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Introduction: Magnetic resonance imaging (MRI) scans are increasingly used for knee osteoarthritis evaluation and preoperative planning before unicompartmental knee arthroplasty (UKA), and often patients already have MRI scans before their initial surgeon consultation. This highlights the need for surgeons to understand anteromedial osteoarthritis (AMOA) patterns on MRI. Hence, we aim to describe MRI findings in patients with AMOA meeting current indications for medial UKA. Materials and methods: We analysed MRI scans from 100 knees evaluated for UKA between 2006 and 2013. Inclusion criteria comprised full-thickness medial compartment loss and intact lateral compartment joint space on preoperative radiographs. Assessment included cartilage lesions, osteophytes, meniscal damage, and anterior-cruciate ligament (ACL) status on tibial and femoral surfaces. Final decision to proceed with UKA relied on intraoperative findings, independent of MRI. Results: Complete anteromedial tibial and femoral cartilage loss preserved posterior cartilage rims was evident in all cases. Cartilage thinning occurred in the lateral compartment in 34% of cases. While 62% displayed lateral osteophytes, only 6 exhibited small areas of full-thickness cartilage loss. ACL abnormalities varied: 27% normal, 3% ruptured, and 70% had intrasubstance high signal. Larger osteophytes in the medial (p = 0.012) and lateral (p = 0.002) intercondylar notch correlated significantly with ACL damage. All underwent medial UKA, with no evidence of areas with full lateral compartment cartilage loss intraoperatively. Conclusions: The MRI findings confirmed the radiographic diagnosis of bone-on-bone medial disease but highlights a range of findings in the ACL, lateral compartment, and patellofemoral joint compartment for patients who met the current x-ray and intraoperative indication for UKA. Further research is required to understand if these MRI changes will affect long-term outcomes. [ABSTRACT FROM AUTHOR]

This study examined mechanical properties of AA2024 alloy and its correlation between strain path and crystallographic texture. Accumulative roll bonding (ARB) and cross accumulative roll bonding (CARB) were used to severely deform AA2024 alloys. Electron backscatter diffraction (EBSD) studies demonstrated that nano/ultrafine grains were formed by the strain routes after eight cycles. It was also found that the lamellar boundary spacing and the mean boundary spacing were ~ 360 ± 10 nm and 845 ± 10 nm after eight ARB cycles. In contrast to the ARB, the CARB specimen had equiaxed microstructures characterized by grains with a size of 150 and 100 nm. The CARB processed specimen exhibited a mean misorientation angle of 41.83° and a fraction of high angle grain boundaries of 78%, these values were 34.57° and 67% for ARB treated specimen, respectively. It was observed that the evolved texture is greatly affected by the strain paths. The ARB processed specimen revealed strong Copper {112} <111>, Dillamor {4 4 11} <11 11 8>, S {123} <634>, and Brass {011} <211> components. In contrast, the CARB processed specimen showed major texture with prominent Copper {112} <111>, Brass {011} <211>, Rotated Cube {001} <110>, S {123} <634>, and Goss {011} <100> components. In the CARB specimen, the Goss/Brass texture ratio was intensified and the mechanical properties were superior (tensile strength: 535 MPa, microhardness: 182 HV, elongation: 11.9%) compared with the ARB processed specimen (tensile strength: 455 MPa, microhardness: 145 HV, elongation: 9.2%). Further, the change in strain path did not significantly affect the intensity of Goss and Cube components, ruling out any further recrystallization tendency. [ABSTRACT FROM AUTHOR]

The present study reported a green approach for the sonochemical-assisted synthesis (SAS) of copper oxide nanoparticles (CuO NPs) by using the aqueous extract of the Ficus johannis plant. The aqueous extract was obtained using ultrasonic-assisted extraction (15 min, 45 °C) and microwave-assisted extraction (15 min, 450 w). Next, the as-prepared extracts were used in a plant-mediated approach for the green synthesis of CuO NPs. The synthesized CuO NPs have been characterized via different techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), dynamic light scattering (DLS), ultraviolet–visible absorption, photoluminescence, and Fourier-transformed infrared (FT-IR) spectroscopic techniques. As observed, a broad absorption band around 375 nm clarified the successful synthesis of CuO NPs. From the SEM analysis, the average particle size of the prepared CuO NPs was estimated below 50 nm. In addition, the antimicrobial, antioxidant, and antifungal properties of the aqueous extracts as well as the as-prepared CuO NPs were evaluated by different assays. These included the release of protein, nucleic acids, disk diffusion method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), and time-killing assays. [ABSTRACT FROM AUTHOR]

