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1.
Kardiologiia ; 64(4): 54-60, 2024 Apr 30.
Artigo em Russo, Inglês | MEDLINE | ID: mdl-38742516

RESUMO

AIM: To estimate the prevalence of amyloid cardiomyopathy (CM) caused by transthyretin amyloidosis (ATTR) and immunoglobulin light chain (AL) amyloidosis among patients aged >65 years with interventricular septal (IVS) hypertrophy of ≥14 mm. MATERIAL AND METHODS: From January through August 2023, 60 patients (mean age 7.2±7.3 years, 34 (56.67%) men) were enrolled. Patients meeting the inclusion criteria underwent an echocardiographic study with determining the myocardial longitudinal strain, myocardial scintigraphy with 99mTc-pyrfotech, myocardial single-photon emission computed tomography, measurement of N-terminal fragment of brain natriuretic peptide and troponin I, and the immunochemical study of serum and urine proteins with measurement of free light chains. In the presence of grades 2 and 3 radiopharmaceutical uptake according to scintigraphy, a molecular genetic study was performed for differential diagnosis of wild-type transthyretin amyloidosis (wtATTR) and hereditary/variant (hATTR) ATTR-CM. RESULTS: According to data of myocardial scintigraphy with 99mTc-pyrfotech, grade 3 uptake in the absence of monoclonal secretion was detected in 5 (8.3%) cases and grade 2 radiotracer uptake in the absence of monoclonal secretion was detected in 6 (10%) patients. Myeloma complicated by AL amyloidosis and primary AL amyloidosis were found in 5 (8.3%) patients. CONCLUSION: Among patients aged ≥65 years with IVS hypertrophy ≥14 mm, amyloid CM was detected in 20% of cases (12 patients), including 5 cases (8.3%) of AL amyloidosis and 7 cases (11.7%) of ATTR amyloidosis.


Assuntos
Neuropatias Amiloides Familiares , Cardiomiopatias , Hipertrofia Ventricular Esquerda , Idoso , Feminino , Humanos , Masculino , Neuropatias Amiloides Familiares/epidemiologia , Neuropatias Amiloides Familiares/complicações , Neuropatias Amiloides Familiares/diagnóstico , Cardiomiopatias/epidemiologia , Ecocardiografia , Hipertrofia Ventricular Esquerda/epidemiologia , Amiloidose de Cadeia Leve de Imunoglobulina/epidemiologia , Amiloidose de Cadeia Leve de Imunoglobulina/complicações , Prevalência , Federação Russa/epidemiologia , Tomografia Computadorizada de Emissão de Fóton Único
2.
Environ Monit Assess ; 196(5): 444, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607455

RESUMO

This study aimed to monitor long-term land use dynamics for understanding the natural forest integrity and intactness of the Rajiv Gandhi (Nagarhole) Tiger Reserve (RTR) pre- and post-declarations as TR. We employed multi-source data from Survey of India Toposheets (1:50 k), Landsat-7, and Sentinel-2A along with Global Ecosystem Dynamics Investigation (GEDI) vegetation canopy height (10 m) data, a high-spatial resolution CORONA (1970) images and temporal Google Earth Pro images for mapping and validation. To map vegetation type, land use and land cover (LULC) transitions, and fragmentation (1980-2022) we employed a hybrid classification approach. This study also analyzed decadal forest dynamics within TRs using India's State of Forest Reports (ISFR). Findings reveal significant forest fragmentation and habitat loss due to anthropogenic activities in the TR. Mono-plantations (teak and eucalyptus) were found inside TR, while the buffer (1 km) was occupied mainly with coffee and orange plantations which indicates the prevalence of human footprint. The overall accuracy of the current period (2022) is 92.0% with a kappa coefficient value of 0.90. These plantations were established during the British colonial period (early 1900s) for commercial purposes by clearing natural forests. The present study highlights that mono-plantations have not transitioned into natural forests even after a century. This lack of transformation could potentially compromise the integrity of the native forest. Despite its ecological significance, RTR has experienced disturbance due to human footprint. Hence, there is a need for an action plan to protect this vital landscape by replacing mono-plantations with suitable species to preserve the integrity of the forest. These issues extend beyond the protected areas, impacting surrounding regions and require regular monitoring. The proposed methods can be applied to other protected areas facing similar problems in the country and world.


