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1.
Waste Manag Res ; 41(5): 1026-1035, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36564864

RESUMEN

This study evaluated the effects of increased temperature and leachate recirculation on volatile solids (VS), biogas, hydrogen sulphide (H2S) leachate quality (pH and chemical oxygen demand) and the settlement of municipal solid waste (MSW). Three large-scale tests were conducted with no leachate recirculation at 21°C, weekly leachate recirculation at 20°C and weekly leachate recirculation at 50°C. Leachate recirculation and increased temperature accelerated biodegradation and pushed forward the onset time (from 27 to 8 days). The increase of biodegradation activity was reflected in the change of biogas production, VS and settlement. Compressibility index Cc, increased from 0.71 and 0.77 at 21°C to 0.83 when the temperature was 50°C. In addition, leachate recirculation and high temperature reduced H2S concentration levels by inhibiting the growth of sulphate-reducing bacteria and leachate recirculation lowered H2S production by dissolving the high H2S presence. The results showed that MSW can have significantly changed mechanical and biochemical behaviour under different temperatures and saturations. The results help understand the processes in landfills for more effective short-term and long-term design and management.


Asunto(s)
Eliminación de Residuos , Contaminantes Químicos del Agua , Residuos Sólidos/análisis , Eliminación de Residuos/métodos , Temperatura , Biocombustibles , Reactores Biológicos , Biodegradación Ambiental , Instalaciones de Eliminación de Residuos , Contaminantes Químicos del Agua/análisis
2.
Waste Manag Res ; 40(7): 987-997, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34753375

RESUMEN

A Municipal Solid Waste Borehole Assessment (MBA) was developed to assess in situ geotechnical properties of municipal solid waste (MSW) during the boring of gas extraction well construction. A Large-Diameter Borehole Caliper (LDBC) was lowered into the borehole to measure the diameter and record the condition of the wall by time-lapse video photography. The results indicated that the borehole experienced significant radial compression with depth following completion. Radial compressions amounted to approximately 7.5% at 9.14 m, 10% at 21.3 m and 11% at 27.4 m below ground surface. The bulk modulus was estimated by using the captured volumetric strains and reported lateral earth coefficients, and the results showed that it increases with increasing depth. For MSW, the bulk modulus increased up to 13.4 MPa in a linear trend with depth. The unit weights of MSW were obtained using three diameter readings from LDBC, auger barrel outside diameter and outer cutting bit outside diameter. The results showed that the diameter based on outer cutting bit yielded realistic unit weights (5.08-9.68 kN m-3) due to unrealistic calculated saturations by other two assumed diameters. The borehole assessment with LDBC was shown to be an efficient and valuable means for characterising MSW and effectively designing gas extraction wells. The research provided a means to assess the waste mass with accuracy at great depths by directly observing and measuring borehole condition.


Asunto(s)
Eliminación de Residuos , Residuos Sólidos , Presión , Eliminación de Residuos/métodos , Residuos Sólidos/análisis , Instalaciones de Eliminación de Residuos
3.
Clin Exp Immunol ; 204(1): 14-31, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33306199

RESUMEN

The distinction of self from non-self is crucial to prevent autoreactivity and ensure protection from infectious agents and tumors. Maintaining the balance between immunity and tolerance of immune cells is strongly controlled by several sophisticated regulatory mechanisms of the immune system. Among these, the E3 ligase ubiquitin Casitas B cell lymphoma-b (Cbl-b) is a newly identified component in the ubiquitin-dependent protein degradation system, which is thought to be an important negative regulator of immune cells. An update on the current knowledge and new concepts of the relevant immune homeostasis program co-ordinated by Cbl-b in different cell populations could pave the way for future immunomodulatory therapies of various diseases, such as autoimmune and allergic diseases, infections, cancers and other immunopathological conditions. In the present review, the latest findings are comprehensively summarized on the molecular structural basis of Cbl-b and the suppressive signaling mechanisms of Cbl-b in physiological and pathological immune responses, as well as its emerging potential therapeutic implications for immunotherapy in animal models and human diseases.


