) or 3 (n = 15) to grade 0 (n = 46) or 1 (n = 9) and from grade 2 (n = 41) or 3 (n = 14) to grade 0 (n = 47) or 1 (n = 8), respectively, were observed. However, no differences between the groups (p = 0.53 for LT and p = 0.90 for PST) were noted. The mean Lysholm scores were 89.7 ± 6.8 and 90.2 ± 7.2 in the CP and CB groups, respectively (p = 0.59). Side-to-side difference improved from 9.1 ± 2.8 to 1.7 ± 1.5 mm and from 8.6 ± 2.5 to 1.6 ± 1.4 mm in the CP and CB groups, respectively (p = 0.89 between groups). According to IKDC grades, 92.1% and 91.4% of knees in the CP and CB groups, respectively were reported to be Grade A (Normal) or B (Nearly Normal) with a p = 0.7. Femoral and tibial tunnel widening was found in the last follow-up in both groups. However, there was no difference in the degree of tunnel widening among the two techniques.With respect to LT, PST, anterior drawer test, and IKDC score, none of the 15 published comparative studies demonstrated any significant differences between the two techniques and only one study detected a difference regarding the Lysholm score in favor of CP fixation. Conclusion In the long term, both CB and CP femoral stabilization techniques were shown to be associated with similar functional outcomes and low complication rates. Further large multicenter random clinical trials are still required to identify the most effective method of femoral fixation for HT autograft during ACLR surgery.

Fabrication of nickel foam/MXene/CoAl-layered double hydroxide by electrodeposition as electrode material for high-performance asymmetric supercapacitor

Layered double hydroxides (LDH) have become one of the highly promising electrode materials due to large specific area, excellent cycling stability and high energy density. However, the large internal resistance limits their applications in energy storage. The introduction of highly conductive materials is expected to solve this problem. In here, nickel foam (NF)/MXene/CoAl-LDH is prepared by electrodepositing CoAl-LDH on the surface of MXene-coated NF, and the effects of Co:Al ratio on the electrochemical properties are investigated in detail. The best electrochemical performance of the composite is obtained when Co:Al=2:1, with a specific capacitance of 646.7 F g−1 at 0.5 A g−1 and 450.8 F g−1 at 5 A g−1. Furthermore, the asymmetric supercapacitor is assembled with NF/MXene/CoAl-LDH as the positive electrode and activated carbon (AC) as the negative electrode. The voltage window of the device can reach 1.6 V. The specific capacitance of the device is 126.87 F g−1 at a current density of 0.5 A g−1. At the power density of 400 W kg−1, the energy density of 45.11 Wh kg−1 is provided. Even at the high power density of 4000 W kg−1, the energy density can still reach 17.88 Wh kg−1. After 5000 cycles at a current density of 5 A g−1, it still maintains a capacity retention rate of 92.9%. The asymmetric device with its high specific capacitance, long term stability and good power density and energy density has a great potential in energy storage applications.