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1.
Small ; : e2400939, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38618653

RESUMO

Heterodimers of metal nanocrystals (NCs) with tailored elemental distribution have emerged as promising candidates in the field of electrocatalysis, owing to their unique structures featuring heterogeneous interfaces with distinct components. Despite this, the rational synthesis of heterodimer NCs with similar elemental composition remains a formidable challenge, and their impact on electrocatalysis has remained largely elusive. In this study, Pd@Bi-PdBi heterodimer NCs are synthesized through an underpotential deposition (UPD)-directed growth pathway. In this pathway, the UPD of Bi promotes a Volmer-Weber growth mode, allowing for judicious modulation of core-satellite to heterodimer structures through careful control of supersaturation and growth kinetics. Significantly, the heterodimer NCs are employed in the electrocatalytic process of ethylene glycol (EG) with high activity and selectivity. Compared with pristine Pd octahedra and common PdBi alloy NC, the unique heterodimer structure of the Pd@Bi-PdBi heterodimer NCs endows them with the highest electrocatalytic performance of EG and the best selectivity (≈93%) in oxidizing EG to glycolic acid (GA). Taken together, this work not only heralds a new strategy for UPD-directed synthesis of bimetallic NCs, but also provides a new design paradigm for steering the selectivity of electrocatalysts.

2.
Sci Rep ; 14(1): 5582, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38448540

RESUMO

This study presents a data-driven assisted real-time optimization model which is an innovative approach to address the challenges posed by integrating Submerged Arc Furnace (SAF) systems with renewable energy sources, specifically photovoltaic (PV) and wind power, with modern intelligent energy terminals. Specifically, the proposed method is divided into two stages. The first stage is related to data-driven prediction for addressing local time-varying renewable energy and electricity market prices with predicted information, and the second stage uses an optimization model for real-time SAF dispatch. Connections between intelligent energy terminals, demand-side devices, and load management systems are established to enhance local renewable resource utilization. Additionally, mathematical formulations of the operating resistance in SAF are explored, and deep neuron networks are employed and modified for dynamic uncertainty prediction. The proposed approach is validated through a case study involving an intelligent energy terminal with a 12.5 MVA SAF system and 12 MW capacity renewable generators in an electricity market with fluctuating prices. The findings of this research underscore the efficacy of the proposed optimization model in reducing operational costs and enhancing the utilization of localized renewable energy generation. By integrating four distinct dissatisfaction coefficients into the optimization framework, we demonstrate the model's adaptability and efficiency. The application of the optimization strategy delineated herein results in the SAF system's profitability oscillating between $111 and $416 across various time intervals, contingent upon the coefficient settings. Remarkably, an aggregate daily loss recovery amounting to $1,906.84 can be realized during the optimization period. Such outcomes not only signify considerable economic advantages but also contribute to grid stability and the diminution of renewable energy curtailment, thereby underscoring the dual benefits of economic efficiency and sustainability in energy management practices.

3.
J Am Chem Soc ; 145(49): 26711-26719, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38031299

RESUMO

In situ and accurate measurement of the structure and dynamics of interfacial water in the hydrogen evolution reaction (HER) is a well-known challenge because of the coupling of water among varied structures and its dual role as reactants and solvents. Further, the interference of bulk water and intricate interfacial interactions always hinders the probing of interfacial water. Surface-enhanced infrared absorption spectroscopy is extremely sensitive for the measurement of interfacial water; herein, we develop a nanoconfinement strategy by introducing nonaqueous ionic liquids to decouple and tailor the water structure in the electric double layer and further combined with molecular dynamics simulations, successfully gaining the correlation between isolated water, water clusters, and the water network with HER activity. Our results clearly disclosed that the potential-dependent asymmetric four-coordinated water network, whose connectivity could be regulated by hydrophilic and hydrophobic cations, was positively correlated with HER activity, which provided a pioneering guidance framework for revealing the function of water in catalysis, energy, and surface science.

