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1.
Environ Res ; 213: 113716, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35718165

RESUMEN

Understanding of mechanisms in nitrous oxide (N2O) emission from constructed wetland (CW) is particularly important for the establishment of related strategies to reduce greenhouse gas (GHG) production during its wastewater treatment. However, plant biomass accumulation, microbial communities and nitrogen transformation genes distribution and their effects on N2O emission from CW as affected by different nitrogen forms in aquatic environment have not been reported. This study investigated the interactive effects of aquatic nitrogen and plant biomass on N2O emission from subsurface CW with NH4+-N (CW-A) or NO3--N (CW-B) wastewater. The experimental results show that NH4+-N and NO3--N removal efficiencies from CW mesocosms were 49.4% and 87.6%, which indirectly lead to N2O emission fluxes of CW-A and CW-B maintained at 213 ± 67 and 462 ± 71 µg-N/(m2·h), respectively. Correlation analysis of nitrogen conversion dynamic indicated that NO2--N accumulation closely related to N2O emission from CW. Aquatic NH4+-N could up-regulate plant biomass accumulation by intensifying citric acid cycle, glycine-serine-threonine metabolism etc., resulting in more nitrogen uptake and lower N2O emission/total nitrogen (TN) removal ratio of CW-A compared to CW-B. Although the abundance of denitrifying bacteria and N2O reductase nosZ in CW-B were significantly higher than that of CW-A, after fed with mixed NH4+-N and NO3--N influent, N2O fluxes and N2O emission/TN removal ratio in CW-A were extremely close to that of CW-B, suggesting that nitrogen form rather than nitrogen transformation microbial communities and N2O reductase nosZ determines N2O emission from CW. Hence, the selection of nitrate-loving plants will play an important role in inhibiting N2O emission from CW.


Asunto(s)
Óxido Nitroso , Humedales , Biomasa , Desnitrificación , Nitrógeno/metabolismo , Oxidorreductasas/metabolismo , Plantas/metabolismo
2.
J Environ Manage ; 306: 114489, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35051820

RESUMEN

The dynamic interactions among iron (Fe) oxides, dissolved organic matter (DOM) and toxic trace metals play crucial roles in risk assessment and environmental remediation. Although the inhibitory effects of DOM on the iron oxides transformation process have been studied previously, there is still a lack of mechanistic and quantitative understanding on the kinetics of Cr(VI) and ferrihydrite transformation in the present of DOM. In this study, we investigated the fractionation process of DOM on ferrihydrite and its influence on the fate of Cr(VI) and transformation of ferrihydrite. The result of three-dimension excitation emission matrix (3D-EEM), Q-Exactive LC-MS/MS, X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM) indicated that fulvic acid-like compounds of DOM were the mainly fractionated compounds on the surface of ferrihydrite, which further inhibited the transformation of ferrihydrite. Besides, bracewellite (CrO(OH)) generated as an accompanied mineral during the transformation of ferrihydrite in the present of Cr(VI). Based on the DFT theoretical calculation, we concluded that Cr(VI) mainly in the form of HCr O4- was more inclined to be adsorbed on iron-oxide tetrahedron by inner-sphere monodentate mononuclear configurations. The findings on the dynamic coupling among Fe oxide transformation and Cr(VI) sequestration under the effect of DOM provided the basis for accurately predicting the fate of trace elements and iron mineral.


Asunto(s)
Materia Orgánica Disuelta , Espectrometría de Masas en Tándem , Cromatografía Liquida , Cromo , Compuestos Férricos , Oxidación-Reducción
3.
Opt Express ; 29(24): 40481-40493, 2021 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-34809387

RESUMEN

We report a systematic study of the optical absorption of twisted bilayer graphene (tBLG) across a large range of twist angles from 0° to 30° using a high-resolution reflectance confocal laser microscopy (RCLM) system. The high-quality single crystalline tBLG was synthesized via the efficient plasma enhanced chemical vapor deposition techniques without the need of active heating. The sensitivity of acquired images from the RCLM were better than conventional optical microscopes. Although the highest spatial resolution of RCLM is still lower than scanning electron microscopes, it possesses the advantages of beam-damage and vacuum free. Moreover, the high intensity-resolution (sensitivity) images firstly allowed us to distinguish the slight absorption differences and analyze the correlation between the optical absorption and twisted angle of tBLG after data processing procedures. A maximum absorption (minimum transmission) was observed at the stacking angle of tBLG from 10° to 20°, indicating the interplay between the laser and the electron/hole van-Hove singularities when tBLG oriented around the critical angle (θc∼13°). The twisted angle correlated optical absorption paves an alternative way not only to visibly identify the interlayer orientation of tBLG but also to reflect the characterization of the interlayer coupling via its band structure.

