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1.
Environ Pollut ; 360: 124615, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39059700

RESUMO

Atmospheric fine particulate matter (PM2.5) can trigger the production of cytotoxic reactive oxygen species (ROS), which can trigger or exacerbate oxidative stress and pulmonary inflammation. We collected 111 daily (∼24 h) ambient PM2.5 samples within an urban region of North China during four seasons of 2019-2020. PM2.5 samples were examined for carbonaceous components, water-soluble ions, and elements, together with their oxidative potential (represent ROS-producing ability) by DTT assay. The seasonal peak DTTv was recorded in winter (2.86 ± 1.26 nmol min-1 m-3), whereas the DTTm was the highest in summer (40.6 ± 8.7 pmol min-1 µg-1). WSOC displayed the highest correlation with DTT activity (r = 0.84, p < 0.0001), but the influence of WSOC on the elevation of DTTv was extremely negligible. Combustion source exhibited the most significant and robust correlation with the elevation of DTTv according to the linear mixed-effects model result. Source identification investigation using positive matrix factorization displayed that combustion source (36.2%), traffic source (30.7%), secondary aerosol (15.7%), and dust (14.1%) were driving the DTTv, which were similar to the results from the multiple linear regression (MLR) analysis. Backward trajectory analysis revealed that the major air masses originate from local and regional transportation, but PM2.5 OP was more susceptible to the influence of short-distance transport clusters. Discerning the influence of chemicals on health-pertinent attributes of PM2.5, such as OP, could facilitate a deep understanding of the cause-and-effect relationship between PM2.5 and impacts.

2.
Heliyon ; 10(13): e33937, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39055833

RESUMO

Chimeric antigen receptor (CAR)-T cell therapy has been confirmed improving remission rates in refractory patients or relapsed B-cell acute lymphoblastic leukemia (R/R B-ALL). However, the added benefits of undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) following CAR-T therapy remain a subject of debate. In this research we investigated the efficiency and long-term outcomes of CD19 CAR-T bridging with allo-HSCT in R/R B-ALL patients. A total of 42 patients were brought into the cohort studies. Our findings revealed that patients who appected CAR-T followed by HSCT had a 1-year overall survival (OS) rate of 70 % and a 1-year leukemia-free survival (LFS) rate of 95 %. Moreover, patients who underwent this combined treatment had higher OS and LFS rates compared to those who received CAR-T therapy alone. In conclusion, the results of this clinical trial provide compelling evidence for the safety and efficacy of using CAR-T therapy as a bridging strategy to allo-HSCT in patients with R/R B-ALL.

3.
Breast Cancer ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896170

RESUMO

BACKGROUND: A history of severe nausea and vomiting during pregnancy (SNVP) is a risk factor for postoperative nausea and vomiting (PONV). This study aimed to explore potentially effective treatment strategies and potential genetic factors underlying SNVP risk-related PONV. METHODS: A total of 140 female patients undergoing breast cancer surgery were assigned to either the study group (70 with SNVP) or the control group (70 with mild to moderate nausea and vomiting during pregnancy (MNVP)). Patients in each group were randomly assigned to two different treatment subgroups and received either ondansetron plus dexamethasone (OD) or OD + TEAS (ODT) (transcutaneous electrical acupoint stimulation, TEAS). Blood samples were collected from patients before induction (D0) and 24 h (D1) after surgery for growth differentiation factor 15 (GDF-15) evaluation. The primary outcome was the incidence of PONV within 36 h. The secondary outcome was the serum GDF-15 level. RESULTS: The incidence of PONV in the SNVP group was significantly higher than that in the MNVP group within 24 h (P < 0.005). In the SNVP group, ODT-treated patients had less PONV than those in the OD-treated group during the 6-12 h (P = 0.033) and 12-24 h (P = 0.008) intervals, while within 6 h, there were fewer vomiting cases in the ODT-treated group (SNVP-ODT vs. SNVP-OD, 7/33 vs. 19/35, P = 0.005). The preoperative GDF-15 serum levels in patients with SNVP were significantly higher (P = 0.004). Moreover, higher preoperative GDF-15 serum levels correlated with a higher incidence of PONV (P = 0.043). CONCLUSIONS: TEAS showed significant effect on PONV treatment in patients with SNVP. A higher serum GDF-15 level was associated with a history of SNVP, as well as a higher risk of PONV.