Introduction: Prosthetic joint infection (PJI) is a destructive complication of knee replacement surgery (KR). In two-stage revision a spacer is required to maintain limb length and alignment and provide a stable limb on which to mobilise. Spacers may be articulating or static with the gold standard spacer yet to be defined. The aims of this scoping review were to summarise the types of static spacer used to treat PJI after KR, their indications for use and early complication rates. Methods: We conducted a scoping review based on the Joanna Briggs Institute's "JBI Manual for Evidence Synthesis" Scoping review reported following Preferred Reporting Items for Systematic Review and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) checklist. MEDLINE, EMBASE and CINAHL were searched from 2005 to 2022 for studies on the use of static spacers for PJI after KR. Results: 41 studies (1230 patients/knees) were identified describing 42 static spacer constructs. Twenty-three (23/42 [54.2%]) incorporated cement augmented with metalwork, while nineteen (19/42, [45.9%]) were made of cement alone. Spacers were most frequently anchored in the diaphysis (22/42, [53.3%]), particularly in the setting of extensive bone loss (mean AORI Type = F3/T3; 11/15 studies 78.3% diaphyseal anchoring). 7.1% (79 of 1117 knees) of static spacers had a complication requiring further surgery prior to planned second stage with the most common complication being infection (86.1%). Conclusions: This study has summarised the large variety in static spacer constructs used for staged revision KR for PJI. Static spacers were associated with a high risk of complications and further work in this area is required to improve the quality of care in this vulnerable group. [ABSTRACT FROM AUTHOR]

Introduction: With improved technology and technique, laparoscopic inguinal hernia repair (LIHR) has become a valid option for repairing both initial and recurrent inguinal hernia. Surgical residents must learn both techniques to prepare for future practice. We examined resident operative autonomy between LIHR and open inguinal hernia repair (OIHR) across the Veterans Affairs (VA) system. Methods: Utilizing the VA Surgical Quality Improvement Program database, we examined inguinal hernia repairs based on the principal procedure code at all teaching VA hospitals from July 2004 to September 2019. All VA cases are coded for level of supervision at the time of surgery: attending primary surgeon (AP); attending scrubbed but resident is a primary surgeon (AR), and resident primary with attending supervising but not scrubbed (RP). Primary outcomes were the proportion of LIHR versus OIHR and resident autonomy over time. Results: A total of 127,497 hernia repair cases were examined (106,892 OIHR and 20,605 LIHR). There was a higher proportion of RP (8.7% vs 2.2%) and lower proportion of AP (23.9% vs 28.4%) within OIHR compared to LIHR (p < 0.001). The overall proportion of LIHR repairs increased from 9 to 28% (p < 0.001). RP cases decreased for LIHR from 9 to 1% and for OIHR from 17 to 4%, while AP cases increased for LIHR from 16 to 42% and for OIHR from 18 to 30% (all p < 0.001). For RP cases, mortality (0 vs 0.2%, p > 0.99) and complication rates (1.1% vs. 1.7%, p = 0.35) were no different. Conclusions: LIHR at VA hospitals has tripled over the past 15 years, now compromising nearly one-third of all inguinal hernia repairs; the majority are initial hernias. Despite this increase, resident autonomy in LIHR cases declined alarmingly. The results demonstrate an urgent need to integrate enhanced minimally invasive training into a general surgery curriculum to prepare residents for future independent practice. [ABSTRACT FROM AUTHOR]

