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Exploring efficacious low-Ir electrocatalysts for oxygen evolution reaction (OER) is crucial for large-scale application of proton exchange membrane water electrolysis (PEMWE). Herein, an efficient non-precious lanthanide-metal-doped IrO2 electrocatalyst is presented for OER catalysis by doping large-ionic-radius Nd into IrO2 crystal. The doped Nd breaks the long-ranged order structure by triggering the strain effect and thus inducing an atomic rearrangement of NdâIrO2 involving the forming of NdâOâIr bonds along with an increased amount of oxygen vacancies (Ov), giving rise of a long-ranged disorder but a short-ranged order structure. The formed NdâOâIr bonds tailor the electronic structure of Ir, leading to a lowered d-band center that weakens intermediates absorption on Ir sites. Moreover, doping Nd triggers NdâIrO2 to catalyze OER mainly through lattice oxygen mechanism (LOM) by activating lattice oxygen owing to abundant Ov. The optimal catalyst only requires a relatively low overpotential of 263 mV@10 mA cm-2 with a high mass activity of 216.98 A gIr -1 (at 1.53 V) (eightfold of commercial IrO2), and also shows a superior durability at 50 mA cm-2 (20 h) than commercial IrO2 (3 h) due to the oxidation-suppressing effect induced by Nd doping. This work offers insights into designing high-performance low-Ir electrocatalysts for PEMWE application.
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Thermal control at small scales is critical for studying temperature-dependent biological systems and microfluidic processes. Concerning this, optical trapping provides a contactless method to remotely study microsized heating sources. This work introduces a birefringent luminescent microparticle of NaLuF4:Nd3+ as a local heater in a liquid system. When optically trapped with a circularly polarized laser beam, the microparticle rotates and heating is induced through multiphonon relaxation of the Nd3+ ions. The temperature increment in the surrounding medium is investigated, reaching a maximum heating of ≈5 °C within a 30 µm radius around the static particle under 51 mW laser excitation at 790 nm. Surprisingly, this study reveals that the particle's rotation minimally affects the temperature distribution, contrary to the intuitive expectation of liquid stirring. The influence of the microparticle rotation on the reduction of heating transfer is analyzed. Numerical simulations confirm that the thermal distribution remains consistent regardless of spinning. Instead, the orientation-dependence of the luminescence process emerges as a key factor responsible for the reduction in heating. The anisotropy in particle absorption and the lag between the orientation of the particle and the laser polarization angle contribute to this effect. Therefore, caution must be exercised when employing spinning polarization-dependent luminescent particles for microscale thermal analysis using rotation dynamics.
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Polycrystalline yttrium aluminum garnet (YAG) ceramic doped with neodymium (Nd), referred to as Nd:YAG, is widely used in solid-state lasers. However, conventional powder metallurgy methods suffer from expenses, time consumption, and limitations in customizing structures. This study introduces a novel approach for creating Nd:YAG ceramics with 3D free-form structures from micron (â¼70 µm) to centimeter scales. Firstly, sol-gel synthesis is employed to form photocurable colloidal solutions. Subsequently, by utilizing a home-built micro-continuous liquid interface printing process, precursors are printed into 3D poly(acrylic acid) hydrogels containing yttrium, aluminum, and neodymium hydroxides, with a resolution of 5.8 µm pixel-1 at a speed of 10 µm s-1. After the hydrogels undergo thermal dehydration, debinding, and sintering, polycrystalline Nd:YAG ceramics featuring distinguishable grains are successfully produced. By optimizing the concentrations of the sintering aids (tetraethyl orthosilicate) and neodymium trichloride (NdCl3), the resultant samples exhibit satisfactory photoluminescence, emitting light concentrated at 1064 nm when stimulated by a 532 nm laser. Additionally, Nd:YAG ceramics with various 3D geometries (e.g., cone, spiral, and angled pillar) are printed and characterized, which demonstrates the potential for applications, such as laser and amplifier fibers, couplers, and splitters in optical circuits, as well as gain metamaterials or metasurfaces.