4.
Chem Soc Rev ; 48(14): 3811-3841, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31179451

RESUMEN

Metal/covalent-organic framework (MOF/COF) membranes have attracted increasing research interest and have been considered as state-of-the-art platforms applied in various environment- and energy-related separation/transportation processes. To break the trade-off between permeability and selectivity to achieve ultimate separation, recent studies have been oriented towards how to design and exploit ultrathin MOF/COF membranes (i.e. sub-1 µm-thick). Given great advances made in the past five years, it is valuable to timely and systematically summarize the recent development and shed light on the future trend in this multidisciplinary field. In this review, we first present the advanced strategies in fabricating ultrathin defect-free MOF/COF membranes such as in situ growth, contra-diffusion method, layer-by-layer (LBL) assembly, metal-based precursor as the pre-functionalized layer, interface-assisted strategy, and laminated assembly of MOF/COF nanosheets. Then, the recent progress in some emerging applications of ultrathin MOF/COF membranes beyond gas separation is highlighted, including water treatment and seawater desalination, organic solvent nanofiltration, and energy-related separation/transportation (i.e. lithium ion separation and proton conductivity). Finally, some unsolved scientific and technical challenges associated with future perspectives in this field are discussed, inspiring the development of next-generation separation membranes.

5.
Langmuir ; 35(10): 3643-3650, 2019 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-30773014

RESUMEN

Deposition of dopamine and tannic acid has received great attention in the fields of surface and interface science and technology. The deposition behaviors of various metal-phenolic systems have been investigated, and it is generally accepted that at least one catechol group is essential to the formation of the coatings. Herein, we report a novel and effective surface-coating system based on the coordination complexes of FeIII ions with a natural product juglone that contains only one phenolic hydroxyl. We investigated the deposition behaviors of this novel system on various substrates. Microporous polypropylene membrane modified with juglone/FeIII coatings is superhydrophilic and underwater superoleophobic, showing high separation efficiency and good reusability for various oil/water emulsions. In addition, the modified membrane can adsorb anionic dyes and selectively remove them from dye mixtures with high efficiency. We further demonstrated that the coating is a result of the synergetic effect of juglone/FeIII coordination and FeIII hydrolysis. This work not only provides new insights into surface deposition systems but also expands the polyphenol family for surface coatings of multifunctional materials.

6.
Angew Chem Int Ed Engl ; 57(38): 12328-12332, 2018 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-30074668

RESUMEN

Sterically hindered substrates can be employed in an enantioselective palladium-catalyzed α-arylation with the chiral monophosphorus ligand BI-DIME. This process enabled an efficient synthesis of the antidepressant (S)-nafenodone, a four-step enantioselective synthesis of the Sceletium alkaloid (+)-sceletium A-4, a concise five-step enantioselective synthesis of (-)-corynoline, as well as a three-step preparation of (-)-DeN-corynoline.

