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Patients with symptomatic intracranial arterial stenosis (sICAS) suffer embarrassed hemodynamic status and acute ischemic stroke (AIS) recurrence. We aimed to assess the efficacy of remote ischemic conditioning (RIC) on improving this status by evaluating cerebral blood flow (CBF) and cerebral glucose metabolism (CGM) via PET/CT. Adult patients with unilateral sICAS in middle cerebral artery and/or intracranial segment of internal carotid artery-related AIS or transient ischemic attack within 6 months prior to randomization were enrolled. Individuals who received intravenous thrombolysis or endovascular treatment, or sICAS caused by cardiac embolism, small vessel occlusion, or other determined causes were excluded. Twenty-three eligible patients were randomly assigned to standard medical treatment (SMT) (n = 10) or RIC group (n = 13). The RIC protocol consisted of 5 cycles, each for 5-min bilateral upper limb ischemia and 5-min reperfusion period, twice a day, with a total duration of 3 months. Ten healthy volunteers were enrolled as healthy control group. We tested CBF and CGM at the rest stage and the methazolamide-induced stress stage. All patients received PET/CT at baseline and three-month followup. Both CBF and CGM in ipsilateral hemisphere of sICAS patients were significantly decreased at the rest stage and the stress stage (p < .05), which were improved by three-month RIC (p < .05). The lesions decreased notably in RIC group compared to SMT group (p < .05). RIC ameliorated the hemodynamic status and glucose metabolism in regions at high risk of infarction, which might improve the resistance capacity towards ischemic load in sICAS patients.
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Arteriosclerosis Intracraneal , Accidente Cerebrovascular Isquémico , Adulto , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones , Arteriosclerosis Intracraneal/diagnóstico por imagen , Arteriosclerosis Intracraneal/terapia , Isquemia , Hemodinámica , GlucosaRESUMEN
Electrochemically converting nitrate, a widely distributed nitrogen contaminant, into harmless N2 is a feasible and environmentally friendly route to close the anthropogenic nitrogen-based cycle. However, it is currently hindered by sluggish kinetics and low N2 selectivity, as well as scarce attention to reactor configuration. Here, we report a flow-through zero-gap electrochemical reactor that shows a high performance of nitrate reduction with 100% conversion and 80.36% selectivity of desired N2 in the chlorine-free system at 100 mg-N·L-1 NO3- while maintaining a rapid reduction kinetics of 0.07676 min-1. More importantly, the mass transport and current utilization efficiency are significantly improved by shortening the inter-electrode distance, especially in the zero-gap electrocatalytic system where the current efficiency reached 50.15% at 5 mA·cm-2. Detailed characterizations demonstrated that during the electroreduction process, partial Cu(OH)2 on the cathode surface was reconstructed into stable Cu/Cu2O as the active phase for efficient nitrate reduction. In situ characterizations revealed that the highly selective *NO to *N conversion and the N-N coupling step played crucial roles during the selective reduction of NO3- to N2 in the zero-gap electrochemical system. In addition, theoretical calculations demonstrated that improving the key intermediate *N coverage could effectively facilitate the N-N coupling step, thereby promoting N2 selectivity. Moreover, the environmental and economic benefits and long-term stability shown by the treatment of real nitrate-containing wastewater make our proposed electrocatalytic system more attractive for practical applications.
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Nitratos , Aguas Residuales , Nitratos/química , Electrodos , Nitrógeno/análisis , Nitrógeno/química , CinéticaRESUMEN
The photochemical behavior of organic pollutants in ice is poorly studied in comparison to aqueous photochemistry. Here we report a detailed comparison of ice and aqueous photodegradation of two representative OH-PAHs, 2-hydroxyfluorene (2-OHFL) and 9-hydroxyfluorene (9-OHFL), which are newly recognized contaminants in the wider environment including colder regions. Interestingly, their photodegradation kinetics were clearly influenced by whether they reside in ice or water. Under the same simulated solar irradiation (λ > 290 nm), OHFLs photodegraded faster in ice than in equivalent aqueous solutions and this was attributed to the specific concentration effect caused by freezing. Furthermore, the presence of dissolved constituents in ice also influenced photodegradation with 2-OHFL phototransforming the fastest in 'seawater' ice (k = (11.4 ± 1.0) × 10-2 min-1) followed by 'pure-water' ice ((8.7 ± 0.4) × 10-2 min-1) and 'freshwater' ice ((8.0 ± 0.7) × 10-2 min-1). The presence of dissolved constituents (specifically Cl-, NO3-, Fe(III) and humic acid) influences the phototransformation kinetics, either enhancing or suppressing phototransformation, but this is based on the quantity of the constituent present in the matrixes, the specific OHFL isomer and the matrix type (e.g., ice or aqueous solution). Careful derivation of key photointermediates was undertaken in both ice and water samples using tandem mass spectrometry. Ice phototransformation exhibited fewer by-products and 'simpler' pathways giving rise to a range of hydroxylated fluorenes and hydroxylated fluorenones in ice. These results are of importance when considering the fate of PAHs and OH-PAHs in cold regions and their persistence in sunlit ice.
