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1.
Sci Total Environ ; 732: 139288, 2020 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-32438182

RESUMEN

The increase in volume in bio-waste is inseparable from the production of biomass derived commodities. To reduce the use of conventional resources, the valorization of waste streams is gaining importance, and the valorisation of poultry litter fits perfectly into such scheme. This study shows a possible valorization of wet torrefied (300 °C) poultry litter (WTPL) through activation and its further use as a fertilizer, and as a wastewater micro-pollutant absorbent. The WTPL was activated thermally, physically (CO2) and chemically (KOH) at two different temperatures (600 °C and 800 °C) and 30 min residence time. The properties of ACs were evaluated based on results of the elemental and proximate analysis, suspension pH measurement, ICP-OES, FT-IR, N2 and CO2 adsorption and quantity of absorbed methylene blue (MB). The yields in thermal and physical ACs were comparable, but much higher than ACs from chemical activation (c.a. 50% and 15% at 600 °C and c.a. 47% and 6.5% at 800 °C). The thermal and physical ACs showed good suitability for application as a fertilizer due to their high macro- and micro-nutrients and low heavy metals concentration. Carbons activated with KOH proved their usefulness as wastewater pollutant absorbers through high MB's absorption (675.8 mg/g for 600 °C and 872.8 mg/g for 800 °C). Results state that the valorization of PL through activation is possible, and the selection of the activation method affects the final application of obtained material.

2.
Vet J ; 256: 105436, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32113585

RESUMEN

Because the alveolar macrophage (AM) phenotype of horses with severe equine asthma (SEA) is unknown, the cytokines expressed by M1- and M2-polarized AM were determined and the hypothesis that natural hay/straw challenge (NC) induces divergent AM phenotypes in control horses and horses with SEA was tested. Macrophages from control horses were activated either with eIFNγ + lipolysaccharide (LPS) or eIL-4 to characterize M1- or M2-polarized AM gene expression, respectively and determine the response of polarized cells to pathogen-associated molecular patterns (PAMPS): LPS, zymosan, peptidoglycan and hay dust. Subsequently, gene expression was explored in AM of control horses and horses with SEA at pasture and after NC. M1 polarization increased expression of pro-inflammatory cytokines (TNFα, IL-8, IL-12p40), IL-10, and CD80. M2 polarization increased CD206 and down-regulated arginase-II and IL-10. Expression of pro-inflammatory cytokines and CD80 in response to PAMPS was further increased by M1 pre-polarization whereas M2 pre-polarization down-regulated expression of pro-inflammatory cytokines and IL-10 but increased CD206. In horses with SEA, AMs had elevated expression of IL-10 both at pasture and after NC, but only after NC in control horses. CD206 expression increased in both groups during NC. At pasture, stimulation by PAMPS augmented expression of IL-8 and IL-10 in horses with SEA compared to control horses. NC eliminated this difference by selectively increasing expression of IL-10 in control horses. A fundamental shift in the macrophage phenotype in SEA is supported by consistently elevated production of IL-10. A similar non-canonical phenotype develops temporarily in control horses upon NC suggesting that AMs in horses with SEA have lost the ability to respond dynamically to environmental cues.


Asunto(s)
Asma/veterinaria , Enfermedades de los Caballos/fisiopatología , Macrófagos Alveolares/efectos de los fármacos , Animales , Asma/inmunología , Asma/fisiopatología , Citocinas/metabolismo , Polvo/inmunología , Regulación de la Expresión Génica , Enfermedades de los Caballos/inmunología , Caballos , Lipopolisacáridos/farmacología , Macrófagos Alveolares/metabolismo , Fenotipo , Poaceae/inmunología
3.
Bioresour Technol ; 293: 122117, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31520863

RESUMEN

This study has two targets: Studying the extraction of the initial protein content from brewer's spent grain and the impact of protein's extraction on the chemical-physical properties of produced hydrochars. The protein was extracted from brewer's spent grains using the pH-shifting method. The extracted protein was quantified and characterized by their amino acid profile. The hydrothermal treatment was applied at 190 °C and 220 °C for 0.5 h, 1 h, 2 h, and 4 h. The hydrochars and process water were collected and assayed. The hydrochar after protein extraction reveals the lowest yield to hydrochars (67.10-45.14%), higher C/N ratio (19.66-21.33) and lower ash content (1.52-1.72 wt%) compared to the hydrochar without extraction.


