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1.
Endoscopy ; 55(6): 557-562, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36758584

RESUMEN

BACKGROUND : There remain concerns regarding the technical feasibility of endoscopic resection for large gastrointestinal stromal tumors (GISTs), mainly relating to the risk of tumor rupture and the adequacy of the resection margins. This study aimed to evaluate the feasibility and therapeutic outcomes of the newly developed no-touch endoscopic full-thickness resection (NT-EFTR) technique for GISTs. METHODS : In this retrospective study, 92 patients with gastric GISTs undergoing NT-EFTR were included. Clinicopathological, endoscopic, and follow-up data were collected and analyzed. RESULTS : The median tumor size was 2.5 cm and en bloc resection was achieved in all patients with negative surgical margins. The median time of the NT-EFTR procedure was 59.5 minutes. Large tumors (> 3.0 cm), extraluminal tumor growth pattern, and large gastric defects were significant contributors to long operative times. Patients were discharged within 4 days postoperatively. During follow-up, all patients were free from local recurrence and distant metastasis. CONCLUSIONS : NT-EFTR was a feasible method for the resection of gastric GISTs and can be expected to achieve complete radical resection. Large tumors with extraluminal growth and large gastric defects impact procedural difficulty.


Asunto(s)
Resección Endoscópica de la Mucosa , Tumores del Estroma Gastrointestinal , Neoplasias Gástricas , Humanos , Tumores del Estroma Gastrointestinal/cirugía , Tumores del Estroma Gastrointestinal/patología , Estudios Retrospectivos , Resultado del Tratamiento , Neoplasias Gástricas/cirugía , Neoplasias Gástricas/patología , Resección Endoscópica de la Mucosa/métodos , Gastroscopía/métodos
2.
Sensors (Basel) ; 24(1)2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38202912

RESUMEN

As affected by limited information and the complex background, the accuracy of small-target water-floating garbage detection is low. To increase the detection accuracy, in this research, a small-target detection method based on APM-YOLOv7 (the improved YOLOv7 with ACanny PConv-ELAN and MGA attention) is proposed. Firstly, the adaptive algorithm ACanny (adaptive Canny) for river channel outline extraction is proposed to extract the river channel information from the complex background, mitigating interference of the complex background and more accurately extracting the features of small-target water-floating garbage. Secondly, the lightweight partial convolution (PConv) is introduced, and the partial convolution-efficient layer aggregation network module (PConv-ELAN) is designed in the YOLOv7 network to improve the feature extraction capability of the model from morphologically variable water-floating garbage. Finally, after analyzing the limitations of the YOLOv7 network in small-target detection, a multi-scale gated attention for adaptive weight allocation (MGA) is put forward, which highlights features of small-target garbage and decreases missed detection probability. The experimental results showed that compared with the benchmark YOLOv7, the detection accuracy in the form of the mean Average Precision (mAP) of APM-YOLOv7 was improved by 7.02%, that of mmAP (mAP0.5:0.95) was improved by 3.91%, and Recall was improved by 11.82%, all of which meet the requirements of high-precision and real-time water-floating garbage detection and provide reliable reference for the intelligent management of water-floating garbage.