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Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Compuestos Férricos , Fluorenos/análisis , Sustancias Húmicas/análisis , Hielo/análisis , Cinética , Fotólisis , Hidrocarburos Policíclicos Aromáticos/análisis , Agua/química , Contaminantes Químicos del Agua/análisisRESUMEN
C-N bond formation takes on a critical significance in reactions of organic synthesis, material production and pharmaceutical manufactory. Chan-Lam has proposed a useful methodology to furnish secondary arylamides under mild conditions. However, when chiral sulfinamides serve as the coupling precursors, the Cu-catalyzed coupling reaction is found with low efficacy. Complex side-products are generated under classic conditions. Moreover, it led to the racemization of the coupling product. In this study, an optimized Ni-catalyzed Chan-Lam type coupling conditions were proposed, which resulted in clean conversion from chiral sulfinamides and arylboronic acids to offer N-aryl sulfinamides efficiently and enantioretentively. The trans-N1 ,N2 -dimethylcyclohexane-1,2-diamine was proven as the most efficient ligand. Under the optimized conditions, a series of chiral N-aryl sulfinamides was prepared with high chemical yield without racemization. Furthermore, a plausible and novel mechanism was proposed. Interestingly, the method could efficiently furnish a wide variety of C-X bonds by coupling arylboronic acids with different nucleophiles.
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Catálisis , Técnicas de Química Sintética , LigandosRESUMEN
Chromium (Cr) is mainly found in the form of organic-Cr(III) complexes in the natural environment and industrial waste. The widespread existence of composite contaminants composed of organic matter (OM) and Cr pose a serious ecological threat, and its potential interaction and removal need to be further summarised. Organic ligands, such as carbohydrates, nitrogen compounds, phenolic compounds, humus substances (HS), and low molecular weight organic acids (LMWOAs), play an important role in governing the speciation, mobility, and absorption and desorption of Cr in the environment. Moreover, growing evidence indicates that oxygen-containing functional groups (e.g., carboxyl, hydroxyl, and phosphate) are closely related to the complexation of Cr(III). Advanced oxidation processes (AOPs) are efficient and widely applicable technologies. However, the re-complexation of oxidation intermediates with Cr(III) and the formation and accumulation of much more toxic Cr(VI) species hinder the possible utilisation of AOPs. In this paper, the sources and harmful effects of organic-Cr(III) complexes are reported in detail. The complexation behaviour and structure of the organic-Cr(III) complexes are also described. Subsequently, the application of AOPs in the decomplexation and degradation of organic-Cr(III) complexes is summarised. This review can be helpful for developing technologies that are more efficient for organic-Cr(III) complex removal and establishing the scientific background for reducing Cr discharge Cr into the environment.
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Cromo , Residuos Industriales , Cromo/química , Radical Hidroxilo , Compuestos Orgánicos , Oxidación-ReducciónRESUMEN
As a hazardous waste, the disposal of chromium enriched tannery sludge has attracted increasing public concern due to its potential adverse risks towards the environment. And incineration is considered to be an effective method to stabilize heavy metals, like Cr, in solid phase during tannery sludge treatment. In this study, real chromium enriched tannery sludge without pre-treatment was incinerated at 300°C-1200 °C under air atmosphere to investigate the transformation of chromium speciation. Here detailed thermal behavior, phase transformation and chromium speciation were characterized by TG-DSC, XRD and XPS, respectively. Experimental results show that content of Cr(VI) increases gradually with the increase of temperature from 300 °C to 500 °C and reaches a maximal level of 46% total Cr at 500 °C, with different Cr(VI) species of CaCrO4, MgCrO4 and Cr5O12. However, the content of Cr(VI) decreases gradually with the further increase of temperature, with only about 5% Cr(VI) at high temperature of 1200 °C, due to formation of Cr(III) species of Cr2O3 crystallite and MgCr2O4 spinel. Besides, a growing number of hexagonally shaped flake-like crystallite Cr2O3 can be discovered from characterization results of XRD and SEM. Finally, the reduction of CaCrO4 to Cr2O3 in the presence of SiO2 is thermodynamically feasible over 700 °C, indicating possible transformation of Cr(VI) to Cr(III) through controlled incineration temperature.