4.
J Am Chem Soc ; 145(47): 25695-25704, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37943722

RESUMO

In the energy conversion context, the design and synthesis of high-performance metal-free carbon nanomaterials with topological defects for the oxygen reduction reaction (ORR) are essential. Herein, we first report a template-assisted strategy to fabricate carbon defect electrocatalysts with rich vacancy coupling pentagons (VP) as active sites in two-dimensional (2D) carbon nanosheets (VP/CNs). Experimental characterizations verify the presence of abundant VP active sites in the VP/CNs electrocatalyst, and the ORR activity is linearly related to the amounts of VP active sites. In situ spectroscopic results identify that the VP/CNs can catalyze direct O-O bond cleavage, bypassing the formation of traditional *OOH intermediates, resulting in the fast kinetics of ORR via a dissociative pathway. The as-prepared VP/CNs show outstanding intrinsic activity for alkaline ORR (half-wave potential of 0.86 V vs reversible hydrogen electrode) with an almost 99% efficiency for four-electron selectivity, outperforming that using the benchmark of Pt/C. Density functional theory calculations further reveal that the cooperative effect between carbon vacancy and adjacent pentagons significantly increases the charge transfer and achieves a lower ORR reaction energy barrier compared with the counterpart of adjacent pentagons or single pentagon. The well-designed carbon defects pave a new avenue for the rational design of metal-free electrocatalysts with high efficiency.

5.
BMC Musculoskelet Disord ; 24(1): 881, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37953269

RESUMO

PURPOSE: This study was to investigate the feasibility and treatment effect of using modified Kirschner wire (K-wire) percutaneous rotation prying reduction combined with Elastic Stable Intramedullary Nailing (ESIN) in children with Judet IV radial neck fracture. METHODS: A retrospective analysis was conducted on 47 children with Judet IV radial neck fracture who underwent treatment with modified K-wire percutaneous rotation prying reduction combined with ESIN from April 2019 to November 2022, including 25 males and 22 females, with an average age of 8.79 years old (ranging from 5 to 14). The study recorded the surgical time, fluoroscopy time, reduction time, and reduction quality evaluated according to the Metaizeau radiological standard. During the last follow-up, the flexion-extension and forearm rotation function of the affected and healthy sides were recorded, and the Mayo Elbow Performance index was used to evaluate the elbow joint function. RESULTS: The average duration of the operation was 25.51 min (ranging from 14 to 43 min), with a mode of 2 reset times (ranging from 1 to 5) and 8 fluoroscopic times (ranging from 4 to 15). Based on the Metaizeau radiological standard for assessing reduction quality, 45 cases were deemed excellent, while 2 cases were considered good. Following 3-4 weeks of postoperative long-arm cast immobilization, exercises were performed to promote elbow joint and forearm rotation. The ESIN was removed after satisfactory fracture healing around 4 months postoperatively. The average follow-up period was 26.79 months (ranging from 5 to 48). At the final follow-up, the range of motion for the affected limb in flexion, extension, pronation, and supination was (140.23 ± 4.80)°, (4.43 ± 3.98)°, (84.09 ± 4.97)°, and (83.83 ± 4.55)°, respectively. There was no statistically significant difference compared to the healthy side, which had a range of motion of (141.36 ± 3.27)°, (5.28 ± 2.25)°, (85.66 ± 3.20)°, and (84.98 ± 2.57)° (P > 0.05). According to the Mayo Elbow Performance index, 44 cases were rated as excellent and 1 case was considered good. CONCLUSION: The modified K-wire percutaneous rotation prying reduction combined with ESIN is an effective treatment for severe radial neck fractures in children. This technique offers several advantages, including the ability to easily "capture" significantly displaced radial heads, achieve rapid and accurate reduction, and reduce radiation exposure.


Assuntos
Fixação Intramedular de Fraturas , Fraturas da Cabeça e do Colo do Rádio , Fraturas do Rádio , Masculino , Feminino , Humanos , Criança , Fios Ortopédicos , Fixação Intramedular de Fraturas/métodos , Pinos Ortopédicos , Estudos Retrospectivos , Resultado do Tratamento , Fixação Interna de Fraturas/métodos , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Extremidade Superior , Amplitude de Movimento Articular
6.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(10): 1214-1219, 2023 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-37848315