In this paper, metal-phase microextraction (MPME) was developed as a new solvent-free microextraction method based on iron. This technique is much safer in comparison with the liquid-phase and solid-phase microextraction procedures due to the elimination of organic solvents. In this method, NaBH4 is added to the sample solution containing Fe(II) ions. Therefore, metal ion analyte and Fe(II) ions are converted to zero-valent metals. During the aggregation of the zero-valent iron atoms, the analyte as the zero-valent form is trapped into the iron phase. Stirring during the procedure accelerates the aggregation of iron particles, leading to the formation of large particles, which can be easily separated using an applied external magnetic field. The extraction phase containing the analyte was dissolved in 200 µL of hydrochloric acid 6 N. In order to evaluate the performance of MPME, cadmium ion was selected as a test analyte and determined in real water samples and infant formula using a flame atomic absorption spectrometer. All affecting parameters, including pH, potassium hydrogen phthalate (KHP) concentration, Fe(II) and NaBH4 concentration, reaction time, and temperature, were investigated. Under the optimum conditions (pH 4, KHP 1 g L−1, NaBH4 0.6 g L−1, Fe2+ 12.5 mg L−1, reaction time 4 min, and temperature 55 °C), the limit of detection (LOD) and the relative standard deviation (RSD) were 0.10 ng mL−1 and 2.3%, respectively. The interfering effect of HCO3− and NO3− was eliminated by adding larger amounts of KHP and NaBH4, respectively. Relative recoveries of cadmium from the mineral, tap, and well water were 108.1, 102.2, and 115.3%. The infant food analysis according to ISO17025:2005 and MPME showed a cadmium concentration of 36 ± 6 ng g−1 and 40 ± 7 ng g−1, respectively, indicating that the two methods are not significantly different at the significance level of 0.05. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to perform a meta-analysis comparing mobile-bearing with fixed-bearing total knee arthroplasty (TKA) in terms of all-cause revision rates, aspetic loosening, knee functional scores, range of motion and radiographic lucent lines and osteolysis. Methods: PubMed, Cochrane Library, Google Scholar and Web of Science were searched up to January 2020. Randomized controlled trials that compared primary mobile-bearing with fixed-bearing TKA, reporting at least one of the outcomes of interest, at a minimum follow-up of 12 months were included. All outcomes of interest were pooled at short-term (< 5 years), mid-term (5 to 9 years) and long-term (> = 10 years) follow-up intervals. Results: A total of 70 eligible articles were included in the qualitative and statistical analyses. There was no difference between mobile-bearing or fixed-bearing TKA at short-term, mid-term and long-term follow-ups in all outcome measures including all-cause revision rate, aseptic loosening, oxford knee score, knee society score, Hospital for Special Surgery score, maximum knee flexion, radiographic lucent lines and radiographic osteolysis. Conclusion: The current level of evidence demonstrated that both mobile-bearing and fixed-bearing designs achieved excellent outcomes, yet it does not prove the theoretical advantages of the mobile-bearing insert over its fixed-bearing counterpart. The use of either design could therefore be supported based on the outcomes assessed in this study. Level of Evidence: Level II, Therapeutic [ABSTRACT FROM AUTHOR]

Nano/ultrafine-grained (NG/UFG) structure was produced in AA2024 alloy sheets by an accumulative roll bonding (ARB) and was subsequently joined by friction stir welding (FSW). Having evaluated the welded zone microstructurally and mechanically, this study's characterization confirmed the efficient and successful binding of these sheets through applying FSW. Localized Heat generation as a consequence of the FSW process caused the different regions of the weld nugget to have divergent grain structures. The texture components in the stir zone were Cube {001}〈100〉, S {123}〈634〉, B {112}〈110〉, C {001}〈110〉, and copper {112}〈111〉. Also, the grain growth phenomena, softening, and microhardness reduction were observed. [ABSTRACT FROM AUTHOR]

This article presents an ultrasound-assisted dispersive magnetic solid-phase extraction method (USA-DMSPE) to preconcentration Cd(II) and Pb(II) simultaneously. The adsorbent (mGO-βCD) was synthesized through three steps with consumption of environmentally friendly materials at room temperature. First graphene oxide (GO) was prepared via modified Hummer's method and then magnetized by Fe3O4 precipitation (mGO). Finally, β-cyclodextrin was covalently immobilized onto the surface of mGO. X-ray diffraction patterns established pure crystallinity of the materials. Homogenous distribution of magnetic nanoparticles onto GO sheets was confirmed by scanning electron microscopy and transmission electron microscopy. FT-IR spectra proved successful modification of mGO by β-CD. Alternating gradient force magnetometer characterized magnetic property. Brunauer–Emmett–Teller showed porous structure of mGO-βCD and having high surface area. pH (7 ± 0.2), adsorption time (2 min), adsorbent amount (20 mg), eluent kind (HNO3 (3 ml of 2.0 mol L−1)) and desorption time (one minute) were optimum conditions. Sonication disperses adsorbent in sample solution, which accelerates mass transfer, as well as decreasing adsorption time and adsorbent usage amount. Applicability of the method was investigated according to preconcentration factor (Pb(II): 200 and Cd(II): 167), linearity of dynamic range (Pb(II): (2–410) and Cd(II) (3–400 μg L−1), limit of detection (Pb(II): 0.64 and Cd (II): 0.9 μg L−1), relative standard deviation (Pb(II): 1.68% and Cd(II): 2.51%) and adsorption capacity (Pb(II): 188.68 and Cd(II): 78.12). mGO-βCD was reusable for ten times and durable in six months. Selectivity and effect of interference ions were reported. Obtained recoveries for real samples verified the satisfactory performance of the method. [ABSTRACT FROM AUTHOR]

