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1.
J Plant Physiol ; 297: 154262, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38703548

RESUMEN

Aluminum (Al) is the major limiting factor affecting plant productivity in acidic soils. Al3+ ions exhibit increased solubility at a pH below 5, leading to plant root tip toxicity. Alternatively, plants can perceive very low concentrations of Al3+, and Al triggers downstream signaling even at pH 5.7 without causing Al toxicity. The ALUMINUM-ACTIVATED-MALATE-TRANSPORTER (ALMT) family members act as anion channels, with some regulating the secretion of malate from root apices to chelate Al, which is a crucial mechanism for plant Al resistance. To date, the role of the ALMT gene family within the legume Medicago species has not been fully characterized. In this study, we investigated the ALMT gene family in M. sativa and M. truncatula and identified 68 MsALMTs and 18 MtALMTs, respectively. Phylogenetic analysis classified these genes into five clades, and synteny analysis uncovered genuine paralogs and orthologs. The real-time quantitative reverse transcription PCR (qRT-PCR) analysis revealed that MtALMT8, MtALMT9, and MtALMT15 in clade 2-2b are expressed in both roots and root nodules, and MtALMT8 and MtALMT9 are significantly upregulated by Al in root tips. We also observed that MtALMT8 and MtALMT9 can partially restore the Al sensitivity of Atalmt1 in Arabidopsis. Moreover, transcriptome analysis examined the expression patterns of these genes in M. sativa in response to Al at both pH 5.7 and pH 4.6, as well as to protons, and found that Al and protons can independently induce some Al-resistance genes. Overall, our findings indicate that MtALMT8 and MtALMT9 may play a role in Al resistance, and highlight the resemblance between the ALMT genes in Medicago species and those in Arabidopsis.


Asunto(s)
Aluminio , Perfilación de la Expresión Génica , Filogenia , Proteínas de Plantas , Aluminio/toxicidad , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Familia de Multigenes , Medicago truncatula/genética , Medicago truncatula/efectos de los fármacos , Medicago truncatula/metabolismo , Medicago sativa/genética , Medicago sativa/efectos de los fármacos , Medicago sativa/fisiología , Raíces de Plantas/genética , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Genoma de Planta , Transportadores de Anión Orgánico/genética , Transportadores de Anión Orgánico/metabolismo , Medicago/genética , Medicago/fisiología
2.
J Environ Manage ; 359: 120963, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38728980

RESUMEN

An efficient recycling process is developed to recover valuable materials from overhaul slag and reduce its harm to the ecological environment. The high temperature sulfuric acid roasting - water leaching technology is innovatively proposed to prepare Li2CO3 from overhaul slag. Under roasting conditions, fluorine volatilizes into the flue gas with HF, lithium is transformed into NaLi(SO4), aluminum is firstly transformed into NaAl(SO4)2, and then decomposed into Al2O3, so as to selective extraction of lithium. Under the optimal roasting - leaching conditions, the leaching rate of lithium and aluminum are 95.6% and 0.9%, respectively. Then the processes of impurity removal, and settling lithium are carried out. The Li2CO3 with recovery rate of 72.6% and purity of 98.6% could be obtained under the best settling lithium conditions. Compared with the traditional process, this work has short flow, high controllability, remarkable technical, economic, and environmental benefits. This comprehensive recycling technology is suitable for overhaul slag, and has great practical application potential for the disposal of other hazardous wastes in electrolytic aluminum industry.


Asunto(s)
Carbonato de Litio , Reciclaje , Ácidos Sulfúricos , Ácidos Sulfúricos/química , Reciclaje/métodos , Carbonato de Litio/química , Aluminio/química , Litio/química , Agua/química
3.
BMC Oral Health ; 24(1): 581, 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38764034