3.
BMC Nurs ; 22(1): 218, 2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37357312

RESUMEN

BACKGROUND: Neonatal nurses' working environments are highly stressful, and burnout is common. This study examines the effect of socioeconomic factors, perceived stress, and social support on neonatal nurse burnout. METHODS: A total of 311 neonatal nurses participated in this study. They were administered a validated Maslach Burnout Inventory. The study employed a 14-item perceived stress scale (PSS-14) and a social support rate scale (SSRS) to examine stress, socioeconomic factors, and lifestyles. RESULTS: Of the neonatal nurses, 40.19% had burnout, 89.60% had mild burnout, and 10.40% had moderate burnout; no neonatal nurse experienced severe burnout. Young nurses and those with low technical skills, poor interpersonal relationships, irregular diet, and insufficient rest were exposed to burnout (all p < 0.05).Most burnout nurses experienced moderate-severe perceived stress, and their PSS-14 scores were higher (all p < 0.05).The scores for objective social support, subjective social support, utilization of social support, total SSRS scores, and the level of social support were all lower in burnout nurses (all p < 0.05). Perceived stress was correlated positively and significantly with emotional exhaustion and personal accomplishment (all p < 0.05). Social support correlated significantly with and reduced personal accomplishments (p < 0.05). Age, poor interpersonal relationships, perceived stress, and social support were all independent factors associated with neonatal nurse burnout (all p < 0.05). CONCLUSION: The prevalence of burnout in neonatal nurses was higher than average. Socioeconomic factors, higher perceived stress, and lower social support contribute to neonatal nurse burnout. Nursing managers should pay attention to socioeconomic factors, perceived stress, and social support among neonatal nurses and employ strategies to reduce neonatal nurse burnout.

4.
Sensors (Basel) ; 22(5)2022 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-35271198

RESUMEN

The dual-winding motor drive has recently been proposed in the field of fuel cell vehicles due to its performance and high robust advantages. Efforts for this new topology have been made by many researchers. However, the high-frequency resistance measurement of a proton exchange membrane fuel cell based on dual-winding motor drive architecture, which is important for water management to optimize the lifespan of fuel cells, was not employed in earlier works. In this paper, a new control method of the dual-winding motor is proposed by introducing a dc input current control to realize high-frequency resistance measurement and normal drive control simultaneously, without using extra dc-dc converter. On the basis of the revealed energy exchange principles among electrical ports and mechanical port of the dual-winding motor, the load ripple caused by high-frequency current perturbation is optimized based on the q-axis current distribution between two winding sets. The decoupling control algorithm for the coupling effect within and across windings is also discussed to improve the dynamic response during high-frequency resistance measurement. Finally, simulation results verify the effectiveness and improvement of the proposed method. Fast Fourier transform results indicated that the total harmonic distortion of the dc input current was reduced from 22.53% to 4.47% of the fundamental, and the torque ripple was suppressed from about ±4.5 Nm to ±0.5 Nm at the given operation points.

5.
Sensors (Basel) ; 22(2)2022 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-35062390

RESUMEN

The structured road is a scene with high interaction between vehicles, but due to the high uncertainty of behavior, the prediction of vehicle interaction behavior is still a challenge. This prediction is significant for controlling the ego-vehicle. We propose an interaction behavior prediction model based on vehicle cluster (VC) by self-attention (VC-Attention) to improve the prediction performance. Firstly, a five-vehicle based cluster structure is designed to extract the interactive features between ego-vehicle and target vehicle, such as Deceleration Rate to Avoid a Crash (DRAC) and the lane gap. In addition, the proposed model utilizes the sliding window algorithm to extract VC behavior information. Then the temporal characteristics of the three interactive features mentioned above will be caught by two layers of self-attention encoder with six heads respectively. Finally, target vehicle's future behavior will be predicted by a sub-network consists of a fully connected layer and SoftMax module. The experimental results show that this method has achieved accuracy, precision, recall, and F1 score of more than 92% and time to event of 2.9 s on a Next Generation Simulation (NGSIM) dataset. It accurately predicts the interactive behaviors in class-imbalance prediction and adapts to various driving scenarios.

6.
Sensors (Basel) ; 22(12)2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35746289

RESUMEN

In this paper, a novel near-field high-resolution image focusing technique is proposed. With the emergence of Millimeter-wave (mmWave) devices, near-field synthetic aperture radar (SAR) imaging is widely used in automotive-mounted SAR imaging, UAV imaging, concealed threat detection, etc. Current research is mainly confined to the laboratory environment, thus ignoring the adverse effects of the non-ideal experimental environment on imaging and subsequent detection in real scenarios. To address this problem, we propose an optimized Back-Projection Algorithm (BPA) that considers the loss path of signal propagation among space by converting the amplitude factor in the echo model into a beam-weighting. The proposed algorithm is an image focusing algorithm for arbitrary and irregular arrays, and effectively mitigates sparse array imaging ghosts. We apply the 3DRIED dataset to construct image datasets for target detection, comparing the kappa coefficients of the proposed scheme with those obtained from classic BPA and Range Migration Algorithm (RMA) with amplitude loss compensation. The results show that the proposed algorithm attains a high-fidelity image reconstruction focus.