By using the DFT and TD-DFT method, the potential of B12N12 nanocage to adsorb and detect of cyanogen fluoride (FCN) as a toxic gas molecule in the present of 1H+, 2H+, and 3H+ ions field and static electric field (SEF) were investigated at the WB97XD level of theory at the 6-31G (d, p) basis set. The structural and electrical parameters, adsorption energy, quantum descriptor, quantum theory of atom in the molecule (QTAIM), reduced density gradient (RDG), nonlinear optical properties (NLO), UV–Visible transitions, and thermodynamic parameters were calculated and results were analyzed. The adsorption energy (Eads), Enthalpy (ΔH) and Gibbs free energy (ΔG) values for all adsorption models were negative, and adsorption of FCN on the B12N12 nanocage was exothermic in the thermodynamic approach. The bandgap energy of all adsorption models is in the range of 7.60–11.08 eV, and with increasing the H+ ions functionalized and SEF, the bandgap energy of FCN/B12N12 complex decreased significantly from the pristine model, and so the conductivity and sensitivity of nanocluster increased. The QTAIM, ELF, LOL, and RDG results demonstrated that the attractive interaction between FCN and B12N12 in all models was a strong covalent bond. The NLO results revealed that the 3H+ functionalized B12N12 in presence of FCN was optically active. On the other hand, the calculated results demonstrated that the B12N12 nanocluster in the presence of 700 × 10−3 a.u electrostatic field (SEF0.70-z) and functionalizing 3H+ ions was a good strategy for adsorbing and making a sensitive sensor for FCN toxic gas. [ABSTRACT FROM AUTHOR]

Purpose: For patients with end-stage knee osteoarthritis, joint replacement is a widely used and successful operation to help improve quality-of-life when non-operative measures have failed. For a significant proportion of patients there is a choice between a partial or total knee replacement. Decision aids can help people weigh up the need for and benefits of treatment against possible risks and side-effects. This study explored patients' experiences of deciding to undergo knee replacement surgery to identify information priorities, to inform a knee replacement decision aid.Methods: Four focus groups were held with 31 patients who were candidates for both partial and total knee replacement surgery. Two focus groups included patients with no prior knee replacement surgery (pre-surgery); two with patients with one knee already replaced and who were candidates for a second surgery on their other knee (post-surgery). Data were analysed using Framework Analysis.Results: Participants described a process of arriving at 'readiness for surgery' a turning point where the need for treatment outweighed their concerns. Referral and personal factors influenced their decision-making and expectations of surgery in the hope to return to a former self. Those with previous knee surgery offered insights into whether their expectations were met. 'Information for decisions' details the practicality and the optimal timing for the delivery of a knee replacement decision aid. In particular, participants would have valued hearing about the experiences of other patients and seeing detailed pictures of both surgical options. Information priorities were identified to include in a decision aid for knee replacement surgery.Conclusions: Patients' experiences of surgical decision-making have much in common with the Necessity-Concerns Framework. Whilst originally developed to understand drug treatment decisions and adherence, it provides a useful lens to understand decision-making about surgery. The use of a decision aid could enhance decision-making on knee replacement surgery. Ultimately, patients' understanding of the risks and benefits of both surgical options could be improved and in turn, help informed decision-making. The knee replacement decision aid is perceived as a useful tool to be associated with other detailed information resources as recommended. [ABSTRACT FROM AUTHOR]