RESUMEN

BACKGROUND: This study was conducted to compare chemical, elemental and surface properties of sound and carious dentin after application of two restorative materials resin-modified glassionomer claimed to be bioactive and glass hybrid restorative material after enzymatic chemomechanical caries removal (CMCR) agent. METHODS: Forty carious and twenty non-carious human permanent molars were used. Molars were randomly distributed into three main groups: Group 1 (negative control) - sound molars, Group 2 (positive control) - molars were left without caries removal and Group 3 (Test Group) caries excavated with enzymatic based CMCR agent. After caries excavation and restoration application, all specimens were prepared Vickers microhardness test (VHN), for elemental analysis using Energy Dispersive Xray (EDX) mapping and finally chemical analysis using Micro-Raman microscopy. RESULTS: Vickers microhardness values of dentin with the claimed bioactive GIC specimens was statistically higher than with glass hybrid GIC specimens. EDX analysis at the junction estimated: Calcium and Phosphorus of the glass hybrid GIC showed insignificantly higher mean valued than that of the bioactive GIC. Silica and Aluminum mean values at the junction were significantly higher with bioactive GIC specimens than glass hybrid GIC specimen. Micro-raman spectroscopy revealed that bioactive GIC specimens showed higher frequencies of v 1 PO 4, which indicated high level of remineralization. CONCLUSIONS: It was concluded that ion-releasing bioactive resin-based restorative material had increased the microhardness and remineralization rate of carries affected and sound dentin. In addition, enzymatic caries excavation with papain-based CMCR agent has no adverse effect on dentin substrate.


Asunto(s)
Caries Dental , Preparación de la Cavidad Dental , Dentina , Cementos de Ionómero Vítreo , Dureza , Humanos , Caries Dental/terapia , Cementos de Ionómero Vítreo/química , Preparación de la Cavidad Dental/métodos , Fósforo/análisis , Papaína/uso terapéutico , Propiedades de Superficie , Restauración Dental Permanente/métodos , Espectrometría por Rayos X , Espectrometría Raman , Calcio/análisis , Diente Molar , Remineralización Dental/métodos , Aluminio , Dióxido de Silicio , Ensayo de Materiales
4.
Biomed Phys Eng Express ; 10(4)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38744248

RESUMEN

Evaluating neutron output is important to ensure proper dose delivery for patients in boron neutron capture therapy (BNCT). It requires efficient quality assurance (QA) and quality control (QC) while maintaining measurement accuracy. This study investigated the optimal measurement conditions for QA/QC of activation measurements using a high-purity germanium (HP-Ge) detector in an accelerator-based boron neutron capture therapy (AB-BNCT) system employing a lithium target. The QA/QC uncertainty of the activation measurement was evaluated based on counts, reproducibility, and standard radiation source uncertainties. Measurements in a polymethyl methacrylate (PMMA) cylindrical phantom using aluminum-manganese (Al-Mn) foils and aluminum-gold (Al-Au) foils and measurements in a water phantom using gold wire with and without cadmium cover were performed to determine the optimal measurement conditions. The QA/QC uncertainties of the activation measurements were 4.5% for Au and 4.6% for Mn. The optimum irradiation proton charge and measurement time were determined to be 36 C and 900 s for measurements in a PMMA cylindrical phantom, 7.0 C and 900 s for gold wire measurements in a water phantom, and 54 C and 900 s at 0-2.2 cm depth and 3,600 s at deeper depths for gold wire measurements with cadmium cover. Our results serve as a reference for determining measurement conditions when performing QA/QC of activation measurements using HP-Ge detectors at an AB-BNCT employing a lithium target.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Litio , Aceleradores de Partículas , Fantasmas de Imagen , Control de Calidad , Litio/química , Terapia por Captura de Neutrón de Boro/métodos , Humanos , Aceleradores de Partículas/instrumentación , Reproducibilidad de los Resultados , Polimetil Metacrilato/química , Neutrones , Oro/química , Aluminio/química , Agua/química , Radiometría/métodos , Radiometría/instrumentación , Dosificación Radioterapéutica
5.
J Bras Nefrol ; 46(3): e20240023, 2024.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-38748946

RESUMEN

In the last few years, evidence from the Brazilian Registry of Bone Biopsy (REBRABO) has pointed out a high incidence of aluminum (Al) accumulation in the bones of patients with CKD under dialysis. This surprising finding does not appear to be merely a passive metal accumulation, as prospective data from REBRABO suggest that the presence of Al in bone may be independently associated with major adverse cardiovascular events. This information contrasts with the perception of epidemiologic control of this condition around the world. In this opinion paper, we discussed why the diagnosis of Al accumulation in bone is not reported in other parts of the world. We also discuss a range of possibilities to understand why bone Al accumulation still occurs, not as a classical syndrome with systemic signs of intoxication, as occurred it has in the past.