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Chemical methods for the extraction and refinement of technologically critical rare earth elements (REEs) are energy-intensive, hazardous, and environmentally destructive. Current biobased extraction systems rely on extremophilic organisms and generate many of the same detrimental effects as chemical methodologies. The mesophilic methylotrophic bacterium Methylobacterium extorquens AM1 was previously shown to grow using electronic waste by naturally acquiring REEs to power methanol metabolism. Here we show that growth using electronic waste as a sole REE source is scalable up to 10 L with consistent metal yields without the use of harsh acids or high temperatures. The addition of organic acids increases REE leaching in a nonspecific manner. REE-specific bioleaching can be engineered through the overproduction of REE-binding ligands (called lanthanophores) and pyrroloquinoline quinone. REE bioaccumulation increases with the leachate concentration and is highly specific. REEs are stored intracellularly in polyphosphate granules, and genetic engineering to eliminate exopolyphosphatase activity increases metal accumulation, confirming the link between phosphate metabolism and biological REE use. Finally, we report the innate ability of M. extorquens to grow using other complex REE sources, including pulverized smartphones, demonstrating the flexibility and potential for use as a recovery platform for these critical metals.
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Residuos Electrónicos , Metales de Tierras Raras , Metales , LigandosRESUMEN
In the present study, the synthesis of BaSrSiO4 co-doped Yb3+ and Nd3+ nanophosphors (NPs) was successfully achieved through the conventional sol-gel method, as confirmed by X-ray diffraction and SEM analysis, verifying the formation of pure NPs. The FTIR and Raman spectra analysis confirm the formation of silicates, as different modes and vibrations of Si-O and Si-O-Si were seen at 800-1000 cm-1. The energy transfer (ET) mechanism between Nd3+ and Yb3+ ions was seen as the emission spectra showed a rise in intensity of one over another. PLE emission spectra showed transitions at 2F7/2-2F5/2 for Yb3+ and from 4F3/2 to (4I9/2, 4I11/2, and 4I13/2) for Nd3+ when excited at 785 nm. All the samples record low activation energy, which shows that the rate of reaction will be higher in all the samples, and it will be highest for 1 mol% Nd3+ and 1 mol% Yb3+. An increasing value of τ was seen with increasing Yb3+ concentration, which confirms the increase in the population of trap centers. The positron annihilation lifetime (PAL) curve showed that 1 mol% Yb3+ and 2 mol Nd3+ have single vacancies or shallower positron traps, whereas 3 mol% Yb3+ and 2 mol% Nd3+ have larger defects like surface oxygen vacancy clusters. The other two samples have balance vacancies, which makes them best for thermometry applications. The fluorescence intensity ratio (FIR) was calculated to get sensitivity for thermometry application. 2.13% K-1 sensitivity achieved at 303-333 K temperature.
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BACKGROUND: Ingestion of multiple high-powered neodymium rare-earth magnets poses a significant risk for gastrointestinal (GI) injury such as bowel perforation or ischemia. Given the rising incidence of rare earth magnetic ingestions and the corresponding increase in serious injuries in children, published guidelines recommend urgent endoscopic removal of all magnets within endoscopic reach in cases involving ingestions of two or more magnets. RESEARCH QUESTION: Do management patterns for multiple magnet ingestion align with current practice guidelines, and does hospital length of stay (LOS) differ based on the initial emergency department (ED) approach? METHODS: This is a retrospective chart review of consecutive patient encounters reported to the New Jersey Poison Information and Education System (NJPIES) between January 2021 and April 2022 involving multiple magnet ingestion. Potential cases were retrieved from the NJPIES TOXICALL® database, using substance codes relating to magnet or foreign body ingestion. Two-sample T tests were used to determine the statistical difference in the hospital LOS between the group of patients receiving early emergent esophagogastroduodenoscopy (EGD) versus those receiving expectant management on initial presentation. RESULTS: There was a difference in the average LOS of 2.7 days (p = 0.023) longer in the expectant management group with no medical complications in either group. Twenty-five percent or 2 out of 8 cases deviated from guidelines. CONCLUSION: The initial ED decision to pursue expectant management instead of attempting emergent EGD removal of magnets may result in prolonged hospitalization, increased risk for readmission, and delayed definitive removal of magnets due to nonprogression along the GI tract.