4.
Bioelectrochemistry ; 158: 108723, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38733720

RESUMO

Bidirectional electron transfer is about that exoelectrogens produce bioelectricity via extracellular electron transfer at anode and drive cytoplasmic biochemical reactions via extracellular electron uptake at cathode. The key factor to determine above bioelectrochemical performances is the electron transfer efficiency under biocompatible abiotic/biotic interface. Here, a graphene/polyaniline (GO/PANI) nanocomposite electrode specially interfacing exoelectrogens (Shewanella loihica) and augmenting bidirectional electron transfer was conducted by in-situ electrochemical modification on carbon paper (CP). Impressively, the GO/PANI@CP electrode tremendously improved the performance of exoelectrogens at anode for wastewater treatment and bioelectricity generation (about 54 folds increase of power density compared to blank CP electrode). The bacteria on electrode surface not only showed fast electron release but also exhibited high electricity density of extracellular electron uptake through the proposed direct electron transfer pathway. Thus, the cathode applications of microbial electrosynthesis and bio-denitrification were developed via GO/PANI@CP electrode, which assisted the close contact between microbial outer-membrane cytochromes and nanocomposite electrode for efficient nitrate removal (0.333 mM/h). Overall, nanocomposite modified electrode with biocompatible interfaces has great potential to enhance bioelectrochemical reactions with exoelectrogens.


Assuntos
Fontes de Energia Bioelétrica , Eletrodos , Grafite , Grafite/química , Transporte de Elétrons , Fontes de Energia Bioelétrica/microbiologia , Compostos de Anilina/química , Compostos de Anilina/metabolismo , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Shewanella/metabolismo , Nanocompostos/química , Técnicas Eletroquímicas/métodos
5.
Artigo em Inglês | MEDLINE | ID: mdl-38813648

RESUMO

The effectiveness of target temperature management (TTM) in poor-grade aneurysmal subarachnoid hemorrhage (aSAH) remains a topic of debate. In order to assess the clinical efficacy of TTM in patients with poor-grade aSAH, we conducted a systematic review and meta-analysis. This research was registered in PROSPERO (CRD42023445582) and included all relevant publications up until October 2023. We compared the TTM groups with the control groups in terms of unfavorable outcomes (modified Rankin scale [mRS] score > 3), mortality, delayed cerebral ischemia (DCI), cerebral vasospasm (CVS), and specific complications. Subgroup analyses were performed based on country, study type, follow-up time, TTM method, cooling maintenance period, and rewarming rate. Effect sizes were calculated as relative risk (RR) using random-effect or fixed-effect models. The quality of the articles was assessed using the methodological index for non-randomized studies scale. Our analysis included a total of 5 clinical studies (including 1 randomized controlled trial) and 219 patients (85 in the TTM group and 134 in the control group). Most of the studies were of moderate quality. TTM was found to be associated with a statistically significant improvement in mortality (mRS score 6) rates compared with the control group (RR = 0.61, 95% confidence interval [CI]: 0.40-0.94, p = 0.026). However, there was no statistically significant difference in unfavorable outcomes (mRS 4-6) between the TTM and control groups (RR = 0.94, 95% CI: 0.71-1.26, p = 0.702). The incidence of adverse events, including DCI, CVS, pneumonia, cardiac complications, and electrolyte imbalance, did not significantly differ between the two groups. In conclusion, our overall results suggest that TTM does not significantly reduce unfavorable outcomes in poor-grade aSAH patients. However, TTM may decrease mortality rates. Preoperative TTM may cause patients to miss the opportunity for surgery, although it temporarily protects the brain. Furthermore, the incidence of adverse events was similar between the TTM and control groups.