Asunto(s)
Aluminio , Huesos , Humanos , Aluminio/metabolismo , Aluminio/efectos adversos , Huesos/metabolismo , Diálisis Renal , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/complicaciones , Brasil/epidemiología
6.
Lasers Med Sci ; 39(1): 97, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38558189

RESUMEN

To study the effect range of the Nd:YAG laser through various levels of cloudy medium for targets with varying grayscale values in vitro. The coated paper cards with grayscale values of 0, 50, 100, and 150 were used as the laser's targets, which were struck straightly with varying energies using three burst modes (single pulse, double pulse, and triple pulse). Six filters (transmittances of 40, 50, 60, 70, 80, and 90) were applied to simulate various levels of cloudy refractive medium. Image J software was used to measure the diameters and regions of the laser spots. The ranges of the Nd:YAG laser spots increased with energy in the same burst mode (P < 0.05). Under the same amount of energy, the ranges of the Nd:YAG laser spot increased with the grayscale value of the targets (P < 0.05). The greater the transmittance of the filters employed, the larger the range of the Nd: YAG laser spots produced. Assuming that the total pulse energy is identical, the effect ranges of multi-pulse burst modes were significantly larger than those of single-pulse burst mode (P < 0.05). The effect range of a Nd:YAG laser grows with increasing energy and the target's grayscale value. A cloudy refractive medium has a negative impact on the effect range of the Nd: YAG laser. The single pulse mode has the narrowest and safest efficiency range.


Asunto(s)
Aluminio , Láseres de Estado Sólido , Láseres de Estado Sólido/uso terapéutico , Conservación de los Recursos Energéticos , Itrio
7.
Zhonghua Yan Ke Za Zhi ; 60(4): 370-373, 2024 Apr 11.
Artículo en Chino | MEDLINE | ID: mdl-38583061

RESUMEN

A 62-year-old female patient presented with no improvement in vision 10 days after undergoing cataract extraction in the right eye. The unaided visual acuity in the right eye was 0.1, and examination with a slit lamp revealed the presence of the intraocular lens with an increased gap between the intraocular lens and the posterior capsule. Anterior segment optical coherence tomography showed a distance of 3.236 mm between the posterior capsule and the posterior surface of the intraocular lens. Based on the medical history, ocular examination, and auxiliary examinations, a diagnosis of right eye capsular blockage syndrome was made. Nd:YAG laser capsulotomy was performed at the anterior capsule outside the optical zone of the intraocular lens. One week later, the posterior capsule adhered to the posterior surface of the intraocular lens, and there was a significant improvement in vision compared to before the procedure.


Asunto(s)
Terapia por Láser , Láseres de Estado Sólido , Cápsula del Cristalino , Femenino , Humanos , Persona de Mediana Edad , Cápsula del Cristalino/cirugía , Neodimio , Aluminio , Láseres de Estado Sólido/uso terapéutico , Terapia por Láser/métodos , Itrio , Complicaciones Posoperatorias
8.
Urolithiasis ; 52(1): 67, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38630266

