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1.
Plant Physiol Biochem ; 211: 108726, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38744083

RESUMEN

Tea is one of the most prevalent non-alcoholic beverages. The leaves of tea plants hyperaccumulate anthocyanins under cold stress, resulting in enhanced bitterness. Previously, we determined that the RING-type E3 ubiquitin ligase CsMIEL1 from the tea plant (Camellia sinensis (L.) O. Kuntze) is involved in the response to stress conditions. This study aimed to determine the role of CsMIEL1 in anthocyanin accumulation at the post-translational modification level. The results showed that the heterologous expression of CsMIEL1 led to an 86% decrease in anthocyanin levels, resulting in a significant decrease in the mRNA levels of related genes in Arabidopsis at low temperatures but no significant differences in other phenotypes. Furthermore, multi-omics analysis and yeast two-hybrid library screening were performed to identify potential downstream targets of CsMIEL1. The results showed that the overexpression of CsMIEL1 resulted in 45% (448) of proteins being differentially expressed, of which 8% (36) were downregulated in A.thaliana, and most of these differentially expressed proteins (DEPs) were clustered in the plant growth and secondary metabolic pathways. Among the 71 potential targets that may interact with CsMIEL1, CsMYB90 and CsGSTa, which are related to anthocyanin accumulation, were selected. In subsequent analyses, these two proteins were verified to interact with CsMIEL1 via yeast two-hybrid (Y2H) and pull-down analyses in vitro. In summary, we explored the potential mechanism by which the E3 ligase relieves anthocyanin hyperaccumulation at low temperatures in tea plants. These results provide a new perspective on the mechanisms of anthocyanin regulation and the molecular breeding of tea plants.

2.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(5): 556-561, 2024 May 15.
Artículo en Chino | MEDLINE | ID: mdl-38752241

RESUMEN

Objective: To compare the effect of sciatic nerve block (SNB) combined with continuted femoral nerve block (FNB) or continuted adductor canal block (ACB) on pain and motor function after total knee arthroplasty (TKA). Methods: A total of 60 patients with TKA-treated osteoarthritis of the knee who met the selection criteria were enrolled between November 2020 and February 2021 and randomised allocated into the study group (SNB combined with continuted ACB) and the control group (SNB combined with continuted FNB), with 30 cases in each group. There was no significant difference in gender, age, body mass, height, body mass index, preoperative Hospital for Special Surgery (HSS) score, femoral tibial angle, and medial proximal tibial angle between the two groups ( P>0.05). The operation time, the initial time to the ground, the initial walking distance, and the postoperative hospital stay were recorded. At 2, 4, 6, 12, 24, and 48 hours after operation, the numerical rating scale (NRS) score was used to evaluate the rest pain around the knee joint, the quadriceps femoris muscle strength was evaluated by the freehand muscle strength method, and the knee flexion and extension angles were measured. Results: There was no significant difference in the operation time and initial walking distance between the two groups ( P>0.05); the initial time to the ground and postoperative hospital stay of the study group were significantly shorter than those of the control group ( P<0.05). Except for the 48-hour postoperative NRS score of the study group, which was significantly lower than that of the control group ( P<0.05), there was no significant difference in the NRS scores between the two groups at the remaining time points ( P>0.05). The quadriceps femoris muscle strength from 4 to 24 hours postoperatively and the knee extension angle from 2 to 6 hours postoperatively of the study group were significantly better than those of the control group ( P<0.05); the differences in the quadriceps femoris muscle strength and knee extension and flexion angles between the two groups at the remaining time points were not significant ( P>0.05). Conclusion: SNB combined with either continuted ACB or continuted FNB can effectively relieve pain in patients after TKA, and compared with combined continuted FNB, combined continuted ACB has less effect on quadriceps femoris muscle strength, and patients have better recovery of knee flexion and extension mobility.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Nervio Femoral , Bloqueo Nervioso , Dolor Postoperatorio , Nervio Ciático , Humanos , Artroplastia de Reemplazo de Rodilla/métodos , Bloqueo Nervioso/métodos , Dolor Postoperatorio/etiología , Dolor Postoperatorio/prevención & control , Osteoartritis de la Rodilla/cirugía , Femenino , Masculino , Dimensión del Dolor , Tempo Operativo , Anciano , Tiempo de Internación
3.
Plant Commun ; : 100942, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38720463