Assuntos
Ecossistema , Monitoramento Ambiental , Humanos , Efeitos Antropogênicos , Café , Florestas
3.
Cureus ; 16(2): e54243, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38496188

RESUMO

Background Pesticides, including insecticides, herbicides, and fungicides, are essential for global food production, boosting crop yields, and preventing disease transmission. However, their excessive and improper use raises concerns about potential long-term consequences, affecting microbial ecosystems and fostering antimicrobial resistance. Materials and methods The objective of the study was to identify the effect of the pesticide compound (Imidacloprid 17.1% w/w) on the ATCC Escherichia coli. An experiment was conducted on ATCC Escherichia coli 27852. A 0.5 McFarland suspension of the strain was incubated in the presence of a pesticide compound (Imidacloprid 17.1% w/w) at a dilution of 1:4, 1:8, and 1:16. at 370C. Antibiotic susceptibility for cefoxitin, ciprofloxacin, ceftazidime, amikacin, and imipenem was determined via the Kirby-Bauer disk diffusion test at intervals of 24 hours, 48 hours, seven days, and 21 days. The results were then compared to the standard zone of inhibition diameter for ATCC Escherichia coli 27852 by Clinical and Laboratory Standards Institute (CLSI) guidelines. Results No bacterial growth was detected at pesticide dilutions of 1:1 and 1:2, indicating their inability to tolerate high pesticide concentrations. However, growth became evident at a 1:4 dilution and beyond, with mutants thriving within the inhibition zone. The experiment caused significant alterations in the inhibition zone sizes for all antibiotics, especially notable with imipenem, amikacin, and ceftazidime compared to the initial zone size for ATCC Escherichia coli 27852. Conclusion Our study concludes that the pesticide (Imidacloprid 17.1% w/w) significantly influences antibiotic resistance, especially with carbapenems, aminoglycosides, and cephalosporins in the tested groups at various concentrations and durations of exposure.

4.
RSC Adv ; 14(8): 5022-5036, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38332782

RESUMO

Polyvinyl alcohol/yttrium oxide (PVA/Y2O3) nanocomposite films with five different weight ratios of PVA and Y2O3 nanoparticles (NPs) were prepared using a simple solution casting method. The prepared polymer nanocomposite (PNC) films were examined using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). FTIR spectra exhibited a strong interaction between the PVA matrix and Y2O3 NPs. SEM results indicated that Y2O3 NPs were properly dispersed in the PVA matrix. The thermal stability of the PVA/Y2O3 nanocomposite films was found to be dependent on Y2O3 NP loading (wt%) in the nanocomposite films. Furthermore, chemiresistive gas sensing properties of the PVA/Y2O3 nanocomposite films were evaluated and the sensing parameters including sensing response, operating temperature, selectivity, stability, response/recovery time, and repeatability were systematically investigated based on the change in electrical resistance of the nanocomposite film in the presence of carbon dioxide (CO2) gas. The maximum sensing response (S) of 92.72% at a concentration of 100 ppm under an optimized operating temperature of 100 °C with a fast response/recovery time of ∼15/11 s towards CO2 gas detection was observed for the PVA/Y2O3 nanocomposite film with 5 wt% loading of Y2O3 NPs in the PVA matrix. The finding in this work suggest that Y2O3 NPs are sufficiently fast as a CO2 gas sensing material at a relatively low operating temperature. Moreover, the key role of the Y2O3 NPs in modulating the electrical and gas sensing properties of the PVA matrix is discussed here.