RESUMEN

Laser lithotripsy is gaining global prominence and is a dynamically progressing field marked by a continual influx of new and comprehensive research each year. Recently, there has been a noticeable shift toward the adoption of various kinds of lasers, such as holmium: yttrium-aluminum-garnet (Ho:YAG) and thulium fiber (TFL) lasers. Consequently, we aim to conduct a bibliometric analysis to analyze key areas of research activity within scientific publications that center on the utilization of laser techniques in urolithiasis. A search of the literature spanning from 1978 to 2022 was carried out on 25 December 2023 using the Scopus database to explore research related to the application of laser techniques for urolithiasis treatment. Visualization analysis was performed using VOSviewer software (version 1.6.20). We examined 962 publications that met the specified criteria, 791 (82.22%) of which were original articles. The analysis of the retrieved publications indicated a consistent increase in research output from 1978 to 2022; a particularly noteworthy surge occurred after 2003. In particular, the U.S. claimed the leading position as the most productive country, contributing 211 articles (21.93%). However, India had the highest research productivity according to the adjustment index of 19.08. In the European region, 324 publications (33.68% of the total) originated from 25 countries. The Journal of Endourology contributed the most between 1978 and 2022 (n = 96, 9.98%). The most cited paper examined the effectiveness of holmium: yttrium-aluminum-garnet (Ho:YAG) lasers, while a subsequent study focused on the use of a thulium fiber laser (TFL), an emerging laser technology that has gained increased recognition. Co-occurrence analysis revealed three distinct clusters focusing on the types of laser technology, minimally invasive approaches, and success rate/postoperative complications. This comprehensive investigation delves into the global landscape of laser use for the treatment of urolithiasis. This review supports the emerging clinical concept of using various types of laser technology for urolithiasis treatment. Moreover, the hot issues that researchers should focus on based on the findings of this study are the use of different types of laser lithotripsy in view of the surgical approach, success rate and complications.


Asunto(s)
Aluminio , Holmio , Tulio , Itrio , Humanos , Bibliometría , Complicaciones Posoperatorias
9.
Sci Rep ; 14(1): 8836, 2024 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-38632355

RESUMEN

Imidacloprid is still a widely used neonicotinoid insecticide that is banned in many countries because of the associated environmental risks. Due to the inefficiency of conventional wastewater treatments for pesticide removal, new treatment methods are being investigated. Electrochemical methods, including electrocoagulation (EC), seem to be promising alternatives considering their effectiveness in removing various pollutants from wastewater. The aim of this study was to investigate the effects of electrode material, current density, ultrasound, and operation time on the efficiency of imidacloprid removal from a model solution by EC. The combination of aluminum electrodes and 20 A of applied current for 20 min resulted in total imidacloprid degradation. A simplified energy balance was introduced as a form of process evaluation. Combining ultrasound with EC resulted in 7% to 12% greater efficacy than using only EC.


Asunto(s)
Nitrocompuestos , Plaguicidas , Contaminantes Químicos del Agua , Aguas Residuales , Eliminación de Residuos Líquidos/métodos , Neonicotinoides , Electrocoagulación , Electrodos , Aluminio
10.
Int J Mol Sci ; 25(7)2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38612522

RESUMEN

The multidrug and toxic compound extrusion (MATE) proteins are coding by a secondary transporter gene family, and have been identified to participate in the modulation of organic acid exudation for aluminum (Al) resistance. The soybean variety Glycine max "Tamba" (TBS) exhibits high Al tolerance. The expression patterns of MATE genes in response to Al stress in TBS and their specific functions in the context of Al stress remain elusive. In this study, 124 MATE genes were identified from the soybean genome. The RNA-Seq results revealed significant upregulation of GmMATE13 and GmMATE75 in TBS upon exposure to high-dose Al3+ treatment and both genes demonstrated sequence homology to citrate transporters of other plants. Subcellular localization showed that both proteins were located in the cell membrane. Transgenic complementation experiments of Arabidopsis mutants, atmate, with GmMATE13 or GmMATE75 genes enhanced the Al tolerance of the plant due to citrate secretion. Taken together, this study identified GmMATE13 and GmMATE75 as citrate transporter genes in TBS, which could improve citrate secretion and enhance Al tolerance. Our findings provide genetic resources for the development of plant varieties that are resistant to Al toxicity.