6.
Angew Chem Int Ed Engl ; 63(33): e202407315, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38818545

RESUMO

Li metal is regarded as the "Holy Grail" in the next generation of anode materials due to its high theoretical capacity and low redox potential. However, sluggish Li ions interfacial transport kinetics and uncontrollable Li dendrites growth limit practical application of the energy storage system in high-power device. Herein, separators are modified by the addition of a coating, which spontaneously grafts onto the Li anode interface for in situ lithiation. The resultant alloy possessing of strong electron-donating property promotes the decomposition of lithium bistrifluoromethane sulfonimide in the electrolyte to form a LiF-rich alloy-doped solid electrolyte interface (SEI) layer. High ionic alloy solid solution diffusivity and electric field dispersion modulation accelerate Li ions transport and uniform stripping/plating, resulting in a high-power dendrite-free Li metal anode interface. Surprisingly, the formulated SEI layer achieves an ultra-long cycle life of over 8000 h (20,000 cycles) for symmetric cells at a current density of 10 mA cm-2. It also ensures that the NCM(811)//PP@Au//Li full cell at ultra-high currents (40 C) completes the charging/discharging process in only 68 s to provide high capacity of 151 mAh g-1. The results confirm that this scalable strategy has great development potential in realizing high power dendrite-free Li metal anode.

8.
Water Res ; 255: 121477, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38520778

RESUMO

Iodinated X-ray contrast media (ICM) are ubiquitously present in water sources and challenging to eliminate using conventional processes, posing a significant risk to aquatic ecosystems. Ultraviolet light-emitting diodes (UV-LED) emerge as a promising technology for transforming micropollutants in water, boasting advantages such as diverse wavelengths, elimination of chemical additives, and no induction of microorganisms' resistance to disinfectants. The research reveals that iohexol (IOX) degradation escalates as UV wavelength decreases, attributed to enhanced photon utilization efficiency. Pseudo-first-order rate constants (kobs) were determined as 3.70, 2.60, 1.31 and 0.65 cm2 J-1 at UV-LED wavelengths of 255, 265, 275 and 285 nm, respectively. The optical properties of dissolved organic matter (DOM) and anions undeniably influence the UV-LED photolysis process through photon competition and the generation of reactive substances. The influence of Cl- on IOX degradation was insignificant at UV-LED 255, but it promoted IOX degradation at 265, 275 and 285 nm. IOX degradation was accelerated by ClO2-, NO3-and HA due to the formation of various reactive species. In the presence of NO3-, the kobs of IOX followed the order: 265 > 255 > 275 > 285 nm. Photosensitizers altered the spectral dependence of IOX, and the intermediate photoactivity products were detected using electron spin resonance. The transformation pathways of IOX were determined through density functional theory calculations and experiments. Disinfection by-products (DBPs) yields of IOX during UV-LED irradiation decreased as the wavelength increased: 255 > 265 > 275 > 285 nm. The cytotoxicity index value decreased as the UV-LED wavelength increased from 255 to 285 nm. These findings are crucial for selecting the most efficient wavelength for UV-LED degradation of ICM and will benefit future water purification design.

9.
Small ; 20(33): e2400962, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38511578

RESUMO

Bioelectrochemical reactions using whole-cell biocatalysts are promising carbon-neutral approaches because of their easy operation, low cost, and sustainability. Bidirectional (outward or inward) electron transfer via exoelectrogens plays the main role in driving bioelectrochemical reactions. However, the low electron transfer efficiency seriously inhibits bioelectrochemical reaction kinetics. Here, a three dimensional and artificial nanoparticles-constituent inverse opal-indium tin oxide (IO-ITO) electrode is fabricated and employed to connect with exoelectrogens (Shewanella loihica PV-4). The above electrode collected 128-fold higher cell density and exhibited a maximum current output approaching 1.5 mA cm-2 within 24 h at anode mode. By changing the IO-ITO electrode to cathode mode, the exoelectrogens exhibited the attractive ability of extracellular electron uptake to reduce fumarate and 16 times higher reverse current than the commercial carbon electrode. Notably, Fe-containing oxide nanoparticles are biologically synthesized at both sides of the outer cell membrane and probably contributed to direct electron transfer with the transmembrane c-type cytochromes. Owing to the efficient electron exchange via artificial and biosynthetic nanoparticles, bioelectrochemical CO2 reduction is also realized at the cathode. This work not only explored the possibility of augmenting bidirectional electron transfer but also provided a new strategy to boost bioelectrochemical reactions by introducing biohybrid nanoparticles.


