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1.
Sci Total Environ ; 926: 171993, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38547967

RESUMO

Calcium nitrate addition is economically viable and highly efficient for the in-situ treatment of contaminated sediment and enhancement of surface water quality, particularly in rural areas. However, conventional nitrate addition technologies have disadvantages such as excessive nitrate release, sharp ammonium increase, and weakened sulfide oxidation efficiency owing to rapid nitrate injection into the sediment. To resolve these defects, we propose a piped-slow-release (PSR) calcium nitrate dosing method and investigate its treatment efficiency and underlying mechanisms. The results illustrated that PSR dosing had a longer half-life (t1/2 = 5.08 days) and a lower maximum apparent nitrate escape rate of 1.28 % than conventional nitrate injection and other dosing methods. In addition, the PSR managed the inorganic nitrogen release into the overlying water, and after the treatment, the nitrate, ammonium, and nitrite concentrations of 0 mg/L, 8.60 mg/L, and 0 mg/L on day 28 were close to those of the control group (0 mg/L, 8.76 mg/L, and 0 mg/L, respectively). Moreover, the PSR method maintained a moderate nitrate concentration of approximately 3000 mg/L in sediment interstitial water by its controlled-release design, thus greatly enhancing the sulfide oxidation efficiency by relieving the inhibitory effects of high nitrate concentrations, with 83.0 % sulfide being eradicated within 5 days. Sulfide-ferrous nitrate reduction (denitrification and dissimilatory nitrate reduction to ammonium) genera (e.g., Sulfurimonas, Thiobacillus, and Thioalkalispira) were successively enhanced and dominated the microbial community, and the related functional genes displayed high relative abundances. These results imply that the PSR dosing method for calcium nitrate, characterized by flexible operation, high efficiency, low cost, and controllable processes, is appropriate for remediating black-odorous sediment in rural areas.


Assuntos
Compostos de Amônio , Compostos de Cálcio , Nitratos , Odorantes , Sulfetos , Nitrogênio , Oxirredução , Desnitrificação
2.
Environ Res ; 248: 118137, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38295972

RESUMO

Since nitrate nitrogen (NO3--N) input has proved an effective approach for the treatment of black and odorous river waterbody, it was controversial whether the total nitrogen concentration standard should be raised when the effluent from the sewage treatment plant is discharged into the polluted river. To reveal the effect of exogenous nitrate (NO3--N) on black odorous waterbody, sediments with different features from contaminated rivers were collected, and the changes of physical and chemical characteristics and microbial community structure in sediments before and after the addition of exogenous NO3--N were investigated. The results showed that after the input of NO3--N, reducing substances such as acid volatile sulfide (AVS) in the sediment decreased by 80 % on average, ferrous (Fe2+) decreased by 50 %, yet the changing trend of ammonia nitrogen (NH4+-N) in some sediment samples increased while others decreased. High-throughput sequencing results showed that the abundance of Thiobacillus at most sites increased significantly, becoming the dominant genus in the sediment, and the abundance of functional genes in the metabolome increased, such as soxA, soxX, soxY, soxZ. Network analysis showed that sediment microorganisms evolved from a single sulfur oxidation ecological function to diverse ecological functions, such as nitrogen cycle nirB, nirD, nirK, nosZ, and aerobic decomposition. In summary, inputting an appropriate amount of exogenous NO3--N is beneficial for restoring and maintaining the oxidation states of river sediment ecosystems.


Assuntos
Microbiota , Nitratos , Nitrogênio/análise
3.
Sci Total Environ ; 915: 170116, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38232831

RESUMO

Pyrolysis is an effective method for treating of livestock and poultry manure developed in recent years. It can completely decompose pathogens and antibiotics, stabilize heavy metals, and enrich phosphorus (P) in biochar. To elucidate the P migration mechanism under different pig manure pyrolysis temperatures, sequential fractionation, solution 31P nuclear magnetic resonance, X-ray photoelectron spectroscopy, X-ray diffraction, and K-edge X-ray absorption near-edge structure techniques were used to analyze the P species in pig manure biochar (PMB). The results indicated that most of the organic P in the pig manure was converted to inorganic P during pyrolysis. Moreover, the transformation to different P groups pathways was clarified. The phase transition from amorphous to crystalline calcium phosphate was promoted when the temperature was above 600 °C. The content of P extracted by hydrochloric acid, which was the long-term available P for plant uptake, increased significantly. PMB pyrolyzed at 600 °C can be used as a highly effective substitute for P source. It provides the necessary P species (e.g. water-soluble P.) and metal elements for the growth of water spinach plants, and which are slow-release comparing with the Hogland nutrient solution.