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Incineración , Residuos Industriales , Aguas del Alcantarillado , Cromo , Dióxido de Silicio , TemperaturaRESUMEN
In this paper, a process combining biodegradation and Fenton oxidation was proposed for the removal of polydiallyldimethylammonium chloride-acrylic-acrylamide-hydroxyethyl acrylate (PDM) in aqueous phase. Biodegradation of PDM was investigated in activated sludge systems, and the effects of the solution pH, mixed liquid suspended solids (MLSS), salinity, co-substrate, and initial substrate concentration, were studied. The biodegradation process was well-described with the Monod model and the values of the kinetics parameters vmax, ks were 0.05 h-1 and 333â¯mg/L. The optimal biodegradation conditions in the experimental range were determined to be: pHâ¯=â¯7.0, 0%-0.01% (w/v) NaCl, 4000â¯mg/L of MLSS, and 500â¯mg/L of glucose as co-substrate. FT-IR analysis indicated that PDM molecules biodegradation partly. The microbial community structures and dehydrogenase activity analysis revealed that PDM showed some toxicity to microorganisms in activated sludge. The effects of several parameters, including the pH and chemical doses, were investigated for removing PDM in Fenton oxidation process. The optimal Fenton oxidation process conditions in the experimental range were pHâ¯=â¯2.0, Fe2+ concentration of 40â¯mg/L, and H2O2 dosage of 23â¯mL/L. PDM was treated by biodegradation and subsequent Fenton oxidation under the optimal operating conditions. The removal efficiency was 44.5% after the biodegradation process and further increased to 85.5% after Fenton oxidation. The combined process was revealed to be a promising solution for achieving effective and economical removal of PDM.
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Peróxido de Hidrógeno/química , Hierro/química , Polietilenos/análisis , Compuestos de Amonio Cuaternario/análisis , Aguas del Alcantarillado , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Adsorción , Biodegradación Ambiental , Cinética , Oxidación-Reducción , Aguas del Alcantarillado/química , Aguas del Alcantarillado/microbiologíaRESUMEN
Wastewater from printing and dyeing processes often contains aniline and high salinity, which are hazardous to aquatic species. Glycophytic plants cannot survive under high-salinity conditions, whereas halophytes grow well in such an environment. In this study, we investigated the influence of NaCl on the antioxidant level in Suaeda salsa affected by aniline stress. The seedlings showed various growth toxicity effects under different concentrations of aniline. The results showed that the effect of the aniline was more severe for the root growth compared to that for the shoot growth. Aniline exposure significantly increased the total free radicals and ·OH radicals in the plants. Suaeda salsa exposure to aniline caused oxidative stress by altering the superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) activity, which resulted in the overproduction of H2O2 and the inducement of lipid peroxidation. Analysis revealed that the malondialdehyde (MDA) content was enhanced after aniline exposure and that the chlorophyll content was significantly decreased. The results showed that aniline induced the production of free radicals and reactive oxygen species (ROS), and changed the antioxidant defense system. This ultimately resulted in oxidative damage in S. salsa; however, it was found that moderate salinity could mitigate the effects. In conclusion, salinity may alleviate the growth inhibition caused by aniline by regulating the antioxidant capacity of S. salsa.