7.
Chemistry ; 21(45): 16035-46, 2015 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-26403796

RESUMEN

As opposed to the reversible redox reaction ({Fe(NO)2 }(10) reduced-form DNIC [(NO)2 Fe(S(CH2 )3 S)](2-) (1)⇌{Fe(NO)2 }(9) oxidized-form [(NO)2 Fe(S(CH2 )3 S)](-) ), the chemical oxidation of the {Fe(NO)2 }(10) DNIC [(NO)2 Fe(S(CH2 )2 S)](2-) (2) generates the dinuclear {Fe(NO)2 }(9) -{Fe(NO)2 }(9) complex [(NO)2 Fe(µ-SC2 H4 S)2 Fe(NO)2 ](2-) (3) bridged by two terminal [SC2 H4 S](2-) ligands. On the basis of the Fe K-edge pre-edge energy and S K-edge XAS, the oxidation of complex 1 yielding [(NO)2 Fe(S(CH2 )3 S)](-) is predominantly a metal-based oxidation. The smaller S1-Fe1-S2 bond angle of 94.1(1)° observed in complex 1 (S1-Fe1-S2 88.6(1)° in complex 2), compared to the bigger bond angle of 100.9(1)° in the {Fe(NO)2 }(9) DNIC [(NO)2 Fe(S(CH2 )3 S)](-) , may be ascribed to the electron-rich {Fe(NO)2 }(10) DNIC preferring a restricted bite angle to alleviate the electronic donation of the chelating thiolate to the electron-rich {Fe(NO)2 }(10) core. The extended transition state and natural orbitals for chemical valence (ETS-NOCV) analysis on the edt-/pdt-chelated {Fe(NO)2 }(9) and {Fe(NO)2 }(10) DNICs demonstrates how two key bonding interactions, that is, a FeS covalent σ bond and thiolate to the Fe d z 2 charge donation, between the chelating thiolate ligand and the {Fe(NO)2 }(9/10) core could be modulated by the backbone lengths of the chelating thiolate ligands to tune the electrochemical redox potential (E1/2 =-1.64 V for complex 1 and E1/2 =-1.33 V for complex 2) and to dictate structural rearrangement/chemical transformations (S-Fe-S bite angle and monomeric vs. dimeric DNICs).

8.
Reprod Sci ; 31(2): 366-374, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37749447

RESUMEN

Patients with Idiopathic non-obstructive azoospermia (iNOA) can achieve fertility by extracting testicular sperm through microdissection testicular sperm extraction (mTESE). But more than half of iNOA patients still cannot benefit from mTESE. In recent years, some studies had reported that serum hormones may be related to the outcome of sperm retrieval, but few had been verified. We hope to obtain a predictive method that is convenient for clinical application and can help judge the outcome of sperm extraction before implementing mTESE. We performed a retrospective analysis of NOA patients who underwent mTESE in the same andrology center from June 2020 to November 2022. A total of 261 patients with complete data were collected, logistic regression analysis was performed and a predictive model was constructed. Then, from December 2022 to May 2023, one prospective cohort of 48 NOA patients who met the inclusion criteria from the same center was recruited to validate the risk prediction model. We successfully constructed a logistic regression model to predict the outcome of iNOA patients undergoing mTESE and found that higher serum anti-Müllerian hormone (AMH) levels were associated with failure sperm retrieval, resulting in an AMH cut-off of 2.60 ng/ml. The area under the receiver operating curve was 0.811, the sensitivity was 0.870, and the specificity was 0.705. Decision curve analysis demonstrated that the threshold probability was above 4%, and unnecessary mTESE could be reduced using this model. In a prospective cohort at the same center, 85.42% (41/48) of iNOA patients correctly identified the mTESE outcome using this model. A logistic regression model with AMH as an independent predictor can predict mTESE outcomes in iNOA patients. Preoperative selection of mTESE in patients with iNOA using this model had clinical benefit in reducing unnecessary surgery. The model demonstrated good accuracy in a small prospective cohort validation.


Asunto(s)
Azoospermia , Humanos , Masculino , Azoospermia/diagnóstico , Azoospermia/cirugía , Estudios Retrospectivos , Microdisección/métodos , Estudios Prospectivos , Recuperación de la Esperma , Semen , Testículo/cirugía , Espermatozoides
9.
Medicine (Baltimore) ; 103(8): e37201, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38394502

