129 research outputs found
Comparative study of Cu–Zn coatings electrodeposited from sulphate and chloride baths
In this work, the effect of the nature of the salt anion (chloride and sulphate) in the Cu–Zn citrate bath was investigated, using cyclic voltammetry (CV) and chronoamperometry (CA). Experimental electrodeposition parameters (switching potential and imposed potential) were varied in order to examine their influence on the deposits. The coating microstructures were observed by scanning electron microscope (SEM-EDS), the coating phases were characterized by X-ray diffraction (XRD) analysis and the surface composition was assessed by XPS. Higher current efficiency was obtained in chloride baths compared to sulphate baths and best deposits were obtained at −1.4Vvs.(Ag/AgCl/KCl) compared to −1.2 and −1.5Vvs.(Ag/AgCl/KCl). Corrosion test results in 0.5 M NaCl solution show that Cu–Zn deposit produced from chloride bath exhibited the highest corrosion resistance.</p
Assisted Self-Assembly to Target Heterometallic Mn-Nd and Mn-Sm SMMs: Synthesis and Magnetic Characterisation of [MnLn(O)(OH)(mdea)(piv)(NO)] (Ln=Nd, Sm, Eu, Gd)**
Assisted self-assembly by using a preformed [MnO(piv)(4-Me-py)(pivH)] (1) (pivH=pivalic acid) cluster leads to 3 different outcomes of the reaction with Ln(NO) ⋅ xHO (Ln=Pr−Ho and Y): MnLn and in some cases the inverse butterfly MnLn for Ln=Pr−Eu, MnLn for Ln=Tb-Ho and in the special case of Gd all three possibilities can form. Whilst the magnetic properties for the MnLn systems show the expected known SMM properties, for MnLn two new examples of Nd- and Sm-containing SMMs have been discovered.
in an assisted self-assembly approach starting from the [MnO(piv)(4-Me-py)(pivH)] cluster a family of Mn−Ln compounds (Ln=Pr−Yb) was synthesised. The reaction of [MnO(piv)(4-Me-py)(pivH)] (1) with N-methyldiethanolamine (mdeaH) and Ln(NO) ⋅ 6HO in MeCN generally yields two main structure types: for Ln=Tb−Yb a previously reported MnLn motif is obtained, whereas for Ln=Pr−Eu a series of MnLn clusters is obtained. Within this series the Gd analogue represents a special case because it shows both structural types as well as a third MnLn inverse butterfly motif. Variation in reaction conditions allows access to different structure types across the whole series. This prompts further studies into the reaction mechanism of this cluster assisted self-assembly approach. For the MnLn analogues reported here variable-temperature magnetic susceptibility measurements suggest that antiferromagnetic interactions between the spin carriers are dominant. Compounds incorporating Ln=Nd(2), Sm(3) and Gd (5) display SMM behaviour. The slow relaxation of the magnetisation for these compounds was confirmed by ac measurements above 1.8 K
Fe(III)-Citrate-Complex-Induced Photooxidation of 3-Methylphenol in Aqueous Solution
The photodegradation process of m-cresol (3-methylphenol), induced by Fe(III)-Cit complex, was investigated upon irradiation at 365 nm in natural water. The composition and photochemical properties of Fe(III)-Cit complex were studied by UV-Visible absorption spectrophotometer for optimizing the stoichiometry of the complex and photolysis under irradiation at 365 nm, respectively. A dark investigation of the system was performed before studying the photochemical behavior. The photooxidation efficiencies of m-cresol were dependent on the pH value, optimized at pH 2.86, oxygen, initial concentrations of Fe(III)-Cit complex, and m-cresol. Additionally, to look into the mechanism of m-cresol degradation using Fe(III)-Cit, tertiobutanol alcohol was used as scavenger for hydroxyl radicals and the result suggested that hydroxyl radical attack was the main pathway of m-cresol degradation. Besides, oxygen can enhance the photolysis of Fe(III)-Citrate complex by trapping the electron on the carbon centered radical formed after the photoredox process. Then O •− 2 formed reacts rapidly leading finally to formation of • OH radical. In absence of oxygen, less reactive species are formed; consequently the disappearance of m-cresol was strongly inhibited. Our work shows that the presence of Fe(III)-Citrate complex could have a considerable impact on the fate of organic pollutant in aquatic environment
From Green Chemistry to Healthy Environments: Silver Nanoparticles as a Dual Antioxidant and Antibacterial Agents for Advancing Biomedicine and Sustainable Wastewater Treatment