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Compuestos de Anilina/toxicidad , Antioxidantes/metabolismo , Chenopodiaceae/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Cloruro de Sodio/farmacología , Contaminantes Químicos del Agua/toxicidad , Catalasa/metabolismo , Chenopodiaceae/enzimología , Chenopodiaceae/crecimiento & desarrollo , Clorofila/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Peróxido de Hidrógeno/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Malondialdehído/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Salinidad , Plantas Tolerantes a la Sal/efectos de los fármacos , Plantas Tolerantes a la Sal/enzimología , Plantas Tolerantes a la Sal/crecimiento & desarrollo , Plantones/efectos de los fármacos , Plantones/enzimología , Plantones/crecimiento & desarrollo , Superóxido Dismutasa/metabolismoRESUMEN
Graphene Oxide (GO) has wide applications in many fields which has caused a large expected quantity of the graphene-based wastes. It is necessary to understand the toxic effects of the GO on the activated sludge (AS) considering its inevitable discharge to the wastewater treatment plants as the ultimate repositories for these wastes. In this study, the acute exposures of the multilayer Nano-graphene oxide (MNGO) at different dosages were conducted in order to investigate its integrated effects on the formation of the biofilm, mature biofilm and the microbial activity of the activated sludge. Raman spectroscopy and laser scanning confocal microscopy (LSCM) were adopted for the in-situ characterization of the biofilm with the exposure of the MNGO. The results showed that the activated sludge was tolerable to the acute exposure of the less than 100 mg/L of the MNGO, especially for the mature biofilm, and only a subtle decrease was found in the size and thickness during the formation of the biofilm, while the amount of 300 mg/L of the MNGO caused the sever deterioration on the activated sludge system. The microbial metabolic activity, viability, and the biological removal of the nutrients were significantly affected with the more than 100 mg/L of the MNGO. It was also demonstrated by the microbial cytotoxicity tests that the increase in the exposure of the MNGO was related to the increase in the reactive oxygen species (ROS) and the damaging degree of the cell membrane.
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Biopelículas/efectos de los fármacos , Grafito/toxicidad , Viabilidad Microbiana/efectos de los fármacos , Aguas del Alcantarillado/microbiología , Aguas Residuales/microbiología , Contaminantes Químicos del Agua/toxicidad , China , Especies Reactivas de Oxígeno/metabolismo , Aguas del Alcantarillado/química , Aguas Residuales/química , Purificación del Agua/métodosRESUMEN
Due to their assembly properties and variable molecular weights, the potential biological toxicity effects of macromolecular organic ligand heavy metal complexes are more difficult to predict and their mechanisms are more complex. This study unraveled the toxicity response and metabolic compensation mechanism of tannic acid-Cr(III) (TA-Cr(III)) complex on alga Raphidocelis subcapitata using multi-omics approaches. Results showed TA-Cr(III) complex caused oxidative damage and photosystem disruption, destroying the cell morphology and inhibiting algal growth by >80 % at high exposure levels. TA-Cr(III) complex stress down-regulated proteins linked to proliferation, photosynthesis and antioxidation while upregulating carbon fixation, TCA cycle and amino acid metabolism. The increase of fumarate, citrate, isocitrate and semialdehyde succinate was validated by metabolomics analysis, which improved the TCA cycle, amino acid metabolism and carbon fixation. Activation of the above cellular processes somewhat compensated for the inhibition of algal photosynthesis by TA-Cr(III) complex exposure. In conclusion, physiological toxicity coupled with downstream metabolic compensation in response to Cr(III) complex of macromolecular was characterized in Raphidocelis subcapitata, unveiling the adaptive mechanism of algae under the stress of heavy metal complexes with macromolecular organic ligands.
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Taninos , Cromo/toxicidad , Fotosíntesis/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , PolifenolesRESUMEN
The severe negative effects of impurities adhering to the external surface of wearable devices can significantly influence the signal transmission, performance, and lifespan of hydrogel sensors. Herein, we developed an ion-conducting hydrogel sensor with a strong adhesive side and a non-adhesive side, similar to a "semi-releasing material." This hydrogel, formulated using deep eutectic solvents obtained from choline chloride and acrylic acid, contained lignin. This versatile material, exhibiting properties similar to semi-releasing materials, was treated with an AlCl3 solution on one side. Additionally, the hydrogel was successfully used as a highly adhesive strain sensor for real-time monitoring of various human activity signals. Moreover, the hydrogel demonstrated excellent environmental tolerance and conductivity. Lignin extracted from wood flour endowed the hydrogel sensor with excellent adhesion energy (up to 427.1 J/m2) and UV resistance. Treatment of hydrogels with AlCl3 completely eliminated their adhesiveness, thereby enhancing fracture elongation and tensile strength. This improvement can be attributed to the absence of carboxyl groups and the formation of a metal-phenolic network. The implementation of this convenient and efficient strategy provides a more feasible approach to address challenges related to impurity adhesion and signal transmission in flexible wearable devices.
