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Rare-earth (RE)-based frustrated magnets are fertile playgrounds for discovering exotic quantum phenomena and exploring adiabatic demagnetization refrigeration applications. Here, we report the synthesis, structure, and magnetic properties of a family of rare-earth cyanurates RE5(C3N3O3)(OH)12 (RE = Gd-Lu) with an acentric space group P6Ì 2m. Magnetic susceptibility χ(T) and isothermal magnetization M(H) measurements manifest that RE5(C3N3O3)(OH)12 (RE = Gd, Dy-Yb) compounds exhibit no magnetic ordering down to 2 K, while Tb5(C3N3O3)(OH)12 shows long-range magnetic ordering around 3.6 K. Among them, magnetically frustrated spin-7/2 Gd5(C3N3O3)(OH)12 shows long-range magnetic ordering around 1.25 K and a large magnetocaloric effect with a maximum magnetic entropy change ΔSm of up to 58.1 J kg-1 K-1 at ΔH = 7 T at liquid-helium temperature regimes.
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Triangular lattice (TL) materials are a rich playground for investigating exotic quantum spin states and related applications in quantum computing and quantum information. Millimeter-level single crystals of REBO3 (RE = Tb-Yb) with a nearly perfect RE-based TL have been successfully grown via a high-temperature flux method and structurally characterized via single-crystal X-ray diffraction. These 113-type materials crystallize in a monoclinic crystal system with a C2/c space group. Anisotropic magnetism and dominant antiferromagnetic interactions are found for the above materials based on DC magnetic susceptibility measurements. The comprehensive low-temperature specific heat data of REBO3 (RE = Tb-Tm) are characterized on single crystals for the first time, which exhibit diverse magnetic behaviors. Specifically, two weak-field-induced transitions could be found in the case of DyBO3 based on the specific heat measurements. Our results suggest that REBO3 (RE = Tb-Yb) is a TL magnetic system for investigating potential quantum magnetism.
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OBJECTIVES: To assess and compare the effectiveness of various treatment approaches for laryngeal contact granulomas (LCG). METHODS: A retrospective analysis was conducted on a cohort of 45 patients diagnosed with LCG at the Second Affiliated Hospital of Xi'an Jiaotong University from October 2017 to May 2023. Based on the treatment modalities administered, patients were categorized into three groups: acid suppression alone, hormone injection combined with acid suppression, and surgery combined with acid suppression. Subsequently, the study compared differences in treatment efficacy and average healing time among these three groups, using various indicators. RESULTS: The findings indicate that the granuloma size in LCG patients with hoarseness (0.126, 95% CI 0.087-0.288) was significantly greater compared to LCG patients without hoarseness (0.047, 95% CI 0.014-0.083) (P = 0.001). However, there were no significant variations in age, morphology (unlobulated/lobulated), laterality ratio (left/right), sex ratio (male/female), history of tracheal intubation (non-intubation/intubation), and RFS score (RFS > 7/RFS ≤ 7) (P > 0.05), regardless of the presence of hoarseness symptoms. At the treatment observation endpoint of 3 months, the curative ratio in the group receiving hormone injection combined with acid suppression was found to be significantly higher compared to the group receiving acid suppression alone (P = 0.018). In addition, the average healing time of patients in the hormone injection combined with acid suppression group was notably shorter than that of the acid suppression alone group (P = 0.007). CONCLUSIONS: The combination of hormonal injections and acid suppression may enhance the curative ratio and expedite the healing time of LCG.
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Granuloma Laríngeo , Ronquera , Humanos , Masculino , Femenino , Estudios Retrospectivos , Ronquera/etiología , Ronquera/terapia , Granuloma Laríngeo/cirugía , Granuloma , HormonasRESUMEN
Quasi-1D chain antiferromagnets with reduced structural dimensionality are a rich playground for investigating novel quantum phenomena. We report the synthesis, crystal structure, and magnetism of two novel quasi-1D antiferromagnets, ß-PbCu2(TeO3)2Cl2 (I) and PbCu2(TeO3)2Br2 (II). Their magnetic frameworks are constructed via Cu-based quasi-1D [Cu(2)O4] zigzag chains with square-planar [Cu(1)O2X2] (X = Cl or Br) separated among 1D chains. Specific heat measurements show l peaks at ~9 K and ~19 K for I and II, respectively. Moreover, both broad maximums (χmax = 90 K for I and 80 K for II) and small kinks (TN ≈ 9 K for I and 19 K for II) have been observed in magnetic susceptibility measurements of I and II. Bonner-Fisher model fitting, and theoretical analyses were performed to evaluate the magnetic exchange interactions. Our experimental and theoretical results and structure-properties relationship analysis reveal the coexistence of short- and long-range magnetic ordering from the cooperative effect of 1D [CuO4] chains and [CuO2X2] quadrilateral.