Assuntos
Eletrodos , Nanopartículas , Shewanella , Transporte de Elétrons , Shewanella/metabolismo , Nanopartículas/química , Compostos de Estanho/química , Técnicas Eletroquímicas/métodos , Eletroquímica , Dióxido de Carbono/metabolismo , Dióxido de Carbono/química , Fontes de Energia Bioelétrica
10.
Plant Cell ; 36(6): 2375-2392, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38470570

RESUMO

Homeodomain (HD) proteins regulate embryogenesis in animals such as the fruit fly (Drosophila melanogaster), often in a concentration-dependent manner. HD-leucine zipper (Zip) IV family genes are unique to plants and often function in the L1 epidermal cell layer. However, our understanding of the roles of HD-Zip IV family genes in plant morphogenesis is limited. In this study, we investigated the morphogenesis of tomato (Solanum lycopersicum) multicellular trichomes, a type of micro-organ in plants. We found that a gradient of the HD-Zip IV regulator Woolly (Wo) coordinates spatially polarized cell division and cell expansion in multicellular trichomes. Moreover, we identified a TEOSINTE BRANCHED1, CYCLOIDEA, and PROLIFERATING CELL NUCLEAR ANTIGEN BINDING FACTOR (TCP) transcription factor-encoding gene, SlBRANCHED2a (SlBRC2a), as a key downstream target of Wo that regulates the transition from cell division to cell expansion. High levels of Wo promote cell division in apical trichome cells, whereas in basal trichome cells, Wo mediates a negative feedback loop with SlBRC2a that forces basal cells to enter endoreduplication. The restricted high and low activities of Wo pattern the morphogenesis of tomato multicellular trichomes. These findings provide insights into the functions of HD-Zip IV genes during plant morphogenesis.


Assuntos
Regulação da Expressão Gênica de Plantas , Morfogênese , Proteínas de Plantas , Solanum lycopersicum , Tricomas , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Solanum lycopersicum/citologia , Tricomas/crescimento & desenvolvimento , Tricomas/genética , Tricomas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Morfogênese/genética , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Divisão Celular
11.
Huan Jing Ke Xue ; 45(3): 1349-1360, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471851

RESUMO

Pollution variation, source characteristics, and meteorological effects of water-soluble inorganic ions (WSIIs) in PM2.5 were analyzed in Xinxiang city, Henan Province. PM2.5 samples and their chemical components were monitored online by using URG-9000 in four seasons:winter (January, 2022), spring (April, 2022), summer (July, 2022), and fall (October, 2022). The results showed that the TWSIIs had the same seasonal fluctuations as PM2.5. The average seasonal concentrations of WSIIs ranged from 19.62-72.15 µg·m-3, accounting for more than 60% of PM2.5, demonstrating that WSIIs were the major components of PM2.5. The annual concentration value of NO3-/SO42- was 2.11, which showed an increasing trend, suggesting predominantly mobile sources for secondary inorganic aerosols (SNA). Further, the molar concentration value [NH4+]/[NO3-] was 1.95, demonstrating that agriculture emissions were the dominant contributors to atmospheric nitrogen. Furthermore, the backward trajectory analysis showed that the concentrations of Ca2+ and Mg2+ were higher when the northeasterly wind prevailed and the wind speed was high. High values of SOR and NOR were correlated with low temperatures and high relative humidity (T < 8℃, RH > 60%), demonstrating that more gaseous precursors were converted into sulfate and nitrate. At high temperatures (T > 24℃), there was no apparent high NOR value like that for SOR, mainly due to the decomposition of NH4NO3 at high temperatures. Finally, backward trajectories associated with the PMF-resolved results were used to explore the regional transport characteristics. The results illustrated that dust sources in the study areas were mainly influenced by air trajectories originating from the northwest regions, whereas secondary sulfate, secondary nitrate, and biomass sources contributed more to WSIIs when wind speed and altitude air masses were low in the area surrounding the observation site.