Asunto(s)
Grano Comestible , Agua
5.
Solid State Nucl Magn Reson ; 85-86: 12-18, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28342403

RESUMEN

A comparative analysis of the Czjzek's and Maurer's models of the joint distribution density of NMR quadrupole parameters has been carried out in view of their application to account for spectra broadening induced by local disorder in crystals. As an example of such an application, we have considered Magic Angle Spinning NMR of 11B and 71Ga isotopes in polycrystalline gallium borate. Computer simulations carried out using both models unambiguously show that in the case of low local disorder the Maurer's model, in contrast to the Czjzek's model, provides satisfactory fits to experimental NMR spectra.

6.
Appl Magn Reson ; 48(2): 115-124, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28179750

RESUMEN

Temperature dependencies of 27Al and 23Na nuclear magnetic resonance spectra and spin-lattice relaxations in mordenite have been studied in static and magic angle spinning regimes. Our data show that the spin-lattice relaxations of the 23Na and 27Al nuclei are mainly governed by interaction of nuclear quadrupole moments with electric field gradients of the crystal, modulated by translational motion of water molecules in the mordenite channels. At temperatures below 200 K, the dipolar interaction of nuclear spins with paramagnetic impurities becomes an important relaxation mechanism of the 23Na and 27Al nuclei.

7.
Appl Magn Reson ; 47: 895-902, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27489405

RESUMEN

The 1H nuclear magnetic resonance (NMR) spectra and the dipolar spin-lattice relaxation time T1D for 1H in the natural natrolite (Na2Al2Si3O10·2H2O) have been measured in the temperature range of 190-390 K. From the temperature transformations of 1H NMR spectra, it follows that at T > 300 K, the diffusion of water molecules along the nano-channels is observed. From experimental T1D data, it follows that the 180° flip motion of the water molecules takes place in natrolite. At low temperature (T < 250 K), the dipolar interaction with paramagnetic impurities as a relaxation mechanism of 1H nuclei becomes significant.

8.
Solid State Nucl Magn Reson ; 76-77: 24-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27035262

RESUMEN

Behavior of water molecules entrapped in nanochannels of zeolite mordenite has been investigated by (1)H NMR technique. The (1)H spectra and spin-lattice relaxation times in the laboratory and rotating frames, T1 and T1ρ, respectively, as well as the dipolar relaxation time T1D have been measured in the temperature range from 96 to 351K. Diffusion of water molecules along the channels was observed above ~200K. While in bulk liquid the dipolar ordered state of nuclear spins is not formed owing to complete motional average of dipolar interactions, we show that such a state is observed for mobile molecules confined in a restricted geometry. At temperatures below ~140K the relaxation was found to be mainly caused by interaction of (1)H nuclear spins with paramagnetic impurities. Complete lost of the fine structure of (1)H spectra above ~320 K is attributed to isotropic molecular reorientation or/and proton exchange. We show that the dipolar relaxation in mordenite is responsive to slow 180° reorientations of water molecules. The correlation times of nuclear and electron spin fluctuations were determined.

9.
J Phys Condens Matter ; 27(36): 365302, 2015 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-26302025

RESUMEN

We report on (13)C spin-lattice (R 1) and spin-spin (R 2) relaxation rate dependence on magic-angle-spinning (MAS) rate in highly purified synthetic nanodiamonds. Noticeable slowdown of both relaxation processes and reduction of nuclear spin diffusion coefficient D with increasing MAS rate was obtained. This effect is attributed to suppression of nuclear spin diffusion by MAS. We developed a theoretical approach that describes the MAS rate dependence of R 1, R 2 and D, allows quantitative analysis of the data and shows good compliance with the experiment.

10.
Solid State Nucl Magn Reson ; 70: 38-42, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26123567

RESUMEN

Mixed iron-gallium borate crystals Ga1-xFexBO3 have been studied by Magic Angle Spinning (MAS) NMR of (11)B isotope. Experimental MAS NMR spectra have been computer simulated using a laboratory-developed code. The quadrupole parameters and isotropic chemical shift for (11)B are consistent with threefold-coordination of boron atoms. A detailed fitting to the experimental NMR spectra reveals the existence of a certain local disorder in Ga1-xFexBO3 crystals.