RESUMEN

Feralization is an important evolutionary process, but the mechanisms behind it remain poorly understood. Here, we use the ancient fiber crop, ramie (Boehmeria nivea (L.) Gaudich.) as a model to investigate genomic changes associated with both domestication and fertilization. We first produced a chromosome-scale de novo genome assembly of feral ramie and investigated structural variations between feral and domesticated ramie genomes. Next, 915 accessions from 20 countries were gathered, comprising cultivars, major landraces, feral populations and wild progenitor. Based on whole genome resequencing of these accessions, the most comprehensive ramie genomic variation map to date was constructed. Phylogenetic, demographic, and admixture signal detection analyses indicate that feral ramie is of exoferal or exo-endo origin, i.e., descended from hybridization between domesticated ramie and wild progenitor or ancient landraces. Feral ramie has greater genetic diversity than wild or domesticated ramie, and genomic regions affected by natural selection during feralization are different from those under selection during domestication. Ecological analyses showed that feral and domesticated ramie have similar ecological niches which are substantially different from the niche of the wild progenitor, and three environmental variables were associated with habitat-specific adaptation in feral ramie. Our findings advance our understanding of feralization, providing a scientific basis for the excavation of new crop germplasm resources and offering novel insights into the evolution of feralization in nature.

4.
World J Gastrointest Surg ; 16(4): 1184-1188, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38690059

RESUMEN

BACKGROUND: Splenic rupture associated with Behçet's syndrome (BS) is extremely rare, and there is no consensus on its management. In this case report, a patient with BS-associated splenic rupture was successfully treated with splenic artery embolization (SAE) and had a good prognosis after the intervention. CASE SUMMARY: The patient was admitted for pain in the left upper abdominal quadrant. He was diagnosed with splenic rupture. Multiple oral and genital aphthous ulcers were observed, and acne scars were found on his back. He had a 2-year history of BS diagnosis, with symptoms of oral and genital ulcers. At that time, he was treated with oral corticosteroids for 1 month, but the symptoms did not alleviate. He underwent SAE to treat the rupture. On the first day after SAE, the patient reported a complete resolution of abdominal pain and was discharged 5 d later. Three months after the intervention, a computed tomography examination showed that the splenic hematoma had formed a stable cystic effusion, suggesting a good prognosis. CONCLUSION: SAE might be a good choice for BS-associated splenic rupture based on good surgical practice and material selection.

5.
J Med Chem ; 67(9): 7504-7515, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38640354

RESUMEN

Food allergy (FA) poses a growing global food safety concern, yet no effective cure exists in clinics. Previously, we discovered a potent antifood allergy compound, butyrolactone I (BTL-I, 1), from the deep sea. Unfortunately, it has a very low exposure and poor pharmacokinetic (PK) profile in rats. Therefore, a series of structural optimizations toward the metabolic pathways of BTL-I were conducted to provide 18 derives (2-19). Among them, BTL-MK (19) showed superior antiallergic activity and favorable pharmacokinetics compared to BTL-I, being twice as potent with a clearance (CL) rate of only 0.5% that of BTL-I. By oral administration, Cmax and area under the concentration-time curve (AUC0-∞) were 565 and 204 times higher than those of BTL-I, respectively. These findings suggest that butyrolactone methyl ketone (BTL-BK) could serve as a drug candidate for the treatment of FAs and offer valuable insights into optimizing the druggability of lead compounds.