5.
Environ Monit Assess ; 196(2): 196, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38265744

RESUMO

Climate change is one of the factors contributing to the spread of invasive alien species. As a result, it is critical to investigate potential invasion dynamics on a global scale in the face of climate change. We used updated occurrence data, bioclimatic variables, and Köppen-Geiger climatic zones to better understand the climatic niche dynamics of Prosopis juliflora L. (Fabaceae). In this study, we first compared several algorithms-MaxEnt, generalized linear model (GLM), artificial neural network (ANN), generalized boosted model (GBM), generalized additive model (GAM), and random forest (RF)-to investigate the relationships between species-environment and climate for mesquite. We identified the global climate niche similarity sites (NSSs) using the coalesce approach. This study focused on the current and future climatic suitability of P. juliflora under two global circulation models (GCMs) and two climatic scenarios, i.e., Representative Concentration Pathways (RCPs), 4.5 and 8.5, for 2050 and 2070, respectively. Sensitivity, specificity, true skill statistic (TSS), kappa coefficient, and correlation were used to evaluate model performance. Among the tested models, the machine learning algorithm random forest (RF) demonstrated the highest accuracy. The vast swaths of currently uninvaded land on multiple continents are ideal habitats for invasion. Approximately 9.65% of the area is highly suitable for the establishment of P. juliflora. Consequently, certain regions in the Americas, Africa, Asia, Europe, and Oceania have become particularly vulnerable to invasion. In relation to RCPs, we identified suitable area changes (expansion, loss, and stability). The findings of this study show that NSSs and RCPs increase the risk of invasion in specific parts of the world. Our findings contribute to a cross-border continental conservation effort to combat P. juliflora  expansion into new potential invasion areas.


Assuntos
Prosopis , Espécies Introduzidas , Monitoramento Ambiental , Mudança Climática , Aprendizado de Máquina
6.
BMC Nutr ; 9(1): 125, 2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37925425

RESUMO

BACKGROUND: By 2050, approximately 68% of the global population will live in cities, but nutrition data on urban populations of low- and middle-income countries are scarce. Fast growing secondary cities, combining characteristics and hurdles of urban and rural settings, are hotspots for the double burden of malnutrition. The Nutrition in City Ecosystems (NICE) project focuses on 6 secondary cities in Bangladesh, Kenya and Rwanda, to improve health and nutrition, and reduce poverty. To assess the baseline situation and guide future interventions, food insecurity, dietary diversity, nutrition status, and food production and purchasing patterns were explored. METHODS: In a cross-sectional study design, data were collected from urban and peri-urban households of Dinajpur and Rangpur in Bangladesh, Bungoma and Busia in Kenya, and Rubavu and Rusizi in Rwanda. Approximately 1200 households, in neighborhoods prone to malnutrition, were involved from April to June 2021. We assessed Household Food Insecurity Access Score (HFIAS), both current and before COVID-19, Household Dietary Diversity Score (HDDS), Minimum Dietary Diversity for Women (MDD-W), anthropometric measurements, household and socioeconomic information, and questions related to food production and consumer behavior. Further we collected secondary data on low birthweight and anemia during pregnancy. RESULTS: All cities experienced a substantial increase in food insecurity during the COVID-19 pandemic. Stunting rates in children under 5 years varied among the cities and ranged from 7.8% in Busia to 46.6% in Rubavu, while half of adult women were overweight (between 42.1% in Rusizi and 55.8% in Bungoma). Furthermore, many women did not consume an adequately diverse diet (MDD-W < 5 for 29.3% in Bangladesh, 47.5% in Kenya, and 67.0% in Rwanda), however many of the urban and peri-urban households were engaged in farming (58-78%). CONCLUSIONS: The double burden of malnutrition is high in secondary cities and the COVID-19 pandemic has exacerbated levels of food insecurity. Demand for, and access to, an affordable healthy diverse diet that comprises local, nutritious, and agroecologically produced foods present a pathway for overcoming the complex challenges of malnutrition.

7.
Cureus ; 15(8): e43895, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37746408

RESUMO

Background Ventilator-associated pneumonia (VAP) is defined as pneumonia that develops 48 hours or more after endotracheal intubation or tracheostomy and is brought on by infectious organisms that are not present or incubating during mechanical ventilation. Multidrug-resistant organisms originate primarily from the hospital environment and significantly contribute to ventilator-associated pneumonia. These organisms pose a severe threat, leading to a higher mortality rate due to their resistance to more potent antibiotics. Methods The study aims to assess the efficacy of the modified Carba NP test in detecting carbapenemase-producing bacteria in geriatric VAP patients. Results Forty (38 gram-negative and 2 gram-positive) pathogens were isolated from VAP patients. The isolates were identified using standard laboratory protocol; Acinetobacter spp. (n=16; 40% ), followed by Klebsiella pneumoniae (n=13; 32.5%), is the most common organism isolated. Seventeen (44.73%) were multi-drug resistant gram-negative bacteria. The carbapenemase producers were detected by the Kirby-Bauer disc diffusion method and compared with the modified Carba NP test with a turnaround time of 12-18 hrs in comparison to the disk diffusion test which requires additional 12hrs. Carbapenemase production was seen in 12 (70.59%) MDR isolates (7-Acinetobacter spp, 3-Klebsiella pneumonia, 1-Escherichia coli, and 1-Pseudomonas aeruginosa).  Conclusion Modified Carba NP can be used as a rapid test to detect carbapenemase production, and it can replace the traditional disk diffusion method of detecting carbapenemase production. This test plays a crucial role in the management of critical patients by saving 12-18 hours to determine the most appropriate and effective antibiotic treatment. This timely decision is essential in preventing sepsis caused by localized infections.