11.
Solid State Nucl Magn Reson ; 66-67: 51-55, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25465482

RESUMEN

We report on (13)C nuclear spin-lattice relaxation time (T1) dependence on the magic-angle-spinning (MAS) rate in powder nanodiamond samples. We confirm that the relaxation is caused by interaction of nuclear spins with fluctuating electron spins of localized paramagnetic defects. It was found that T1 is practically not affected by MAS for small particles, while for larger particles with lower defect density T1 is different in static and MAS regimes and reveals elongation with increasing MAS rate. This effect is attributed to suppression of nuclear spin diffusion by MAS. We propose an approach that describes T1 dependence on the MAS rate and allows quantitative analysis of this effect.

12.
J Phys Condens Matter ; 25(24): 245303, 2013 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-23709490

RESUMEN

We report on the first nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) study of the high-temperature nanodiamond-to-onion transformation. (1)H, (13)C NMR and EPR spectra of the initial nanodiamond samples and those annealed at 600, 700, 800 and 1800 ° C were measured. For the samples annealed at 600 to 800 ° C, our NMR data reveal the early stages of the surface modification, as well as a progressive increase in sp(2) carbon content with increased annealing temperature. Such quantitative experimental data were recorded for the first time. These findings correlate with EPR data on the sensitivity of the dangling bond EPR line width to air content, progressing with rising annealing temperature, that evidences consequent graphitization of the external layers of the diamond core. The sample annealed at 1800 ° C shows complete conversion of nanodiamond particles into carbon onions.

13.
Int J Med Robot ; 8(2): 184-90, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22190547

RESUMEN

BACKGROUND: In contemporary surgical clinical practice, spinal instability is often treated with mechanical stabilization techniques in order to protect the spinal cord and nerve roots. These techniques involve placing screws in defined regions of the vertebrae, typically the pedicle, where the strongest bone is found. The challenge for the surgeon is the accurate placement of screws for good mechanical purchase and to avoid damage to surrounding vital anatomical structures. This is especially critical in the cervical region, where the target bone mass is smaller and the spinal cord, nerve roots and vertebral arteries are all at risk. A robotic system enabling the surgeon to precisely place implants into the vertebrae should enhance safety and may potentially improve surgical results. METHODS: We describe such a system, which consists of a compact robot positioned using a passive structure, an optical tracking system, a surgical input device and planning and navigational software. The implant trajectory in each vertebra is planned preoperatively, using fine-cut computerized tomography (CT) scans. During surgery, registration matching between the CT scan and the patient's anatomy is achieved using point to point registration, refined with a surface merge technique. Approximate robot positioning is done passively by the surgeon. Final precise instrument positioning is performed by the robot according to the planned trajectory through the target vertebra. Implants (screws) are then placed through the robot-guided working channel. RESULTS: Six cadaver experiments, consisting of placing transarticular (i.e. crossing the joints between the vertebrae) screws in the upper two vertebrae of the human cervical spine, were performed. Implant placement accuracy was comparable with that achieved using freehand image-guided techniques by an experienced surgeon. CONCLUSIONS: These results confirm the utility and applicability of the system. It is currently in redesign to improve accuracy and to render it compatible with on-line planning.


Asunto(s)
Vértebras Cervicales/cirugía , Procedimientos Ortopédicos/instrumentación , Columna Vertebral/cirugía , Tornillos Óseos , Cadáver , Diseño de Equipo , Ergonomía , Estudios de Factibilidad , Humanos , Neuronas/patología , Procedimientos Ortopédicos/métodos , Reproducibilidad de los Resultados , Robótica , Programas Informáticos , Cirugía Asistida por Computador , Tomografía Computarizada por Rayos X/métodos
14.
AJNR Am J Neuroradiol ; 32(10): 1783-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21852373