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Nonlinear optical (NLO) crystals, being the primary medium for laser wavelength conversion, are crucial in all-solid-state lasers. Borophosphates offer more structural varieties than pure borates and phosphates, and they have become popular as NLO crystal candidates. Through spontaneous crystallization, we acquired a noncentrosymmetric alkali metal borophosphate crystal material, K2Na3B2P3O13 (KNBPO). KNBPO crystallizes in the orthorhombic Cmc21 space group with the following unit cell parameters: a = 13.9238(18) Å, b = 6.7673(8) Å, c = 12.1298(15) Å, and Z = 4, and its structure is characterized by a fundamental building unit 1∞ [B2P3O13] chain structure made up of bridging oxygen linkages between BO4 and PO4 tetrahedra. KNBPO has a short ultraviolet (UV) cut-off edge (<186 nm), a congruent melting characteristic, good thermal stability, and a moderate second harmonic generation response roughly 0.42 times that of KH2PO4. Theoretical calculations reveal that the optical properties of the compound mainly originate from BO4 and PO4 units. Due to the short UV cut-off edge, KNBPO can be used as a potential NLO material in the UV and even deep UV regions, and it enhances the structural variety of borophosphates, which has a reference value for scholars investigating similar materials.
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Ba1.09Pb0.91Be2(BO3)2F2 (BPBBF), a previously unreported lead-containing beryllium borate fluoride, has been successfully grown through a high-temperature flux method. Its structure is solved by single-crystal X-ray diffraction (SC-XRD), and it is optically characterized via infrared, Raman, UV-vis-IR transmission, and polarizing spectra as well. SC-XRD data suggests that it can be indexed by a trigonal unit cell (space group P3m1) with lattice parameters a = 4.7478(6) Å, c = 8.3856(12) Å, Z = 1, and V = 163.70(5) Å. This material could be considered as a derivative of the Sr2Be2B2O7 (SBBO) structural motif. It consists of 2D [Be3B3O6F3]∞ layers in the crystallographic ab plane, with divalent Ba2+ or Pb2+ cations serving as spacers among the adjacent layers. Ba and Pb were found to adopt a disordered arrangement in the trigonal prismatic coordination within the BPBBF structural lattice, which is evidenced by both structural refinements against SC-XRD data and energy dispersive spectroscopy. The UV absorption edge (279.1 nm) and birefringence (Δn = 0.054@ 546.1 nm) of BPBBF are confirmed by UV-vis-IR transmission and polarizing spectra, respectively. The discovery of this previous unreported SBBO-type material, BPBBF, along with other reported analogues such as BaMBe2(BO3)2F2 (M = Ca, Mg, and Cd), provide a prodigious example for tuning the bandgap, birefringence, and short UV absorption edge via simple chemical substitution.
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A new Gd3+-containing borate Ba2Gd(BO3)2F has been successfully grown via the high-temperature solution method using BaF2-NaF-B2O3 flux. Ba2Gd(BO3)2F crystallizing in the orthorhombic space group Pnma is with lattice parameters a = 7.571(4) Å, b = 10.424(5) Å, c = 8.581(4) Å, α = ß = γ = 90°, and Z = 2. Its three-dimensional framework was constructed from interesting pinwheel-like [Gd(BO3)F]∞ layers bridged by sharing [BO3]3-, which is different from the [Gd(BO3)]∞ layer in the model structure Ba2Gd(BO3)2Cl. The magnetic measurements indicated that Ba2Gd(BO3)2F has a larger magnetocaloric effect with -ΔSm,max = 27.82 J·kg-1·K-1at 2 K and 9 T than that of Ba2Gd(BO3)2Cl under the same conditions. Moreover, thermal stability, infrared spectrum (IR), and ultraviolet-visible-near-infrared diffuse reflectance spectrum were carried out to characterize the title compounds. The first-principles computations also looked into the electronic band structures, densities of states, and refractive indices.