Assuntos
Esterco , Pirólise , Animais , Suínos , Hidroponia , Fósforo/química , Carvão Vegetal/química
4.
Opt Lett ; 48(20): 5351-5354, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37831865

RESUMO

Computer-generated holography based on neural network holds great promise as a real-time hologram generation method. However, existing neural network-based approaches prioritize lightweight networks to achieve real-time display, which limits their capacity for network fitting. Here, we propose an asymmetrical neural network with a non-end-to-end structure that enhances fitting capacity and delivers superior real-time display quality. The non-end-to-end structure decomposes the overall task into two sub-tasks: phase prediction and hologram encoding. The asymmetrical design tailors each sub-network to its specific sub-task using distinct basic net-layers rather than relying on similar net-layers. This method allows for a sub-network with strong feature extraction and inference capabilities to match the phase predictor, while another sub-network with efficient coding capability matches the hologram encoder. By matching network functions to tasks, our method enhances the overall network's fitting capacity while maintaining a lightweight architecture. Both numerical reconstructions and optical experiments validate the reliability and effectiveness of our proposed method.

5.
JAMA Ophthalmol ; 141(2): e225555, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36795105

RESUMO

This case report discusses a diagnosis of morning glory syndrome and concurrent Bergmeister papilla and retinal detachment in a child aged 3 years.


Assuntos
Disco Óptico , Vítreo Primário Hiperplásico Persistente , Descolamento Retiniano , Humanos , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/cirurgia , Nervo Óptico , Síndrome
6.
Sci Total Environ ; 873: 162385, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36842598

RESUMO

Ammonia-oxidizing archaea (AOA) play an important role in natural nitrogen cycle, but are difficult to be enriched in wastewater treatment systems. In this experiment, under ambient temperature and high dissolved oxygen, different types of acyl-homoserine lactones (C6-HSL, C8-HSL, C10-HSL, C14-HSL and 3-oxo-C14-HSL) were added to five wastewater nitrification systems to achieve AOA enrichment. Results showed that AOA couldn't be detected in the blank group without the addition of signaling molecules, while the AOA could be detected in all the reactors with the addition. The enrichment effect of AOA was not obvious with added 100 or 200 nmol/L signaling molecules, while the enrichment effect was both obvious with added C8-HSL of 400 nmol/L and C10-HSL of 800 nmol/L. And relative abundance of AOA increased from undetected in the control group to 1.10 % and 0.96 %, respectively. The exogenous signaling molecules may provide new view for AOA enrichment in wastewater treatment systems.


Assuntos
Amônia , Archaea , Bactérias , Oxirredução , Percepção de Quorum , Nitrificação
10.
J Environ Manage ; 328: 116992, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36502703

RESUMO

The nitrogen removal performance of anaerobic ammonia oxidation granular sludge (AnGS) varies widely among particle sizes. In this paper, the nitrogen removal performance, extracellular polymeric substances (EPS) secretion level and microbial community of AnGS with different particle sizes were investigated to select the optimal particle size for different substrate concentrations. The results showed that the optimal particle size migrated from 0.6-1.6 mm to 1.6-2.5 mm and then to 2.5-3.2 mm as the substrate concentration increased. When the influent concentration of NH4+-N was 110 mg/L, granular sludge with particle size of 1.6-2.5 mm showed excellent nitrogen removal performance with the highest EPS secretion, while the highest EPS secretion gradually migrated to smaller particles as the substrate concentration decreased. The nitrogen removal performance of AnGS with different particle sizes depends on different proportions of anaerobic ammonium-oxidizing (anammox) bacteria (Candidates_Jettenia, Candidates_Kuenenia, Candidatus_Brocadia), heterotrophic nitrification aerobic denitrifying bacteria (Acinetobacter) and denitrifying bacteria (Denitratisoma). The optimum particle size range for AnGS has been clarified for different influent nitrogen concentrations, which can provide some new understanding for the application of anammox reactors.