12.
Mar Environ Res ; 196: 106444, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484649

RESUMO

To study the environmental responses of tropical cyclones (TCs) in continental shelf regions, TCs passing over the Yellow Sea and Bohai Sea (YBS) during 2002-2020 were investigated, with a special focus on how competition between ocean thermal structure and TC characteristics modulates ocean surface changes. The spatial distributions of the climatic mixed layer depth (MLD), accumulated wind forcing power index (WPi), accumulated sea surface temperature (SST) changes and accumulated chlorophyll (Chl-a) changes in the YBS were calculated. The linear regressions indicate that both the TC-induced SST cooling and TC-induced Chl-a increase are correlated with the TC wind speed rather than the translation speed, especially when the TC forcing depth (Zmixing) is greater than the MLD. Otherwise, both the changes in SST and Chl-a are correlated with the TC translation speed when Zmixing is shallower than the MLD. Further study has shown that whether TCs can break the MLD is also a key condition for oceanic responses. In the southern YBS, which has a deep-sea basin and MLD, the TC wind speed is the major factor affecting SST cooling and Chl-a increase, as TCs need more strength to reach the MLD. However, in the northern YBS, which has the shallowest sea basin and MLD, even weak TCs can easily break the MLD and reach the seabed; thus, ocean surface changes are associated mainly with the TC translation speed. The composite results reveal that both the maximum SST cooling center (1.64 °C) and the maximum Chl-a increasing center (0.14 log10(mg/m3)) are located on the right and behind the TC center, respectively. In addition, TC-induced SST cooling and Chl-a increase were initiated two days prior to TC passage and then reached their maximum values after 1 day. It takes approximately 7-8 days for the Chl-a concentration to recover, but it takes a much longer time (>15 days) for the SST to recover.


Assuntos
Tempestades Ciclônicas , Temperatura , Oceanos e Mares , Clorofila , Modelos Lineares
13.
Elife ; 122024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345841

RESUMO

CLC-2 is a voltage-gated chloride channel that contributes to electrical excitability and ion homeostasis in many different tissues. Among the nine mammalian CLC homologs, CLC-2 is uniquely activated by hyperpolarization, rather than depolarization, of the plasma membrane. The molecular basis for the divergence in polarity of voltage gating among closely related homologs has been a long-standing mystery, in part because few CLC channel structures are available. Here, we report cryoEM structures of human CLC-2 at 2.46 - 2.76 Å, in the presence and absence of the selective inhibitor AK-42. AK-42 binds within the extracellular entryway of the Cl--permeation pathway, occupying a pocket previously proposed through computational docking studies. In the apo structure, we observed two distinct conformations involving rotation of one of the cytoplasmic C-terminal domains (CTDs). In the absence of CTD rotation, an intracellular N-terminal 15-residue hairpin peptide nestles against the TM domain to physically occlude the Cl--permeation pathway. This peptide is highly conserved among species variants of CLC-2 but is not present in other CLC homologs. Previous studies suggested that the N-terminal domain of CLC-2 influences channel properties via a "ball-and-chain" gating mechanism, but conflicting data cast doubt on such a mechanism, and thus the structure of the N-terminal domain and its interaction with the channel has been uncertain. Through electrophysiological studies of an N-terminal deletion mutant lacking the 15-residue hairpin peptide, we support a model in which the N-terminal hairpin of CLC-2 stabilizes a closed state of the channel by blocking the cytoplasmic Cl--permeation pathway.