RESUMO

Objective: To explore the feasibility and early effectiveness of computer-simulated osteotomy based on the health-side combined with guide plate technique in the treatment of cubitus varus deformity in adolescents. Methods: The clinical data of 23 patients with cubitus varus deformity who met the selection criteria between June 2019 and February 2023 were retrospectively analyzed. There were 17 males and 6 females, ranging in age from 4 to 16 years with an average of 8.5 years. The time from injury to operation was 1-4 years. The angle of distal humerus rotation was defined by humeral head posterior inclination angle using low radiation dose CT to scan the patient's upper extremity data at one time, and the preoperative rotation of the distal humerus on the affected side was (33.82±4.39)°. The CT plain scan data were imported into 9yuan3D digital orthopaedic system (V3.34 software) to reconstruct three-dimensional images of both upper extremities. The simulated operation was performed with the healthy upper extremity as the reference, the best osteotomy scheme was planned, overlapped and compared, and the osteotomy guide plate was prepared. The patients were followed up regularly after operation, and the formation of callus in the osteotomy area was observed by X-ray examination. Before and after operation, the carrying angle of both upper extremities (the angle of cubitus valgus was positive, and the angle of cubitus varus was negative) and anteversion angle were measured on X-ray and CT images. At the same time, the flexion and extension range of motion of elbow joint and the external rotation range of motion of upper extremity were measured, and Mayo score was used to evaluate the function of elbow joint. Results: The operation time ranged from 34 to 46 minutes, with an average of 39 minutes. All patients were followed up 5-26 months, with a mean of 14.9 months. All the incisions healed by first intention after the operation; 2 patients had nail path irritation symptoms after Kirschner wire fixation, which improved after dressing change; no complication such as breakage and loosening of internal fixators occurred after regular X-ray review. Continuous callus formed at the osteotomy end at 4 weeks after operation, and the osteotomy end healed at 8-12 weeks after operation. At last follow-up, the carrying angle, anteversion angle, external rotation range of motion, and extension and flexion range of motion of the elbow joint of the affected side significantly improved when compared with preoperative ones ( P<0.05). Except for the extension range of motion of the healthy elbow joint ( P<0.05), there was no significant difference in other indicators between the two sides ( P>0.05). At last follow-up, the Mayo elbow score was 85-100, with an average of 99.3; 22 cases were excellent, 1 case was good, and the excellent and good rate was 100%. Conclusion: Computer-simulated osteotomy based on health-side combined with guide plate technique for treating cubitus varus deformity in adolescents can achieve precise osteotomy, which has the advantages of short operation time and easy operation, and the short-term effectiveness is satisfactory.


Assuntos
Articulação do Cotovelo , Fraturas do Úmero , Deformidades Articulares Adquiridas , Deformidades Congênitas dos Membros , Masculino , Feminino , Humanos , Adolescente , Pré-Escolar , Criança , Cotovelo , Fraturas do Úmero/cirurgia , Estudos Retrospectivos , Deformidades Articulares Adquiridas/etiologia , Deformidades Articulares Adquiridas/cirurgia , Articulação do Cotovelo/cirurgia , Osteotomia/métodos , Cabeça do Úmero , Amplitude de Movimento Articular , Computadores , Resultado do Tratamento
7.
J Orthop Surg Res ; 18(1): 595, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37568239

RESUMO

PURPOSE: This study aims to evaluate the feasibility of using ultrasound-guided Kirschner wire or elastic intramedullary nail for fixation in the treatment of acute Monteggia fracture in children. METHODS: A retrospective analysis was conducted on 31 cases of acute Monteggia fracture in children treated with ultrasound-guided Kirschner wire or elastic intramedullary nail fixation between April 2020 and December 2022, including 14 cases of Kirschner wire fixation and 17 cases of elastic intramedullary nail fixation. During the operation, soft tissue compression and nerve and vascular injuries were explored, fracture reduction was performed under ultrasound guidance, and operation time was recorded. After the operation, X-ray examination was conducted to assess the quality of fracture reduction. At the last follow-up, the flexion, extension, pronation, and supination angles of both affected and unaffected elbow joints were measured, and the Mayo score was used to evaluate elbow joint function. RESULTS: The average duration of surgery was 50.16 ± 19.21 min (ranging from 20 to 100 min). Based on the evaluation criteria for assessing reduction quality, 28 cases were deemed excellent, while 3 cases were considered good. After immobilization with long-arm cast for 4-6 weeks postoperatively, elbow and forearm rotation exercises were performed. Kirschner wires were removed after an average of 6.64 ± 0.93 weeks (ranging from 6 to 9 weeks) postoperatively, and elastic intramedullary nails were removed after an average of 5.12 ± 1.54 months (ranging from 4 to 10 months) postoperatively. The average follow-up time was 19.13 ± 11.22 months (ranging from 4 to 36 months). During the final follow-up, the affected limb's range of motion in flexion, extension, pronation, and supination was (141.16 ± 4.24)°, (4.61 ± 2.81)°, (84.52 ± 3.74)°, and (84.23 ± 3.69)°, respectively. There was no notable variance when compared to the healthy limb, which had a range of motion of (141.81 ± 2.99)°, (4.81 ± 2.50)°, (85.61 ± 3.12)°, and (85.03 ± 2.73)° (P > 0.05). The Mayo Elbow Performance index classified 29 cases as excellent and 2 cases as good. CONCLUSION: Ultrasound-guided Kirschner wire or elastic intramedullary nail fixation can be used for the treatment of acute Monteggia fracture in children, which can explore the surrounding nerves, blood vessels, and soft tissue compression, reduce the difficulty of reduction, and cause minimal trauma. It can greatly reduce the risk of radiation exposure and complications such as vascular and nerve injury during the operation.