Purpose: Patient-specific instrumentation (PSI) has been proposed as a means of improving surgical accuracy and ease of implantation during technically challenging procedures such as unicompartmental knee arthroplasty (UKA). The purpose of this prospective randomised controlled trial was to compare the accuracy of implantation and functional outcome of mobile-bearing medial UKAs implanted with and without PSI by experienced UKA surgeons.Methods: Mobile-bearing medial UKAs were implanted in 43 patients using either PSI guides or conventional instrumentation. Intra-operative measurements, meniscal bearing size implanted, and post-operative radiographic analyses were performed to assess component positioning. Functional outcome was determined using the Oxford Knee Score (OKS).Results: PSI guides could not be used in three cases due to concerns regarding accuracy and registration onto native anatomy, particularly on the tibial side. In general, similar component alignment and positioning was achieved using the two systems (n.s. for coronal/sagittal alignment and tibial coverage). The PSI group had greater tibial slope (p = 0.029). The control group had a higher number of optimum size meniscal bearing inserted (95 vs 52%; p = 0.001). There were no differences in OKS improvements (n.s).Conclusion: Component positioning for the two groups was similar for the femur but less accurate on the tibial side using PSI, often with some unnecessarily deep resections of the tibial plateau. Although PSI was comparable to conventional instrumentation based on OKS improvements at 12 months, we continue to use conventional instrumentation for UKA at our institution until further improvements to the PSI guides can be demonstrated.Level Of Evidence: Therapeutic, Level I. [ABSTRACT FROM AUTHOR]

This article describes a useful sorbent for separation and preconcentration of trace amounts of gold(III), palladium(II) and silver(I) ions. Graphene oxide (GO) nanoparticles were synthesized by a modified Hummers method and magnetized by MnFeO nanoparticles to give a sorbent referred to as mag-GO. Addition of sodium dodecyl sulfate creates admicelles on the surface of the mag-GO. Then the metal chelating agent 2-mercaptobenzothiazole (MBT) was immobilized on mag-GO to give a mag-GO-MBT type material. This adsorbent was applied to the preconcentration of gold(III), palladium(II) and silver(I) ions. Following ion desorbed with a solution of thiourea, the ions were quantified by flow injection coupled to ICP-OES. Effect of sample pH value, type and volume of eluent, amount of adsorbent, sample volume, time of adsorption and desorption were optimized. Under optimized condition, the calibration plots are linear in the 2.5 to 25,000 μg.L concentration range. The limits of detection range from 0.045 to 0.076 μg.L, and enhancement factors are 160, 160 and 140 for gold, palladium and silver ions, respectively. Precisions, expressed as relative standard deviation for 100 μg.L of each ion are <3.1%. The nanosorbent applied to selective adsorption, extraction and preconcentration of Au(III), Pd(II), and Ag(I) from water, ore and automobile catalyst samples. [ABSTRACT FROM AUTHOR]

The authors describe the synthesis of a multifunctional nanocomposite with an architecture of type FeO@SiO@graphene quantum dots with an average diameter of about 22 nm. The graphene quantum dots (GQDs) were covalently immobilized on the surface of silica-coated magnetite nanospheres via covalent linkage to surface amino groups. The nanocomposite displays a strong fluorescence (with excitation/emission peaks at 330/420 nm) that is fairly selectively quenched by Hg ions, presumably due to nonradiative electron/hole recombination annihilation. Under the optimized experimental conditions, the linear response to Hg covers the 0.1 to 70 μM concentration range, with a 30 nM lower detection limit. The high specific surface area and abundant binding sites of the GQDs result in a good adsorption capacity for Hg (68 mg⋅g). The material, due to its superparamagnetism, can be separated by using a magnet and also is recyclable with EDTA so that it can be repeatedly used for simultaneous detection and removal of Hg from contaminated water. [ABSTRACT FROM AUTHOR]