\ua9 2024 by the authors. The green synthesis of silver nanoparticles (AgNPs) using plant extracts is an eco-friendly method with potential for biomedical and environmental applications. This study aims to synthesize silver nanoparticles (SO-AgNPs) using Salvia officinalis L. extract and evaluate their antioxidant and antibacterial properties, positioning them as candidates for applications in sustainable biomedicine and wastewater treatment. S. officinalis L. extract was used to synthesize AgNPs under optimized conditions, with a 10% extract/AgNO₃ ratio and a reaction time of 180 min. The SO-AgNPs were characterized using ATR-FTIR, XRD, SEM, DLS, and Zeta potential analysis. The antioxidant activity of the extract and SO-AgNPs was evaluated using ABTS+• and DPPH• radical scavenging assays. Antibacterial activity was tested against 11 bacterial strains and bacteria isolated from industrial effluent, with minimal inhibitory concentrations (MIC) determined for both the extract and SO-AgNPs. The SO-AgNPs demonstrated potent antioxidant activity, with IC₅₀ values of 0.233 mg/mL and 0.305 mg/mL in the ABTS+• assay, and 0.173 mg/mL and 0.185 mg/mL in the DPPH• assay for the extract and SO-AgNPs, respectively. Antibacterial testing showed MIC values of 0.25 mg/mL for SO-AgNPs and between 3.12 and 6.25 mg/mL for S. officinalis L. extract against E. coli, P. aeruginosa, A. baumannii, MRSA, B. cereus, and S. epidermidis. For bacteria isolated from industrial effluent, the MIC values were 0.125 mg/mL for SO-AgNPs and 0.5 mg/mL for the extract. This study highlights the dual antioxidant and antibacterial capabilities of S. officinalis L. extract and SO-AgNPs, demonstrating their potential for use in both biomedical and environmental applications, including wastewater treatment
Systematic review and meta-analysis of clinical outcomes after management of posterior cruciate ligament tibial avulsion fractures
BACKGROUND: There is no consensus regarding the management of posterior cruciate ligament (PCL) avulsion fractures and the expected outcomes after treatment.
PURPOSE: To systematically review clinical outcomes and complications after management of tibial-sided avulsion fractures of the PCL.
STUDY DESIGN: Systematic review; Level of evidence, 4.
METHODS: A literature search of Scopus, PubMed, Medline, and the Cochrane Central Register for Controlled Trials was performed in accordance with the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Included were studies with evidence levels 1 to 4 that reported clinical outcomes after treatment of PCL tibial-sided avulsion fractures in humans. The quality of the included studies was performed using the Methodological Index for Non-Randomized Studies (MINORS) criteria. A meta-analysis was performed for patient-reported outcome measures using random-effects modeling with 95% CIs.
RESULTS: A total of 58 studies published between 1999 and 2022 were identified. The mean MINORS score was 9.90 ± 4.12, indicating overall low-quality evidence with high risk of bias. The studies comprised 1440 patients (mean age, 32.59 ± 5.69 years; 75.2% males) with a mean follow-up of 26.9 ± 19.6 months (range, 5.3-126 months). Most patients were treated with open surgery (63.6%), followed by arthroscopic surgery (29.7%) and nonoperative treatment (6.7%). All patients reported significant posttreatment improvement in both subjective and objective outcomes (
CONCLUSION: Although nonoperative and surgical management of PCL tibial avulsion fractures resulted in high rates of fracture union and improvement in functional outcome scores and a low incidence of complications, nonoperative treatment yielded a high side-to-side posterior displacement (\u3e4 mm) with a lower rate of fracture union compared to surgical treatment
Clinical outcomes, return to sport, and complications after isolated primary Latarjet versus Latarjet as a revision procedure: A systematic review and meta-analysis
BACKGROUND: The purpose of this review was to compare clinical outcomes, return to sport (RTS), and complications in comparative studies examining patients undergoing primary Latarjet procedure versus Latarjet in the revision setting following soft tissue stabilization.
METHODS: A literature search was conducted using PubMed and Scopus databases using Preferred Reporting Items for Systematic Meta-Analyses guidelines. Inclusion criteria consisted of level I to III human clinical studies reporting clinical outcomes (Visual Analogue Pain Scale [VAS]), RTS metrics, and complications in patients following primary versus revision Latarjet procedures. Study quality was assessed using the Methodological Index for Non-Randomized Studies (MINORS) criteria.