7.
J Am Chem Soc ; 143(29): 11063-11071, 2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34264661

RESUMEN

Lithium-sulfur (Li-S) batteries have a high theoretical specific energy; however, their performance is plagued by the shuttle effect of lithium polysulfides and the instability of the lithium anode interface. Great efforts have been made using electrolyte additives to address the issues. Herein, we report a class of electrolyte additives, i.e., benzenedithiols (BDTs). Among the three isomers of BDTs, 1,4-BDT shows the best effect on the performance improvement of a Li-S battery because it can bond more sulfur atoms than the other two. The functionality of 1,4-BDT on the cathode and anode involves the chemical reactions of thiol groups. The S-S bonds were generated from 1,4-BDT and sulfur through oligomerization, which change the original redox path of sulfur and inhibit the shuttle effect of lithium polysulfides. In addition, 1,4-BDT can form a smooth and stable solid-electrolyte interphase (SEI), which can enable the Li/Li symmetric cell with an ultralow overpotential of 0.08 V at a high current density of 5 mA cm-2 for over 300 h. The Li-S cell with 1,4-BDT displays the highest cycling stability at a C/5 rate, with an initial capacity of 1548.5 mAh g-1 and a reversible capacity of 1306.9 mAh g-1 after 200 cycles. The Li-S pouch cell with 1,4-BDT and 2.8 g of sulfur exhibits an initial capacity of 2640 mAh and a capacity retention rate of 84.2% after 26 cycles at a C/10 rate. This work demonstrates that organodithiol compounds can be used as functional electrolyte additives and provides a new direction to design materials for advanced Li-S batteries.

8.
J Gene Med ; 23(11): e3375, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34164868

RESUMEN

BACKGROUND: Nasopharyngeal carcinoma (NPC), an Epstein-Barr virus (EBV) associated cancer, exhibits an extremely high incidence in southern Chinese. Given that human leukocyte antigen (HLA) plays critical roles in antigen presentation and relates to NPC susceptibility, it is speculated that certain HLA variants may affect EBV reactivation, which is a key pathogenic factor of NPC. Therefore, we attempted to identify HLA alleles associated with the indicator of EBV reactivation, Zta-IgA, in healthy males from NPC endemic area. METHODS: HLA alleles of 1078 healthy males in southern China from the 21-RCCP study were imputed using genome-wide single nucleotide polymorphism data. EBV Zta-IgA in blood samples were measured using an enzyme-linked immunosorbent assay. Multiple logistic regression analysis was used to evaluate the effect of HLA allele on Zta-IgA serological status and its potential joint association with smoking. The binding affinity for Zta-peptide was predicted using NetMHCIIpan 4.0. RESULTS: HLA-DRB1*09:01 was found to be associated with a higher risk of Zta-IgA seropositivity (odds ratio = 1.80, 95% confidence interval = 1.32-2.45; p = 1.82 × 10-4 ). Compared with non-smokers without HLA-DRB1*09:01, the effect size increased to 2.19- and 3.70-fold for the light and heavy smokers carrying HLA-DRB1*09:01, respectively. Furthermore, HLA-DRB1*09:01 showed a stronger binding affinity to Zta peptide than other HLA-DRB1 alleles. CONCLUSIONS: Our study highlighted the pivotal role of genetic HLA variants in EBV reactivation and the etiology of NPC. Smokers with HLA-DRB1*09:01 have a significantly higher risk of being Zta-IgA seropositive, which indicates the necessity of smoking cessation in certain high-risk populations and also provide clues for further research on the etiology of NPC.