Asunto(s)
Aluminio , Arabidopsis , Aluminio/toxicidad , Glycine max/genética , Arabidopsis/genética , Membrana Celular , Citratos
11.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38612669

RESUMEN

The multidrug and toxin efflux (MATE) family participates in numerous biological processes and plays important roles in abiotic stress responses. However, information about the MATE family genes in Torreya grandis remains unclear. In this study, our genome-wide investigation identified ninety MATE genes in Torreya grandis, which were divided into five evolutionary clades. TgMATE family members are located on eleven chromosomes, and a total of thirty TgMATEs exist in tandem duplication. The promoter analysis showed that most TgMATEs contain the cis-regulatory elements associated with stress and hormonal responses. In addition, we discovered that most TgMATE genes responded to abiotic stresses (aluminum, drought, high temperatures, and low temperatures). Weighted correlation network analysis showed that 147 candidate transcription factor genes regulated the expression of 14 TgMATE genes, and it was verified through a double-luciferase assay. Overall, our findings offer valuable information for the characterization of the TgMATE gene mechanism in responding to abiotic stress and exhibit promising prospects for the stress tolerance breeding of Torreya grandis.


Asunto(s)
Taxaceae , Toxinas Biológicas , Fitomejoramiento , Aluminio , Bioensayo , Estrés Fisiológico/genética
12.
Nutrients ; 16(7)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38613056

RESUMEN

Aluminum contamination in parenteral nutrition (PN) solutions can lead to neurotoxicity, reduced bone mass, and liver toxicity, especially in pediatric patients. Ingredients commonly used in PN compounding, such as vitamins, trace elements, calcium, and phosphate salts, contain significant amounts of aluminum. This study aimed to compare aluminum concentrations in multichamber-bag (MCB) and compounded PN for adults and pediatrics. A prospective study assessed aluminum concentrations in various types of MCB and compared them with compounded PN formulations with similar compositions. The types of MCB included Lipoflex® (without electrolytes), Omegaflex®, Finomel®, Smofkabiven® (with and without electrolytes), Olimel®, Clinimix®, and Numeta®. Overall, 80 aluminum determinations were included: 36 for MCBs and 44 for compounded PN. MCBs showed significantly lower aluminum concentrations than compounded PN: 11.37 (SD 6.16) vs. 21.45 (8.08) µg/L, respectively. Similar results were observed for adult (n = 40) and pediatric (n = 40) PN formulations (12.97 (7.74) vs. 20.78 (10.28) µg/L, and 9.38 (2.23) vs. 22.01 (5.82) µg/L, respectively). Significant differences were also found between MCBs depending on the manufacturing company. These findings suggest that MCBs PN offer a safer option for reducing aluminum contamination in PN. Harmonizing regulations concerning aluminum concentrations in PN solutions could help mitigate differences between PN formulations.


Asunto(s)
Aluminio , Nutrición Parenteral , Adulto , Humanos , Niño , Estudios Prospectivos , Soluciones para Nutrición Parenteral , Electrólitos
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 314: 124221, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38569390

RESUMEN

The toxicological effect between co-existed antibiotics and metal ions was dangerous to the ecological environment and public health. However, the rapid quantification tools with convenience, accuracy and low cost for the detection of multiple targets were still challenging. Herein, a portable tri-color ratiometric fluorescence paper sensor was constructed by coupling of blue carbon dots and fluorescence imprinted polymer for down/up conversion simultaneous detection of tetracycline and sulfamethazine. Interestingly, the cascade detection of aluminum ion was also realized based on the individual detection system of tetracycline without the assistance of complex coupling reagents. The detection limits of smartphone method for the visual detection of tetracycline, sulfamethazine and aluminum ion were calculated as 0.014 µM, 0.004 µM and 0.019 µM, respectively. The portable fluorescence paper sensor was applied for the visual detection of tetracycline, sulfamethazine and aluminum ion in actual samples successfully with satisfactory recoveries. With the advantages of rapidness, low cost, and portability, the developed portable fluorescence paper sensor provided a new strategy for the visual real-time detection of multiple targets.