Assuntos
Canais de Cloro CLC-2 , Animais , Humanos , Fenômenos Biofísicos , Canais de Cloro CLC-2/química , Eletrofisiologia , Mamíferos/metabolismo , Peptídeos/metabolismo , Microscopia Crioeletrônica
14.
World Neurosurg ; 183: e846-e859, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38237800

RESUMO

OBJECTIVE: We assessed the effectiveness and safety of target temperature management (TTM) in treating patients with poor-grade aneurysmal subarachnoid hemorrhage (aSAH). The primary objective was to evaluate the neurological outcome at 3 months. Secondary objectives were to assess mortality, delayed cerebral ischemia, cerebral edema, hydrocephalus, midline shift, and laboratory indicators related to TTM. METHODS: A single-blind, nonrandomized controlled trial was conducted. After admission, patients with poor-grade aSAH (Hunt-Hess scores IV âˆ¼ V) were assigned to a TTM group or a control group in a 1:1 ratio. TTM with core temperatures ranging from 36°C to 37°C was performed immediately and maintained until microclipping or endovascular embolization. Subsequently, rapid induction to 33°C ∼ 35°C was carried out and maintained for 3 to 5 days. Then, the patients underwent slow rewarming to 36°C ∼ 37°C and maintained at that temperature for a minimum of 48 hours. RESULTS: Sixty patients (30 treated with TTM and 30 with standard treatment) were included in the study. At 3 months, a favorable prognosis (modified Rankin scale score 0 to 3) was significantly higher in the TTM group than in the control group (n = 14, 46.7% vs. n = 6, 20.0%, P = 0.028). Adjusted multivariate logistics regression analysis indicated that TTM (odds ratio = 0.20, 95% confidence interval: 0.05-0.77, P = 0.019) reduced the number of unfavorable prognoses 3 months after admission. CONCLUSIONS: This study demonstrated the effectiveness and safety of TTM in patients with poor-grade aSAH, and its implementation improved neurological outcomes. Multicenter randomized controlled studies with a large number of patients are needed to confirm these observations.


Assuntos
Hipotermia Induzida , Hemorragia Subaracnóidea , Humanos , Projetos Piloto , Estudos Retrospectivos , Método Simples-Cego , Hemorragia Subaracnóidea/complicações , Resultado do Tratamento
15.
Environ Technol ; 45(11): 2132-2143, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36601874

RESUMO

The efficient removal of 2-Methylisoborneol (2-MIB), a typical odour component, in water treatment plants (WTPs), poses a great challenge to conventional water treatment technology due to its chemical stability. In this study, the combination of ultraviolet light-emitting diode (UV-LED) and chlorine (UV-LED/chlorine) was exploited for 2-MIB removal, and the role of ultraviolet (UV) wavelength was investigated systematically. The results showed that UV or chlorination alone did not degrade 2-MIB effectively, and the UV/chlorine process could degrade 2-MIB efficiently, following the pseudo-first-order kinetic model. The 275 nm UV exhibited higher 2-MIB degradation efficiency in this UV-LED/chlorine system than 254 nm UV, 265 nm UV and 285 nm UV due to the highest mole adsorption coefficient and quantum yield of chlorine in 275 nm UV. ·OH and ·Cl produced in the 275 nm UV/chlorine system played major roles in 2-MIB degradation. HCO3- and Natural organic matter (NOM), prevalent in water, consumed ·OH and ·Cl, thus inhibiting the 2-MIB degradation by UV-LED/chlorine. In addition, NOM and 2-MIB could form a photonic competition effect. The degradation of 2-MIB by UV-LED/chlorine was done mainly through dehydration and demethylation, and odorous intermediates, such as camphor, were produced. 2-MIB was degraded through the α bond fracture and six-membered ring opening to form saturated or unsaturated hydrocarbons and aldehydes. Four DBPs, chloroform (CF), trichloroacetaldehyde (TCE), trichloroacetone (TCP) and dichloroacetone (DCP), were mainly generated, and CF was the most significant by-product.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Cloro/química , Desinfecção/métodos , Poluentes Químicos da Água/química , Raios Ultravioleta , Halogenação , Clorofórmio , Cinética , Purificação da Água/métodos , Oxirredução
16.
Small ; 20(3): e2306806, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37688339