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OBJECTIVE: To analyze the risk factors for recurrence of laryngeal amyloidosis (LA). METHODS: The clinical data of patients with LA admitted in the Otolaryngology Head and Neck Surgery Department of the Second Affiliated Hospital of Xi'an Jiaotong University from August 2009 to June 2022 were analyzed retrospectively; then, the risk factors for recurrence and their impacts on the recurrence time were also analyzed. RESULTS: Of the 44 patients with LA, the majority (38 cases, 86.4%) only involved one anatomical region and the others (6 cases, 13.6%) involved two laryngeal regions concurrently. Overall, the glottic region was the most commonly affected area (28 cases, 63.6%), followed by the supraglottic region (16 cases, 36.4%) and subglottic region (6 cases, 13.6%). In addition, all the lesions were categorized as isolated nodule (31.8%), submucosal localized deposition (52.3%), and submucosal diffuse deposition (15.9%) according to their morphologies under electronic laryngoscope. Finally, six patients (13.6%) had recurrence after operation with a median recurrence time of 24.5 months, and subglottic involvement was confirmed to be an independent risk factor for recurrence of LA by univariate and multivariate logistic regression analyses (P < 0.05). Meanwhile, the patients with subglottic involvement presented as submucosal diffuse deposition had a considerable shorter recurrence time (t = 5.759, P = 0.005). CONCLUSION: The subglottic involvement is an independent risk factor for recurrence of LA.
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Amiloidosis , Neoplasias Laríngeas , Laringe , Humanos , Neoplasias Laríngeas/cirugía , Estudios Retrospectivos , Laringe/patología , Factores de RiesgoRESUMEN
Birefringence, as one of the most important factors for birefringent materials, governs their performances in applications. In this study, two previously unreported beryllium borates, BaCdBe2(BO3)2F2 (BDBBF) and NaMgBe2(BO3)2F (NMBBF), have been rationally designed by modulating interstitial cations. When smaller sizes of the cations are used, the crystal structure of NMBBF exhibits closer-packed 2D [Be6B6O12F3]∞ double layers rather than the 2D [Be3B3O6F3]∞ single layers in the crystal structure of BDBBF. The ultraviolet (UV) transmittance spectrum indicates that the short UV absorption edges of BDBBF and NMBBF are below 200 nm. The results from both theoretical calculations (theo.) and experimental characterizations (exp.) reveal enlarged birefringence from BDBBF (0.067 at 589 nm from theo. and 0.059 at 546.1 nm from exp.) to NMBBF (0.078 at 589 nm from theo. and 0.081 at 546.1 nm from exp.). Because of its excellent structure-based optical properties, NMBBF has the potential to be a deep-UV birefringent material. Our structural comparison and discussion provide a scope to aid in the design of potential deep-UV birefringent materials with large birefringence.
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As the emerging contaminants, the environmental risks of drug-derived pollutants have attracted extensive attention. Citalopram (CTP) and mirtazapine (MTP) are commonly used as modern antidepressant drugs. Previous studies had proved that CTP and MTP entered the aquatic environment, but less reported the negative effects of the drugs on aquatic organisms. Herein, the effects on the feeding rate of Daphnia magna (D. magna) induced by psychotropic drugs CTP and MTP were investigated, which the possible mechanisms were analyzed with the oxidative stress and damage. Generally, the feeding rates of exposed D. magna under all concentrations of CTP and 1.03 mg/L of MTP were significantly decreased after exposure (p < 0.05 or p < 0.01). The inhibitory effect of CTP on the feeding rate of D. magna was time- and dose-dependent. The levels of reactive oxygen species (ROS) were particularly increased in D. magna after CTP and MTP exposure (p < 0.05 or p < 0.01). The level of antioxidant molecules glutathione S-transferase (GST) and the activity of scavenging enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) of D. magna were increased (p < 0.05 or p < 0.01). In consequence, the levels of malondialdehyde (MDA), protein carbonyl, and 8-hydroxydeoxyguanosine (8-OHdG) were increased (p < 0.05 or p < 0.01), which indicated oxidative damage caused by MTP and CTP, due to the imbalance of antioxidative stress system. These findings indicated that psychoactive drugs posed a high toxic threat to the aquatic organisms, and the aquatic environmental risks caused by using psychoactive drugs deserve more attention.