RESUMEN

BACKGROUND: Testicular cancer (TC) mostly occurs in men aged 14 to 44. Studies have shown that TC seriously damages male fertility, and 6% to 24% of patients with TC were even found to suffer from azoospermia when they are diagnosed. At present, some studies have pointed out that onco-microdissection testicular sperm extraction (mTESE) can extract sperm from tumor testicles. However, there are almost no reports on remedial measures after onco-mTESE failure. Given the valuable opportunity for fertility preservation in patients with TC and azoospermia, it is necessary to provide effective remedial methods for patients with failed onco-mTESE. METHODS: Two young men, who were diagnosed with TC and also found to have azoospermia, tried onco-mTESE while undergoing radical orchiectomy for fertility preservation. However, sperm extraction failed in both patients. Subsequently, the isolated testicular tissue of the patient in case 1 suffered from TC again, and the patient in case 2 was scheduled to receive multiple cycles of gonadotoxic chemotherapy. Because both had a plan to have a birth in the future, we performed remedial mTESE. RESULTS: Sperm was successfully extracted from both patients. The patient recovered well, without complications. The patient couple in case 1 underwent 1 intracytoplasmic sperm injection (ICSI) cycle but did not achieve clinical pregnancy. CONCLUSIONS: There is still an opportunity to extract sperm successfully using onco-mTESE, despite the difficulty of fertility preservation in TC patients with azoospermia. If sperm extraction from the tumor testis fails, implementing remedial mTESE as early as possible would likely preserve the last chance of fertility for these patients.


Asunto(s)
Azoospermia , Neoplasias de Células Germinales y Embrionarias , Neoplasias Testiculares , Embarazo , Femenino , Humanos , Masculino , Azoospermia/terapia , Azoospermia/complicaciones , Neoplasias Testiculares/cirugía , Neoplasias Testiculares/complicaciones , Microdisección/métodos , Recuperación de la Esperma , Semen , Espermatozoides/patología , Estudios Retrospectivos , Testículo/cirugía , Testículo/patología
10.
Heliyon ; 7(11): e08333, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34816037

RESUMEN

INTRODUCTION: Wildfire smoke (WFS) exposure is a growing threat to human health, and lower socioeconomic position (SEP) has been shown to increase pollution susceptibility. Studies of SEP-related susceptibility, however, are often compromised due to spatial confounding between lower-SEP and pollution. Here we examine outdoor-housed nonhuman primates, living in natural social hierarchy in a common location, born during years of high vs. low WFS, to examine the separate and combined effects of WFS and social rank, an analog to SEP, on lung and immune function. METHODS: Twenty-one females were born during extreme WFS events in summer 2008; 22 were born in summer 2009, during low WFS. Pulmonary function and circulating cytokines were measured three years later, in adolescence. We estimated fine particulate (PM2.5) and ozone exposures during each animal's first 90 days and three years of age using regulatory data. Early-life social status was estimated using maternal rank at birth, as rank in females is relatively stable throughout life, and closely approximates mother's rank. We tested associations among WFS exposure, rank, and endpoints using linear regression and ANOVA. RESULTS: Higher WFS exposure in infancy was, on average, associated with lower functional residual capacity (FRC), residual volume (RV), tissue compliance (Ct), and IL-8 secretion in adolescence. Higher social rank conferred significantly higher expiratory reserve volume (ERV) and functional residual capacity (FRC) solely among those born in the high-WFS year (2008). Differences in effects of rank between years were not significant after adjustment for multiple comparisons. CONCLUSIONS: Exposure to WFS in infancy generally conferred lower adolescent respiratory volumes and inflammatory cytokines. Higher rank conferred higher respiratory volumes only among females born during WFS, suggesting the possibility that the health benefits of rank may be more apparent under environmental challenge.

11.
Org Lett ; 22(12): 4602-4607, 2020 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-32484358

RESUMEN

We herein report the development of a sterically hindered and electron-rich P-chiral monophosphorus biaryl ligand that has enabled a general and efficient enantioselective intramolecular α-arylation, providing access to a wide series of [4.4], [4.5], and [4.6]-spirocycles with chiral benzylic quaternary carbons in high yields with good to excellent enantioselectivities. A pronounced water effect on enantioselectivity is observed.