Assuntos
Oxidação Anaeróbia da Amônia , Esgotos , Tamanho da Partícula , Desnitrificação , Oxirredução , Reatores Biológicos/microbiologia , Anaerobiose , Nitrogênio/química , Amônia/química
12.
Sci Rep ; 12(1): 9360, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672436

RESUMO

Baseline left ventricular (LV) dysfunction is associated with subsequent risks of acute kidney injury (AKI) and mortality in patients with sepsis. This study investigated the therapeutic effects of continuous renal replacement therapy (CRRT) in hemodynamically unstable patients with severe sepsis and septic shock combined with LV dysfunction. In this multicenter retrospective study, severe sepsis and septic shock patients with LV dysfunction were classified into one of two groups according to the timing of CRRT: the early group (before AKI was detected) or the control group (patients with AKI). Patients from the control group received an accelerated strategy or a standard strategy of CRRT. The primary outcome was all-cause intensive care unit (ICU) mortality. Patients were weighted by stabilized inverse probability of treatment weights (sIPTW) to overcome differences in baseline characteristics. After sIPTW analysis, the ICU mortality was significantly lower in the early group than the control group (27.7% vs. 63.5%, p < 0.001). Weighted multivariable analysis showed that early CRRT initiation was a protective factor for the risk of ICU mortality (OR 0.149; 95% CI 0.051-0.434; p < 0.001). The ICU mortality was not different between the accelerated- and standard-strategy group (52.5% vs. 52.9%, p = 0.970). Early CRRT in the absence of AKI is suggested for hemodynamically unstable patients with severe sepsis and septic shock combined with LV dysfunction since it benefits survival outcomes.


Assuntos
Injúria Renal Aguda , Terapia de Substituição Renal Contínua , Sepse , Choque Séptico , Disfunção Ventricular Esquerda , Humanos , Unidades de Terapia Intensiva , Estudos Retrospectivos , Sepse/complicações , Sepse/terapia , Choque Séptico/complicações , Choque Séptico/terapia , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/terapia
13.
Am J Ophthalmol Case Rep ; 25: 101276, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35146182

RESUMO

PURPOSE: We report a rare case of recurrent Descemet's membrane detachment (DMD) post-trabeculectomy which was resolved spontaneously without surgical intervention. OBSERVATIONS: A 66-year-old patient with a history of acute angle closure glaucoma in his right eye presented to our hospital. The intraocular pressure (IOP) of his right was 40 mm Hg, and the visual acuity was10/20. After trabeculectomy of the affected eye, a severe Descemet's membrane detachment was found by AS-OCT. Part of Descemet's membrane was lying in front of the iris and lens. Surgical repair was performed, and viscoelastics and sterile air were injected into the anterior chamber to return the detached Descemet's membrane. AS-OCT showed that the DMD was successfully resolved. However, on the 7th day of follow-up, the DMD was detached again as seen on AS-OCT images. The patient refused reoperation to repair the DMD. Six months later, the patient visited our hospital again, and, interestingly, the DMD was completely resolved spontaneously without reoperation. CONCLUSIONS AND IMPORTANCE: Descemet's membrane is the basement membrane that lies between the stroma and the endothelial layer of the cornea. Minor DMD may be resolved spontaneously within a period of time without surgery, but large DMD is difficult to recover spontaneously. We believe that this is a rare case with spontaneous recovery of extensive DMD after trabeculectomy. But, despite all this, we still remain of the view that DMD should be treated immediately once it occurs.

14.
Perfusion ; 37(2): 175-187, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33475032

RESUMO

INTRODUCTION: Left ventricular diastolic dysfunction (LVDD) adversely impacts renal function, and E/e' is a significant predictor of adverse kidney events under different clinical conditions. However, no studies have evaluated the association between LVDD and septic acute kidney injury (AKI) among patients with severe sepsis and septic shock. METHODS: This multicenter retrospective study evaluated adult patients with severe sepsis or septic shock between January 1, 2013, and December 31, 2019, who underwent echocardiography within 24 hours after admission to an intensive care unit. RESULTS: A total of 495 adult patients were enrolled in the study. LVDD grades II and III were associated with severe (stage 3) AKI (p < 0.001, p for trend < 0.001). E/e' and e' were risk factors for septic AKI (OR, 1.155; 95% CI, 1.088-1.226, p < 0.001; and OR, 7.218; 95% CI, 2.942-17.712, p < 0.001, respectively) in the multivariate logistic regression analysis. The area under the receiver operating characteristic curve of E/e' and e' was 0.728 (95% CI, 0.680-0.777, p < 0.001) and 0.715 (95% CI, 0.665-0.764, p < 0.001), respectively. CONCLUSIONS: LVDD was associated with septic AKI, and E/e' and e' are useful predictors of septic AKI among patients with severe sepsis or septic shock. TRIAL REGISTRATION: The study was registered at the Chinese Clinical Trial Registry (Protocol No. ChiCTR2000033083).