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OBJECTIVE: To investigate the effect of Helicobacter pylori (HP) eradication therapy on salivary pepsin concentration in laryngopharyngeal reflux (LPR) patients with HP infection. MATERIALS AND METHODS: A total of 477 patients with suspected LPR were enrolled from June 2020 to September 2021. Reflux symptom index, reflux finding score, the positive rates and disintegrations per minute values of HP infection detected by 14C urea breath test and salivary pepsin concentrations analyzed using enzyme-linked immunosorbent assay were compared in LPR patients and non-LPR patients with or without HP infection. HP-positive patients were treated with HP eradication therapy while HP-negative patients with PPI therapy. RESULTS: The scores of nagging cough (0.88 vs. 0.50, P = 0.035), erythema or hyperemia (1.93 vs. 1.78, P = 0.035) and vocal fold edema (1.04 vs. 0.85, P = 0.025) were higher in the LPR (+) Hp (+) subgroup than in LPR (+) Hp (-) subgroup. The concentrations of salivary pepsin in the Hp (+) subgroup were higher than in the Hp (-) subgroup either in LPR patients (75.24 ng/ml vs. 61.39 ng/ml, P = 0.005) or the non-LPR patients (78.42 ng/ml vs. 48.96 ng/ml, P = 0.024). Compared to baseline (before treatment), scores of nagging cough (0.35 vs. 0.84, P = 0.019) and erythema or hyperemia (1.50 vs. 1.83, P = 0.039) and the concentrations of salivary pepsin (44.35 ng/ml vs. 74.15 ng/ml, P = 0.017) in LPR patients with HP infection decreased after HP treatment; yet, this was not observed for the LPR patients without HP infection treated with PPI only (P > 0.05). CONCLUSION: HP infection may aggravate the symptoms and signs of LPR patients, partly by increasing their salivary pepsin concentration.
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Helicobacter pylori , Hiperemia , Reflujo Laringofaríngeo , Tos , Humanos , Reflujo Laringofaríngeo/complicaciones , Reflujo Laringofaríngeo/diagnóstico , Reflujo Laringofaríngeo/tratamiento farmacológico , Pepsina A , Saliva , UreaRESUMEN
An alkali-metal bismuth iodate, Na3Bi(IO3)6, was successfully obtained by the hydrothermal method for the first time and contains intriguing one-dimensional [BiI6O18] chains. High-pressure Raman spectra were carried out to investigate the structural transition of Na3Bi(IO3)6. Electronic states and anisotropic optical responses were also investigated by theoretical calculations.
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Birefringent crystals with optical anisotropy, which are employed to modulate the polarization of light, play a vital role in many fields of the optical industry. In this Communication, two mixed alkali metal hydroisocyanurates, RbLi(H2C3N3O3)2·2H2O (I) and CsLi(H2C3N3O3)2·2H2O (II), were synthesized by a simple aqueous solution method, and they feature layered structures composed of ∞2[H2C3N3O3]- ribbons through hydrogen bonds with the separation of water molecules and alkali cations. They exhibit a simultaneously short ultraviolet cutoff and giant birefringence, resulting from the perfect parallel alignment of π-conjugated (H2C3N3O3)- anions. Interestingly, the first-principles calculations elucidated that the electronic states and optical properties are slightly different owing to the distinct p-π interaction between alkaline metals and the (H2C3N3O3)- group despite the isostructural crystallographic lattice.
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Due to the extensive use in consumer products, the bisphenols (BPs) pollution in the environments has aggravated and people are frequently exposed to BPs. In this research, four BPs, i.e., bisphenol A (BPA), bisphenol F (BPF), bisphenol S (BPS) and bisphenol AF (BPAF), were determined in urine samples collected from Gaochun District preschool-age children and the concentrations, distribution profiles, potential sources and cumulative risk assessment of the target compounds were studied. Total concentrations of 4 BPs ranged from 2 to 3113.1â¯ng/L, with the average concentration of 648.6â¯ng/L. BPA was the predominant congener (accounting for 94%), followed by BPS. Correlation analysis indicated a negative relationship between BPA and BPAF (R = -0.273, pâ¯<â¯0.05). The estimated daily intakes suggested that young females were more sensitive to BPs. Moreover, the cumulative risk for hazard quotient (HQ) of BPA has been evaluated and the results showed that no high risk had occurred. It provided basic information on the occurrence and human exposure to urinary BPs of preschool aged children from Gaochun District.