8.
Langmuir ; 39(37): 13345-13358, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37679052

RESUMO

A simple solution casting technique was used to fabricate perovskite strontium titanate (SrTiO3)-loaded poly(vinylidenefluoride-co-hexafluoropropylene) (PVDF-HFP) nanocomposite films for efficient energy storage applications. Various microscopic and spectroscopic methods were used to study the characteristics of the polymer nanocomposite films, like Fourier transform infrared spectroscopy (FTIR), X-ray diffraction technique (XRD), field emission scanning electron microscopy (FESEM), ultraviolet-visible spectroscopy, thermogravimetric analysis, and mechanical tensile test (stress vs strain). The FTIR, XRD, and FESEM analyses confirmed the incorporation and proper dispersion of SrTiO3 nanoparticles in the PVDF-HFP polymer matrix. An improvement in the optical, thermal, and mechanical behavior of the nanocomposite film was observed compared to the pure polymer. The values of dielectric constant, loss tangent, and AC conductivity of pure PVDF-HFP polymer and PVDF-HFP/SrTiO3 nanocomposites (2, 6, and 10 wt % SrTiO3 loadings) were analyzed in a temperature and frequency span of 30-150 °C and 1-100 kHz, respectively. To better understand the electrical properties of the materials, Nyquist plots were generated, and their related circuit designs were fitted. The 2 wt % SrTiO3 loaded nanocomposite exhibited the highest dielectric enhancement and AC conductivity compared to higher filler-loaded nanocomposites. This exceptional dielectric enhancement at very small filler loading is beneficial for commercialization and economically viable for real-time applications.

9.
Environ Monit Assess ; 195(2): 348, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36719637

RESUMO

The present study focuses on the spread of rubber monoculture in the state of Tripura during past three decades (1990-2021) in the northeast region of India which is known for its rich biodiversity, shifting cultivation, and extensive forest dynamics. Earth observation (EO) data of seven time periods from Landsat missions (1990, 1995, 2000, 2004, and 2009) and Sentinel-2 (2016 and 2021) were the main source for mapping and were supplemented with MODIS-EVI temporal spectral profiles, GEDI-derived vegetation heights (2019), and Google Earth high-resolution historical images for additional cues to support discrimination, mapping, and accuracy assessment. The methodology for rubber used its unique phenology from spectral-temporal profile and multi-year comparison of patches and their dynamics for age-class mapping. The results indicate that in the state of Tripura (geographic area 1.08 Mha), the area under rubber increased from 0.3% in 1990 to 8.9% of the geographic area in 2021. The overall classification accuracy for the maps created for the years 1990, 1995, 2000, 2004, 2009, 2016, and 2021 was 84.2%, 83.9%, 84.8%, 88.0%, 86.0%, 86.7%, and 89.5%, respectively. New areas under rubber originated from various land cover classes including open forests, shifting cultivation lands, and scrub. Recent expansion has resulted in 84.3% of rubber plantations under the 10-year age class. Implications of this transformation of the natural landscape, biodiversity and biomass, and carbon pool assessment are discussed.


Assuntos
Monitoramento Ambiental , Borracha , Monitoramento Ambiental/métodos , Florestas , Biodiversidade , Índia
10.
Light Sci Appl ; 11(1): 250, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35945216

