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1.
Clin Transplant ; 35(6): e14316, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33844367

RESUMO

Deceased organ donor intervention research aims to increase organ quality and quantity for transplantation. We assessed the proportion of kidney transplant candidates who would accept "intervention organs," participate in organ intervention research, and factors influencing acceptance. Kidney transplant candidates were presented 12 hypothetical scenarios, which varied three attributes, donor age, predicted waiting time to receive another organ offer, and research risk to the organ. Candidates were also randomly assigned to one of two conditions varying recipient risk. For each scenario, candidates agreed to accept the intervention organ or remain waitlisted. We fit a multivariable logit model to determine the association between scenario attributes and the acceptance decision. Of 249 participants, most (96%) accepted intervention organs under some or all conditions. Factors independently associated with candidates' greater likelihood of accepting an intervention organ included: low risk to the kidney from the intervention (OR 20.53 [95% Confidence Interval (CI), 13.91-30.29]); younger donor age (OR 3.72 [95% CI, 2.83-4.89]), longer time until the next organ offer (OR 3.48 [95% CI, 2.65-4.57]), and greater trust in their transplant physician (OR 1.03 [95% CI, 1.00-1.06]). Candidates with a lower likelihood of acceptance had been waitlisted longer (OR 0.97 per month [95% CI, 0.96-0.99]) and were Black (OR 0.21 [95% CI, 0.08-0.55]). Most candidates would accept an intervention organ, which should encourage transplant leaders to conduct deceased donor organ intervention trials.


Assuntos
Transplante de Rim , Obtenção de Tecidos e Órgãos , Transplantes , Humanos , Doadores de Tecidos , Transplantados , Listas de Espera
2.
Environ Sci Pollut Res Int ; 31(19): 27913-27934, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38523213

RESUMO

Today, new energy sources alternative to fossil fuels are needed to meet the increasing energy demand. It is becoming increasingly important to constitute new energy sources from waste biomass through the liquefaction process. In this study, walnut shells (WS) were liquefied catalytically and non-catalytically under different parameters using the liquefaction method. In this process, the effect of silica fume/nano zero-valent iron (SF/NZVI) catalysts on the conversion rates was investigated. The catalyst was synthesized by reducing NZVI using a liquid phase chemical reduction method on SF. The SF/NZVI catalyst was characterized by scanning electron microscopy- energy dispersive X-ray (SEM-EDX), transmission electron microscope (TEM), Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analysis. The effect of various process parameters on the liquefaction process was investigated. In this context, the reaction temperature ranged from 300 to 400 °C, the solid/solvent ratio ranged from 1/1 to 1/3, the reaction time ranged from 30 to 90 min, and the catalyst concentration ranged from 1 to 6%. According to the results obtained, the most suitable operating conditions for non-catalytic experiments in liquefaction of WS were found to be temperature of 400 °C, reaction time of 60 min, and solid/solvent of 1/3. In catalytic conditions, the optimum values were obtained as temperature of 375 °C, reaction time of 60 min, solid/solvent ratio of 1/3, and catalyst concentration of 6%. The highest total conversion and (oil + gas) % conversion were 90.4% and 46.7% under non-catalytic conditions and 90.7% and 62.3% under catalytic conditions, respectively. Gas chromatography/mass spectrometry (GC/MS) analysis revealed the bio-oil was mainly composed of aromatic compounds (benzene, butyl-, indane and their derivatives,) and polyaromatic compounds (naphthalene, decahydro-, cis-, naphthalene, 1-methyl-.). The aim of increasing the quantity and quality of the light liquid product in the study has been achieved.


Assuntos
Ferro , Óleos de Plantas , Polifenóis , Catálise , Ferro/química , Biocombustíveis , Difração de Raios X , Dióxido de Silício/química , Juglans/química , Biomassa
3.
Light Sci Appl ; 13(1): 43, 2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38310118

RESUMO

Image denoising, one of the essential inverse problems, targets to remove noise/artifacts from input images. In general, digital image denoising algorithms, executed on computers, present latency due to several iterations implemented in, e.g., graphics processing units (GPUs). While deep learning-enabled methods can operate non-iteratively, they also introduce latency and impose a significant computational burden, leading to increased power consumption. Here, we introduce an analog diffractive image denoiser to all-optically and non-iteratively clean various forms of noise and artifacts from input images - implemented at the speed of light propagation within a thin diffractive visual processor that axially spans <250 × λ, where λ is the wavelength of light. This all-optical image denoiser comprises passive transmissive layers optimized using deep learning to physically scatter the optical modes that represent various noise features, causing them to miss the output image Field-of-View (FoV) while retaining the object features of interest. Our results show that these diffractive denoisers can efficiently remove salt and pepper noise and image rendering-related spatial artifacts from input phase or intensity images while achieving an output power efficiency of ~30-40%. We experimentally demonstrated the effectiveness of this analog denoiser architecture using a 3D-printed diffractive visual processor operating at the terahertz spectrum. Owing to their speed, power-efficiency, and minimal computational overhead, all-optical diffractive denoisers can be transformative for various image display and projection systems, including, e.g., holographic displays.