Asunto(s)
Antibacterianos , Puntos Cuánticos , Aluminio , Sulfametazina , Fluorescencia , Tetraciclina , Carbono , Iones , Colorantes Fluorescentes , Espectrometría de Fluorescencia , Límite de Detección
14.
BMC Oral Health ; 24(1): 444, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609958

RESUMEN

BACKGROUND: This study evaluated the shear bond strength (SBS) of two different polyetheretherketone (PEEK) and CAD-CAM materials after aging. METHODS: A total of 42 frameworks were designed and milled from 2 different PEEK discs (Copra Peek, P and BioHPP, B). P and B frameworks were divided into 3 subgroups (n = 7). 14 slices were prepared each from feldspathic ceramic (Vitablocs Mark II, VM), hybrid nanoceramic (Cerasmart, CS), and polymer-infiltrated ceramic (Vita Enamic, VE) blocks. After surface preparations, the slices were cemented to P and B surfaces. The samples were subjected to thermal aging (5000 cycles). SBS of all the samples was measured. Fractured surfaces were examined by SEM/EDX analysis. The Shapiro-Wilk, Two-way Robust ANOVA and Bonferroni correction tests were used to analyze the data (a = .05). RESULTS: Frameworks, ceramics, and frameworks x ceramics had significant differences (p < 0.05). The highest SBS value was seen in B-VM (p < 0.05). VM offered the highest SBS with both P and B. The differences between P-VM, P-CS, P-VE and B-CS and B-VE were insignificant (p > 0.05). According to EDX analysis, ytterbium and fluorine was seen in B content, unlike P. While VM and CS contained fluorine, barium, and aluminum; sodium and aluminum were observed in the VE structure. CONCLUSION: Bonding of P and B with VM offers higher SBS. VM, CS and VE did not make any difference in SBS for P, however VM showed a significant difference for B.


Asunto(s)
Aluminio , Benzofenonas , Flúor , Polímeros , Humanos , Polietilenglicoles , Diseño Asistido por Computadora , Cetonas
15.
Water Sci Technol ; 89(7): 1879-1890, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38619909

RESUMEN

This study investigated the treatment of wastewater from tomato paste (TP) production using electrocoagulation (EC) and electrooxidation (EO). The effectiveness of water recovery from the pretreated water was then investigated using the membrane process. For this purpose, the effects of independent control variables, including electrode type (aluminum, iron, graphite, and stainless steel), current density (25-75 A/m2), and electrolysis time (15-120 min) on chemical oxygen demand (COD) and color removal were investigated. The results showed that 81.0% of COD and 100% of the color removal were achieved by EC at a current density of 75 A/m2, a pH of 6.84 and a reaction time of 120 min aluminum electrodes. In comparison, EO with graphite electrodes achieved 55.6% of COD and 100% of the color removal under similar conditions. The operating cost was calculated to be in the range of $0.56-30.62/m3. Overall, the results indicate that EO with graphite electrodes is a promising pretreatment process for the removal of various organics. In the membrane process, NP030, NP010, and NF90 membranes were used at a volume of 250 mL and 5 bar. A significant COD removal rate of 94% was achieved with the membrane. The combination of EC and the membrane process demonstrated the feasibility of water recovery from TP wastewater.


Asunto(s)
Grafito , Solanum lycopersicum , Contaminantes Químicos del Agua , Aguas Residuales , Eliminación de Residuos Líquidos/métodos , Aluminio , Electrocoagulación/métodos , Agua , Electrodos , Residuos Industriales/análisis
16.
Water Res ; 256: 121539, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38583335

RESUMEN

Inorganic coagulants such as poly aluminum ferric chloride (Al/Fe) are applied conventionally to sewage sludge dewatering and can be retained in the sludge cake, causing its conductivity to increase and generate secondary pollution. To reduce these disadvantages, there is a need to develop alternative, more sustainable chemicals as substitutes for conventional inorganic coagulants. In the present investigation, the application of a polymeric chitosan quaternary ammonium salt (CQAS) is explored as a complete, or partial, replacement for Al/Fe in the context of sludge dewatering processes. Laboratory experiments using digested sewage sludge showed that CQAS could effectively substitute for over 80 % of the Al/Fe inorganic coagulant in the sludge dewatering process. This substitution resulted in a reduction of sludge cake conductivity by more than 50 %. Simulation of sludge dewatering curves and imaging of the sludge surface indicated that the addition of CQAS led to an increase in nanosized pores, and a decrease in the specific resistance of the sludge filter cake as the dosage of Al/Fe decreased to around 30 %. The variations of fluorescence emission, quantum yield and carboxylic and amino groups, suggested that the chelating of Al/Fe decreased due to the bridging effects of CQAS. The CQAS had different flocculation bridging effects on various EPS fractions, which varied the amount of protein chelated with Al/Fe in each fraction. This study provides new information about the benefits of replacing conventional inorganic coagulants with natural organic polymers for sewage sludge dewatering, in terms of reduced sludge cake conductivity and greater dry solids content.