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Compuestos de Bencidrilo/orina , Fenoles/orina , Sulfonas/orina , Niño , Preescolar , China , Exposición a Riesgos Ambientales , Femenino , Humanos , Masculino , Medición de Riesgo , Tamaño de la MuestraRESUMEN
Because the application of Bisphenol A (BPA) was restricted, many substitutes, such as Bisphenol F (BPF) and Bisphenol S (BPS), were developed as BPA substitutes. Therefore, environmental impacts of BPA and its substitutes on aquatic organisms should be concerned, especially their combined toxicity. In this study, the impacts of BPA, BPF, BPS and their mixture on the feeding behavior, reproduction and physiological function of daphnids were synthetically evaluated, involving the duration and mode of exposure. In short-term exposure tests, feeding rates of D. magna decreased after exposure to BPA, BPF, BPS and their mixture, while the inhibition reversed into stimulation in the recovery period. It may benefit from overcompensation of D. magna. In long-term exposure tests, the inhibition effect on the reproduction and growth of the exposed D. magna was difficult to recover, and only some experimental groups have a certain recovery. In conclusion, environmental risk of BPA, BPF, BPS and their mixture on the behavior of D. magna increased with prolonged exposure time. Moreover, relative activities of trypsin, amylase (AMS), acetylcholinesterase (AChE), carbonic anhydrase (CA), glutathione peroxidase (GPx) and super oxidase dimutase (SOD) of the exposed daphnids decreased in most treatment groups, indicating the disorder of digestive, nervous and antioxidative system of D. magna. Interestingly, inhibition of enzymes activities decreased with the increase of the exposure time, which implied the tolerance may be occurred.
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Compuestos de Bencidrilo/toxicidad , Daphnia/efectos de los fármacos , Fenoles/toxicidad , Reproducción/efectos de los fármacos , Acetilcolinesterasa/metabolismo , Animales , Anhidrasas Carbónicas/metabolismo , Daphnia/metabolismo , Glutatión Peroxidasa/metabolismo , Sulfonas/toxicidad , Superóxido Dismutasa/metabolismo , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad CrónicaRESUMEN
Quantum dots (QDs), as a kind of novel nanomaterial, have the extensive applications in various fields, inevitably leading to increasing risks for the ecological environment. The mobilization of cadmium including metal smelting and subsequent machining for multifarious applications has caused the release of cadmium element into the environment. In this study, we evaluated the potential toxicity of a novel nanoparticle material CdSe QDs, using two green algae Chlorella pyrenoidosa and Scenedesmus obliquus. The impact of CdSe QDs and cadmium ions on algae and the sensitivity of the two algae on target compounds were also considered and compared. Our results showed the algal growth rates and chlorophyll content decreased with increasing exposure concentrations and durations. Moreover, the glutathione levels were decreased while the activities of superoxide dismutase increased, exhibiting their pivotal functions in defeating toxic stress. The increment of malondialdehyde levels revealed that the stresses of CdSe QDs and cadmium ions were contributed to the occurrence of oxidative damage. Our study also indicated that the impact of CdSe QDs was stronger than that of cadmium nitrate and the algal response was also species-specific. In addition, the TEM photographs of the algal ultrastructure showed the presence of surface attachment and uptake of QDs.
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Compuestos de Cadmio/toxicidad , Chlorella/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Puntos Cuánticos/toxicidad , Scenedesmus/efectos de los fármacos , Compuestos de Selenio/toxicidad , Chlorella/crecimiento & desarrollo , Chlorella/metabolismo , Clorofila/metabolismo , Relación Dosis-Respuesta a Droga , Malondialdehído/metabolismo , Metalurgia , Scenedesmus/crecimiento & desarrollo , Scenedesmus/metabolismo , Superóxido Dismutasa/metabolismoRESUMEN
The widespread use of bisphenol S (BPS) as a bisphenol A substitute increases its potential of release into the aquatic environments. However, the degradation of BPS in aquatic systems is largely unknown, which will dictate its fate and toxicity. In this study, a bacterial consortium was enriched from river sediments and the dynamic changes of community structure during bacterial acclimation were studied. BPS degrading bacterial strains isolated from the consortium were identified by 16S rRNA analysis. The efficiency of the consortium and strains for BPS degradation were further evaluated. After 28 days of acclimation, the microbial diversity decreased significantly and four bacterial genera Hyphomicrobium, Pandoraea, Rhodococcus, and Cupriavidus with relative abundances of 5.1%-52.8% became dominant in the consortium. Total of two pure strains including Terrimonas pekingensis and Pseudomonas sp. were isolated from the consortium, using BPS as the sole carbon source. The consortium was highly efficient to degrade BPS, and 99% of BPS with an initial concentration of 50 mg/L was removed within 10 days at pH 7 and 30°C. In comparison with the consortium, a single strain cultures had lower BPS degradation efficiency. These findings indicate that BPS will degrade rapidly under aerobic conditions in river sediments and have implication for BPS-contaminated site remediation using the enriched consortium.