RESUMO

The global energy crisis is increasing the demand for innovative materials with high purity and functionality for the development of clean energy production and storage. The development of novel photo- and electrocatalysts significantly depends on synthetic techniques that facilitate the production of tailored advanced nanomaterials. The emerging use of pulsed laser in liquid synthesis has attracted immense interest as an effective synthetic technology with several advantages over conventional chemical and physical synthetic routes, including the fine-tuning of size, composition, surface, and crystalline structures, and defect densities and is associated with the catalytic, electronic, thermal, optical, and mechanical properties of the produced nanomaterials. Herein, we present an overview of the fundamental understanding and importance of the pulsed laser process, namely various roles and mechanisms involved in the production of various types of nanomaterials, such as metal nanoparticles, oxides, non-oxides, and carbon-based materials. We mainly cover the advancement of photo- and electrocatalytic nanomaterials via pulsed laser-assisted technologies with detailed mechanistic insights and structural optimization along with effective catalytic performances in various energy and environmental remediation processes. Finally, the future directions and challenges of pulsed laser techniques are briefly underlined. This review can exert practical guidance for the future design and fabrication of innovative pulsed laser-induced nanomaterials with fascinating properties for advanced catalysis applications.

11.
Qatar Med J ; 2022(3): 40, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35974885

RESUMO

Healthcare professionals monitoring vaccine-related adverse responses should be aware of COVID-19 vaccine-related acute respiratory distress syndrome to enable expeditious diagnosis and treatment. We report the first case of acute respiratory distress syndrome in a young pregnant woman, occurring immediately after a second dose of the Pfizer-BioNTech BNT16B2b2 mRNA COVID-19 vaccine and requiring a brief period of mechanical ventilation, with a good response to a two-week steroid course. She had recovered from mild COVID-19 infection requiring home isolation nine months prior to the current vaccination dose. Without depreciating the colossal benefit of the COVID-19 vaccine, vaccine-related acute respiratory distress syndrome should be listed as a possible adverse reaction.

12.
Environ Res ; 204(Pt D): 112359, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34774834

RESUMO

Removing decolorizing acid blue 113 (AB113) dye from textile wastewater is challenging due to its high stability and resistance to removal. In this study, we used an artificial neural network (ANN) model to estimate the effect of five different variables on AB113 dye removal in the sonophotocatalytic process. The five variables considered were reaction time (5-25 min), pH (3-11), ZnO dosage (0.2-1.0 g/L), ultrasonic power (100-300 W/L), and persulphate dosage (0.2-3 mmol/L). The most effective model had a 5-7-1 architecture, with an average deviation of 0.44 and R2 of 0.99. A sensitivity analysis was used to analyze the impact of different process variables on removal efficiency and to identify the most effective variable settings for maximum dye removal. Then, an imaginary sonophotocatalytic system was created to measure the quantitative impact of other process parameters on AB113 dye removal. The optimum process parameters for maximum AB 113 removal were identified as 6.2 pH, 25 min reaction time, 300 W/L ultrasonic power, 1.0 g/L ZnO dosage, and 2.54 mmol/L persulfate dosage. The model created was able to identify trends in dye removal and can contribute to future experiments.


Assuntos
Compostos Azo , Redes Neurais de Computação , Têxteis , Águas Residuárias
13.
Environ Res ; 204(Pt C): 112297, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34740623

RESUMO

PVDF-HFP/BaTiO3/GQDs polymer nanocomposite films with good flexibility and high dielectric constant (ϵ) at low frequency were prepared via solution casting technique. Different compositions of BaTiO3 (non-conducting ceramic nanofiller) and Graphene quantum dots (GQDs) (conducting nanofiller) utilized as co-filler were embedded in poly (vinylidene fluoride-co-hexafluoroethylene) (PVDF-HFP) polymer matrix. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and Scanning electron microscopy (SEM) techniques were employed to characterize the prepared nanocomposite films. The mechanical properties of PVDF-HFP/BaTiO3/GQDs nanocomposite films were also investigated. Dielectric properties of nanocomposite films such as dielectric constant (ϵ), dielectric loss (tanδ) and AC conductivity ( σac ) were also determined as a function of frequency and temperature. Highest ϵ with relatively low tanδ obtained at low frequency for maximum temperature in all polymer nanocomposite films. The σac increases from lower (100 Hz) to higher frequency up to 100 kHz and drops to zero for the further increment of frequency. These results suggest that the PVDF-HFP/BaTiO3/GQDs nanocomposites are the most promising materials for energy storage applications.