Asunto(s)
Enfermedades Autoinmunes/terapia , Hipersensibilidad/terapia , Inmunoterapia/métodos , Neoplasias/terapia , Proteínas Proto-Oncogénicas c-cbl/inmunología , Animales , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/metabolismo , Homeostasis/inmunología , Humanos , Hipersensibilidad/inmunología , Hipersensibilidad/metabolismo , Sistema Inmunológico/citología , Sistema Inmunológico/inmunología , Sistema Inmunológico/metabolismo , Neoplasias/inmunología , Neoplasias/metabolismo , Proteínas Proto-Oncogénicas c-cbl/metabolismo , Ubiquitina/inmunología , Ubiquitina/metabolismo
4.
J Chem Phys ; 153(22): 224703, 2020 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-33317278

RESUMEN

The surface plasmon response of a cross-sectional segment of a wrinkled gold film is studied using electron energy loss spectroscopy (EELS). EELS data demonstrate that wrinkled gold structures act as a suitable substrate for surface plasmons to propagate. The intense surface variations in these structures facilitate the resonance of a wide range of surface plasmons, leading to the broadband surface plasmon response of these geometries from the near-infrared to visible wavelengths. The metallic nanoparticle boundary element method toolbox is used to simulate plasmon eigenmodes in these structures. Eigenmode simulations show how the diverse morphology of the wrinkled structure leads to its high spectral complexity. Micron-sized structural features that do not provide interactions between segments of the wrinkle have only a small effect on the surface plasmon resonance response, whereas nanofeatures strongly affect the resonant modes of the geometry. According to eigenmode calculations, different eigenenergy shifts around the sharp folds contribute to the broadband response and infrared activity of these structures; these geometrical features also support higher energy (shorter wavelength) symmetric and anti-symmetric plasmon coupling across the two sides of the folds. It is also shown that additional plasmon eigenstates are introduced from hybridization of modes across nanogaps between structural features in close proximity to each other. All of these factors contribute to the broadband response of the wrinkled gold structures.

5.
Unfallchirurg ; 122(12): 950-957, 2019 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-30680414

RESUMEN

BACKGROUND: The γ­nailing system is a widespread intramedullary therapeutic option that has been used for intertrochanteric and subtrochanteric fractures since the late 1980s; however, some reports from the 1990s describing femoral shaft fractures questioned the indications for this system in simple fracture types. Due to increasing numbers of patients treated with this system, the complication rate is continuously falling as confirmed by many recent studies. OBJECTIVE: Between 2008 and 2013 a total of 1500 operations using the γ­nailing system were performed at this traumatology department. The standard 200 mm nail was used in 1290 cases and the extended system available from 340 to 440 mm in 210 cases. The aim of this study was to record the excellent results using the standard γ­nailing system and to confirm the indications of the long intramedullary nailing system (Gamma3®) also for use in complex intertrochanteric and subtrochanteric fractures. MATERIAL AND METHODS: All 1500 patients were retrospectively analyzed. Information on epidemiological data, intraoperative and postoperative complications and patient outcome was retrieved from the digital patient medical history. All available radiographs were assessed by a single traumatologist. RESULTS: The results showed a low complication rate of 5% for surgical complications, mainly caused by cutting out in 34.66%, followed by hematomas in 21.33% and fractures of the nail in 16%. A comparison of the standard and long nailing systems could be carried out, showing a complication rate of 3.64% for the standard system compared to 13.33% for the long γ­nail system. CONCLUSION: The γ­nailing system is a safe treatment option for trochanteric femoral fractures and failure of the implant is associated with high biomechanical forces in unstable fractures. A low complication rate is linked to a thorough surgical technique under consideration of a correct positioning of the implant.


Asunto(s)
Fijación Intramedular de Fracturas , Fracturas del Húmero , Fracturas del Hombro , Clavos Ortopédicos , Estudios de Seguimiento , Humanos , Fracturas del Húmero/cirugía , Reoperación , Estudios Retrospectivos , Fracturas del Hombro/cirugía
6.
Artículo en Inglés | MEDLINE | ID: mdl-26856977