RESUMO

The issues of polysulfide shuttling and lethargic sulfur redox reaction (SROR) kinetics are the toughest obstacles of lithium-sulfur (Li-S) battery. Herein, integrating the merits of increased density of metal sites and synergistic catalytic effect, a unique single-atom catalyst (SAC) with nonmetallic-bonding Fe-Mn diatomic pairs anchored on hollow nitrogen-doped carbonaceous nanodisk (denoted as FeMnDA@NC) is successfully constructed and well characterized by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy, X-ray absorption spectroscopy, etc. Density functional theory calculation indicates that the Fe-Mn diatomic pairs can effectively inhibit the shuttle effect by enhancing the adsorption ability retarding the polysulfide migration and accelerate the SROR kinetics. As a result, the Li-S battery assembled with FeMnDA@NC modified separator possesses an excellent electrochemical performance with ultrahigh specific capacities of 1419 mAh g-1 at 0.1 C and 885 mAh g-1 at 3.0 C, respectively. An outstanding specific capacity of 1165 mAh g-1 is achieved at 1.0 C and maintains at 731 mAh g-1 after 700 cycles. Notably, the assembled Li-S battery with a high sulfur loading of 5.35 mg cm-2 harvests a practical areal capacity of 5.70 mAh cm-2 at 0.2 C. A new perspective is offered here to construct advanced SACs suitable for the Li-S battery.

17.
Environ Sci Pollut Res Int ; 31(2): 3090-3104, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38079045

RESUMO

Heavy metals (Ni, Cr, W, Cd, and Pb) and rare earth elements (REE) were investigated in the flood plain sediments of an island of the lower Yangtze River near Nanjing to determine how the vertical distribution of heavy metals could be affected by natural sedimentation processes and anthropogenic contamination. Stratigraphic analyses of magnetic susceptibility and the mean grain size distribution of the deposits enabled us to identify layers associated with a relatively high influx of suspended sediments that resulted in sudden changes in the concentrations of heavy metals. The results show that layers associated with high sediment influx (0.8 m depth) displayed low concentrations of Cr, Ni, W, and Cd that were mainly lithogenic in origin. The Post Archean Australian Shale (PAAS) normalized REE patterns in the flood plain cores were enrichment in Ce and Eu relative to PAAS, indicating that the sediments were most likely derived from a mixture of sediments and not from an anthropogenic source. Sharp increases in Y/Ho ratios, as well as heavy metal (Cd, Cr, Ni, and W) and Y concentrations were observed in the uppermost layer that could have been deposited from the rapid transport of sediment-laden, contaminated waters. The temporal (vertical) trends in Pb concentrations may be strongly influenced by coal burning. Elevated Pb concentrations (350 ppm and 1000 ppm) correlate with high magnetic susceptibility (> 200 m3 × kg-1) and the history of thermal power plant (1910-2002) activity. The anthropogenic inputs of Pb were, however, not diluted by high suspended sediment loads, which supports the argument that Pb was derived from fly ash.


Assuntos
Metais Pesados , Metais Terras Raras , Poluentes Químicos da Água , Cádmio/análise , Chumbo/análise , Sedimentos Geológicos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Austrália , Metais Pesados/análise , Metais Terras Raras/análise , Rios , China , Medição de Risco
18.
Sci Total Environ ; 912: 168920, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38029977