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Hidrogeles , Lignina , Dispositivos Electrónicos Vestibles , Lignina/química , Hidrogeles/química , Humanos , Conductividad Eléctrica , Resistencia a la Tracción , Cloruro de Aluminio/química , Iones/químicaRESUMEN
BACKGROUND: The efficacy and safety of dabigatran etexilate for Chinese patients with cerebral venous thrombosis (CVT) has not been well established. METHODS: CHOICE-CVT was an exploratory, single-center, randomized, open-label study in the National Center for Neurological Disorders involving Chinese patients with CVT aged 18 to 80 years who were randomly assigned (1:1) to either dabigatran etexilate or warfarin. Oral anticoagulants were initiated after 10-15 days of LMWH. The primary efficacy and safety endpoints included the number of patients with recurrent CVT and/or deep venous thrombosis (DVT) and major clinical bleeding within 180 days. Secondary efficacy endpoints included venous recanalization and change in papilledema at day 180. Secondary safety outcomes comprised death, clinical nonmajor bleeding, and any bleeding. The study was registered with ClinicalTrials.gov under NCT03930940. RESULTS: Between October 2017 and February 2023, a total of 89 patients were enrolled and randomly assigned to receive either dabigatran etexilate (n = 44) or warfarin (n = 45). At day 180, the dabigatran etexilate group showed a statistically nonsignificant but likely clinically significant number of patients with recurrent CVT and/or DVT (8 (18.2%; 95% CI, 6.3-30.0) vs 3 (6.7%; 95% CI, 0.0-14.2), p = 0.099, with a power (1-ß) of 38.401%) compared with the warfarin group. The dabigatran etexilate group showed a comparable number of patients with clinical major bleeding (0 (0) vs 0 (0) p = 1.000), and clinical nonmajor bleeding (1 (2.3%; 95% CI, 0.0-6.9) vs 1 (2.2%; 95% CI, 0.0-6.7)) but demonstrated a lower risk of any bleeding (1 (2.3%; 95% CI, 0.0-6.9) vs 9 (20.0%; 95% CI, 7.8-32.2)) compared with the warfarin group. Most patients in both groups achieved venous recanalization according to the Modified Qureshi scale (27 (75%; 95% CI, 60.1-89.9) in the dabigatran etexilate group vs 34 (82.9%; 95% CI, 70.9-95.0) in the warfarin group) and exhibited improvement in papilledema as per the Frisén classification (35 (97.2%; 95% CI, 91.6-100.0) in the dabigatran etexilate group vs 37 (88.1%, 95% CI, 77.9-98.3) in the warfarin group). CONCLUSIONS: These findings regarding efficacy and safety support the consideration of dabigatran etexilate therapy as a viable treatment option for Chinese patients with CVT.
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Anticoagulantes , Dabigatrán , Trombosis Intracraneal , Trombosis de la Vena , Warfarina , Humanos , Dabigatrán/uso terapéutico , Dabigatrán/efectos adversos , Masculino , Femenino , Warfarina/uso terapéutico , Warfarina/efectos adversos , Persona de Mediana Edad , Trombosis de la Vena/tratamiento farmacológico , Adulto , Anticoagulantes/uso terapéutico , Anticoagulantes/efectos adversos , Trombosis Intracraneal/tratamiento farmacológico , Anciano , China/epidemiología , Hemorragia/inducido químicamente , Antitrombinas/uso terapéutico , Antitrombinas/efectos adversos , Adulto Joven , Adolescente , Resultado del Tratamiento , Anciano de 80 o más Años , Pueblos del Este de AsiaRESUMEN
Heavy metals (HMs) present in the natural aquatic environment can form a ternary aggregate of "EPS-DOM-HMs" with the prevalent microalgae extracellular polymers substances (EPS) and macromolecular dissolved organic matters (DOMs), which show special molecular structure and biological interaction. This study reveals the formation of "EPS-TA-HMs" and the mechanism of their physiological and metabolic effects on Raphidocelis subcapitata. Results indicate that TA-Cr(III) can bind to EPS to form ternary aggregates with substances coexisting large and small hydrodynamic diameters and that the interactions are dominated by hydrophobic interactions of the protein binding to the pyrrole ring of the polyphenol and hydrogen bonding interactions formed by OC-(N R O). The protein structure of EPS has the largest proportion of proline, glycine, aspartic acid, and tryptophan. These interactions promoted the secretion of EPS components and reduced the growth inhibition of Raphidocelis subcapitata by 45.9 % compared with Cr(III) exposure. TEM analysis combined with EDS analysis indicated that Cr(III) was taken intracellularly and TA-Cr(III) was not. In addition, metabolomics analyses revealed that microalgae initiate adaptive mechanisms via the activation of a two-component system (i.e., maintenance of high metabolic activity). This study underscored the morphology of HMs in real aquatic environments and the mechanisms of metabolic effects on aquatic organisms.