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Cuerpos Extraños , Imanes , Niño , Humanos , Imanes/efectos adversos , New Jersey/epidemiología , Estudios Retrospectivos , Tracto Gastrointestinal/lesiones , Cuerpos Extraños/cirugía , Cuerpos Extraños/complicaciones , Ingestión de AlimentosRESUMEN
INTRODUCTION: Cataract extraction is the most frequently performed ophthalmological procedure worldwide. Posterior capsule opacification remains the most common consequence after cataract surgery and can lead to deterioration of the visual performance with cloudy, blurred vision and halo, glare effects. Neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy is the gold standard treatment and a very effective, safe and fast procedure in removing the cloudy posterior capsule. Damaging the intraocular lens (IOL) during the treatment may occur due to wrong focus of the laser beam. These YAG-pits may lead to a permanent impairment of the visual quality. METHODS: In an experimental study, we intentionally induced YAG pits in hydrophilic and hydrophobic acrylic IOLs using a photodisruption laser with 2.6 mJ. This experimental study established a novel 3D imaging method using correlative X-ray and scanning electron microscopy (SEM) to characterize these damages. By integrating the information obtained from both X-ray microscopy and SEM, a comprehensive picture of the materials structure and performance could be established. RESULTS: It could be revealed that although the exact same energies were used to all samples, the observed defects in the tested lenses showed severe differences in shape and depth. While YAG pits in hydrophilic samples range from 100 to 180 µm depth with a round shape tip, very sharp tipped defects up to 250 µm in depth were found in hydrophobic samples. In all samples, particles/fragments of the IOL material were found on the surface that were blasted out as a result of the laser shelling. CONCLUSION: Defects in hydrophilic and hydrophobic acrylic materials differ. Material particles can detach from the IOL and were found on the surface of the samples. The results of the laboratory study illustrate the importance of a precise and careful approach to Nd:YAG capsulotomy in order to avoid permanent damage to the IOL. The use of an appropriate contact glass and posterior offset setting to increase safety should be carried out routinely.
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Láseres de Estado Sólido , Lentes Intraoculares , Láseres de Estado Sólido/uso terapéutico , Imagenología Tridimensional , Microscopía Electrónica de Rastreo/métodos , HumanosRESUMEN
OBJECTIVE: Long-pulsed 1064 nm Nd:YAG laser can damage vessels with higher diameters and penetrate to a deeper level than other laser therapies. We aim to analyze outcomes of the treatment of leg veins with long-pulsed 1064 nm Nd:YAG laser regarding intervention protocol, technical success, clinical success, and side effects. METHODS: A research of the published literature was conducted, using PubMed and Embase databases, in April 2022. The key words used were telangiectasia, reticular veins, neodymium YAG laser, clearance, satisfaction, and treatment. PRISMA guidelines were followed. RESULTS: We included twenty-six articles, twenty-three prospective and three retrospective studies, with a total of 1991 patients. The articles were organized in different sections according to the control group. The four outcomes were analyzed in each section. These studies showed that the long-pulsed 1064 nm Nd:YAG laser is a safe and very good option for the treatment of leg veins measuring up to 3 mm in diameter. Studies comparing long-pulsed 1064 nm Nd:YAG laser therapy and sclerotherapy showed similar clearance rates with no significant differences. However, sclerotherapy seemed to be less painful and to have faster clinical improvements. In two articles, Nd:YAG laser had better outcomes in the treatment of smaller vessels with less than 1 mm in diameter, than sclerotherapy alone. Treatment with polidocanol microfoam and Nd:YAG laser had better clearance rates than Nd:YAG laser alone in three studies. In the comparison of 1064 nm Nd:YAG laser therapy with other lasers and light sources, the studies had contradictory results. CONCLUSION: Long-pulsed 1064 nm Nd:YAG laser is a valid therapeutic option for leg telangiectasia and reticular veins with great aesthetic outcomes and minor side effects. Nd:YAG laser therapy could be combined with sclerotherapy or other laser therapies or IPL in order to achieve better results. Serious side effects are rare, but the procedure is almost always accompanied by moderate tolerable pain.