Asunto(s)
Infecciones por Virus de Epstein-Barr/inmunología , Antígenos HLA/genética , Herpesvirus Humano 4/inmunología , Inmunoglobulina A/inmunología , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/inmunología , Transactivadores/inmunología , Adulto , Alelos , Anticuerpos Antivirales/inmunología , Pueblo Asiatico/genética , Infecciones por Virus de Epstein-Barr/virología , Estudio de Asociación del Genoma Completo/métodos , Genotipo , Voluntarios Sanos , Humanos , Inmunoglobulina A/sangre , Masculino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/inmunología , Fumar/efectos adversos , Proteínas Virales/inmunología
9.
BMC Med ; 19(1): 250, 2021 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-34689777

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is the leading cause of cancer death worldwide. Screening is a confirmed way to reduce the incidence and mortality rates of CRC. This study aimed to identify a fecal-based, noninvasive, and accurate method for detection of colorectal cancer (CRC) and advanced adenoma (AA). METHODS: Through detection in tissue (n = 96) and fecal samples (n = 88) and tested in an independent group of fecal samples (n = 294), the methylated DNA marker ITGA4 and bacterial markers Fusobacterium nucleatum (Fn) and Pepetostreptococcusanaerobius (Pa) were identified from the candidate biomarkers for CRC and AA detection. A prediction score (pd-score) was constructed using the selected markers and fecal immunochemical test (FIT) for distinguishing AA and CRC from healthy subjects by logistic regression method. The diagnostic performance of the pd-score was compared with FIT and validated in the external validation cohort (n = 117) and in a large CRC screening cohort. RESULTS: The pd-score accurately identified AA and CRC from healthy subjects with an area under the curve (AUC) of 0.958, at a specificity of 91.37%; the pd-score showed sensitivities of 95.38% for CRC and 70.83% for AA, respectively. In the external validation cohort, the sensitivities of the pd-score for CRC and AA detection were 94.03% and 80.00%, respectively. When applied in screening, the pd-score identified 100% (11/11) of CRC and 70.83% (17/24) of AA in participants with both colonoscopy results and qualified fecal samples, showing an improvement by 41.19% compared to FIT. CONCLUSIONS: The current study developed a noninvasive and well-validated approach for AA and CRC detection, which could be applied widely as a diagnostic and screening test.


Asunto(s)
Adenoma , Neoplasias Colorrectales , Adenoma/diagnóstico , Estudios de Casos y Controles , Estudios de Cohortes , Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer , Humanos
10.
Sensors (Basel) ; 21(9)2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33925864

RESUMEN

There are many small objects in traffic scenes, but due to their low resolution and limited information, their detection is still a challenge. Small object detection is very important for the understanding of traffic scene environments. To improve the detection accuracy of small objects in traffic scenes, we propose a small object detection method in traffic scenes based on attention feature fusion. First, a multi-scale channel attention block (MS-CAB) is designed, which uses local and global scales to aggregate the effective information of the feature maps. Based on this block, an attention feature fusion block (AFFB) is proposed, which can better integrate contextual information from different layers. Finally, the AFFB is used to replace the linear fusion module in the object detection network and obtain the final network structure. The experimental results show that, compared to the benchmark model YOLOv5s, this method has achieved a higher mean Average Precison (mAP) under the premise of ensuring real-time performance. It increases the mAP of all objects by 0.9 percentage points on the validation set of the traffic scene dataset BDD100K, and at the same time, increases the mAP of small objects by 3.5%.

11.
Water Sci Technol ; 84(9): 2380-2393, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34810318

RESUMEN

Novel polyvinylidene fluoride/TiO2/UiO-66-NH2 (PVDF/TiUN) membranes were produced by the delay phase separation method via introducing the TiO2/UiO-66-NH2 (TiUN) nanocomposite into PVDF casting solution. Interconnection of TiO2 and UiO-66-NH2 improved photocatalysis capacity and endowed PVDF/TiUN membranes with self-cleaning capability. Quantitative measurements showed that, firstly, PVDF/TiUN membranes exhibited improved photodegradation kinetics and efficiency (up to 88.1%) to Rhodamine B (RhB). Secondly, the performances of bovine serum albumin (BSA) rejection and permeation of PVDF/TiUN membranes outperformed those of other check samples, indicating enhanced hydrophilicity. Thirdly, rejection rate of BSA reached a breathtaking 98.14% and flux recovery ratio (FRR) of BSA reached a breathtaking 95.37%. Thus, given their excellent anti-contamination property and separation performance, the PVDF/TiUN membrane is very likely to be a novel water treatment membrane.