RESULTS: A total of seven studies, consisting of 1170 patients (n=1179 shoulders) with a mean age of 26.4 years, consisting of 91.9% males (n=1083/1179 shoulders), were identified. Mean final follow-up was 46.4 (mean range, 7.3-72.2) months. A total of 748 primary and 431 revision Latarjet procedures were analyzed. Complications were reported in 9.6% (range, 0%-24.2%) of patients undergoing primary and 20.2% (range, 0%-40.7%) in patients undergoing revision procedures (p=0.22). There was no significant difference in the RTS rate between patients undergoing primary (87.3%; range, 83.8%-92.1%) versus Latarjet as a revision procedure (78.9%; range, 60%-100%) (p=0.08). Moreover, no significant difference in postoperative VAS was observed in patients undergoing primary versus Latarjet as a revision procedure (p=0.21). Recurrent shoulder subluxation was significantly greater in patients undergoing revision (12.0%; n=31/259 shoulders; range, 0%-20.7%) compared to primary procedures (3.3%; n=27/511 shoulders; range, 0%-9%) (p\u3c0.001).
DISCUSSION: Patients undergoing primary and revision Latarjet demonstrated overall similar rates of complications and return to sport. Of clinical importance, Latarjet as a revision procedure possessed a risk of recurrent subluxation 3.6 times higher than primary Latarjet. While effective, patients should be counseled regarding the differing prognosis between Latarjet as a primary or revision procedure.
LEVEL OF EVIDENCE: III; Systematic review and meta-analysis
Adverse events and complications after primary ACL reconstruction with quadriceps tendon autograft: A systematic review
BACKGROUND: Anterior cruciate ligament reconstruction (ACLR) surgery with quadriceps tendon (QT) grafts, both with and without a patellar bone plug, have gained popularity in recent years in the primary and revision settings. Postoperative complications occur with the use of QT autografts.
PURPOSE: To systematically review the incidence of postoperative complications after primary ACLR QT autograft and compare complication rates in patients undergoing all-soft tissue QT grafts versus QT grafts with a patellar bone plug (QTPB).
STUDY DESIGN: Systematic review; Level of evidence, 4.
METHODS: A literature search using the 2020 PRISMA guidelines was performed by querying PubMed, Embase, and Scopus databases from database inception through August 2022. Included were evidence level 1 to 4 human clinical studies in English that reported complications after primary ACLR with QT autograft. The incidence of complications within the included studies was extracted. Differences in the incidence of postoperative complications between ACLR with QT with and without a patellar bone plug were calculated.
RESULTS: A total of 20 studies from 2004 to 2022, comprised of 2381 patients (2389 knees; 68.3% male) with a mean age of 27 years (range, 12-58 years), were identified. The mean follow-up was 28.5 months (range, 6-47 months). The total incidence of complications was 10.3%, with persistent postoperative knee pain being the most common (10.8%). Patients who underwent ACLR with all-soft tissue QT grafts had a 2.7-times increased incidence of anterior knee pain (23.3% vs 8.6%) and reoperations (5.9% vs 3.2%) when compared with QTPB grafts (
CONCLUSION: Complications after primary ACLR using QT autograft were recorded in 10.5% of knees, with anterior knee pain being the most common. No difference was reported in the overall incidence of complications with the use of the QT versus QTPB grafts; however, anterior knee pain was 2.7 times greater with use of a soft tissue quadriceps graft
Stranding of larval nase (Chondrostoma nasus L.) depending on bank slope, down-ramping rate and daytime
Rapid water level decreases due to hydropeaking are known to negatively affect riverine biota, mainly due to the stranding of organisms in the river bank area that becomes regularly dewatered. Even though studies of the last decades have focused on salmonid fish, also cyprinids may be affected. However, limited knowledge is available of this fish family. Therefore, we conducted mesocosm experiments under semi-natural conditions, simulating single hydropeaking events at two different lateral bank slopes (2% and 5%) with varying down-ramping rates (0.7–3.0 cm min−1) during day and night. As a response parameter, we quantified stranding rates of different larval stages (III-IV and V) of common nase (Chondrostoma nasus L.). The experiments revealed that lower sloped banks exhibited distinctly higher stranding rates than steeper ones. Daytime revealed a similar pattern, with more fish becoming stranded at night than during the day, and this was consistent for all down-ramping rates. The data also indicate increased stranding with higher down-ramping rates, particularly at low sloped riverbanks, and interaction effects between the tested parameters. Overall, this study, for the first time, quantifies the consequences of flow down-ramping on nase larvae, also revealing differences between larval stages. The gained information will, therefore, advance the ongoing discussion on hydropeaking mitigation by providing a deeper understanding of the effects of artificial sub-daily flow fluctuations on the early life stages of cyprinid fish. Our results can inform management and policy to sharpen existing mitigation concepts and fine-tune hydropower operations to reduce negative effects on riverine ecosystems
Radiofrequency-based chondroplasty creates a precise area of targeted chondrocyte death with minimal necrosis outside the target zone: A systematic review
PURPOSE: To systematically examine the effects of radiofrequency (RF) ablation or coblation (controlled ablation) on chondrocyte viability following knee chondroplasty in preclinical literature to determine the effectiveness and safety of RF-based techniques.