Purpose: This randomized study investigates whether novices learning simulation-based arthroscopic skills in one anatomical joint environment can immediately transfer their learnt skills to another joint.Methods: Medical students were randomized to a simulated diagnostic knee or shoulder arthroscopic task on benchtop training models. After nine task repetitions over 3 weeks on one model, each participant undertook the simulation task of the other anatomical joint. Performance was objectively measured using a validated electromagnetic motion analysis system and a validated global rating scale (GRS).Results: Eighteen students participated; eight started the knee task and ten the shoulder task. All participants demonstrated a learning curve in all parameters during task repetition (time taken, hand path length, number of hand movements and GRS scores; p < 0.001) with learning effects >1 SD from initial performance (range 1.1-2.2 SD). When the groups swapped models, there was no immediate evidence of skill transfer, with a significant drop in performance between the final training episode and the transfer task (all parameters p < 0.003). In particular, the transfer task performance was no better than the first episode performance on that model by these novices.Conclusion: This study showed basic arthroscopic skills did not immediately transfer to an unfamiliar anatomical environment within a simulated setting. These findings have important clinical implications with regard to surgical training as they potentially challenge the assumption that arthroscopic skills acquired in one joint are universally transferrable to other joints. Future orthopaedic simulation training should aim to deliver exposure to a greater variety of arthroscopic procedures and joint environments. This would allow trainees to become familiar with the different arthroscopic setting before undertaking real surgery and consequently improve patient safety.Level Of Evidence: Therapeutic, Level II. [ABSTRACT FROM AUTHOR]

Purpose: To assess the construct and face validity of ArthroS, a passive haptic VR simulator. A secondary aim was to evaluate the novel performance metrics produced by this simulator.Methods: Two groups of 30 participants, each divided into novice, intermediate or expert based on arthroscopic experience, completed three separate tasks on either the knee or shoulder module of the simulator. Performance was recorded using 12 automatically generated performance metrics and video footage of the arthroscopic procedures. The videos were blindly assessed using a validated global rating scale (GRS). Participants completed a survey about the simulator's realism and training utility.Results: This new simulator demonstrated construct validity of its tasks when evaluated against a GRS (p ≤ 0.003 in all cases). Regarding it's automatically generated performance metrics, established outputs such as time taken (p ≤ 0.001) and instrument path length (p ≤ 0.007) also demonstrated good construct validity. However, two-thirds of the proposed 'novel metrics' the simulator reports could not distinguish participants based on arthroscopic experience. Face validity assessment rated the simulator as a realistic and useful tool for trainees, but the passive haptic feedback (a key feature of this simulator) is rated as less realistic.Conclusion: The ArthroS simulator has good task construct validity based on established objective outputs, but some of the novel performance metrics could not distinguish between surgical experience. The passive haptic feedback of the simulator also needs improvement. If simulators could offer automated and validated performance feedback, this would facilitate improvements in the delivery of training by allowing trainees to practise and self-assess. [ABSTRACT FROM AUTHOR]

The objective of the present study is to improve the behavior of sulfonated polyacrylamide (SPA) by adding Laponite and/or chromium(III) with a focus on enhanced oil recovery applications. The resultant systems are weak nanocomposite hydrogels which are subjected to rheological, thermal stability and adsorption tests. The interactions between ingredients of the hydrogel are investigated by Fourier transform infrared (FTIR) spectroscopy. In addition, dispersion of Laponite nanoparticles in hydrogel is confirmed by transmission electron microscopy (TEM). The thermal stability is determined by measuring the loss of viscosity after an aging cycle. The adsorption tests are performed on calcite and evaluated using thermo gravimetric analysis. FTIR spectra confirmed the interaction of Laponite and Cr with SPA. TEM micrograph showed an approximately uniform dispersion of Laponite in the crosslinked SPA/Cr/Laponite system. The viscoelastic behaviors of the systems improved with the addition of either Laponite or chromium(III). The sulfonated polyacrylamide/chromium(III)/Laponite system slightly loses its viscosifying power when subjected to harsh conditions of themo-chemical aging process. The adsorption behavior of the systems improved with Laponite concentration while the presence of chromium(III) weakened the adsorption. Therefore the introduced polymeric systems of the present study may be a potential option for enhanced oil recovery applications in hostile conditions. [ABSTRACT FROM AUTHOR]

The aim of this study was to outline the preparation of colloidal dispersion gels (CDGs) based on sulfonated polyacrylamide (SPA) and chromium triacetate and investigating their stability in harsh conditions. The effect of crosslinker, polymer concentration, salinity, and gelation time and temperature on the formation, rheological behavior and size distribution of CDGs and also their thermo-chemical stabilities were investigated. It was found that the shear viscosity and size of CDGs decreased with increasing of preparation time. Dynamic light scattering and scanning electron microscopy evaluations showed that the size of CDGs particles decreased with increasing of the Cr concentration. In addition, SPA solution had yield stress, while CDGs did not. The elevation of temperature inhibits while the salinity does not disturb the formation of CDGs. In the systems with lower polymer concentration, CDGs were formed. Conversely, in the systems with higher polymer concentration, bulk gels were formed. After aging, CDG sample had a minimal viscosity loss, indicating its exceptional thermo-chemical stability. [ABSTRACT FROM AUTHOR]