Asunto(s)
4-Butirolactona , Antialérgicos , Animales , 4-Butirolactona/análogos & derivados , 4-Butirolactona/farmacología , 4-Butirolactona/química , 4-Butirolactona/farmacocinética , 4-Butirolactona/administración & dosificación , Administración Oral , Ratas , Humanos , Antialérgicos/farmacocinética , Antialérgicos/farmacología , Antialérgicos/química , Antialérgicos/administración & dosificación , Relación Estructura-Actividad , Masculino , Ratas Sprague-Dawley , Disponibilidad Biológica , Hipersensibilidad a los Alimentos/tratamiento farmacológico , Ratones
6.
Molecules ; 29(6)2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38543028

RESUMEN

The burgeoning demand for miniaturized energy storage devices compatible with the miniaturization trend of electronic technologies necessitates advancements in micro-supercapacitors (MSCs) that promise safety, cost efficiency, and high-speed charging capabilities. However, conventional aqueous MSCs face a significant limitation due to their inherently narrow electrochemical potential window, which restricts their operational voltage and energy density compared to their organic and ionic liquid counterparts. In this study, we introduce an innovative aqueous NaCl/H2O/EG hybrid gel electrolyte (comprising common salt (NaCl), H2O, ethylene glycol (EG), and SiO2) for Ti3C2Tx MXene MSCs that substantially widens the voltage window to 1.6 V, a notable improvement over traditional aqueous system. By integrating the hybrid electrolyte with 3D-printed MXene electrodes, we realized MSCs with remarkable areal capacitance (1.51 F cm-2) and energy density (675 µWh cm-2), significantly surpassing existing benchmarks for aqueous MSCs. The strategic formulation of the hybrid electrolyte-a low-concentration NaCl solution with EG-ensures both economic and environmental viability while enabling enhanced electrochemical performance. Furthermore, the MSCs fabricated via 3D printing technology exhibit exceptional flexibility and are suitable for modular device integration, offering a promising avenue for the development of high-performance, sustainable energy storage devices. This advancement not only provides a tangible solution to the challenge of limited voltage windows in aqueous MXene MSCs but also sets a new precedent for the design of next-generation MSCs that align with the needs of an increasingly microdevice-centric world.

7.
J Ethnopharmacol ; 328: 118116, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38548118

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Aristolochic acids (AAs) are naturally occurring nitro phenanthrene carboxylic acids primarily found in plants of the Aristolochiaceae family. Aristolochic acid D (AAD) is a major constituent in the roots and rhizomes of the Chinese herb Xixin (the roots and rhizomes of Asarum heterotropoides F. Schmidt), which is a key material for preparing a suite of marketed Chinese medicines. Structurally, AAD is nearly identical to the nephrotoxic aristolochic acid I (AAI), with an additional phenolic group at the C-6 site. Although the nephrotoxicity and metabolic pathways of AAI have been well-investigated, the metabolic pathway(s) of AAD in humans and the influence of AAD metabolism on its nephrotoxicity has not been investigated yet. AIM OF THE STUDY: To identify the major metabolites of AAD in human tissues and to characterize AAD O-glucuronidation kinetics in different enzyme sources, as well as to explore the influence of AAD O-glucuronidation on its nephrotoxicity. MATERIALS AND METHODS: The O-glucuronide of AAD was biosynthesized and its chemical structure was fully characterized by both 1H-NMR and 13C-NMR. Reaction phenotyping assays, chemical inhibition assays, and enzyme kinetics analyses were conducted to assess the crucial enzymes involved in AAD O-glucuronidation in humans. Docking simulations were performed to mimic the catalytic conformations of AAD in human UDP-glucuronosyltransferases (UGTs), while the predicted binding energies and distances between the deprotonated C-6 phenolic group of AAD and the glucuronyl moiety of UDPGA in each tested human UGT isoenzyme were measured. The mitochondrial membrane potentials (MMP) and reactive oxygen species (ROS) levels in HK-2 cells treated with either AAI, or AAD, or AAD O-glucuronide were tested, to elucidate the impact of O-glucuronidation on the nephrotoxicity of AAD. RESULTS: AAD could be rapidly metabolized in human liver and intestinal microsomes (HLM and HIM, respectively) to form a mono-glucuronide, which was purified and fully characterized as AAD-6-O-ß-D-glucuronide (AADG) by NMR. UGT1A1 was the predominant enzyme responsible for AAD-6-O-glucuronidation, while UGT1A9 contributed to a lesser extent. AAD-6-O-glucuronidation in HLM, HIM, UGT1A1 and UGT1A9 followed Michaelis-Menten kinetics, with the Km values of 4.27 µM, 9.05 µM, 3.87 µM, and 7.00 µM, respectively. Docking simulations suggested that AAD was accessible to the catalytic cavity of UGT1A1 or UGT1A9 and formed catalytic conformations. Further investigations showed that both AAI and AAD could trigger the elevated intracellular ROS levels and induce mitochondrial dysfunction and in HK-2 cells, but AADG was hardly to trigger ROS accumulation and mitochondrial dysfunction. CONCLUSION: Collectively, UGT1A-catalyzed AAD 6-O-glucuronidation represents a crucial detoxification pathway of this naturally occurring AAI analogs in humans, which is very different from that of AAI.