Assuntos
Grafite , Nanocompostos , Nanopartículas , Pontos Quânticos , Bário , Grafite/química , Nanocompostos/química , Pontos Quânticos/química
14.
Environ Res ; 203: 111842, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34363804

RESUMO

Nickel oxide (NiO) nanoparticles (NPs) and graphene quantum dots (GQDs) reinforced polyvinyl alcohol (PVA) nanocomposite films were prepared using a solution casting technique. The physicochemical characteristics of PVA/NiO/GQDs (PNG) nanocomposite films were studied using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM). The obtained PNG nanocomposite films showed good mechanical flexibility and improved tensile strength. The influence of nanofiller concentrations on PNG nanocomposite film. The obtained results demonstrate an increase in the activation energy (Ea) up to PNG3 upon increasing the GQDs concentration and thereafter, its decreases. The fundamental interactions of the constituents of PNG nanocomposite film were investigated using density functional theory (DFT). This study on electronic structure reveals that the PVA model indirectly interacts with GQDs through the NiO model. This configuration is favoured in terms of interaction energy (-78 kJ/mol) compared to the one in which PVA interacts directly with the GQDs model.


Assuntos
Grafite , Nanocompostos , Nanopartículas , Pontos Quânticos , Níquel , Álcool de Polivinil , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Chemosphere ; 277: 130237, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34384171

RESUMO

In the present work, the cost effective and facile hydrothermal synthesis technique was adopted to synthesize the copper (׀׀) oxide (CuO)-Nanoparticles (NPs). Physico-chemical characterization of the synthesized CuO-NPs was done by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Ultraviolet-visible spectroscopy (UV-Vis), and scanning electron microscopy (SEM) analysis were carried out to study the structural, optical, and surface morphology of nanomaterial. XRD analysis revealed that the synthesized CuO-NPs had monoclinic structure and the average crystallite size is 20 nm. FTIR spectra indicate the vibrational bands of metal oxygen bonds (Cu-O). UV-visible absorption spectra were utilized to determine the energy band gap (Eg) of the CuO-NPs. In addition, we fabricated the chemiresistive sensor using synthesized CuO-NPs for detecting Volatile Organic Compounds (VOCs). These results demonstrate that CuO-NPs based chemiresistive sensor is ideal for qualitative detection of BTEX chemicals vapors (i.e. Benzene, Toluene, Ethylbenzene, and Xylene).


Assuntos
Cobre , Nanopartículas , Óxidos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
16.
Environ Res ; 201: 111429, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34146527

RESUMO

Effective improvement of an easily recoverable photocatalyst is equally vital to its photocatalytic performance from a practical application view. The magnetically recoverable process is one of the easiest ways, provided the photocatalyst is magnetically strong enough to respond to an external magnetic field. Herein, we prepared graphitic carbon nitride nanosheet (g-C3N4), and ZnS quantum dots (QDs) supported ferromagnetic CoFe2O4 nanoparticles (NPs) as the gC3N4/ZnS/CoFe2O4 nanohybrid photocatalyst by a wet-impregnation method. The loading of CoFe2O4 NPs in the g-C3N4/ZnS nanohybrid resulted in extended visible light absorption. The ferromagnetic g-C3N4/ZnS/CoFe2O4 nanohybrid exhibited better visible-light-active photocatalytic performance (97.11%) against methylene blue (MB) dye, and it was easily separable from the aqueous solution by an external bar magnet. The g-C3N4/ZnS/CoFe2O4 nanohybrid displayed excellent photostability and reusability after five consecutive cycles. The favourable band alignment and availability of a large number of active sites affected the better charge separation and enhanced photocatalytic response. The role of active species involved in the degradation of MB dye during photocatalyst by g-C3N4/ZnS/CoFe2O4 nanohybrid was also investigated. Overall, this study provides a facile method for design eco-friendly and promising g-C3N4/ZnS/CoFe2O4 nanohybrid photocatalyst as applicable in the eco-friendly dye degradation process.