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Polychlorinated Biphenyls (PCBs) and Organochlorinated Pesticides (OCPs) are 'trapped' in a variety of environmental media and can therefore undergo further processing by geochemical cycles. By reviewing a wide range of research studies, we present and discuss the main progresses that affect legacy contaminants, such as migration and transformation processes, biological effects assessment across all Arctic media. PCBs and OCPs demonstrated an overall decreasing concentration trend over time in the Arctic. Ecological risk assessment was undertaken by comparison with two standards, suggesting that there was no ecological risk in either soil or sediment. The concentrations of HCB, ΣHCHs, ΣDDTs, chlordane, mirex, and ΣPCBs increased with trophic levels (TLs), showing a significant linear correlation (P < 0.001). The calculated trophic magnification factors (TMFs) values ranged from 0.0004 to 26.63, among which DDTs had the highest value. Future research need to focus on the long-term fate of PCBs and OCPs.
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Objectives: Anticoagulation therapy for cerebral venous sinus thrombosis (CVST) with antithrombin (AT) deficiency due to SERPINC1 mutation does not often yield the expected outcomes. Argatroban may be effective for thrombophilia caused by SERPINC1 mutation. However, argatroban resistance deserves attention. Methods: We report a case of a 19-year-old man who was admitted to the hospital with sudden headache, nausea, vomiting, and eye swelling for 3 days. Brain MRI on admission showed multifocal CVST. Results: SERPINC1 mutation (exon1, c.40delA: [p.R14Gfs*17]) combined with hereditary AT deficiency (AT activity was 50% [reference range: 80%-120%]) was detected in this patient. A high dose of anticoagulation treatment with argatroban did not improve the activated partial thromboplastin time (APTT) level to the target range (1.5-3 times over the initial baseline level) for this case. We chose adjunctive anticoagulation (argatroban-combined low-molecular-weight heparin), and the APTT gradually reached the target level. At 3-month follow-up, no recurrence of headache or any systemic hemorrhage was found and the ultrasonography of the optic nerve sheath showed normal. Magnetic resonance black blood thrombosis imaging suggested thrombus absorption. Discussion: Argatroban resistance may be associated with thrombin receptor saturation and deserves attention. The use of adjunctive anticoagulants may be the optimum strategy during acute and subacute phases of CVST with AT deficiency due to SERPINC1 mutation.
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The electrochemical nitrate reduction reaction (NitRR) affords a sustainable way for nitrate mitigation and ammonia synthesis, but there are still some problems such as poor nitrate conversion, low ammonia selectivity, and slow reaction kinetics. A clear structure-performance relationship is essential for designing efficient catalysts and understanding the reaction mechanisms. Herein, ultrathin nickel metal-organic framework (Ni-MOF) nanosheets supported on Ni foam featuring a well-defined stable structure, large electrochemically active surface area, and low electron transport resistance were prepared by a one-step solvothermal process. At -1.4 V, the nitrate reduction, rate constant, ammonia selectivity, and yield reached 96.4%, 0.448 h-1, 80%, and 110.13 ug·h-1·cm-2, respectively. Experimental and theoretical studies demonstrated that the hydroxyl-ligated Ni atoms exhibited higher nitrate adsorption properties and lower activation energy towards NitRR compared to carboxylic acid-ligated Ni atoms. Mechanism investigations revealed a nitrate-to-ammonia reaction pathway involving multiple intermediate species on Ni-MOF nanosheet catalysts. This work offers a new avenue to construct highly efficient electrocatalysts for the selective transformation of nitrate to valuable ammonia.