Asunto(s)
Incrustaciones Biológicas , Estructuras Metalorgánicas , Incrustaciones Biológicas/prevención & control , Membranas Artificiales , Polivinilos , Titanio , Circonio
12.
BMC Plant Biol ; 20(1): 69, 2020 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-32046649

RESUMEN

BACKGROUND: Acetolactate synthase (ALS)-inhibiting herbicides from the chemical families of sulfonylureas and imidazolinones are used worldwide. However, drift or sprayer contamination from some sulfonylurea herbicides causes a high level of male sterility in cruciferous species, especially oilseed rape (OSR). In this paper, we evaluated the gametocidal effects of 27 ALS-inhibiting herbicides that were sprayed on OSR plants at the bolting stage. RESULTS: OSR anther development was very sensitive to sublethal exposure to most ALS-inhibiting herbicides. The application of 18 out of the 20 tested sulfonylureas (except ethametsulfuron and ethoxysulfuron), two imidazolinones (imazethapyr and imazamox), and one sulfonylamino-carbonyltriazolinone (flucarbazone-sodium) at suitable rates could induce male sterility. Eight of the herbicides, including chlorsulfuron (at application rates of 60-120 mg/ha), halosulfuron-methyl (300-600 mg/ha), sulfosulfuron (400-600 mg/ha), triflusulfuron-methyl (500-750 mg/ha), pyrazosulfuron-ethyl (150-225 mg/ha), nicosulfuron (200-300 mg/ha), imazethapyr (750-1125 mg/ha), and imazamox (400-800 mg/ha), could induce over 90% male sterility and over 60% relative outcrossed seed set in six cultivars with different origins. These eight chemicals could be used as new gametocides for hybrid seed production. This study also examined the possibility of external application of these gametocides on several unstable Polima cytoplasmic male sterile and thermosensitive genic male sterile lines. Although the outcrossed seed set of the treated lines was slightly reduced, the gametocide application significantly increased the seed purity of the resulting hybrid. CONCLUSION: The finding of the gametocidal effects of most sulfonylureas and imidazolinones are of great importance for developing new functions for ALS-inhibiting herbicides. The application of gametocides will also greatly promote the safe utilization of environment-sensitive male sterility in hybrid seed production. Unexpectedly, the application of three triazolopyrimidines (florasulam, flumetsulam, and penoxsulam) and one pyrimidinylthiobenzoate (bispyribac-sodium) did not cause male sterility, although these herbicides obviously inhibited the activity of ALS and plant growth. This result suggests that inhibition of ALS activity does not always lead to male sterility in plants, and these gametocides may also inhibit other biological functions vital for microspore development.


Asunto(s)
Brassica napus/efectos de los fármacos , Herbicidas/administración & dosificación , Imidazoles/administración & dosificación , Semillas/efectos de los fármacos , Compuestos de Sulfonilurea/administración & dosificación , Brassica napus/genética , Brassica napus/fisiología , Cruzamientos Genéticos , Hibridación Genética , Reproducción , Semillas/genética , Semillas/fisiología
13.
BMC Plant Biol ; 19(1): 124, 2019 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-30940071