Assuntos
Iluminação , Nanocompostos , Catálise , Luz , Fotólise , Sulfetos , Compostos de Zinco
17.
Stud Health Technol Inform ; 280: 9-13, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34190052

RESUMO

The etiology of the adolescent idiopathic scoliosis (AIS) remains unknown. Variations in the sagittal profile of the spine between the early stage scoliotic and non-scoliotic pediatric patients have been shown. However, no quantitative study has shown the link between the sagittal profile and 3D deformity of the spine. 126 right thoracic scoliosis with spinal and 3D reconstructions were included. A 2D finite element model was developed for each of the sagittal curve types without any deformity in the frontal or axial planes. Physiological loadings were determined from the literature and were applied in the finite element model. The 3D deformation patterns of the models were compared to the 3D spinal patterns of the AIS with the same sagittal type. A significant correlation was found between the 3D deformity of the scoliotic curves and the numerical finite element simulation of the corresponding sagittal profile as determined by pattern correlation, p<0.001. The sagittal curve deformation patterns corresponded to the spinal deformities in the patients with the same sagittal curvature. Finite element models of the spines, representing different sagittal types in 126 AIS patients showed that deformation pattern of the sagittal types changes as a function of the spine curvature and associates with the patterns of 3D spinal deformity in AIS patients with the same sagittal curves. This finding provided evidence that the sagittal curve of the spine can determine the deformity patterns in AIS.


Assuntos
Cifose , Escoliose , Curvaturas da Coluna Vertebral , Adolescente , Criança , Simulação por Computador , Humanos , Estudos Retrospectivos , Escoliose/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas
18.
Stud Health Technol Inform ; 280: 18-22, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34190054

RESUMO

Idiopathic scoliosis in man is believed to be related to the unique human sagittal profile. Patients with a thoracic scoliosis have a longer, more proximal, posteriorly inclined segment of the spine as compared to lumbar scoliosis and controls, whereas patients with a lumbar scoliosis have a more caudal, shorter and steeper posteriorly inclined segment. In 22q11.2 deletion syndrome, half of the patients develop a scoliosis that is very similar to idiopathic scoliosis and may serve as a model for the general population. In our center, all patients with 22q11.2 deletion syndrome older than 6 years receive standardized radiographic spine imaging every 2 years to screen for scoliosis. In this prospective proof-of-principle study the goal was to determine whether there are differences in sagittal alignment between patients that develop scoliosis vs. controls before the onset of scoliosis, and obtain data to perform a power calculation for future studies. To capture the sagittal shape of the spine into one risk factor for development for scoliosis, we combined relative length and magnitude of dorsal inclination into a new parameter: the posterior inclined triangle surface (PITS). We included 31 patients with initially straight spines, five developed a thoracic scoliosis and seven developed a (thoraco)lumbar scoliosis after a mean follow-up of 3.4 years. The PITS was considerably higher in the group that developed scoliosis as compared to the controls (59 vs 43). Based on this pilot study, we have identified a potential overall sagittal profile risk parameter for the development of idiopathic scoliosis.


Assuntos
Cifose , Escoliose , Humanos , Cifose/diagnóstico por imagem , Vértebras Lombares , Projetos Piloto , Estudos Prospectivos , Radiografia , Estudos Retrospectivos , Escoliose/diagnóstico por imagem
19.
Stud Health Technol Inform ; 280: 53-57, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34190060

RESUMO

The pathomechanism of spinal deformity development in adolescent idiopathic scoliosis (AIS) has been related to the sagittal curvature of the spine. It is not known how the variations in the sagittal profile relates to the coronal deformity patterns in AIS. A total of 70 Lenke 1 and 50 Lenke 5 AIS patients were included retrospectively. A finite element (FE) model was developed for each spine where the sagittal spinal curvatures were modeled as 2D S shaped elastic rods. Transverse plane deformation patterns of these rods under physiological loading were determined and clustered based on their similarities. The patients' characteristics, including the Lenke type, and the spinal measurements in these deformation pattern clusters were statistically compared. Three different axial deformation patterns were determined from the FE simulations of the 120 sagittal curves. Two axial groups were looped shaped in opposing directions (Group I and III) and one was lemniscate shaped (Group II). 94% of the patients in Groups I and II were Lenke 1 and 100% of Group III was Lenke 5. The position of the sagittal inflection point moved downward from Group I-III resulting in significantly different ratio of the arc lengths above and below the sagittal inflection points for Groups I, II and III (0.49±0.59, 1.15±0.44, and 3.22±1.8). A classification of idiopathic scoliosis, based on the biomechanics of S-shaped flexible rods deformation could distinguish between different coronal curve types. The geometrical parameters of the sagittal profiles in the axial deformation pattern groups were significantly different.


Assuntos
Escoliose , Vértebras Torácicas , Adolescente , Humanos , Vértebras Lombares , Radiografia , Estudos Retrospectivos , Escoliose/diagnóstico por imagem
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