Asunto(s)
Ácidos Aristolóquicos , Enfermedades Mitocondriales , Humanos , Ácidos Aristolóquicos/toxicidad , Glucurónidos/metabolismo , Microsomas Hepáticos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Glucuronosiltransferasa/metabolismo , Cinética , Catálisis , Uridina Difosfato/metabolismo
8.
World J Gastrointest Oncol ; 16(2): 300-313, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38425402

RESUMEN

MicroRNAs (miRNAs) have received much attention in the past decade as potential key epigenomic regulators of tumors and cancer stem cells (CSCs). The abnormal expression of miRNAs is responsible for different phenotypes of gastric cancer stem cells (GCSCs). Some specific miRNAs could be used as promising biomarkers and therapeutic targets for the identification of GCSCs. This review summarizes the coding process and biological functions of miRNAs and demonstrates their role and efficacy in gastric cancer (GC) metastasis, drug resistance, and apoptosis, especially in the regulatory mechanism of GCSCs. It shows that the overexpression of onco-miRNAs and silencing of tumor-suppressor miRNAs can play a role in promoting or inhibiting tumor metastasis, apart from the initial formation of GC. It also discusses the epigenetic regulation and potential clinical applications of miRNAs as well as the role of CSCs in the pathogenesis of GC. We believe that this review may help in designing novel therapeutic approaches for GC.

9.
In Vitro Cell Dev Biol Anim ; 60(3): 287-299, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38485818

RESUMEN

The study aimed to investigate the effect of ginsenoside Rg1 on intervertebral disc degeneration (IVDD) in rats and IL-1ß-induced nucleus pulposus (NP) cells, and explore its underlying mechanism. Forty IVDD rat models were divided into the IVDD group, low-dose (L-Rg1) group (intraperitoneal injection of 20 mg/kg/d ginsenoside Rg1), medium-dose (M-Rg1) group (intraperitoneal injection of 40 mg/kg/d ginsenoside Rg1), and high-dose (H-Rg1) group (intraperitoneal injection of 80 mg/kg/d ginsenoside Rg1). The pathological change was observed by HE and safranin O-fast green staining. The expression of IL-1ß, IL-6, TNF-α, MMP3, aggrecan, and collagen II was detected. The expression of NF-κB p65 in IVD tissues was detected. Rat NP cells were induced by IL-1ß to simulate IVDD environment and divided into the control group, IL-1ß group, and 20, 50, and 100 µmol/L Rg1 groups. The cell proliferation activity, the apoptosis, and the expression of IL-6, TNF-α, MMP3, aggrecan, collagen II, and NF-κB pathway-related protein were detected. In IVDD rats, ginsenoside Rg1 improved the pathology of IVD tissues; suppressed the expression of IL-1ß, IL-6, TNF-α, aggrecan, and collagen II; and inhibited the expression of p-p65/p65 and nuclear translocation of p65, to alleviate the IVDD progression. In the IL-1ß-induced NP cells, ginsenoside Rg1 also improved the cell proliferation and inhibited the apoptosis and the expression of IL-6, TNF-α, aggrecan, collagen II, p-p65/p65, and IκK in a dose-dependent manner. Ginsenoside Rg1 alleviated IVDD in rats and inhibited apoptosis, inflammatory response, and ECM degradation in IL-1ß-induced NP cells. And Rg1 may exert its effect via inhibiting the activation of NF-κB signaling pathway.