RESUMEN

Number of days spent in acute hospitals (DAH) at the end of life is regarded as an important care quality indicator for cancer patients. We analysed DAH during 90 days prior to death in patients from four Swiss cantons. Claims data from an insurance provider with about 20% market share and patient record review identified 2086 patients as dying of cancer. We calculated total DAH per patient. Multivariable generalised linear modelling served to evaluate potential explanatory variables. Mean DAH was 26 days. In the multivariable model, using complementary and alternative medicine (DAH = 33.9; +8.8 days compared to non-users) and canton of residence (for patient receiving anti-cancer therapy, Zürich DAH = 22.8 versus Basel DAH = 31.4; for other patients, Valais DAH = 22.7 versus Ticino DAH = 33.7) had the strongest influence. Age at death and days spent in other institutions were additional significant predictors. DAH during the last 90 days of life of cancer patients from four Swiss cantons is high compared to most other countries. Several factors influence DAH. Resulting differences are likely to have financial impact, as DAH is a major cost driver for end-of-life care. Whether they are supply- or demand-driven and whether patients would prefer fewer days in hospital remains to be established.


Asunto(s)
Tiempo de Internación/estadística & datos numéricos , Neoplasias/terapia , Cuidado Terminal/estadística & datos numéricos , Enfermedad Aguda , Factores de Edad , Anciano , Femenino , Disparidades en Atención de Salud , Humanos , Masculino , Estudios Retrospectivos , Suiza
7.
Reprod Domest Anim ; 52(3): 459-467, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28176378

RESUMEN

This study was designed to investigate the effects of feeding-protected conjugated linoleic acid (CLA) on the semen production and sperm freezability in Holstein bulls. Twelve bulls were randomly assigned to two groups (n = 6 per group). Bulls received the normal diet (control group) or the normal diet top-dressed with 50 g of CLA (treated group) for 10 weeks. The control group received 40 g/day calcium soap of fatty acid. Fresh and post-thaw semen quality was assessed on ejaculates collected at the 0, 4, 6, 8 and 10 week of supplementation. Semen evaluations including sperm concentration, motion characteristics (subjective and computer-assisted), viability (Eosin-Nigrosin), membrane integrity (hypo-osmotic swelling test) and abnormality were conducted. Semen volume, sperm concentration and total sperm output were not affected by dietary treatment (p > .05). The proportion of spermatozoa with abnormal morphology in fresh semen significantly increased (p < .05) in the CLA-fed group compared to control group. Also, in CLA-fed group, the proportion of post-thaw spermatozoa with abnormal morphology at week 10 of trial was significantly higher in CLA than control group (p < .05). Progressive motility tended to be increased in the CLA-fed group, although dietary supplementation did not affect other CASA parameters or viability in fresh and frozen-thawed sperm. In this study, CLA supplementation had little positive effect on fresh or post-thaw sperm quality of Holstein bulls.


Asunto(s)
Bovinos , Criopreservación , Suplementos Dietéticos , Análisis de Semen/veterinaria , Espermatozoides/efectos de los fármacos , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Ácidos Grasos , Ácidos Linoleicos Conjugados/administración & dosificación , Ácidos Linoleicos Conjugados/farmacología , Masculino , Preservación de Semen , Motilidad Espermática/efectos de los fármacos
8.
Spinal Cord ; 53 Suppl 1: S10-2, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25900282

RESUMEN

OBJECTIVES: The purpose of this paper is to describe the development and evaluation of a new medial linkage reciprocating gait orthosis (MLRGO) that incorporates a reciprocal mechanism and is sensitive to pelvic motion to potentially assist paraplegic patients to walk and provide functional independence. CASE DESCRIPTION AND METHODS: The new orthosis was constructed and tested by a 20-year-old female paraplegic subject with transverse myelitis at T10 level, who was 4 years post injury and had also been an isocentric reciprocating gait orthosis (IRGO) user for 2 years. She received gait training for 12 weeks before undertaking gait analysis, and also completed a questionnaire that was designed to assess the perceived functionality of the new MLRGO when compared with an IRGO. RESULTS: The results demonstrated improvements in gait velocity, step length and cadence, and also improvement in functional independence with the new orthosis compared with an IRGO. CONCLUSION: The results demonstrated that this new MLRGO could be used for paraplegic patients who would like an improvement in functional independence and ambulation.