RESUMO

Pre-oxidation and powdered activate carbon (PAC) are usually used to remove algae and odorants in drinking waterworks. However, the influence of interaction between oxidants and PAC on the treatment performance are scarcely known. This study systematically investigated the combination schemes of four oxidants (KMnO4, NaClO, ClO2, and O3) and PAC on the inactivation of Microcystis aeruginosa cells and removal of four frequently detected odorants in raw water (diethyl disulfide (DEDS), 2,2'-oxybis(1chloropropane) (DCIP), 2-methylisoborneol (2-MIB) and geosmin (GSM)). O3 showed highest pseudo-first-order removal rate for all four compounds and NaClO exhibited highest inactivation rates for the cell viability and Chlorophyll a (Chl-a). The Freundlich model fitted well for the adsorption of DEDS and DCIP by PAC. When treated by combined oxidation/PAC, the removal ratio of algae cells and odorants were lower (at least 1.6 times) than the sum of removal ratios obtained in oxidation or PAC adsorption alone. Among these four oxidants, the highest synchronous control efficiency of odorants (52 %) and algae (66 %) was achieved by NaClO/PAC. Prolonging the dosage time interval promoted the removal rates. The pre-PAC/post-oxidation processes possessed comparable efficiency for the removal of odorants and algae cells comparing with pre-oxidation/post-PAC process, but significantly inhibited formation of disinfection byproducts (DBPs), especially for the formation of C-DBPs (for NaClO and ClO2), bromate (for O3) and chlorate/chlorite (for ClO2). This study could provide a better understanding of improving in-situ operation of the combined pre-treatments of oxidation and PAC for source water.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Oxidantes , Desinfecção , Carvão Vegetal , Odorantes , Adsorção , Pós , Clorofila A , Água
19.
ACS Omega ; 8(50): 47646-47657, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38144085

RESUMO

During the extraction and processing of coal, a large amount of solid waste, collectively known as gangue, is produced. This gangue has a low carbon content but a high ash content, accounting for approximately 15 to 20% of the total coal yield. Before coal is used, coal and gangue must be effectively separated to reduce the gangue content in the raw coal and improve the efficiency of coal utilization. This study introduces a classification method for coal and gangue based on a combination of laser-induced breakdown spectroscopy (LIBS) and deep learning. The method employs Gramian angular summation fields (GASF) to convert 1D spectral data into 2D time-series data, visualizing them as 2D images, before employing a novel deep learning model-GASF-CNN-for coal and gangue classification. GASF-CNN enhances model focus on critical features by introducing the SimAM attention mechanism, and additionally, the fusion of various levels of spectral features is achieved through the introduction of residual connectivity. GASF-CNN was trained and tested using a spectral data set containing coal and gangue. Comparative experimental results demonstrate that GASF-CNN outperforms other machine learning and deep learning models across four evaluation metrics. Specifically, it achieves 98.33, 97.06, 100, and 98.51% in the accuracy, recall, precision, and F1 score metrics, respectively, thereby achieving an accurate classification of coal and gangue.

20.
Proc Natl Acad Sci U S A ; 120(38): e2310163120, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37703282

RESUMO

Callus is a reprogrammed cell mass involved in plant regeneration and gene transformation in crop engineering. Pluripotent callus cells develop into fertile shoots through shoot regeneration. The molecular basis of the shoot regeneration process in crop callus remains largely elusive. This study pioneers the exploration of the spatial transcriptome of tomato callus during shoot regeneration. The findings reveal the presence of highly heterogeneous cell populations within the callus, including epidermis, vascular tissue, shoot primordia, inner callus, and outgrowth shoots. By characterizing the spatially resolved molecular features of shoot primordia and surrounding cells, specific factors essential for shoot primordia formation are identified. Notably, chlorenchyma cells, enriched in photosynthesis-related processes, play a crucial role in promoting shoot primordia formation and subsequent shoot regeneration. Light is shown to promote shoot regeneration by inducing chlorenchyma cell development and coordinating sugar signaling. These findings significantly advance our understanding of the cellular and molecular aspects of shoot regeneration in tomato callus and demonstrate the immense potential of spatial transcriptomics in plant biology.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Transcriptoma , Células Epiteliais , Perfilação da Expressão Gênica , Regeneração/genética
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