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The damage excessive neodymium (Nd) causes to animals and plants should not be underestimated. However, there is little research on the impact of pH and associated ions on the toxicity of Nd. Here, a biotic ligand model (BLM) was expanded to predict the effects of pH and chief anions on the toxic impact of Nd on wheat root elongation in a simulated soil solution. The results suggested that Nd3+ and NdOH2+ were the major ions causing phytotoxicity to wheat roots at pH values of 4.5-7.0. The Nd toxicity decreased as the activities of H+, Ca2+, and Mg2+ increased but not when the activities of K+ and Na+ increased. The results indicated that H+, Ca2+, and Mg2+ competed with Nd for binding sites. An extended BLM was developed to consider the effects of pH, H+, Ca2+, and Mg2+, and the following stability constants were obtained: logKNdBL = 2.51, logKNdOHBL = 3.90, logKHBL = 4.01, logKCaBL = 2.43, and logKMgBL = 2.70. The results demonstrated that the BLM could predict the Nd toxicity well while considering the competition of H+, Ca2+, Mg2+ and the toxic species Nd3+ and NdOH2+ for binding sites.
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Neodimio , Contaminantes del Suelo , Neodimio/toxicidad , Triticum , Ligandos , Contaminantes del Suelo/toxicidad , Modelos Biológicos , Raíces de Plantas , Iones/farmacología , Concentración de Iones de HidrógenoRESUMEN
The aim of this research is to investigate novel compositions of oxyfluoride glasses doped with Neodymium (Nd3+) rare earth ions in the visible spectrum. This area has not been extensively studied in the existing literature, so it is vital to understand the favorable photoluminescence characteristics within this part of the electromagnetic spectrum. Therefore, we synthesized and characterized SiO2-PbO-PbF2 (SPF) doped with 1% neodymium (Nd3+) ions glasses. Spectroscopic analyses, based on Judd-Ofelt theory, were conducted on absorption spectra. These analyses enabled to determine absorption cross-sections, transition probabilities, and Judd-Ofelt intensity parameters Ω2, Ω4, and Ω6 for the different transition. Additionally, we calculated various radiative properties, such as branching ratios, integrated cross-sections, radiative lifetimes, emission cross-section, optical gain, and the multicolor behavior (chromaticity coordinates, CIE diagram) under different excitation wavelengths. The results suggest promising prospects for using these oxyfluoride silicate glasses doped with Nd3+ as a fluorophore, potentially for lasing materials around 630-nm emission and in other photonic applications.
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Vidrio , Neodimio , Silicatos , Dióxido de Silicio , Neodimio/química , Vidrio/química , Silicatos/química , Dióxido de Silicio/química , Fluoruros/química , Plomo/química , Óxidos/química , Fenómenos Ópticos , Luminiscencia , ColorRESUMEN
Nowadays, lasers are used in various medical fields. Ophthalmology was the first medical specialty to utilize lasers in patient treatment and still remains the leading medical field that uses laser energy for both therapeutic and diagnostic purposes. The neodymium: yttrium-aluminum-garnet (Nd: YAG) laser is one of the most common lasers used in ophthalmology. It is a solid-state laser with a wavelength of 1064 nm that works on the principle of photodisruption. Since its introduction in ophthalmology over 40 years ago, it has found various applications, mainly for procedures where cutting or disruption of ocular tissue is required. Compared to surgical alternatives, the use of Nd: YAG lasers on ocular tissue is minimally invasive. In this review, we focus on the two most common ophthalmic applications of Nd: YAG laser - laser peripheral iridotomy and posterior capsulotomy. The history of the techniques, current trends, potential complications, and the prognosis for future use is discussed.