Asunto(s)
Ginsenósidos , Degeneración del Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Animales , Ratas , Agrecanos/genética , Apoptosis , Colágeno/farmacología , Inflamación/patología , Interleucina-6/metabolismo , Disco Intervertebral/metabolismo , Disco Intervertebral/patología , Degeneración del Disco Intervertebral/tratamiento farmacológico , Degeneración del Disco Intervertebral/metabolismo , Degeneración del Disco Intervertebral/patología , Metaloproteinasa 3 de la Matriz/metabolismo , FN-kappa B/metabolismo , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo
10.
Int J Biol Macromol ; 267(Pt 1): 131150, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38556236

RESUMEN

Gut microbial ß-glucuronidases (gmß-GUS) played crucial roles in regulating a variety of endogenous substances and xenobiotics on the circulating level, thus had been recognized as key modulators of drug toxicity and human diseases. Inhibition or inactivation of gmß-GUS enzymes has become a promising therapeutic strategy to alleviate drug-induced intestinal toxicity. Herein, the Rhodiola crenulata extract (RCE) was found with potent and broad-spectrum inhibition on multiple gmß-GUS enzymes. Subsequently, the anti-gmß-GUS activities of the major constituents in RCE were tested and the results showed that 1,2,3,4,6-penta-O-galloyl-ß-d-glucopyranose (PGG) acted as a strong and broad-spectrum inhibitor on multiple gmß-GUS (including EcGUS, CpGUS, SaGUS, and EeGUS). Inhibition kinetic assays demonstrated that PGG effectively inhibited four gmß-GUS in a non-competitive manner, with the Ki values ranging from 0.12 µM to 1.29 µM. Docking simulations showed that PGG could tightly bound to the non-catalytic sites of various gmß-GUS, mainly via hydrogen bonding and aromatic interactions. It was also found that PGG could strongly inhibit the total gmß-GUS activity in mice feces, with the IC50 value of 1.24 µM. Collectively, our findings revealed that RCE and its constituent PGG could strongly inhibit multiple gmß-GUS enzymes, suggesting that RCE and PGG could be used for alleviating gmß-GUS associated enterotoxicity.


Asunto(s)
Inhibidores Enzimáticos , Microbioma Gastrointestinal , Simulación del Acoplamiento Molecular , Rhodiola , Rhodiola/química , Animales , Ratones , Microbioma Gastrointestinal/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Medicina Tradicional Tibetana , Cinética , Masculino
11.
Dalton Trans ; 53(15): 6583-6591, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38353272

RESUMEN

Recently, it has been reported that MXene is a promising pseudocapacitive material for energy storage, primarily due to its intercalation mechanism. However, Ti3C2Tx MXenes face challenges, such as inadequate layer spacing and low specific capacity, which greatly hinder their potential as anode materials for sodium storage. In this study, MXene was doped with sulfur to create a three-dimensional porous structure that resulted in an increased layer spacing. The sulfur-doped porous MXene (SPM) demonstrated exceptional performance as sodium ion battery anodes, with a capacity of 335.2 mA h g-1 after 490 cycles at 2 A g-1 and a long-term cycling performance of 256.1 mA h g-1 even after 2480 cycles at 5 A g-1. It is worth noting that the porous structure formed after sulfur-doping exhibits superior sodium storage performance compared to previously reported MXene-based electrodes. This highlights the feasibility of the structural construction strategy, offering an effective solution for energy storage and conversion applications.

12.
Chem Commun (Camb) ; 60(22): 3067-3070, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38386357

RESUMEN

MnO2-Mn3O4 heterostructure materials are applied in aqueous magnesium ion energy storage for the first time. The heterostructure yields an exceptionally high pseudocapacitance contribution, resulting in a specific capacitance of 313.5 F g-1 at 1 A g-1, which contrasts with that of MnO2 (108.8 F g-1) and Mn3O4 (123.5 F g-1). Additionally, it shows potential for practical applications as a cathode for magnesium ion hybrid supercapacitors (MHS).