Assuntos
Articulação do Cotovelo , Fratura de Monteggia , Humanos , Criança , Fratura de Monteggia/diagnóstico por imagem , Fratura de Monteggia/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Fios Ortopédicos , Articulação do Cotovelo/cirurgia , Fixação Interna de Fraturas , Amplitude de Movimento Articular
8.
Analyst ; 148(4): 869-875, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36655552

RESUMO

3,3',5,5'-tetramethylbenzidine (TMB)-H2O2 is widely used as an effective colorimetric system, in which the color reaction is implemented with peroxidase-catalyzed TMB oxidation by H2O2 that usually measured UV-vis absorption spectra or Raman spectra. However, its low accuracy significantly limits its application. Blue charge transfer complex (CTC), which is the product of TMB and H2O2 reaction and is used as the basis for partial colorimetric methods, usually causes colorimetric error owing to changes in the UV-vis absorption and Raman spectra during TMB oxidation under various environmental conditions (catalyst type, temperature, H2O2 concentration). Herein, we propose a surface-enhanced Raman spectrum (SERS)-based error calibration method to improve the accuracy of the TMB-H2O2 colorimetric system. It is found that under 633 nm laser excitation, TMB has three Raman peaks at 1189, 1335 and 1609 cm-1 in the single-electron oxidation phase, and these peaks disappear completely in the two-electron oxidation phase. By comparing these Raman peaks, we can conveniently obtain the actual process information during TMB oxidation. Using the proposed method, the accuracy of the TMB-H2O2 colorimetric system improved by more than 15%. Importantly, this SERS-based TMB-H2O2 error calibration method will open a new horizon for enzyme-linked immunosorbent assay (ELISA) and other biomedical applications.

9.
Environ Sci Ecotechnol ; 11: 100184, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36158755

RESUMO

A large number of pharmaceuticals and personal care products (PPCPs) persist in wastewater, and the consumption of PPCPs for COVID-19 control and prevention has sharply increased during the pandemic. This study investigated the occurrence, removal efficiency, and risk assessment of six typical PPCPs commonly used in China in two wastewater treatment plants (WWTPs). Ribavirin (RBV) is an effective pharmaceutical for severely ill patients with COVID-19, and the possible biodegradation pathway of RBV by activated sludge was discovered. The experimental results showed that PPCPs were detected in two WWTPs with a detection rate of 100% and concentrations ranging between 612 and 2323 ng L-1. The detection frequency and concentrations of RBV were substantially higher, with a maximum concentration of 314 ng L-1. Relatively high pollution loads were found for the following PPCPs from influent: ibuprofen > ranitidine hydrochloride > RBV > ampicillin sodium > clozapine > sulfamethoxazole. The removal efficiency of PPCPs was closely related to adsorption and biodegradation in activated sludge, and the moving bed biofilm reactor (MBBR) had a higher removal capacity than the anoxic-anaerobic-anoxic-oxic (AAAO) process. The removal efficiencies of sulfamethoxazole, ampicillin sodium, ibuprofen, and clozapine ranged from 92.21% to 97.86% in MBBR process and were relatively low, from 61.82% to 97.62% in AAAO process, and the removal of RBV and ranitidine hydrochloride were lower than 42.96% in both MBBR and AAAO processes. The discrepancy in removal efficiency is caused by temperature, hydrophilicity, and hydrophobicity of the compound, and acidity and alkalinity. The transformation products of RBV in activated sludge were detected and identified, and the biodegradation process of RBV could be speculated as follows: first breaks into TCONH2 and an oxygen-containing five-membered heterocyclic ring under the nucleosidase reaction, and then TCONH2 is finally formed into TCOOH through amide hydrolysis. Aquatic ecological risks based on risk quotient (RQ) assessment showed that PPCPs had high and medium risks in the influent, and the RQ values were all reduced after MBBR and AAAO treatment. Ranitidine hydrochloride and clozapine still showed high and medium risks in the effluent, respectively, and thus presented potential risks to the aquatic ecosystem.