RESUMEN

BACKGROUND AND PURPOSE: MDCT has some specific scan parameters that may systematically increase or decrease radiation dose to patients. This study explored the scan protocol parameters that impact radiation dose in temporal bone MDCT and determined the optimal scan parameters that balance radiation dose with diagnostic image quality. MATERIALS AND METHODS: Using exsomatized cadaveric heads, traditional axial scanning, and helical scanning were performed with different detector collimations. Helical scans of the same scan region were then acquired by using the determined optimal detector collimation and various tube voltages, whereas other scan parameters remained fixed. Next, the scans were repeated by using various tube current-time products by using the determined optimal tube voltage. Last, with fixed tube current-time product, the scans were repeated with various pitches. All thin-section, helically acquired scans were reformatted to axial and coronal images with respect to the relevant scanning baseline. In each of the image volumes, the mean and SD HU values in regions of interest were measured in the central section of the internal auditory canal, and CNR values were calculated. RESULTS: In agreement with theory, wider detector collimations such as 16 × 0.625 mm and 64 × 0.625 mm were associated with lower radiation doses than narrower collimations due to their lower overbeaming and higher geometric efficiency. In helical scanning, the detector collimation of 16 × 0.625 mm had higher image quality and the minimum DLP. Axial and coronal images acquired by using a 140-kVp tube voltage had significantly lower noise than scans acquired at 120 or 80 kVp with equivalent volume CT dose index. Diagnostic image quality was achieved when using a minimum tube current-time product of 120 mAs. Noise, CNR, and dose were jointly optimized with a pitch of 0.685. CONCLUSIONS: Temporal bone CT scanning parameters may be optimized by following a systematic procedure that allows for the optimization of diagnostic image quality and the minimization of radiation dose. One such procedure for a particular 64-section MDCT scanner has been presented.


Asunto(s)
Carga Corporal (Radioterapia) , Dosis de Radiación , Protección Radiológica/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Hueso Temporal/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
15.
Int J Tuberc Lung Dis ; 14(9): 1097-103, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20819253

RESUMEN

OBJECTIVE: To explore grant and country characteristics associated with the performance of tuberculosis (TB) grants supported by the Global Fund to Fight AIDS, Tuberculosis and Malaria (Global Fund), which uses performance-based funding of grants. METHODS: We used Global Fund grant data to compute the average programmatic performance of 108 TB grants in 88 countries. Using stepwise regression models, we examined the correlation of grant performance with a range of grant and country characteristics. RESULTS: Funding duration and funding per estimated smear-positive TB case were positively correlated with grant performance (partial correlations of 0.386-0.416 for the former, 0.200 for the latter). Successful completion of an evaluation of a grant during the second year of funding was linked to higher performance (0.357). Performance was further influenced by the independent organisation hired by the Global Fund to provide ongoing monitoring of the grants (0.197-0.243). Two country-specific factors were significantly correlated with performance: political stability (0.197-0.234) and disease burden (-0.211). DISCUSSION: Successful evaluation that leads to continued funding predicts higher performance of TB grants, even in challenging settings such as weak health services. However, other contextual factors affect grant performance and should be considered when assessing grants to ensure that countries that have a high disease burden and are politically unstable are not penalized.


Asunto(s)
Organización de la Financiación/organización & administración , Salud Global , Tuberculosis/economía , Humanos , Política , Análisis de Regresión , Tuberculosis/prevención & control , Tuberculosis/terapia
16.
Oncogene ; 28(48): 4284-94, 2009 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-19749793

RESUMEN

p53 as an unstable protein in vitro likely requires stabilizing factors to act as a tumor suppressor in vivo. Here, we show that in human cells transfected with wild-type (WT) p53, Hsp90 and Hsp70 molecular chaperones maintain the p53 native conformation under heat-shock conditions (42 degrees C) as well as assist p53 refolding at 37 degrees C, during the recovery from heat shock. We also show that the interaction of WT p53 with WAF1 promoter in cells is sensitive to Hsp70 and Hsp90 inhibition already at 37 degrees C and further decreased on heat shock. The influence of chaperones on p53 binding to the WAF1 promoter sequence has been confirmed in vitro, using highly purified proteins. Hsp90 stabilizes the binding of p53 to the promoter sequence at 37 degrees C, whereas under heat-shock conditions the requirement for the Hsp70-Hsp40 system and its cooperation with Hsp90 increases. Hop co-chaperone additionally stimulates these reactions. Interestingly, the combined Hsp90 and Hsp70-Hsp40 allow for a limited in vitro restoration of the DNA-binding activity by the p53 oncogenic variant R249S and affect its conformation in cells. Our results indicate for the first time that, especially under stress conditions, not only Hsp90 but also Hsp70 is required for the chaperoning of WT and R249S p53.