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Láseres de Estado Sólido , Humanos , Láseres de Estado Sólido/uso terapéutico , Terapia por Láser/métodos , Terapia por Láser/instrumentación , Capsulotomía Posterior/métodos , Iridectomía/métodos , Oftalmología , Iris/cirugíaRESUMEN
OBJECTIVE: The study aims to determine the effects of Nd:YAG laser-assisted with subgingival scaling and root planing (SRP) treatment on glucose control and the dynamic changes of subgingival microbiome in periodontitis with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: Twenty-two patients were split into Nd:YAG group (n = 11) and SRP group (n = 11). Patients in the Nd:YAG group received SRP and auxiliary Nd:YAG laser treatment; patients in the SRP group received SRP treatment only. Periodontal tissue inflammation and glycemic control were assessed and analyzed during the treatment period and the changes of subgingival microbiome were analyzed by full-length 16S rRNA sequencing. RESULTS: After 3 months of treatment, PD and CAL values improved significantly in the Nd:YAG group compared to the SRP group. BOP in both groups improved significantly after treatment. FPG levels in the Nd:YAG group were significantly reduced after treatment. Porphyromonas and Porphyromonadaceae were enriched in the Nd:YAG group at baseline, and Fusobacteriota, Fusobacteriia, Fusobacteriales, Leptotrichiaceae, and Leptotrichia were enriched after treatment. CONCLUSION: Nd:YAG laser-assisted SRP therapy has additional benefits in improving periodontal tissue inflammation and blood glucose control in periodontitis patients with T2DM compared with SRP therapy alone and there was a trend towards a decrease in disease-associated taxa and an increase in health-associated taxa following auxiliary Nd:YAG laser treatment. CLINICAL RELEVANCE: The effects of Nd:YAG laser-assisted SRP treatment on inflammation, glucose control, and subgingival microbiome in periodontitis patients with T2DM were elucidated, and new ideas for the treatment of T2DM periodontitis were provided.
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Diabetes Mellitus Tipo 2 , Terapia por Láser , Láseres de Estado Sólido , Periodontitis , Humanos , Animales , Aplanamiento de la Raíz , Glucemia , Diabetes Mellitus Tipo 2/complicaciones , ARN Ribosómico 16S , Raspado Dental , Periodontitis/complicaciones , Periodontitis/terapia , InflamaciónRESUMEN
A comprehensive understanding of intercellular and cell-matrix interactions is essential for advancing our knowledge of cell biology. Existing techniques, such as fluorescence microscopy and electron microscopy, face limitations in resolution and sample preparation. Supravital lanthanoid staining provides new opportunities for detailed visualization of cellular metabolism and intercellular interactions. This study aims to describe the structure, elemental chemical, and probable origin of zones of extreme lanthanoid (neodymium) accumulation that form during preparation for scanning electron microscopy (SEM) analysis in corneal fibroblasts filopodia. The results identified three morphological patterns of neodymium staining in fibroblast filopodia, each exhibiting asymmetric staining within a thin, sharp, and extremely bright barrier zone, located perpendicular to the filopodia axis. Semi-quantitative chemical analyses showed neodymium-labeled non-linear phosphorus distribution within filopodia, potentially indicating varying phosphate anion concentrations and extreme phosphate accumulation at a physical or physicochemical barrier. Phosphorus zones labeled with neodymium did not correspond to mitochondrial clusters. During apoptosis, the number of filopodia with extreme and asymmetric phosphorus accumulation increases. Supravital lanthanoid staining coupled with SEM allows detailed visualization of intercellular and cell-matrix interactions with high contrast and resolution. These results enhance our understanding of phosphate anion accumulation and transfer mechanisms in cells under normal conditions and during apoptosis.
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Fibroblastos , Neodimio , Fosfatos , Seudópodos , Seudópodos/metabolismo , Seudópodos/ultraestructura , Fibroblastos/metabolismo , Fibroblastos/citología , Fosfatos/metabolismo , Neodimio/metabolismo , Humanos , Microscopía Electrónica de Rastreo , Coloración y Etiquetado/métodos , Apoptosis , Comunicación CelularRESUMEN
The use of rare earth elements (REEs) has been increasing and one of the most used is neodymium (Nd). Being an emergent contaminant, its negative impacts are poorly understood. Aquatic organisms are also threatened by climate change-related factors, as is the case of warming, which can change the effects of REEs. Thus, the impacts of Nd, warming, and the combination of both stressors were studied in adult mussels and sperm of the species Mytilus galloprovincialis, after an exposure period of 28 days (adults) and 30 min (sperm). The effects were evaluated through the analysis of biochemical and histopathological alterations in adults and biochemical and physiological responses given by sperm. The results showed that mussels only activated their biotransformation capacity when exposed to the stressors acting alone, which was insufficient to avoid lipid peroxidation. Furthermore, warming (alone and combined with Nd) also produces damage to proteins. The digestive gland was the most sensitive organ to Nd, presenting several histopathological alterations. In the case of sperm, all stressors induced lipid peroxidation, a higher oxygen demand, and a decrease in velocity, even if the sperm viability was maintained. It seems that warming influenced the effects of Nd to some extent. The present findings contribute significantly to the field of REEs environmental toxicology by offering valuable insights into the impacts of Nd on various biological levels of mussels. Additionally, within the context of climate change, this study sheds light on how temperature influences the effects of Nd. The obtained results indicate that both stressors can potentially compromise the overall health of mussel populations, thereby affecting other species reliant on them for food and habitat. Moreover, this study highlights impaired sperm health, which could adversely affect their reproductive capacity and ultimately lead to population decline.