Asunto(s)
Quitosano , Compuestos Férricos , Aguas del Alcantarillado , Aguas del Alcantarillado/química , Quitosano/química , Compuestos Férricos/química , Compuestos de Amonio Cuaternario/química , Floculación , Cloruros/química , Eliminación de Residuos Líquidos/métodos , Aluminio/química
17.
Waste Manag ; 182: 11-20, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38626501

RESUMEN

Recycling aluminium in a rotary furnace with salt-fluxes allows recovering valuable alloys from hard-to-recycle waste/side-streams such as packaging, dross and incinerator bottom ash. However, this recycling route generates large amounts of salt-slag/salt-cake hazardous wastes which can pose critical environmental risks if landfilled. To tackle this issue, the metallurgical industry has developed processes to valorise the salt-slag residues into recyclable salts and aluminium concentrates, while producing by-products such as ammonium sulphate and non-metallic compounds (NMCs), with applications in the construction or chemical industries. This study aims to assess through LCA the environmental impacts of recycling aluminium in rotary furnaces for both salt-slag management routes: valorisation or landfill. It was found that this recycling process brings forth considerable net environmental profits, which increase for all the considered impact categories if the salt-slag is valorised. The main benefits arise from the production of secondary cast aluminium alloys, which is not unexpected due to the high energy intensity of aluminium primary production. However, the LCA results also identify other hotspots which play a significant role, and which should be considered for the optimisation of the process based on its environmental performance, such as the production of by-products, the consumption of energy/fuels and the avoidance of landfilling waste. Additionally, the assessment shows that the indicators for mineral resource scarcity, human carcinogenic toxicity and terrestrial ecotoxicity are particularly benefited by the salt-slag valorisation. Finally, a sensitivity analysis illustrates the criticality of the metal yield assumptions when calculating the global warming potential of aluminium recycling routes.


Asunto(s)
Aluminio , Incineración , Reciclaje , Incineración/métodos , Reciclaje/métodos , Aluminio/química , Aluminio/análisis , Ambiente , Residuos Industriales/análisis , Metalurgia
18.
Plant Physiol Biochem ; 210: 108626, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38615443

RESUMEN

Stomatal operation is crucial for optimising plant water and gas exchange and represents a major trait conferring abiotic stress tolerance in plants. About 56% of agricultural land around the globe is classified as acidic, and Al toxicity is a major limiting factor affecting plant performance in such soils. While most of the research work in the field discusses the impact of major abiotic stresses such as drought or salinity on stomatal operation, the impact of toxic metals and, specifically aluminium (Al) on stomatal operation receives much less attention. We aim to fill this knowledge gap by summarizing the current knowledge of the adverse effects of acid soils on plant stomatal development and operation. We summarised the knowledge of stomatal responses to both long-term and transient Al exposure, explored molecular mechanisms underlying plant adaptations to Al toxicity, and elucidated regulatory networks that alleviate Al toxicity. It is shown that Al-induced stomatal closure involves regulations of core stomatal signalling components, such as ROS, NO, and CO2 and key elements of ABA signalling. We also discuss possible targets and pathway to modify stomatal operation in plants grown in acid soils thus reducing the impact of Al toxicity on plant growth and yield.