RESUMEN

BACKGROUND: Acetolactate synthase (ALS)-inhibiting herbicide tribenuron-methyl (TBM) is an efficient gametocide that can cause rapeseed (Brassica napus L.) to become male sterile and outcrossing. To find the reason the TBM treatment leads to male sterility, an integrated study using cytological, physiological, and transcriptomic methods was conducted. RESULTS: Some temporary symptoms, including the discoloration of young leaves and a short halt of raceme elongation, were observed in the rapeseed plants exposed to TBM at an application rate of 1 µg per plant. Both chloroplasts in young leaves and plastids in anthers were deformed. TBM also reduced the leaf photosynthetic rate and the contents of chlorophyll, soluble sugar and pyruvate. Both the tapetal cells and uni-nucleate microspores in the treated plants showed large autophagic vacuoles, and the tissue degenerated quickly. A transcriptomic comparison with the control identified 200 upregulated and 163 downregulated differential expression genes in the small flower buds of the TBM treatment. The genes encoding functionally important proteins, including glucan endo-1,3-beta-glucosidase A6, QUARTET3 (QRT3), ARABIDOPSIS ANTHER 7 (ATA7), non-specific lipid-transfer protein LTP11 and LTP12, histone-lysine N-methyltransferase ATXR6, spermidine coumaroyl-CoA acyltransferase (SCT), and photosystem II reaction centre protein psbB, were downregulated by TBM exposure. Some important genes encoding autophagy-related protein ATG8a and metabolic detoxification related proteins, including DTX1, DTX6, DTX35, cytosolic sulfotransferase SOT12, and six members of glutathione S-transferase, were upregulated. In addition, several genes related to hormone stimulus, such as 1-aminocyclopropane-1-carboxylate synthase 8 (ACS8), ethylene-responsive factor ERF1A, ERF1, ERF71, CRF6, and RAP2-3, were also upregulated. The transcriptional regulation is in accordance with the functional abnormalities of pollen wall formation, lipid metabolism, chloroplast structure, ethylene generation, cell cycle, and tissue autophagy. CONCLUSION: The results suggested that except for ALS, the metabolic pathways related to lipid metabolism, pollen exine formation, photosynthesis and hormone response are associated with male sterility induced by TBM. The results provide new insight into the molecular mechanisms of inducing male sterility by sulfonylurea.


Asunto(s)
Acetolactato Sintasa/antagonistas & inhibidores , Arilsulfonatos/farmacología , Brassica napus/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Herbicidas/farmacología , Infertilidad Vegetal/efectos de los fármacos , Acetolactato Sintasa/metabolismo , Brassica napus/enzimología , Brassica napus/fisiología , Regulación hacia Abajo/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/enzimología , Hojas de la Planta/fisiología , Proteínas de Plantas/antagonistas & inhibidores , Proteínas de Plantas/metabolismo
14.
Entropy (Basel) ; 20(4)2018 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-33265321

RESUMEN

Chaotic systems with hyperbolic sine nonlinearity have attracted the attention of researchers in the last two years. This paper introduces a new approach for generating a class of simple chaotic systems with hyperbolic sine. With nth-order ordinary differential equations (ODEs), any desirable order of chaotic systems with hyperbolic sine nonlinearity can be easily constructed. Fourth-order, fifth-order, and tenth-order chaotic systems are taken as examples to verify the theory. To achieve simplicity of the electrical circuit, two back-to-back diodes represent hyperbolic sine nonlinearity without any multiplier or subcircuits. Thus, these systems can achieve both physical simplicity and analytic complexity at the same time.

15.
Biotechnol Appl Biochem ; 63(4): 595-600, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25952742

RESUMEN

A Cr(VI)-reducing Mangrovibacter plantisponsor strain, CR1, was isolated from tannery effluent sludge and had quinone respiration characteristics. Its chromate (CrO4 (2-) ) resistance, quinone respiration characteristics, and Cr(VI) reduction efficiencies were evaluated in detail. Strain CR1 exhibited a high Cr(VI) resistance with a minimal inhibitory concentration (MIC) of 32 mM in LB medium, and its quinone respiration could occur when an electron donor and strain CR1 both existed in the reaction system. Cr(VI) reduction by strain CR1 was significantly enhanced by a factor of 0.4-4.3 with five different quinone compounds: anthraquinone-2,7-disulfonate, anthraquinone-1-sulfonate, anthraquinone-2-sulfonate (AQS), anthraquinone-2,6-disulfonate, and anthraquinone-1,5-disulfonate. AQS was the best electron shuttle among them, and the greatest enhancement to the Cr(VI) bio-reduction was achieved with 0.96 mM AQS. The correlation between the reaction constant k (mg Cr(VI) g(-1) dry cell weight H(-1) ) and thermodynamic temperature T (K) was expressed as an Arrhenius equation lnk=-7662.9/T+27.931(R2=0.9486); the activation energy Ea was 63.71 kJ mol(-1) , and the pre-exponential factor A was 1.35 × 10(12)  mg Cr(VI) g(-1) dry cell weight H(-1) . During the Cr(VI) reduction process, the pH tended to become neutral, and the oxidation-reduction potential decreased to -440 mV. The efficient reduction of Cr(VI) mediated by a quinone respiration strain shows potential for the rapid anaerobic removal of Cr(VI).