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Mytilus , Neodimio , Espermatozoides , Animales , Mytilus/fisiología , Masculino , Peroxidación de Lípido , Cambio Climático , Contaminantes Químicos del Agua/toxicidadRESUMEN
OBJECTIVE: To evaluate the effectiveness of combining high-intensity focussed ultrasound and a Q-switched neodymium-doped yttrium aluminium garnet 1064nm low-fluence toning laser in the treatment of melasma. METHODS: The experimental study was conducted from November 2020 to August 2021 at the medical physics laboratory, College of Medicine, Mustansiriyah University, Baghdad, Iraq, and comprised individuals of either gender aged >25 years having mixed form melasma in malar and forehead areas. Each participant received high-intensity focussed ultrasound treatment on the right side. After 2 weeks, Q-switched neodymium-doped yttrium aluminium garnet 1064nm low-fluence toning laser was applied to the melasma patches 4 times at one-week intervals. Melasma area and severity index scores were noted at baseline and at each visit for each patient. Visual analogue scale was used for objective evaluation. After the 4 laser sessions, all the patients completed a 3-month follow-up. Data was analysed using SPSS 24. RESULTS: Of the 25 subjects, 15(60%) were females and 10(40%) were males. The overall mean age was 41.6±8.46 years (range: 22-60 years). There was a significant improvement with high-intensity focussed ultrasound (p<0.05). In the 3rd laser session, there was a significant difference in melasma area and severity index score of 2.48 for the right side and 3.12 for the left side (p<0.05). In the 4th session, there was a significant difference in melasma area and severity index score of 1.68 for the right side and 2 for the left side (p<0.05). No post-inflammatory hyperpigmentation or rebound was noted. CONCLUSIONS: High-intensity focussed ultrasound combined with toning laser was more effective than Q-switched neodymium-doped yttrium aluminium garnet 1064nm low-fluence laser alone in removing difficult melasma from the malar area in the 2nd, 3rd and 4th sessions, and from the forehead in the 3d and 4th sessions.
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Láseres de Estado Sólido , Melanosis , Humanos , Melanosis/cirugía , Melanosis/terapia , Femenino , Láseres de Estado Sólido/uso terapéutico , Masculino , Adulto , Persona de Mediana Edad , Resultado del Tratamiento , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Terapia por Láser/métodos , Terapia CombinadaRESUMEN
There are still challenges in the preparation of difunctional stereoregular polydienes, especially for the construction of initiating chain-end functionalization. Coordinative chain transfer polymerization (CCTP) provides a way to achieve the goal but usually requires sophisticated functionalized catalysts as well as expensive chain transfer agents (CTAs). In this work, heteroleptic aluminum with oligo(dienyl) substituents (oligo-Al agents) were readily prepared by living anionic polymerization (LAP) technique. The oligo-Al agents used in Nd-mediated CCTPs of dienes exhibit highly selective alkylation and transalkylation features. Kinetics and transfer efficiency studies using 1 H NMR, 13 C NMR, 1 H-13 C HSQC, and Dosy NMR analyses revealed that the resulting polydienes possess substituents at the initiating chain-end that have transferred from the oligo-Al agents. The functionalization efficiency of the initiating chain-end is up to 99 %, and the molar mass regulation efficiency of heteroleptic aluminum is higher than that of the traditional CTA Ali Bu2 H (0.608 vs. 0.410). Based on the experimental results and density functional theory (DFT) calculations, we propose a mechanism in which allylic-Al acts as an efficient alkylating moiety in catalyst preformation and also as an effective transfer agent in polymerization. Taking advantage of these features, di-functionalized polyisoprene, polybutadiene, and poly(isoprene-co-butadiene) can be facilely synthesized.