13.
J Acoust Soc Am ; 155(2): 854-866, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38310609

RESUMEN

This paper proposes a high-performance receiver for underwater acoustic communications based on time reversal processing for multiple-input multiple-output (MIMO) systems. The receiver employs the vector approximate message passing (VAMP) algorithm as a soft equalizer in turbo equalization. By performing self-iteration between the inner soft slicer and the inner soft equalizer, the VAMP algorithm achieves near-optimal performance. Furthermore, an iterative channel-estimation-based soft successive interference cancellation method is incorporated to suppress co-channel interference in the MIMO system. Additionally, the introduction of passive time reversal technology can combine multiple channels into a single channel, which greatly reduces the computational complexity of the MIMO system, especially for large MIMO systems. The effectiveness of the proposed receiver is verified using experimental data collected in Songhua Lake, China in 2019. The results demonstrate that the proposed receiver significantly reduces the complexity of the traditional parallel-VAMP receiver without sacrificing performance and outperforms other receivers of the same type. Moreover, our experimental results also verify that the VAMP-turbo outperforms the generalized approximate message passing (GAMP)-turbo in terms of bit error rate and convergence performance.

14.
Clin Nutr ESPEN ; 59: 355-364, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38220397

RESUMEN

BACKGROUND: The geriatric nutritional risk index (GNRI) and prognostic nutritional index (PNI) are considered prognostic factors for several cancers. This study aimed to investigate the relationship between the GNRI and PNI for survival outcomes in patients with hepatocellular carcinoma (HCC). METHODS: We retrospectively analyzed 1666 patients with HCC who underwent hepatectomy. Restricted cubic spline regression was used to analyze the relationship between the GNRI and PNI for recurrence and mortality. Cox proportional hazards regression analysis was used to evaluate the risk factors associated with overall survival (OS) and recurrence-free survival (RFS). Interaction analysis was performed to investigate the comprehensive effects of the GNRI, PNI, and subgroup parameters on the prognosis of patients with HCC. RESULTS: The risks of death and recurrence decreased rapidly and gradually stabilized as the GNRI and PNI scores increased. Patients with lower GNRI and PNI scores had significantly shorter OS and RFS rates than those with higher scores. Multivariate analysis showed that high GNRI [HR and 95%CI = 0.77 (0.70-0.85), P < 0.001] and PNI [HR and 95%CI = 0.77 (0.70-0.86), P < 0.001] scores were associated with decreased mortality risk. This trend was maintained by confounding variables in adjusted models despite partial interactions with clinical factors. The combined GNRI and PNI analysis showed that HCC patients with high GNRI and PNI had longer OS and RFS. CONCLUSIONS: The GNRI and PNI showed good survival predictions in patients with HCC. Combining the GNRI with PNI may help predict the prognosis of patients (age>18 years) with HCC after hepatectomy.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Anciano , Adolescente , Carcinoma Hepatocelular/cirugía , Pronóstico , Evaluación Nutricional , Estudios Retrospectivos , Neoplasias Hepáticas/cirugía
15.
Waste Manag ; 176: 74-84, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38266477

RESUMEN

Aeration plays a crucial role in accelerating the secondary compression of municipal solid waste (MSW) for the scientific implementation of aerobic bioreactor technology. There are few comparative reports on the secondary compaction characteristics of MSW in aerobic and anaerobic bioreactors. In this study, six long-term compression tests were conducted to analyze the impact of aeration on MSW compression characteristics, considering two degradation conditions (i.e. aerobic and anaerobic conditions) and three overburden stresses (i.e. 30, 50 and 100 kPa). Model-fitting analysis was employed to examine the data from the tests and exiting literatures. The results showed that aeration effectively increased the rate of secondary compression, and slightly enhanced the steady-state secondary compression strain. In addition, these enhancements tended to decrease with increasing stresses. The increment ratio of the secondary compression rate constant (Rk) was concentrated in the range of 25 % to 100 %, and increases with the increase of aeration rate. The increment ratio of the steady-state secondary compression strain (Rε) ranged from 10 % to 90 %, for the MSW with higher content of paper and wood exhibited higher Rε. The advance ratio of the secondary compression stabilization time (Rt) fell within the range of 20-50 %, and Rt is higher when the moisture content is in the range of 50-65 %. These findings provide valuable guidance on the accelerated stabilization in aerobic bioreactors, providing practical references for the application of aerobic technology to informal landfills.