METHODS: A literature search was performed in September 2022 using PubMed and Scopus using the following search terms combined with Boolean operators: chondroplasty, radiofrequency, thermal, knee, chondral defect, articular cartilage, and cartilage. The inclusion criteria consisted of preclinical studies examining the effect of RF ablation or coblation on chondrocytes during knee chondroplasty. Exclusion criteria consisted of studies reporting chondroplasty in joints other than the knee, clinical studies, in vitro studies using animal models, case reports, non-full-text articles, letters to editors, surveys, review articles, and abstracts. The following data were extracted from the included articles: author, year of publication, chondral defect location within the knee and chondral characteristics, RF probe characteristics, cartilage macroscopic description, microscopic chondrocyte description, and extracellular matrix characteristics.
RESULTS: A total of 17 articles, consisting of 811 cartilage specimens, were identified. The mean specimen age was 63.4 ± 6.0 (range, 37-89) years. Five studies used monopolar RF devices, 7 studies used bipolar RF devices, whereas 4 studies used both monopolar and bipolar RF devices. Time until cell death during ablation at any power was reported in 5 studies (n = 351 specimens), with a mean time to cell death of 54.4 seconds (mean range, 23.1-64) for bipolar RF and 56.3 seconds (mean range, 12.5-64) for monopolar RF devices. Chondrocyte cell death increased with increased wattage, while treatment time was positively correlated with deeper cell death.
CONCLUSIONS: In this systematic review, histologic analysis demonstrated that RF-based chondroplasty creates a precise area of targeted chondrocyte death, with minimal evidence of necrosis outside the target zone. Caution must be exercised when performing RF-based chondroplasty due to the risk of cell death with increased application time and wattage.
CLINICAL RELEVANCE: Although RF ablation has demonstrated favorable results in preliminary trials, including smoother cartilage and less damage to the surrounding healthy tissue, the risks versus benefits of the procedure are largely unknown. Caution must be exercised when performing RF-based chondroplasty in the clinical setting due to the risk of cell death with increased application time and wattage
Nitrosorg : A research program dedicated to develop tools for improving grain quality (protein content and digestibility) and adapted to poultry feeding
The NitroSorg project is funded by CASDAR, Ministère de l'Agriculture et de l'Alimentation, France. It involves INRAE and CIRAD through the participation of the AGAP, IATE, BOA research units and the PEAT Experimental Unit, the Eurosorgho and RAGT2n seed companies, and the technical institute ITAVI. Although the SELMET research unit does not benefit directly of financial support of the project, it provides its expertise on feed quality phenotyping tools to the consortium. Nitrosorg will begin in 2022 and will last 42 months. It brings together a multidisciplinary consortium of biologists, geneticists, breeders, biochemists and poultry feed specialists to better understand the establishment of sorghum grain quality for poultry feeding and contribute to the development of breeding tools to optimize breeding efficiency for this target. Indeed, the low digestibility of sorghum grain proteins by gastrointestinal proteases, which has the particularity of decreasing even further after cooking, represents an important obstacle to a wider use of sorghum for feed but also for human nutrition. This low digestibility can be attributed to the interaction of proteins with other grain compounds such as starch or tannins, but is mainly related to the structure and properties of the storage proteins of sorghum grain (kafirins). One of the objectives of this project is to develop high-throughput characterization tools for the protein content and digestibility, but also starch and tannin content and endosperm texture that can affect this digestibility. The consortium will mobilize these tools to characterize the current European varietal offer, a panel representing the worldwide diversity, and the parental lines of the partner's breeding programs. Finally, we will carry, on a smaller panel of genotypes, an analysis of kafirin composition, and an exhaustive analysis of in vitro and in vivo protein digestibility (as part of poultry feeding). These analyses should allow us to assess the relevance of the high-throughput screening tools developed and will lead to the definition of the target ideotypes for poultry feeding. In the long term, these results will contribute to the development of grain sorghum varieties with a better protein content and digestibility, and therefore an improved nutritional value
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