4.
Heliyon ; 8(9): e10636, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36158104

RESUMO

In this study, Yatagan lignite (YL) and peach kernel shells (PKS) were originally taken separately and in a 1: 1 ratio by weight. Experiments were carried out in a 3-zone heated cylindrical furnace in a steel reactor. Structural characterization of all the solid products obtained was made by FTIR, XRD, and SEM analysis. When the FTIR and XRD spectra of the raw samples are examined, it is seen that they are rich in functional groups. It is seen that the PKS has aliphatic and aromatic structures and cellulosic structure -OH stresses (3500 cm-1). The sharp peak around 2918 cm-1 in Yatagan lignite belongs to the aliphatic C-H stretch. In the XRD spectrum, it is seen that both structures are largely amorphous. The raw PKS contains 3 different amorphous macromolecular structures. Yatagan lignite, on the other hand, contains crystalline peaks of clay and inorganic structures, depending on the ash content, as well as the amorphous structure. As the temperature increases depending on the carbonization temperature, as seen in the FTIR spectrum, the peaks of the functional groups decrease and disappear with the disruption of small macromolecular structures. As a result of the structural adjustment with the temperature increase, M-O-M peaks around 1000 cm-1 remain due to the aromatic C-H stretching and ash content. The paper centers around test assurance of operating temperatures in the consuming layer during co-carbonization. It is obtained that 800 °C is the best temperature condition for the co-carbonization process. It has been concluded that the chars obtained as a result of pyrolysis will be used as a solid fuel in both environmental (the lowest sulfur content) and economic (400 °C) sense. However, the fact that it has a very low sulfur content with the increase in the liquid and gas efficiency obtained at high temperatures again proves the production of an environmentally friendly liquid fuel.

5.
J Tissue Eng Regen Med ; 14(12): 1815-1826, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33010108

RESUMO

Regeneration of nerve tissue is a challenging issue in regenerative medicine. Especially, the peripheral nerve defects related to the accidents are one of the leading health problems. For large degeneration of peripheral nerve, nerve grafts are used in order to obtain a connection. These grafts should be biodegradable to prevent second surgical intervention. In order to make more effective nerve tissue engineering materials, nanotechnological improvements were used. Especially, the addition of electrically conductive and biocompatible metallic particles and carbon structures has essential roles in the stimulation of nerves. However, the metabolizing of these structures remains to wonder because of their nondegradable nature. In this study, biodegradable and conductive nerve tissue engineering materials containing zero-valent iron (Fe) nanoparticles were developed and investigated under in vitro conditions. By using electrospinning technique, fibrous mats composed of electrospun poly(ε-caprolactone) (PCL) nanofibers and Fe nanoparticles were obtained. Both electrical conductivity and mechanical properties increased compared with control group that does not contain nanoparticles. Conductivity of PCL/Fe5 and PCL/Fe10 increased to 0.0041 and 0.0152 from 0.0013 Scm-1 , respectively. Cytotoxicity results indicated toxicity for composite mat containing 20% Fe nanoparticles (PCL/Fe20). SH-SY5Y cells were grown on PCL/Fe10 best, which contains 10% Fe nanoparticles. Beta III tubulin staining of dorsal root ganglion neurons seeded on mats revealed higher cell number on PCL/Fe10. This study demonstrated the impact of zero-valent Fe nanoparticles on nerve regeneration. The results showed the efficacy of the conductive nanoparticles, and the amount in the composition has essential roles in the promotion of the neurites.


Assuntos
Ferro/química , Nanopartículas Metálicas/química , Nanofibras/química , Tecido Nervoso/fisiologia , Engenharia Tecidual , Alicerces Teciduais/química , Animais , Astrócitos/citologia , Adesão Celular , Morte Celular , Condutividade Elétrica , Gânglios Espinais/metabolismo , Humanos , Nanopartículas Metálicas/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Células NIH 3T3 , Nanofibras/ultraestrutura , Poliésteres/química , Resistência à Tração
6.
Sci Rep ; 9(1): 9205, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31235778

RESUMO

In this study, to explain the possibility of hydrogen transfer paths from manure to coal, Elbistan lignite (EL) combined with manure liquefaction of oil + gas products were analysed with Gas Chromatography-Mass Spectroscopy (GC-MS) and Nuclear Magnetic Resonance Spectroscopy (1H-NMR) technique. In the same way, it is observed that oils which as they fragment to an alkane-alkene mixture, serve as a hydrogen "sponge" and put a serious hydrogen need on the parts of the free radicals and molecules that are currently hydrogen poor. Concerning Elbistan lignite and manure do not have any aromatic hydrogen. Moreover, when the aromatic compounds were hydrogenated, their aromatic hydrogen was transformed to naphthenic hydrogen. Hydrogen transfer was due to isomerization of heptane from 3-methylhexane obtained in test oil where only manure was present as hydrogen donor in the liquefaction environment despite hydrogenation of isomerization from naphthalene to azulene.

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