Asunto(s)
Benzoquinonas/metabolismo , Cromo/aislamiento & purificación , Cromo/metabolismo , Enterobacteriaceae/metabolismo , Contaminantes Ambientales/aislamiento & purificación , Contaminantes Ambientales/metabolismo , Benzoquinonas/farmacología , Biodegradación Ambiental , Enterobacteriaceae/efectos de los fármacos , Concentración de Iones de Hidrógeno , Oxidación-Reducción/efectos de los fármacos , Temperatura
16.
Water Environ Res ; 88(11): 2132-2141, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28661329

RESUMEN

One-dimensional column and two-dimensional tank experiments were carried out to determine (1) the physics of foam flow and propagation of foaming gas, foaming liquid, and foam; (2) the pressure distribution along foam flow and the effect of media permeability, foam flow rate and foam quality on foam injection pressure; and (3) the migration and distribution property of foam flow in homogeneous and heterogeneous sediments. The results demonstrated that: (1) gas and liquid front were formed ahead of the foam flow front, the transport speed order is foaming gas > foaming liquid > foam flowing; (2) injection pressure mainly comes from the resistance to bubble migration. Effect of media permeability on foam injection pressure mainly depends on the physics and behavior of foam flow; (3) foam has a stronger capacity of lateral spreading, besides, foam flow was uniformly distributed across the foam-occupied region, regardless of the heterogeneity of porous media.


Asunto(s)
Dodecil Sulfato de Sodio/química , Contaminantes del Suelo/química , Suelo/química , Tensoactivos/química , Propiedades de Superficie , Agua/química
17.
Water Sci Technol ; 71(6): 848-55, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25812093

RESUMEN

Electrochemical oxidation of Acid Red 3R (AR3R) was investigated with the new catalyst of iron phosphomolybdate (FePMo12) supported on modified molecular sieves type 4 Å (4A) as packing materials in the reactor. The results of the Fourier transform infrared spectroscopy and X-ray diffraction indicated that the heteropolyanion had a Keggin structure. The optimal conditions for decolorization of simulated AR3R wastewater were as follows: current density 35 mA/cm², initial pH 4.0, airflow 0.08 m³/hour and inter-electrode distance 3.0 cm. With the addition of NaCl to the system, the decolorization efficiency increased. But Na2SO4had a negative effect on the decolorization efficiency, which was attributed to the negative salt effect. The degradation mechanisms of AR3R were also discussed in detail.


Asunto(s)
Eritrosina/química , Colorantes Fluorescentes/química , Molibdeno/química , Ácidos Fosfóricos/química , Contaminantes Químicos del Agua/química , Técnicas Electroquímicas , Hierro/química , Oxidación-Reducción , Espectroscopía Infrarroja por Transformada de Fourier , Aguas Residuales/análisis , Difracción de Rayos X
18.
Biodegradation ; 25(3): 395-404, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24179089