The authors describe the synthesis of core-shell structured FeO@graphene oxide nanospheres (denoted as FeO@GO NSs) via a chemical (covalent) bonding method. A chemical method was applied to cutting graphene oxide flakes into GO nanosheets. These were then covalently immobilized onto the surface of magnetite (FeO) nanoparticles. The material was characterized by TEM, SEM, EDX, FTIR, vibrating sample magnetometry and Raman spectroscopy. The data confirmed the coexistence of FeO and GO nanosheets with a core-shell structure. The FeO@GO NSs were applied to ferrofluid-based dispersive solid phase extraction of cadmium(II) as a model analyte using an ionic liquid carrier. This sorbent possesses as large contact surface area and a high density of polar groups on its surface. The nanoparticles, when finely dispersed in the sample solution, result in almost complete extraction of Cd(II) within a few seconds. Cd(II) was then quantified by FAAS. Under optimized conditions, the assay has the following features: (a) A detection limit of 0.12 ng mL, (b) a preconcentration factor of 250, (c) a relative standard deviation of 1.4 % (at a level of 50 ng mL; for n = 10); (d) a linear analytical range extending from 0.4 to 150 ng mL, (e) a maximal adsorption capacity of 33.7 mg g, and (e) a well expressed Langmuir adsorption isotherm. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

One of the main problems of polymer solutions in enhanced oil recovery applications is their properties losses after long term aging in electrolyte media. This paper reports preparation and rheological properties and thermal stability of novel weak hydrogels based on sulfonated polyacrylamide crosslinked in electrolyte solutions. Experimental results show that by increasing of crosslinker concentration, storage modulus dependency on frequency becomes weaker. At lower gelation temperature, gels with higher crosslinker concentrations exhibit lower storage modulus. Sharp decrease of viscosity value in viscosity-shear stress curves, approved existence of yield behavior for sulfonated polyacrylamide/chromium triacetate systems. There is a linear dependency of storage modulus, viscosity and yield stress value on polymer and crosslinker concentrations. Sulfonated polyacrylamide weakly crosslinked samples show higher viscosity than sulfonated polyacrylamide solution after thermal aging. Results of this research suggest the potentials of weakly crosslinked systems based on sulfonated polyacrylamide for oil recovery applications. [ABSTRACT FROM AUTHOR]

The role of genetic and epigenetic factors in the development of rheumatic diseases has been an interesting field of research over the past decades all around the world. Research on the role of microRNAs (miRNAs) in rheumatoid arthritis (RA) has been active and ongoing, and investigations have attempted to use miRNAs as biomarkers in disease diagnosis, prognosis, and treatment. This review focuses on experimental researches in the field of miRNAs and RA to present the data available up to this date and includes researches searched by keywords 'microRNA' and 'rheumatoid arthritis' in PubMed from 2008 to January 2015. All references were also searched for related papers. miRNAs are shown to act as proinflammatory or anti-inflammatory agents in diverse cell types, and their role seems to be regulatory in most instances. Researchers have evaluated miRNAs in patients compared to controls or have investigated their role by overexpressing or silencing them. Multiple targets have been identified in vivo, in vitro, or in silico, and the researches still continue to show their efficacy in clinical settings. [ABSTRACT FROM AUTHOR]