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Biodegradación Ambiental , Sedimentos Geológicos/microbiología , Fenoles/metabolismo , Sulfonas/metabolismo , Bacterias/metabolismo , Compuestos de Bencidrilo , Sedimentos Geológicos/química , Consorcios Microbianos , Pseudomonas/genética , ARN Ribosómico 16S/genética , Rhodococcus , RíosRESUMEN
This innovative study provided a comprehensive evaluation of the effects of three typical antibiotics exposures (cefradine, norfloxacin and amoxicillin) on Microcystis aeruginosa in two periods (exposure and post-exposure) at a new perspective. The results indicated that the irreversible growth inhibition of M. aeruginosa attributed to the norfloxacin in the exposure and the re-exposure stages. In contrast, although the algal cell size recovered to the control level after the exposure of 20â¯mg/L of cefradine, the significant stimulation on glutathione (GSH) still persisted even if the contaminants were removed. On the other hand, amoxicillin inhibited the activities of superoxide dismutase (SOD), GSH contents and the algal cell size in the exposure period while malonaldehyde (MDA) contents increased significantly in two periods.
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Antibacterianos/toxicidad , Microcystis/efectos de los fármacos , Amoxicilina/toxicidad , Cefradina/toxicidad , Glutatión/metabolismo , Malondialdehído/metabolismo , Microcystis/crecimiento & desarrollo , Norfloxacino/toxicidad , Superóxido Dismutasa/metabolismoRESUMEN
Compared to traditional toxicological studies, which depict the dose-effect of contaminants themselves on organisms at the given time, the exposure and post-exposure impacts of antibiotic ceftazidime and its photoproducts are carried out to systematically evaluate the environmental risk fate of ceftazidime in aquatic environments. For the exposure process, the promotion effect of ceftazidime on the feeding behavior of the rotifers decreased when the target compound was irradiated by sunlight, and the promotion effect was converted into inhibition effect, which indicated that the highest toxicity of ceftazidime on the feeding behavior of the rotifers was found after UV-B irradiation. The overcompensation occurred in the post-exposure, indicating a short - term effect of the corresponding photoproducts on the rotifer. In order to better understand the mechanism of this change, the photodegradation pathways of the target compound was analyzed and compared. The degradation degree under the UV-B irradiation had intensified greatly than that under the nature light irradiation. The reactive oxygen species (ROS) of the rotifer in exposure and post-exposure was also detected. Ceftazidime and photoproducts induced generation of ROS, indicating that oxidative damage occurred, and the decreasing of ROS levels could be viewed as the recovery of the rotifers in the post-exposure.
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Ceftazidima/toxicidad , Monitoreo del Ambiente/métodos , Conducta Alimentaria/efectos de los fármacos , Luz , Rotíferos/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Ceftazidima/efectos de la radiación , China , Fotólisis , Especies Reactivas de Oxígeno/metabolismo , Luz Solar , Rayos Ultravioleta , Contaminantes Químicos del Agua/efectos de la radiaciónRESUMEN
The occurrence and distribution of eight selected endocrine-disrupting chemicals were investigated in samples of surface water and suspended particulate matter (SPM) in Nanjing section of Yangtze River over a year (the flow period, the wet period and the dry period). All target compounds were detected at least once in surface water with 4-tert-butylphenol (4-TBP), nonyphenol (NP) and bisphenol A (BPA) as the dominant compounds, with concentrations in the range of 225-1121ng/L, 1.4-858ng/L and 1.7-563ng/L, respectively. Except for December, all selected compounds for the other sampling times were not found in all sampling points. NP (mean concentration 69.8µg/g) and BPA (mean concentration 51.8µg/g) were also the dominant estrogens in SPM. In addition, the highest total compounds concentrations were found in December in both phases, which could be due to the low flow conditions and temperature during this season. Meanwhile, a significant positive correlation was found between the total compounds concentrations in the water phase and those in SPM phase. Risk assessment based on the calculated risk quotients (RQ) showed that low and moderate risk for the aquatic environment from presence of the target compounds at all sampling points with exception of 4-TBP and NP which might pose a high risk to aquatic organisms.