Asunto(s)
Aluminio , Estomas de Plantas , Suelo , Aluminio/toxicidad , Estomas de Plantas/efectos de los fármacos , Estomas de Plantas/fisiología , Suelo/química , Productos Agrícolas/metabolismo , Productos Agrícolas/efectos de los fármacos , Productos Agrícolas/crecimiento & desarrollo , Adaptación Fisiológica/efectos de los fármacos
19.
Chemosphere ; 357: 141981, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38626813

RESUMEN

Metal-Organic Frameworks (MOFs) are extensively used as electrode material in various sensing applications due to their efficacious porous nature and tunable properties. However, pristine MOFs lack conductive attributes that hinder their wide usage in electrochemical applications. Electropolymerization of several aromatic monomers has been a widely used strategy for preparing conducting electrode materials for various sensing applications in the past decades. Herein, we report a similar approach by employing the electropolymerization method to create a functional polymer layer to enhance the sensitivity of an Aluminium Organic Framework (DUT-4) for the selective detection of Chloramphenicol (CAP) antibiotic in aqueous environment. The combined strategy using the conducting polymer layer with the porous Al MOF provides surpassing electrochemical performance for sensing CAP with regard to the very low detection limit (LOD = 39 nM) and exceptionally high sensitivity (11943 µA mM-1 cm-2). In addition, the fabricated sensor exhibited good selectivity, reproducibility and stability. The developed method was successfully evaluated in various real samples including lake water and river water for CAP detection with good recovery percentages even at lower concentrations.


Asunto(s)
Aluminio , Cloranfenicol , Técnicas Electroquímicas , Límite de Detección , Estructuras Metalorgánicas , Polímeros , Contaminantes Químicos del Agua , Cloranfenicol/análisis , Estructuras Metalorgánicas/química , Contaminantes Químicos del Agua/análisis , Aluminio/análisis , Aluminio/química , Polímeros/química , Técnicas Electroquímicas/métodos , Reproducibilidad de los Resultados , Antibacterianos/análisis , Electrodos , Ríos/química , Lagos/química , Lagos/análisis
20.
ACS Biomater Sci Eng ; 10(5): 3438-3453, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38564666

RESUMEN

Despite being a weaker metal, zinc has become an increasingly popular candidate for biodegradable implant applications due to its suitable corrosion rate and biocompatibility. Previous studies have experimented with various alloy elements to improve the overall mechanical performance of pure Zn without compromising the corrosion performance and biocompatibility; however, the thermal stability of biodegradable Zn alloys has not been widely studied. In this study, TiC nanoparticles were introduced for the first time to a Zn-Al-Cu system. After hot rolling, TiC nanoparticles were uniformly distributed in the Zn matrix and effectively enabled phase control during solidification. The Zn-Cu phase, which was elongated and sharp in the reference alloy, became globular in the nanocomposite. The strength of the alloy, after introducing TiC nanoparticles, increased by 31% from 259.7 to 340.3 MPa, while its ductility remained high at 49.2% elongation to failure. Fatigue performance also improved greatly by adding TiC nanoparticles, increasing the fatigue limit by 47.6% from 44.7 to 66 MPa. Furthermore, TiC nanoparticles displayed excellent phase control capability during body-temperature aging. Without TiC restriction, Zn-Cu phases evolved into dendritic morphologies, and the Al-rich eutectic grew thicker at grain boundaries. However, both Zn-Cu and Al-rich eutectic phases remained relatively unchanged in shape and size in the nanocomposite. A combination of exceptional tensile properties, improved fatigue performance, better long-term stability with a suitable corrosion rate, and excellent biocompatibility makes this new Zn-Al-Cu-TiC material a promising candidate for biodegradable stents and other biodegradable applications.


Asunto(s)
Implantes Absorbibles , Cobre , Stents , Zinc , Zinc/química , Zinc/farmacología , Cobre/química , Cobre/farmacología , Aleaciones/química , Humanos , Titanio/química , Titanio/farmacología , Aluminio/química , Aluminio/farmacología , Ensayo de Materiales , Corrosión , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Nanopartículas del Metal/química , Nanopartículas del Metal/uso terapéutico , Nanopartículas/química , Nanocompuestos/química
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