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Estructuras Metalorgánicas , Nitratos , Amoníaco , Níquel , Teoría Funcional de la DensidadRESUMEN
AIMS: To investigate the predicted factors influencing the outcomes in acute ischemic stroke (AIS) patients who received tirofiban after endovascular treatment (EVT) and the optimal administration of tirofiban. METHODS: In this retrospective study, AIS patients who received EVT followed by tirofiban between January 2017 and October 2021 were enrolled. The dose and duration of tirofiban were adjusted by trained clinicians according to the patient's clinical status. A reduction of at least four points on the National Institutes of Health Stroke Scale (NIHSS) after tirofiban compared with that before tirofiban was defined as an effective response. A modified ranking scale (mRS) of 0-2 was defined as a favorable outcome at a 90-day follow-up. RESULTS: A total of 260 consecutive patients were enrolled, and 36.5% of patients achieved a favorable outcome. The modified thrombolysis in cerebral infarction (mTICI) 2b-3 occurred in 93.5% of patients. Symptomatic intracerebral hemorrhage (sICH) occurred in 6.2% of patients, and the mortality at 90-day follow-up was 16.9%. Duration of tirofiban >24 h (adjusted OR: 2.545; 95% CI: 1.008-6.423; p = 0.048) and effective response to tirofiban (adjusted OR: 25.562; 95% CI: 9.794-66.715; p < 0.001) were related to the favorable outcome (mRS 0-2). Higher NIHSS (adjusted OR: 0.855; 95% CI: 0.809-0.904; p < 0.001) and glucose level on admission (adjusted OR: 0.843; 95% CI: 0.731-0.971; p = 0.018) were predictive for the unfavorable outcome (mRS 3-6). CONCLUSIONS: An effective response to tirofiban is an independent factor in predicting the long-term efficacy outcome, and extending the duration of tirofiban is beneficial for neurological improvement.
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Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Tirofibán/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/cirugía , Estudios Retrospectivos , Isquemia Encefálica/tratamiento farmacológico , Resultado del TratamientoRESUMEN
Organophosphate esters (OPEs) are widely distributed in surface water systems, but limited information was available on the spatial occurrence and ecological risks of OPEs in the Bohai Sea. In this study, 89 water samples in the Bohai Sea and the five surrounding rivers were investigated for the determination of 15 OPEs. The concentration of ∑15OPEs ranged from 373.20 to 2931.27 ng·L-1 in the river water and 137.81 to 2641.30 ng·L-1 in the seawater, with high levels of OPEs in Liaodong Bay. Tris(2-chloroethyl) phosphate (TCEP, 10- 92 %) and triethyl phosphate (TEP, 5- 64 %) were dominant for OPEs. The correlation analysis, principal component analysis and hierarchical cluster analysis suggested the conjunction of municipal wastewater via river input and maritime shipping was the main source of OPEs in the Bohai Sea. The ecological risk assessment indicated that the individual OPEs arise low ecological risks in the Bohai Sea, while medium ecological risks of ∑15OPEs are in minority river samples.
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Retardadores de Llama , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Retardadores de Llama/análisis , Contaminantes Químicos del Agua/análisis , Ésteres/análisis , Organofosfatos/análisis , Agua de Mar , Agua/análisis , ChinaRESUMEN
Substituted polycyclic aromatic hydrocarbons (SPAHs) are a type of emerging pollutant that widely exist in the environment, which also exhibit carcinogenicity, mutagenicity, and teratogenicity. These pollutants belong to toxic pollutants because of their similar structures to polycyclic aromatic hydrocarbons (PAHs). Their environmental behavior and ecological risk have attracted increasing attention. Based on a literature review, we found a new breakthrough in the source, distribution, behavior, and risk of SPAHs with comparison to traditional pollutants PAHs. This paper reviewed the current research progress on the environmental occurrence and photochemical behavior of SPAHs. Their sources, formation mechanisms, and distribution characteristics in the multimedia environment were highlighted, and the photochemical transformation kinetics, pathways, and affecting factors of SPAHs in water, ice, and other media were discussed. Furthermore, the research prospects about the environmental behavior and risk of SPAHs were proposed.