Asunto(s)
Eliminación de Residuos , Residuos Sólidos , Residuos Sólidos/análisis , Eliminación de Residuos/métodos , Anaerobiosis , Reactores Biológicos , Instalaciones de Eliminación de Residuos
16.
Natl Sci Rev ; 11(2): nwad305, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38213530

RESUMEN

The interaction between sites A, B and X with passivation molecules is restricted when the conventional passivation strategy is applied in perovskite (ABX3) photovoltaics. Fortunately, the revolving A-site presents an opportunity to strengthen this interaction by utilizing an external field. Herein, we propose a novel approach to achieving an ordered magnetic dipole moment, which is regulated by a magnetic field via the coupling effect between the chiral passivation molecule and the A-site (formamidine ion) in perovskites. This strategy can increase the molecular interaction energy by approximately four times and ensure a well-ordered molecular arrangement. The quality of the deposited perovskite film is significantly optimized with inhibited nonradiative recombination. It manages to reduce the open-circuit voltage loss of photovoltaic devices to 360 mV and increase the power conversion efficiency to 25.22%. This finding provides a new insight into the exploration of A-sites in perovskites and offers a novel route to improving the device performance of perovskite photovoltaics.

17.
Huan Jing Ke Xue ; 45(1): 181-193, 2024 Jan 08.
Artículo en Chino | MEDLINE | ID: mdl-38216470

RESUMEN

To explore the distribution characteristics, blooming risk mechanism and driving factors of phytoplankton community structure in Fuchunjiang Reservoir. The variation characteristics of phytoplankton, zooplankton and physicochemical indicators in Fuchunjiang Reservoir and its upper and lower reaches were investigated in 2020 and 2021. Based on the phytoplankton functional groups, non-metric multidimensional scale analysis, redundancy analysis and other statistical methods, the seasonal succession characteristics and driving factors of phytoplankton functional groups were analyzed. A total of 18 phytoplankton functional groups were identified, in of which 10 were predominant. The composition of phytoplankton functional groups in the Fuchunjiang Reservoir was significant different. Spatially, the upstream were dominated by group C and P while the represent species were Cyclotella and Aulacoseira,reflecting the mixed meso-eutrophic environments. However, group P was the main group in Fuchunjiang reservoir, and the dominance decreased gradually along the stream direction. Meanwhile, in the downstream, MP has an absolute advantage at Qiantang River estuary. It reflected the environmental characteristics of frequent disturbance and high turbidity of tide-sensing rivers. In addition, the predominant functional groups demonstrated strong seasonal variations. The dominant functional groups were diverse in summer and consisted of P+L0+J+M+S1+H1+MP. In addition to group P (Aulacoseira), which was dominant throughout the year, it also included several groups represented by cyanobacteria and chlorophyta, reflecting the environmental characteristics of changeable habitats and vigorous productivity. In autumn, the succession was dominated by H1 group represented by Dolichospermum and the representative function groups were P and H1, reflecting the hydrological background of reduced flow and static flow. In winter, the increase of Cyclotella led to the predominance of group C, which was dominated by P+C, reflecting the changing conditions of weakened water exchange and intensified eutrophication problems. In spring, the dominant functional groups were gradually enriched and were composed of C, D, P, and MP, which also reflected the changing environmental habitat characteristics which caused by increasing rainfall and air temperature. According to the results of the C-R-S growth strategy, the Fuchunjiang Reservoir has been in the R strategy for a long time, which was consistent with the habitat characteristics of Fuchunjiang Reservoir and its upper and lower reaches with high disturbance and low stress. In addition, C strategy and S strategy appeared in some reaches, reflecting the variability of water quality and hydrology. RDA analysis showed that water temperature, discharge, zooplankton biomass, permanganate index, total nitrogen and total phosphorus were significantly correlated with the seasonal succession of phytoplankton functional groups (P < 0.05), and temperature and flow pattern were probably the most critical factors for the succession. Studies have shown that the impact of hydrometeorological processes on phytoplankton in the Fuchunjiang Reservoir is crucial:high temperature and changing discharge during the summer may lead to cyanobacterial blooms in the Fuchunjiang reservoir; To reduce the risk of algal blooms, it is still necessary to increase the control of nitrogen and phosphorus load in rivers, and fully consider the coordination of water conservancy dispatch methods.