Asunto(s)
Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Respuesta al Choque Térmico/genética , Pliegue de Proteína , Proteína p53 Supresora de Tumor/metabolismo , Sitios de Unión , Proteínas HSP70 de Choque Térmico/química , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP90 de Choque Térmico/química , Proteínas HSP90 de Choque Térmico/genética , Humanos , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/química
17.
Solid State Nucl Magn Reson ; 34(3): 167-74, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18783926

RESUMEN

The analytical solution for the Kubo-Anderson oscillator with a fluctuating frequency omega for arbitrary distribution function p(omega) has been obtained. The obtained theoretical expression has been applied to consideration of some dynamical problems of solid state NMR, namely (1) dynamical transformation of NMR line shape and spin-echo signal and (2) the temperature transformation of the second moment of NMR line for the case, when the potential barrier for the mobility of magnetic nuclei is a stochastic function of time.

18.
J Biomech Eng ; 128(1): 40-8, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16532616

RESUMEN

Coronary artery disease (CAD) is characterized by the progression of atherosclerosis, a complex pathological process involving the initiation, deposition, development, and breakdown of the plaque. The blood flow mechanics in arteries play a critical role in the targeted locations and progression of atherosclerotic plaque. In coronary arteries with motion during the cardiac contraction and relaxation, the hemodynamic flow field is substantially different from the other arterial sites with predilection of atherosclerosis. In this study, our efforts focused on the effects of arterial motion and local geometry on the hemodynamics of a left anterior descending (LAD) coronary artery before and after clinical intervention to treat the disease. Three-dimensional (3D) arterial segments were reconstructed at 10 phases of the cardiac cycle for both pre- and postintervention based on the fusion of intravascular ultrasound (IVUS) and biplane angiographic images. An arbitrary Lagrangian-Eulerian formulation was used for the computational fluid dynamic analysis. The measured arterial translation was observed to be larger during systole after intervention and more out-of-plane motion was observed before intervention, indicating substantial alterations in the cardiac contraction after angioplasty. The time averaged axial wall shear stress ranged from -0.2 to 9.5 Pa before intervention compared to -0.02 to 3.53 Pa after intervention. Substantial oscillatory shear stress was present in the preintervention flow dynamics compared to that in the postintervention case.


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/cirugía , Vasos Coronarios/fisiopatología , Vasos Coronarios/cirugía , Modelos Cardiovasculares , Velocidad del Flujo Sanguíneo , Presión Sanguínea , Simulación por Computador , Humanos , Flujo Pulsátil , Resistencia al Corte , Resultado del Tratamiento
19.
Cytotherapy ; 7(1): 57-61, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16040384

RESUMEN

BACKGROUND: Wilms' tumor 1 (WT1) gene expression is seen in a significant number of cases of human neoplasia; however, the mechanism of action remains to be clarified. We hypothesized that WT1 gene is a surrogate marker of proliferation in normal hematopoietic cells and leukemias. While we and others have recognized its value as a tool for the detection of minimal residual disease (MRD), the objective of this study was to confirm our hypothesis regarding normal. METHODS: Samples from healthy donors (n=16) and UC blood (n=9) were cultured in Methocult for 21 days. Colonies were analyzed on days 7, 14 and 21 by RT-PCR for WT1 gene expression. Our positive controls were samples from patients with leukemia (n=91). Negative controls were from normal volunteers without stimulation (n=26). RESULTS: Results showed a statistically significant difference (P<0.0001) between cultured groups, with the highest level of WT1 gene expression in the positive controls and on day 14, when cells are at their maximal proliferation. DISCUSSION: In conclusion, WT1 gene expression in the proliferating colonies was highest on day 14, although less than in leukemia samples, confirming our hypothesis that WT1 gene is a surrogate marker of proliferation, not only in leukemogenesis but also, to a lesser degree, in normal cell proliferation.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Genes del Tumor de Wilms/fisiología , Células Madre Hematopoyéticas/metabolismo , Leucemia/diagnóstico , Leucemia/genética , Proteínas WT1/genética , Células Cultivadas , Citocinas/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Marcadores Genéticos/genética , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Valor Predictivo de las Pruebas , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/genética
20.
Solid State Nucl Magn Reson ; 25(1-3): 15-20, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14698379

RESUMEN

A general equation for the dipolar correlation function, to be used to analyze various kinds of independent internal motions, described by some correlation times tau(cm) (m = 1,2 em...k), has been obtained. The obtained expression has been used to analyze the temperature dependencies of different NMR measured values: second moment: spin-lattice relaxation times; amplitude of solid echoes signals.

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