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Objective: To exploring the regulatory effect of miR-29a on the transforming growth factor-ß1 (TGF-ß1) /Smad homolog 3 (Smad3) pathway during the process of rare earth neodymium oxide (Nd(2)O(3)) induced pulmonary fibrosis in mice. Methods: In March 2021, 72 SPF grade C57/BL6J male mice were selected and randomly divided into a control group, Nd(2)O(3) group, Nd(2)O(3)+miR-29a agomir group, and Nd(2)O(3)+NC agomir group, with 18 mice in each group. The Nd(2)O(3) group, Nd(2)O(3)+miR-29a agomir group, and Nd(2)O(3)+NC agomir group were treated with non exposed tracheal instillation, with a dust concentration of 250 mg/ml and a dust volume of 0.1 ml. The control group was given the same volume of physiological saline. After exposure to Nd(2)O(3), 0.1 ml (5 nmol) of miR-29a agomir was injected into the tail vein of mice in the Nd(2)O(3)+miR-29a agomir group every 3 days, while 0.1 ml of NC agomir was injected into the tail vein of mice in the Nd(2)O(3)+NC agomir group. On the 7 th, 14 th, and 28 th days after dust exposure, 6 mice were killed in each group, and the lung tissue of the mice was taken out. HE staining was used to observe the pathological status of the mouse lung tissue; ELISA method was used to detect the levels of TGF-ß1 and connective tissue growth factor (CTGF) in lung tissue; Use qRT-PCR detection method to detect the expression level of TGF-ß1 mRNA; Using immunofluorescence assay to detect the expression level of Smad3 in mouse lung tissue; Use bioinformatics websites such as TargetScan7 and miRDB to predict the target gene of miR-29a. When the metrological date were satisfied with normal distribution, Mean±SD was used for comparison between groups, t test was used for two indepent samples, and LSD method was used when the variance was homogeneity in pairwise comparison. Results: HE staining showed that the Nd(2)O(3) group of mice showed obvious infiltration of inflammatory cells and structural disorder of alveoli in the early stage of lung tissue. At 28 days, the collagen fibers in the mouse lung tissue increased and the lung tissue showed fibrotic honeycomb like changes. The degree of pulmonary fibrosis in the Nd(2)O(3)+miR-29a agomir group of mice was significantly reduced; The content of TGF-ß1 and CTGF in the lung tissue of mice in the Nd(2)O(3)+miR-29a agomir group was lower than that in the Nd(2)O(3)+NC agomir group (P<0.05) ; The relative expression level of TGF-ß1 in the lung tissue of mice in the Nd(2)O(3)+miR-29a agomir group was lower than that in the Nd(2)O(3)+NC agomir group (P<0.05) ; The expression level of Smad3 in the nucleus of the Nd(2)O(3)+miR-29a agomir group was lower than that of the Nd(2)O(3)+NC agomir group (P<0.05). The prediction results of bioinformatics websites have found 152 downstream target genes related to miR-29a, among which FBN1, MAP2K6, KPNB1, COL1A2, SNIP1, LAMC1, and SP1 genes may be related to the regulatory effect of miR-29a on TGF-ß1/Smad3 signaling pathway. Conclusion: miR-29a may affect lung fibrosis induced by rare earth Nd(2)O(3) exposure in mice by regulating TGF-ß1/Smad3 signaling pathway. Overexpression of miR-29a may inhibit TGF-ß1/Smad3 signaling pathway and reduce the degree of pulmonary fibrosis in mice.