10.
Sensors (Basel) ; 22(4)2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35214511

RESUMO

Soil moisture content (SMC) plays an essential role in geoscience research. The SMC can be retrieved using an artificial neural network (ANN) based on remote sensing data. The quantity and quality of samples for ANN training and testing are two critical factors that affect the SMC retrieving results. This study focused on sample optimization in both quantity and quality. On the one hand, a sparse sample exploitation (SSE) method was developed to solve the problem of sample scarcity, resultant from cloud obstruction in optical images and the malfunction of in situ SMC-measuring instruments. With this method, data typically excluded in conventional approaches can be adequately employed. On the other hand, apart from the basic input parameters commonly discussed in previous studies, a couple of new parameters were optimized to improve the feature description. The Sentinel-1 SAR and Landsat-8 images were adopted to retrieve SMC in the study area in eastern Austria. By the SSE method, the number of available samples increased from 264 to 635 for ANN training and testing, and the retrieval accuracy could be markedly improved. Furthermore, the optimized parameters also improve the inversion effect, and the elevation was the most influential input parameter.


Assuntos
Tecnologia de Sensoriamento Remoto , Solo , Redes Neurais de Computação
11.
BMC Musculoskelet Disord ; 23(1): 155, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35172802

RESUMO

BACKGROUND: The Taylor Spatial Frame (TSF) has been widely used for tibial fracture. However, traditional radiographic measurement method is complicated and the reduction accuracy is affected by various factors. The purpose of this study was to propose a new marker- three dimensional (3D) measurement method and determine the differences of reduction outcomes, if any, between marker-3D measurement method and traditional radiographic measurement in the TSF treatment. METHODS: Forty-one patients with tibial fracture treated by TSF in our institution were retrospectively analyzed from January 2016 to June 2019, including 21 patients in the marker-3D measurement group (experimental group) and 20 patients in the traditional radiographic measurement group (control group). In the experimental group, 3D reconstruction with 6 markers installed on the TSF was performed to determine the electronic prescription. In the control group, the anteroposterior (AP) and lateral radiographs were performed for the traditional parameter measurements. The effectiveness was evaluated by the residual displacement deformity (RDD) and residual angle deformity (RAD) in the coronal and sagittal plane, according to the AP and lateral X-rays after reduction. RESULTS: All patients achieved functional reduction. The residual RDD in AP view was 0.5 (0, 1.72) mm in experimental group and 1.74 (0.43, 3.67) mm in control group. The residual RAD in AP view was 0 (0, 1.25) ° in experimental group and 1.25 (0.62, 1.95) °in control group. As for the lateral view, the RDD was 0 (0, 1.22) mm in experimental group and 2.02 (0, 3.74) mm in control group, the RAD was 0 (0, 0) ° in experimental group and 1.42 (0, 1.93) ° in control group. Significant differences in all above comparisons were observed between the two groups (AP view RDD: P = 0.024, RAD: P = 0.020; Lateral view RDD: P = 0.016, RAD: P = 0.004). CONCLUSIONS: The present study introduced a marker-3D measurement method to complement the current TSF treatment. This method avoids the manual measurement error and improves the accuracy of fracture reduction, providing potential advantages of bone healing and function rehabilitation.


Assuntos
Fraturas da Tíbia , Fixadores Externos , Fixação de Fratura , Humanos , Radiografia , Estudos Retrospectivos , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/cirurgia
12.
Talanta ; 240: 123118, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34942473

RESUMO

Hydrogen peroxide (H2O2) detection with high sensitivity plays an important role in biomedical research and food engineering. By combining colorimetry and surface enhanced Raman spectroscopy (SERS), we synthetize a novel H2O2 dual-sensor constructed via TMB-Fe3O4@AuNPs. In the presence of H2O2, the peroxide model enzyme might catalyze the oxidation of 3,3',5,5'- tetramethylbenzidine (TMB) as blue charge transfer complex (CTC) for colorimetry, and then facilitate the sensitivity improvement of SERS detection. The achieved results show that in colorimetry, the linear range is from 40 µM to 5.5 mM with the detection limit of 11.1 µM; in SERS detection, the linear range is from 2 nM to 1 µM with the detection limit of 0.275 nM. Clearly, this mutual reference strategy improves both the detection limit of colorimetry and the sensitivity of SERS detection. Moreover, this colorimetry/SERS dual-sensor constructed via TMB-Fe3O4@AuNPs is successfully applied to the H2O2 detection in plasma and milk, indicating the excellent performance and flexibility.