12.
Water Res ; 150: 340-348, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30530128

RESUMEN

The frequent occurrence of polycyclic aromatic hydrocarbons (PAHs) in aquatic environments is of great concern because of their teratogenicity, toxicity, carcinogenicity, and mutagenicity to plants, animals and human beings. In this study the bioelectricity generation, biodegradation, phytoextraction and substrate adsorption of phenanthrene and anthracene in a constructed wetland-microbial fuel cell (CW-MFC) were investigated with an anode electrode amended with or without biochar-nZVI. During a 182-day operation period, the average removal efficiency for phenanthrene and anthracene ranged from 88.5% to 96.4%. The concentration of phenanthrene in roots, stems and laminas of T. orientalis was 14.9, 3.9 and 2.3 ng g-1 respectively, while that of anthracene was 22.2, 3.1 and 1.3 ng g-1, respectively. In addition, the application of nZVI was conducive to bioelectricity generation and organic compound degradation in the CW-MFC reactor. The distribution of the bacterial community indicated that the relative abundance of Bacillus, Paludibacter, Desulfovibrio and Lactococcus with a degradation capability for refractory organics was significantly increased. Especially the genus Bacillus for excreting catalase became more abundant. The results of our study indicate how to promote bioelectricity generation and biodegradation of refractory organic compounds in a CW-MFC by improving the culture conditions for bacteria.


Asunto(s)
Fuentes de Energía Bioeléctrica , Fenantrenos , Antracenos , Electrodos , Humedales
13.
Sci Data ; 6(1): 219, 2019 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-31641130

RESUMEN

As basic data, the river networks and water resources zones (WRZ) are critical for planning, utilization, development, conservation and management of water resources. Currently, the river network and WRZ of world are most obtained based on digital elevation model data automatically, which are not accuracy enough, especially in plains. In addition, the WRZ code is inconsistent with the river network, hindering the efficiency of data in hydrology and water resources research. Based on the global 90-meter DEM data combined with a large number of auxiliary data, this paper proposed a series of methods for generating river network and water resources zones, and then obtained high-precision global river network and corresponding WRZs at level 1 to 4. The dataset provides generated rivers with high prevision and more accurate position, reasonable basin boundaries especially in inland and plain area, also the first set of global WRZ at level 1 to 4 with unified code. It can provide an important basis and support for reasonable use of water resources and sustainable social development in the world.

14.
Bioresour Technol ; 245(Pt A): 372-378, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28898833

RESUMEN

Integrating microbial fuel cell with constructed wetland (CW-MFC) is a novel way to harvest bioelectricity during wastewater treatment. In this study, the bioelectricity generation, containment removal and microbial community distribution in CW-MFC as affected by substrate material sizes and aquatic macrophyte were investigated. The planted CW-MFC with larger filler size showed a significant promotion of the relative abundance of electrochemically active bacteria (beta-Proteobacteria), which might result in the increase of bioelectricity generation in CW-MFC (8.91mWm-2). Additionally, a sharp decrease of voltage was observed in unplanted CW-MFC with smaller filler size in Cycle eight. However, the peak COD (86.7%) and NO3-N (87.1%) removal efficiencies were observed in planted CW-MFC with smaller filler size, which was strongly related to the biodiversity of microorganisms. Generally, the acclimation of exoelectrogens as dominant microbes in the anode chamber of planted CW-MFC with larger filler size could promote the bioelectricity generation during wastewater treatment.


Asunto(s)
Fuentes de Energía Bioeléctrica , Aguas Residuales , Humedales , Bacterias , Electricidad , Electrodos
15.
ACS Appl Mater Interfaces ; 9(39): 34356-34366, 2017 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-28893062

RESUMEN

Surface modification has been well recognized as a promising strategy to design and exploit diversified functional materials. However, conventional modification strategies usually suffer from complicated manufacture procedures and lack of universality. Herein, a facile, robust, and versatile approach is proposed to achieve the surface functionalization using dopamine and acrylate monomers via a one-step polymerization and codeposition process. The gel permeation chromatography, proton nuclear magnetic resonance, liquid chromatography-mass spectrometry, and UV-visible spectra results indicate that dopamine possesses the capability of triggering the polymerization of acrylate monomers into high-molecular-weight products, and the inherent adhesive ability of polydopamine can assist the polymerized products to deposit on various substrates. Besides, protein-resistant, antibacterial, and cell adhesion-resistant surfaces can be easily fabricated via the finely designed integration of corresponding acrylate monomers into the codeposition systems. This approach of in situ polymerization and codeposition significantly simplifies the fabrication process and provides more manifold choices for surface modification, which will open a new door for broadening the applications of polydopamine-based coatings.


Asunto(s)
Dopamina/química , Acrilatos , Antibacterianos , Adhesión Celular , Polimerizacion , Polímeros
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