Assuntos
Injúria Renal Aguda , Sepse , Choque Séptico , Disfunção Ventricular Esquerda , Injúria Renal Aguda/complicações , Adulto , Humanos , Estudos Retrospectivos , Sepse/complicações , Choque Séptico/complicações , Disfunção Ventricular Esquerda/complicações
15.
Waste Manag ; 134: 241-250, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34454190

RESUMO

Biomass waste is a desirable additive in livestock feces biochar preparation due to its easy access, better moisture adjustment, and abundant organic content. In the present study, co-pyrolysis of livestock feces (PM: pig manure, CM: chicken manure) and biomass wastes (WC: wood chips, BS: bamboo sawdust, RH: rice husk, and CH: chaff) with different blending ratios was conducted at 600 °C to investigate the biochar characteristic and Cu/Zn immobilization performances. The results showed that WC and BS have more significant effect on the increase in fixed carbon content and heating value and the decrease in ash content of biochar. The biochar with lower pH and electrical conductivity is obtained from co-pyrolysis of manure with RH and CH. Compared with CM-based biochar, PM-based biochar presented better potential as fuel and soil remediation considering the higher heating value and lower aromatic H/C ratio. Specially, the residual fractions of Cu and Zn in PM biochar increased from 73.09% and 65.54% to 90.68% and 72.31% after 10 wt% BS addition and those in CM biochar increased from 81.07% and 73.57% to 88.87% and 84.11% after 10 wt% WC addition, which induced the lowest environmental risk of biochar. This work provided a strategy and direction for targeted enhancement in biochar characteristics with selective biomass addition during manure pyrolysis, which is beneficial to the local treatment and utilization of farm wastes.


Assuntos
Metais Pesados , Pirólise , Animais , Biomassa , Carvão Vegetal , Fezes , Gado , Suínos
16.
Environ Sci Pollut Res Int ; 28(47): 67120-67136, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34245419

RESUMO

Sulfur compound detection such as mercaptans in liquid fuels is undesirable because sulfur is the main sourcing emission of sulfur oxide (SOx) into the air. The use of activated carbon (AC) has proven to efficiently remove mercaptans. In the meantime, it is limited by the generation of the second pollution in oil and the difficulties of recovery and regeneration. A core-shell structured AC with high mechanical strength and big intra-particles space was synthesized and demonstrated to efficiently remove organic pollutants from an aqueous solution without the generation of the second pollution in our previous work. However, the performance and behaviors of mercaptans adsorption from gasoline oil by core-shell structured AC were still unclear. In this study, the mercaptans adsorption behaviors using core-shell powdered activated carbon (CSAC) and core-shell granulated activated carbon (CSGAC), along with raw PAC, PAC-core, raw GAC, and GAC-core, were carried out. The results showed that both the CSAC and CSGAC adsorbents effectively removed sulfur-based pollutants and were provided with good recovery and recyclability without second pollution in gasoline oil. The CSGAC exhibited a higher mercaptans removal efficiency compared to those of CSAC as a result of the bigger intra-particles space. PAC-based adsorbents presented the shrinking of removal efficiency after regeneration. The pseudo-second-order kinetic model was dominated for mercaptans adsorption by both CSAC and CSGAC. The adsorption of ethanethiol on CSGAC was better fitted to the Freundlich model, 1-butanethiol adsorption by CSAC and CSGAC, and ethanethiol adsorption on CSAC which was dominated by Langmuir model.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Adsorção , Gasolina , Cinética , Compostos de Sulfidrila , Poluentes Químicos da Água/análise
17.
Water Res ; 201: 117385, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34225234

RESUMO

Soot nanoparticles (SNPs) undergo aging processes in aqueous systems, altering their physicochemical properties and affecting their fate and transport. This study investigated the aging effects via ultraviolet irradiation on aggregation kinetics of SNPs in water. The results showed that, compared to fresh SNPs, those irradiated for 1 day aggregated more easily in NaCl and CaCl2 solutions, with reduction of critical coagulation concentrations by 72% and 40%, respectively. Similar phenomena were found in additional six electrolyte solutions, and SNPs irradiated for > 3 days had no measurable difference in aggregation rate. The aggregation-enhancement of irradiated SNPs was more prominent at low electrolyte concentrations and pH > 4. However, in the presence of macromolecules, irradiated SNPs could be stabilized against aggregation via steric hindrance with strength of bovine serum albumin > humic acid > alginate > fulvic acid, whereas alginate further destabilized aged SNPs via calcium bridging. The fitted Hamaker constant increased from 7.8 × 10-20 (fresh) to 1.2 × 10-19 J (7-day irradiated), suggesting that decarboxylation during irradiation may weaken electrical repulsion and enhance van der Waals attraction, promoting aggregation. These results demonstrated the vital role of UV-induced aging in fate and transport of SNPs in wet environments.