Assuntos
Colorimetria , Nanopartículas Metálicas , Ouro , Peróxido de Hidrogênio , Limite de Detecção , Análise Espectral Raman
13.
Front Oncol ; 11: 737760, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34568073

RESUMO

BACKGROUND: The prognostic and clinicopathological value of Ki-67 in melanoma is controversial. The purpose of this meta-analysis was to determine the prognostic role of Ki-67 in melanoma patients. MATERIALS AND METHODS: The PubMed, Cochrane Library, Web of Science, and Embase databases were searched systematically up to April 9, 2021. We calculated the pooled hazard ratios (HRs) and 95% confidence intervals (CIs) to determine the relationship between Ki-67 overexpression and survival outcomes. We also calculated the combined odds ratios (ORs) and 95% CIs to determine the relationship between Ki-67 expression levels and clinicopathologic parameters. All data were statistically analyzed by Stata 11.0. RESULTS: A total of 10 studies involving 929 patients were included in our meta-analysis. The pooled HR showed that Ki-67 overexpression was connected with poor overall survival rates (HR=2.92, 95% CI=2.17-3.91, p<0.000). However, there was no correlation between Ki-67 overexpression and the PFS (HR=0.999, 95% CI =0.958-1.041, P =0.958; I2 = 21.80%, P =0.258) or RFS (HR=1.14, 95% CI = 0.42-3.11, P =0.993; I2 = 85.00%, P =0.01) rates. Ki-67 expression levels were associated with tumor thickness, but not sex, location, ulceration or vascular invasion. CONCLUSION: Ki-67 is a useful poor prognostic indicator for melanoma patients.

14.
Huan Jing Ke Xue ; 42(7): 3555-3564, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212682

RESUMO

The spatial distribution of fertilization intensity and its influencing factors are significant for the accurate management of fertilization and pollution prevention and control. Previous studies are mostly limited to the discussion of human factors that influences the spatial distribution of fertilization intensity while ignoring natural geographical factors. Based on the chemical fertilizer survey data collected from 23492 sites in Chengdu Plain and combined with Geostatistics analysis and Geographic Information System (GIS) technology, the spatial distribution characteristics and influencing factors of average nitrogen and phosphorus fertilizer application intensity from 2010 to 2015 in this region were explored. The results show that:① the average annual application intensity of nitrogen and phosphorus fertilizer in the study area from 2010 to 2015 is generally in the low and medium risk intensity of 120-360 kg·hm-2 and 60-180 kg·hm-2. The high risk intensity is mainly distributed in the grain (fruit) and vegetable growing areas such as Pidu, Pengzhou, Shifang, Longquanyi and Jintang, while the relatively low value areas are mostly distributed in the south and northeast. ② the nugget coefficients of nitrogen and phosphorus fertilizer application intensities are 66.17% and 41.60%. Their spatial distribution is determined by structural and random factors, showing a moderate spatial autocorrelation. ③ both human and natural factors have significant effects on the application intensity of nitrogen and phosphorus fertilizer. The crop type (fine classification) can explain the spatial variation of nitrogen fertilizer and phosphorus fertilizer respectively by 12.90% and 25.10%, which is the main controlling factor affecting the spatial distribution of nitrogen and phosphorus application intensity; the importance of soil parent material is second only to the planting crop type, and the independent explanation ability of phosphorus application intensity is about 3.6 times higher than that of nitrogen application intensity. When the type of planting crop plays a decisive role, the soil parent material still deeply restricts and affects the spatial distribution of nitrogen and phosphorus fertilizer application intensity in the study area. Therefore, the comprehensive effects of planting crop types and soil parent materials should be considered in fertilization management and environmental risk analysis, and the effects of soil parent material should also be taken into account in the application of phosphate fertilizer.