Graphene-based magnetic nanoparticles (G-FeO) were prepared and used as an effective adsorbent for the solid-phase extraction of trace quantities of cadmium from water and vegetable samples. The method avoids some of the time-consuming steps associated with traditional solid phase extraction. The excellent sorption property of the G-FeO system is attributed to π - π stacking interaction and hydrophobic interactions between graphene and the Cd-PAN complex. The effects of pH, the amount of G-FeO, extraction time, type and volume of eluent, desorption time and interfering ions on the extraction efficiency were optimized. The preconcentration factor is 200. Cd(II) was then quantified by flame atomic absorption spectrometry with a detection limit of 0.32 ng mL. The relative standard deviation (at 50 ng mL; for n = 10) is 2.45 %. The method has a linear analytical range from 1.1 to 150 ng mL, and the recoveries in case of real samples are in the range between 93.1 % and 102.3 %. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Purpose Methods Results Conclusion Level of Evidence The purpose of this study was to assess the efficacy of aspirin versus low‐molecular‐weight heparin (LMWH) in preventing venous thromboembolism (VTE) following hip and knee arthroplasty.PubMed/Medline, Embase, Cochrane Library and Google Scholar databases were searched from inception till June 2024 for original trials investigating the outcomes of aspirin versus LMWH in hip and knee arthroplasty. The primary outcome was VTE. Secondary outcomes included minor and major bleeding events, and postoperative mortality within 90 days. This review was conducted per the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines.A total of 7 randomized controlled trials with 12,134 participants were included. The mean ages for the aspirin and LMWH cohorts were 66.6 (57.6–69.0) years and 66.8 (57.9–68.9) years, respectively. There was no statistically significant difference in the overall risk of VTE between the aspirin and the LMWH cohorts (odds ratio [OR]: 0.95; 95% confidence interval [CI]: 0.48–1.89; p: 0.877). A subanalysis based on the specific VTE entity (pulmonary embolism [PE] or deep venous thrombosis) showed a significantly higher PE risk for patients receiving aspirin than the LMWH cohort (OR: 1.79; 95% CI: 1.11–2.89; p: 0.017). There was no difference in minor (OR: 0.64; 95% CI: 0.40–1.04; p: 0.072) and major bleeding (OR: 0.77; 95% CI: 0.40–1.47; p: 0.424) episodes across both groups. Furthermore, subanalysis among the total knee arthroplasty group showed that the aspirin cohort was significantly more likely to suffer VTEs than their LMWH counterparts (OR: 1.55; 95% CI: 1.21–1.98; p < 0.001).This study demonstrated a significantly higher risk of PE among patients receiving aspirin compared to LMWH following hip or knee arthroplasty for osteoarthritis. Aspirin was associated with a significantly higher overall VTE risk among patients undergoing knee arthroplasty, in particular. This might suggest the inferiority of aspirin compared to LMWH in preventing VTE following such procedures.Level I. [ABSTRACT FROM AUTHOR]

This article describes a method for highly selective preconcentration of Cd(II) via magnetic Mn2O3 coated by N,N′-bis(salicylidene)ethylenediamine (BSED). The metal oxide components were prepared via combining sol-gel and precipitation methods. Then, BSED was added as the third component of the composite. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, alternating gradient force magnetometry, and Fourier transform infrared spectroscopy were applied to characterize the materials. BSED selectively forms a complex with Cd(II), and the sorbent can then be magnetically separated. The preconcentration conditions were optimized as pH value (4.0 ± 0.5), sorbent amount (30 mg), adsorption time (20 min), eluent 2 M HNO3), eluent volume (1.5 mL) and desorption time (4 min). The quantification of Cd(II) was done by flame atomic absorption spectroscopy. The method has the following figures of merit: (a) a detection limit of 320 µg L−1, (b) a relative standard deviation of 1.1%, (c) an enhancement factor of 36, (d) a preconcentration factor of 33, and (e) a linear dynamic range that extends from 10 to 120 μg L−1. Other features include the use of safe reagents, fast and simple preparation, high selectivity and reliable analytical performance. The effects of potentially interfering ions were examined. The Dubinin–Radushkevich model and the pseudo second-order model are found to fit the adsorption behavior. The absorption is spontaneous and exothermic. The method was successfully applied to the determination of Cd(II) in (spiked) fruit samples. [ABSTRACT FROM AUTHOR]

The diagnosis of acute pyelonephritis in children remains a clinical challenge. We assessed the feasibility of magnetic resonance imaging (MRI) detection of pyelonephritis in four pediatric patients and compared the results with renal cortical scintigraphy. MRI revealed areas of high signal intensity in the kidney that coincided with photon-deficient regions in the radionuclide scans in two children with acute pyelonephritis. These findings confirm work in experimental animals and indicate that MRI can accurately detect acute pyelonephritis in children. [ABSTRACT FROM AUTHOR]