Assuntos
Nanopartículas , Fuligem , Substâncias Húmicas/análise , Cinética , Soluções
18.
Sci Total Environ ; 790: 147972, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34082326

RESUMO

The coupling removal of acid volatile sulfide (AVS), ferrous iron, and ammonia nitrogen has been applied for black-odorous sediment remediation. In this study, calcium nitrate with different N/(S + Fe) ratios (0.45, 0.90, 1.20 and 1.80) was added into black-odorous sediment in four systems named R1, R2, R3, and R4. Results showed that the removal rate of AVS was 76.40% in the R1, which was lower compared with rates in R2-R4 around 96.70%. The ferrous oxidation rate was approximately 87.00% in R2-R4, which was considerably higher than that in the R1 (24.62%). And the ammonia was reduced by 81.02%, 88.00%, 100%, and 57.18% in R1, R2, R3 and R4, respectively. During the reaction, nitrite accumulation was observed, indicating partial denitrification. Moreover, microbes related to autotrophic denitrification (e.g., genus Thiobacillus, Dok59, GOUTA19, Gallionella, with the highest abundance of 15.40%, 13.21%, 8.79%, 9.44%, respectively) were detected in all systems. Furthermore, the anammox bacteria Candidatus_Brocadia with the highest abundance of 3.44% and 4.00% in R2 and R3, respectively was also found. These findings confirmed that AVS, ferrous iron, and ammonia nitrogen could be simultaneously removed via autotrophic denitrification coupled with anammox in black-odorous sediment by nitrate addition.


Assuntos
Amônia , Desnitrificação , Reatores Biológicos , Ferro , Nitratos , Nitrogênio , Oxirredução , Sulfetos
19.
Water Sci Technol ; 83(10): 2424-2436, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34032620

RESUMO

Using solid adsorbents, such as biochar, has been a potential practice to remove the pollutants from water bodies to render the water safer for potential usage. A potential application of sludge biochar-based adsorbent (SBA), obtained by pyrolysis with hydrothermal treatment, was developed to adsorb Direct Red 23 (DR23) from wastewater. The results showed that for the synthesized SBA (0.5 g/L) in the adsorption of DR23 at low concentration (<20 mg/L), the DR23 was totally removed from the aqueous solution. pH had a limited effect on the adsorption, while an increase in temperature was shown to have a large enhancing effect. The adsorption kinetics were best fitted by the pseudo-second-order kinetic model, while the equilibrium data were best fitted by the Langmuir isotherm. A maximum saturation adsorption capacity of SBA of 111.98 mg/g was achieved. SBA could then be regenerated by pyrolysis, and after three cycles, SBA still retained good adsorption ability for DR23, a removal rate exceeding 97% was achieved. Functional groups, pores, π-π bond, and electrostatic interactions are the key to the adsorption mechanisms. The results proved that SBA would be a promising material in the application of removing dyes in printing and dyeing wastewater.


Assuntos
Esgotos , Poluentes Químicos da Água , Adsorção , Anilidas , Compostos Azo , Carvão Vegetal , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica , Poluentes Químicos da Água/análise
20.
RSC Adv ; 11(14): 7897-7902, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35423307

RESUMO

We modified the conventional etching-optical method to measure dislocation direction in a KDP crystal. As burgers vector of dislocation in the KDP crystal must match the minimum periodic vector of the crystal lattice, we suggest that dislocations with a burgers vector of [101], [102] and [103] exist. Atomic force microscopy was employed to characterize the morphology of growth spirals on the hillock of (101) faces. Multi-spirals consisting of more than two element steps with a height of 0.5 nm which is equal to (101) face interplanar distances were observed. We propose the multi-spiral structure is determined by the burgers vector of the corresponding dislocation, and constructed a geometric model of the crystal with screw dislocation to derive the relationship. Growth spirals on the (101) face present a particular triangular morphology and we proved that the triangle structure is formed by connected steps in the 1/2[111] and [010] direction. Micropipes form when the magnitude of the dislocation's burgers vector exceeds 1 nm, as predicted by BCF theory. Interaction between dislocations was observed also.

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