Assuntos
Fertilizantes , Fósforo , Agricultura , China , Fertilizantes/análise , Nitrogênio/análise , Fósforo/análise , Solo
15.
Clin Cancer Res ; 27(18): 5028-5037, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34210683

RESUMO

PURPOSE: M-protein is a well-established biomarker used for multiple myeloma monitoring. Current improvements in multiple myeloma treatment created the need to monitor minimal residual disease (MRD) with high sensitivity. Measuring residual levels of M-protein in serum by MS was established as a sensitive assay for disease monitoring. In this study we evaluated the performance of EasyM-a noninvasive, sensitive, MS-based assay for M-protein monitoring. EXPERIMENTAL DESIGN: Twenty-six patients enrolled in MCRN-001 clinical trial of two high-dose alkylating agents as conditioning followed by lenalidomide maintenance were selected for the study. All selected patients achieved complete responses (CR) during treatment, whereas five experienced progressive disease on study. The M-protein of each patient was first sequenced from the diagnostic serum using our de novo protein sequencing platform. The patient-specific M-protein peptides were then measured by targeted MS assay to monitor the response to treatment. RESULTS: The M-protein doubling over 6 months measured by EasyM could predict the relapse in 4 of 5 relapsed patients 2 to 11 months earlier than conventional testing. In 21 disease-free patients, the M-protein was still detectable by EasyM despite normal FLC and MRD negativity. Importantly, of 72 MRD negative samples with CR status, 62 were positive by EasyM. The best sensitivity achieved by EasyM, detecting 0.58 mg/L of M-protein, was 1,000- and 200-fold higher compared with serum protein electrophoresis and immunofixation electrophoresis, respectively. CONCLUSIONS: EasyM was demonstrated to be a noninvasive, sensitive assay with superior performance compared with other assays, making it ideal for multiple myeloma monitoring and relapse prediction.


Assuntos
Mieloma Múltiplo , Humanos , Lenalidomida , Espectrometria de Massas , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasia Residual
16.
J Proteome Res ; 20(8): 4176-4185, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34242034

RESUMO

The amino acid sequence of the M-protein for multiple myeloma is unique compared to the polyclonal antibodies in patients' blood. This uniqueness is exploited to develop an ultrasensitive M-protein detection method utilizing mass spectrometry (MS). The method involves the de novo amino acid sequencing of the full-length M-protein, and a targeted MS/MS assay to detect and quantify the unique M-protein sequence in serum samples. Healthy control serum spiked with NISTmAb and serial samples from an MM patient were used to demonstrate the ability of the platform to sequence and monitor a target M-protein. The de novo NISTmAb protein sequence obtained matched the published sequence, confirming the ability of the platform to accurately sequence a target M-protein in serum. NISTmAb was quantified down to 0.0002 g/dL in serum, a level hundreds of times more sensitive than conventional blood-based tests such as SPEP and IFE. The M-protein in the patient sample could be quantified throughout complete remission, demonstrating the utility of the assay to track M-protein considerably beyond the sensitivities of current blood-based tests. Notably, the assay detected a 2-fold rise in M-protein levels 10 months before any changes were detected by conventional IFE. The MS-based assay is highly sensitive, noninvasive, and requires only a small amount of serum, less than 100 µL. Sequencing data is deposited into PRIDE with identifier PXD022784, and quantification data can be found in Panorama Public with identifier PXD022980.


Assuntos
Mieloma Múltiplo , Sequência de Aminoácidos , Humanos , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/genética , Espectrometria de Massas em Tandem
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120002, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34090095

RESUMO

The utilization and residue of pesticides exist multifaceted non-restrictive effects on food safety and ecological protection. Exploitation of rapid and sensitive pesticide detection technology is imperative and will be helpful to better control the detriment of pesticides. Here, a novel flexible film has been prepared based on organic-inorganic composite materials (coumarin-3-carboxylic acid and GdF3:Sm3+), which exhibits good optical performance and can well realize the timely and maneuverable detection for different pesticides. The spectra and luminescence properties of each composition in the composite have been analyzed systematically, and the coordinated fluorescence emission of Sm3+ and coumarin-3-carboxylic acid is revealed at an excitation wavelength of 373 nm. Besides, the energy transfer mechanism is also researched by both experiment and theoretical calculation. The actual detection of different pesticides reveals differential fluorescence influence degree. Meanwhile, the flexible film still possesses sensitive recognition in the presence of micro concentration of pesticides. Results indicate that the flexible film with good optical performance can produce visual detection ability and provide a promising strategy for wider detection applications.