RESUMEN

The biocatalyzing effect of a novel cellulose acetate immobilized redox mediators technology (CE-RM) on nitrite denitrification process was studied with anthraquinone, 1,8-dichloroanthraquinone, 1,5-dichloroanthraquinone and 1,4,5,8-tetrachloroanthraquinone. The results showed that the immobilized 1,4,5,8-tetrachloroanthraquinone presented the best biocatalyzed effect which increased nitrite denitrification rate to 2.3-fold with 12 mmol/L 1,4,5,8-tetrachloroanthraquinone. The unequal biocatalyzing effect was due to the quantity and position of -Cl substituent in anthraquinone-structure. Moreover, the nitrite denitrification rate was increased with the oxidation reduction potential (ORP) values becoming more negative during the biocatalyzing process. The stabilized ORP value with 12 mmol/L immobilized 1,4,5,8-tetrachloroanthraquinone were 81 mV lower than the control. At the same time, the more OH(-) was produced with the higher nitrite removal rate achieved in the nitrite denitrification process. In addition, a positive linear correlation was found between the nitrite removal reaction constants k [gNO2(-)-N/(gVSS d)] and immobilized 1,4,5,8-tetrachloroanthraquinone concentration (C1,4,5,8-tetrachloroanthraquinone), which was k = 1.8443 C1,4,5,8-tetrachloroanthraquinone + 33.75(R(2) = 0.9411). The initial nitrite concentration of 179 mgNO2(-)-N/L resulted in the maximum nitrite removal rate, which was 6.526[gNO2(-)-N/(gVSS d)]. These results show that the application of cellulose acetate immobilized redox mediators (CE-RM) can be valuable for increasing nitrite denitrification rate.


Asunto(s)
Antraquinonas/química , Celulosa/análogos & derivados , Consorcios Microbianos/fisiología , Nitritos/química , Contaminantes Químicos del Agua/química , Biocatálisis , Biodegradación Ambiental , Celulosa/química , Desnitrificación , Técnicas Electroquímicas , Cinética , Nitritos/metabolismo , Oxidación-Reducción , Relación Estructura-Actividad , Aguas Residuales/química , Contaminantes Químicos del Agua/metabolismo
19.
Biotechnol Biotechnol Equip ; 28(1): 38-42, 2014 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-27594796

RESUMEN

In this paper, the effect of NaCl and Na2SO4 on the biodecolourization of reactive brilliant red K-2BP by a Halomonas sp. GYW (EF188281) was investigated in details. The decolourisation efficiency and the oxidation-reduction potential (ORP) change were explored during the decolourization process. The results from sequencing batch tests showed that Na2SO4 influenced the decolourization efficiency more slightly than NaCl in different synthetic dye solutions with different mixtures of Na2SO4 and NaCl. In the dye solutions with the same salt concentration or the same Na+ concentration, high Na2SO4 concentration did not inhibit the decolourization process and even stimulated the decolourization efficiency of reactive brilliant red K-2BP. Compared to NaCl system, the addition of Na2SO4 increased the ORP values about 35 mV, which agreed with the theoretic analysis of Gibbs function. This study improved our knowledge of azo dye decolourization under high salinity conditions and provided efficient option for the treatment of azo dye wastewater.

20.
Sci Rep ; 14(1): 8125, 2024 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-38582956

RESUMEN

CD74 is a type-II transmembrane glycoprotein that has been linked to tumorigenesis. However, this association was based only on phenotypic studies, and, to date, no in-depth mechanistic studies have been conducted. In this study, combined with a multi-omics study, CD74 levels were significantly upregulated in most cancers relative to normal tissues and were found to be predictive of prognosis. Elevated CD74 expression was associated with reduced levels of mismatch-repair genes and homologous repair gene signatures in over 10 tumor types. Multiple fluorescence staining and bulk, spatial, single-cell transcriptional analyses indicated its potential as a marker for M1 macrophage infiltration in pan-cancer. In addition, CD74 expression was higher in BRCA patients responsive to conventional chemotherapy and was able to predict the prognosis of these patients. Potential CD74-activating drugs (HNHA and BRD-K55186349) were identified through molecular docking to CD74. The findings indicate activation of CD74 may have potential in tumor immunotherapy.


Asunto(s)
Macrófagos , Neoplasias , Humanos , Pronóstico , Simulación del Acoplamiento Molecular , Macrófagos/metabolismo , Neoplasias/genética , Neoplasias/metabolismo
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