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MicroARNs , Neodimio , Óxidos , Fibrosis Pulmonar , Animales , Masculino , Ratones , Polvo , Fibrosis , MicroARNs/metabolismo , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Proteína smad3/metabolismoRESUMEN
BACKGROUND: Advisability of magnets in neurotrauma is due to pattern of patients admitted to neurosurgical departments of military hospitals with wounds accompanied by intracranial fixation of foreign metallic ferromagnetic bodies. OBJECTIVE: To study dimensions, mass and magnetic properties of fragments extracted from gunshot wounds inflicted by modern weapons; to assess the feasibility of devices and instruments for removing foreign bodies. MATERIAL AND METHODS: We analyzed foreign bodies extracted after gunshot wounds. Shape, dimension, weight and magnetic properties were studied. We estimated 532 foreign bodies (497 surgeries) extracted at the Kirov Military Medical Academy and 83 foreign bodies (79 surgeries) extracted at the Burdenko Military Clinical Hospital. Distribution by anatomical regions was established for both groups. We intraoperatively used cylindrical neodymium magnets 3×20 and 5×20 mm to extract magnetic foreign bodies. These magnets were brought to the target using standard surgical tweezers or original devices. RESULTS: The median mass of removed fragments was 0.385 (Q1-Q3=0.12-1.435; min-max≤0.01-30.5) g at the Kirov Military Medical Academy and 0.4 (Q1-Q3≤0.001-1.6; min-max≤0.01-11.4) g at the Burdenko Military Clinical Hospital. Magnetic foreign bodies were found in 501 (94.2%) and 74 (94.8%) cases, respectively. In 8.8% of cases, foreign bodies were not removed due to difficult-to-reach location accompanied by higher risk of adverse outcomes after extraction. CONCLUSION: Extracted foreign bodies after combat injuries have magnetic properties in 94% of cases. Intraoperative magnet allows for safe extraction of fragments in 91% of cases. Devices with adjustable magnetic field strength seem perspective. Further analysis of indications for removal of wounding projectiles in primary and, especially, repeated surgical treatment of craniocerebral wounds is needed.
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Cuerpos Extraños , Imanes , Heridas por Arma de Fuego , Humanos , Cuerpos Extraños/cirugía , Masculino , Heridas por Arma de Fuego/cirugía , Adulto , FemeninoRESUMEN
A new 3D metal-organic framework (Nd-MOF) {[Nd2L2]·2NH2(CH3)2·3H2O} was successfully established via a solvothermal method with Nd3+ ion and 5-(bis(4-carboxybenzyl) amino)-isophthalicacid (H4L), and has also been characterized by X-ray diffraction, powder X-ray diffraction (PXRD), IR and photoluminescence(PL)spectrum. The neodymium ions are free of coordinated solvents, and the Nd-MOF exhibits strong near-infrared (NIR) fluorescence. Besides, Its NIR fluorescence property shows low temperature resistance, which is favorable for being used in the low temperature environment. Besides, the fluorescence lifetime of Nd-MOF is 6.03 µs, and the quantum yield is 1.2%. The small quantum yield may owe to large energy gap between the T1 of the ligand H4L and the resonance energy level 4F3/2 of the Nd3+ ion, or due to large crystal size of the Nd-MOF.
Asunto(s)
Estructuras Metalorgánicas , Ligandos , Neodimio/química , Difracción de Rayos X , BencilaminasRESUMEN
During the mining of rare earth minerals, the application of neodymium-containing manures, and the treatment of spent neodymium iron boron magnet, the generation of ammonia wastewater containing neodymium is increasing. Thus, the effects of neodymium (Nd(III)) on anaerobic ammonium oxidation (Anammox) were investigated from the aspects of performance, kinetics, statistics, microbial community and sludge morphology, and the recovery strategy of EDTA-2Na wash was discussed. The nitrogen removal efficiency of the Anammox reactor decreased significantly and eventually collapsed at the Nd(III) dosing levels of 20 and 40 mg L-1, respectively. And the toxicity of Nd(III) to AnAOB was determined by the amount internalized into the cells. The EDTA-2Na wash successfully increased the total nitrogen removal rate (TNRR) of Nd(III)-inhibited Anammox to 41.60% of its initial value within 30 days, and the modified Boltzmann model accurately simulated this recovery process. The transient and extended effects of Nd(III), self-recovery, and EDTA-2Na wash on Anammox were effectively assessed using a one-sample t-test. 16S rRNA gene sequencing indicated that Nd(III) remarkably decreased the relative abundance of Planctomycetes and Candidatus Brocadia. The scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) revealed crystal-like neodymium particles on the surface of Anammox sludge. The above-mentioned results demonstrate that the concentration of Nd(III) should be below the toxicity threshold (20 mg L-1) when treating ammonia wastewater containing neodymium by Anammox, and also emphasize the importance of an appropriate recovery strategy.