Assuntos
Praguicidas , Cumarínicos , Luminescência , Praguicidas/análise , Espectrometria de Fluorescência
18.
Water Res ; 198: 117122, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33865027

RESUMO

Methane is a type of renewable fuel that can generate many types of high value-added chemicals, however, besides heat and power production, there is little methane utilization in most of the wastewater treatment plants (WWTPs) all round the world currently. In this review, the status of methane production performance from WWTPs was firstly investigated. Subsequently, based on the identification and classification of methane oxidizing bacteria (MOB), the key enzymes and metabolic pathway of MOB were presented in depth. Then the production, extraction and purification process of high value-added chemicals, including methanol, ectoine, biofuel, bioplastic, methane protein and extracellular polysaccharides, were introduced in detail, which was conducive to understand the bioconversion process of methane. Finally, the use of methane in wastewater treatment process, including nitrogen removal, emerging contaminants removal as well as resource recovery was extensively explored. These findings could provide guidance in the development of sustainable economy and environment, and facilitate biological methane conversion by using MOB in further attempts.


Assuntos
Methylococcaceae , Purificação da Água , Biocombustíveis , Estudos de Viabilidade , Metano
19.
Nano Lett ; 21(9): 3981-3988, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33886344

RESUMO

The recent proposal of antidoping scheme breaks new ground in conceiving conversely functional materials and devices; yet, the few available examples belong to the correlated electron systems. Here, we demonstrate both theoretically and experimentally that the main group oxide BaBiO3 is a model system for antidoping using oxygen vacancies. The first-principles calculations show that the band gap systematically increases due to the strongly enhanced Bi-O breathing distortions away from the vacancies and the annihilation of Bi 6s/O 2p hybridized conduction bands near the vacancies. Our further spectroscopic experiments confirm that the band gap increases systematically with electron doping, with a maximal gap enhancement of ∼75% when the film's stoichiometry is reduced to BaBiO2.75. These results unambiguously demonstrate the remarkable antidoping effect in a material without strong electron correlations and underscores the importance of bond disproportionation in realizing such an effect.

20.
Injury ; 52(11): 3478-3482, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33487408

RESUMO

BACKGROUND: Postoperative malalignment in fractures treated by monolateral external fixation is not uncommon in clinical practice. Accurate reduction without excessive tissue disruption caused by surgical intervention and sequentially manage the fractures using monolateral external fixation for definitive treatment is still a challenge for surgeons. The purpose of our study was to evaluate the feasibility and effectiveness of the temporary application of the hexapod external fixator (HEF) for the postoperative malalignment correction in tibial diaphyseal fractures treated by monolateral external fixation. METHODS: We carried out a retrospective analysis of 23 trauma patients with tibial diaphyseal fracture treated by the monolateral external fixation at our institution from January 2016 to May 2019. There were 21 males and 2 females with a mean age of 38 years (range 18-60 years). The hexapod external fixator was temporarily applied due to postoperative malalignment within two weeks and who unwilling to undergo a secondary surgical intervention. For patients with postoperative malalignment requiring correction, the HEF components were installed on the original existing half pins of the monolateral external fixator after removing the connecting rod. The standard anteroposterior and lateral X-rays of the injured limb combined with the temporary HEF were conducted to measure the hexapod external fixator parameters. Any residual deformities were corrected by gradual struts adjustment with the aid of computer-based software. When satisfactory alignment was achieved, the HEF was removed, and the monolateral external fixator was sequentially used as the definitive structure. RESULTS: All patients acquired functional reduction, which was evaluated by radiographs. The mean correction time was 4 days (range 2 to 8 days). The mean coronal plane translation (1.3±1.0 mm), coronal plane angulation (0.9±0.7°), sagittal plane translation (1.4±1.1 mm), and sagittal plane angulation (0.7±0.7°) after correction were all less than those (7.0±4.9 mm, 4.7±2.3°, 5.6±3.6 mm, 3.2±2.5°) before correction. CONCLUSIONS: The temporary application of the hexapod external fixator is an alternative and feasible method for the postoperative malalignment correction in tibial diaphyseal fractures treated by monolateral external fixation.


Assuntos
Fixadores Externos , Fraturas da Tíbia , Adolescente , Adulto , Diáfises/diagnóstico por imagem , Diáfises/cirurgia , Feminino , Fixação de Fratura , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/cirurgia , Resultado do Tratamento , Adulto Jovem
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