Asunto(s)
Cianobacterias , Diatomeas , Fitoplancton , Monitoreo del Ambiente , Estaciones del Año , Nitrógeno/análisis , Fósforo/análisis , Eutrofización , China
18.
Dalton Trans ; 53(4): 1640-1647, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38167672

RESUMEN

Manganese oxides are commonly employed as a cathode for magnesium ion storage in aqueous magnesium ion hybrid supercapacitors (MHS). However, sluggish reaction kinetics still hinders their practical application. Herein, we designed K-birnessite-MnO2 and electrostatically spun mulberry-like carbon composites (K-MnO2/HMCs) via an in situ growth technique. Benefiting from the 3D conductive carbon network substrate, the in situ fabricated K-MnO2 exhibits more active sites and provides more interfacial contact area between the electrode material and the electrolyte. This improvement enhances its conductivity, facilitating the rapid transfer of electrons, diffusion of ions, and redox reactions. As a result, K-MnO2/HMC-based MHS achieves a specific capacity of 168 mA h g-1 at 0.5 A g-1, simultaneously exhibiting a superior energy density of 111.1 W h kg-1 at a power density of 505 W kg-1. Furthermore, it demonstrates excellent high rate performance and a long cycling life for aqueous magnesium ion storage, offering new insights for MHS applications.

19.
Int J Biol Macromol ; 260(Pt 1): 129487, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38237821

RESUMEN

Guanine (G)-rich nucleic acid sequences can form diverse G-quadruplex structures located in functionally significant genome regions, exerting regulatory control over essential biological processes, including DNA replication in vivo. During the initiation of DNA replication, Cdc6 is recruited by the origin recognition complex (ORC) to target specific chromosomal DNA sequences. This study reveals that human Cdc6 interacts with G-quadruplex structure through a distinct region within the N-terminal intrinsically disordered region (IDR), encompassing residues 7-20. The binding region assumes a hook-type conformation, as elucidated by the NMR solution structure in complex with htel21T18. Significantly, mutagenesis and in vivo investigations confirm the highly specific nature of Cdc6's recognition of G-quadruplex. This research enhances our understanding of the fundamental mechanism governing the interaction between G-quadruplex and the N-terminal IDR region of Cdc6, shedding light on the intricate regulation of DNA replication processes.


Asunto(s)
ADN , G-Cuádruplex , Humanos , ADN/química , Replicación del ADN , Complejo de Reconocimiento del Origen/química , Complejo de Reconocimiento del Origen/genética , Complejo de Reconocimiento del Origen/metabolismo , Secuencia de Bases
20.
J Mol Med (Berl) ; 102(2): 231-245, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38051341

RESUMEN

Ischemic stroke is a devastative nervous system disease associated with high mortality and morbidity rates. Unfortunately, no clinically effective neuroprotective drugs are available now. In ischemic stroke, S100 calcium-binding protein b (S100b) binds to receptor for advanced glycation end products (Rage), leading to the neurological injury. Therefore, disruption of the interaction between S100B and Rage can rescue neuronal cells. Here, we designed a peptide, termed TAT-W61, derived from the V domain of Rage which can recognize S100b. Intriguingly, TAT-W61 can reduce the inflammatory caused by ischemic stroke through the direct binding to S100b. The further investigation demonstrated that TAT-W61 can improve pathological infarct volume and reduce the apoptotic rate. Particularly, TAT-W61 significantly improved the learning ability, memory, and motor dysfunction of the mouse in the ischemic stroke model. Our study provides a mechanistic insight into the abnormal expression of S100b and Rage in ischemic stroke and yields an invaluable candidate for the development of drugs in tackling ischemic stroke. KEY MESSAGES: S100b expression is higher in ischemic stroke, in association with a high expression of many genes, especially of Rage. S100b is directly bound to the V-domain of Rage. Blocking the binding of S100b to Rage improves the injury after ischemic stroke.


Asunto(s)
Accidente Cerebrovascular Isquémico , Ratones , Animales , Receptor para Productos Finales de Glicación Avanzada , Accidente Cerebrovascular Isquémico/patología , Neuronas , Péptidos/farmacología , Subunidad beta de la Proteína de Unión al Calcio S100/farmacología
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