Asunto(s)
Aparatos Ortopédicos , Traumatismos de la Médula Espinal/fisiopatología , Traumatismos de la Médula Espinal/rehabilitación , Caminata/fisiología , Fenómenos Biomecánicos , Femenino , Cadera/fisiopatología , Humanos , Movimiento , Rango del Movimiento Articular , Encuestas y Cuestionarios , Adulto Joven
9.
Spinal Cord ; 53(5): 380-6, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25384401

RESUMEN

STUDY DESIGN: A feasibility study on the effect of a new reciprocating orthosis on specific gait parameters for use by people with spinal cord injury. OBJECTIVES: The aim of this study was to design and develop a new medial linkage orthosis (MLO) mechanism incorporating a reciprocating motion and to determine its efficacy in improving specific spatiotemporal, kinematic and kinetic parameters while ambulating when worn by healthy subjects. This was achieved via the use of a lower limb paralysis simulator (LLPS). METHODS: A reciprocating joint with a remote center of motion was designed for use as an MLO. A prototype was fabricated and incorporated into an orthosis and equipped with a saddle to make the reciprocating motion possible. The efficacy of the orthosis was evaluated on four able-bodied healthy subjects who were trained to walk with the MLO attached to the LLPS. RESULTS: Mean walking speed, stride length, stride time and cadence was 0.09±0.007 m s(-1), 0.42±0.01 m, 4.89±0.45 s and 29.54±4.32 steps min(-1), respectively, when healthy subjects walked with the new orthosis. The mean hip joint torque produced was 0.36±0.13 Nm. CONCLUSION: In this study a new MLO was designed and fabricated that provided a reciprocating mechanism using a four-bar mechanism to set the virtual axis of the mechanism in a more proximal position than hinge-type joints. Further investigation is currently underway to assess its effect on gait parameters and energy expenditure in paraplegic patients.


Asunto(s)
Diseño de Equipo , Locomoción/fisiología , Extremidad Inferior/fisiopatología , Aparatos Ortopédicos , Parálisis/patología , Traumatismos de la Médula Espinal/rehabilitación , Adolescente , Adulto , Fenómenos Biomecánicos , Estudios de Factibilidad , Femenino , Articulación de la Cadera/fisiopatología , Humanos , Masculino , Parálisis/etiología , Rango del Movimiento Articular , Estadísticas no Paramétricas , Adulto Joven
10.
Public Health ; 126(9): 796-803, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22910445

RESUMEN

OBJECTIVES: Social capital is associated with a number of sociodemographic characteristics and health outcomes. This study aimed to assess the components of social capital, and determine its association with different demographic features and general health in Tehran. STUDY DESIGN: A large population-based cross-sectional survey was conducted using the Urban Health Equity Assessment and Response Tool (Urban-HEART). METHOD: A comprehensive questionnaire containing 13 sections, including a specific tool to measure social capital, was administered to 22,300 randomly selected clustered sample households within all 22 districts in Tehran between June and September 2008. The social capital questionnaire consists of two main components - structural and cognitive - which measure collective activities, voluntary help, social cohesion, social network, reciprocity and trust. The first question of Short Form-12 was used to evaluate self-rated health. Descriptive statistics, contingency tables, independent sample t-test, analysis of variance, post-hoc test (least squares difference) and multiple linear regression were used to detect differences. A P-value <0.01 was considered to indicate significance. RESULTS: The social capital questionnaire and health-related quality-of-life tool were completed by 21,704 individuals (response rate 97%) in all 22 districts of Tehran. All social capital components apart from participation varied by age group and gender (P < 0.01). An improvement was seen in several social capital components with increased level of education (P < 0.01). All social capital elements apart from volunteering were associated with marital status (P < 0.01). Family size, family assets and length of residence in neighbourhood were considered to be determinants of social capital (P < 0.01), and respondents with better health showed higher levels of social capital (P < 0.0001). CONCLUSION: Various individual and household characteristics influence social capital. General health and social capital are mutually and independently correlated with other determinants, so improvements in either may lead to higher levels of social capital and well-being.


Asunto(s)
Estado de Salud , Clase Social , Apoyo Social , Adolescente , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Irán , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto Joven
11.
Sci Rep ; 12(1): 17462, 2022 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-36261495

RESUMEN

The energy resolution in hyperspectral imaging techniques has always been an important matter in data interpretation. In many cases, spectral information is distorted by elements such as instruments' broad optical transfer function, and electronic high frequency noises. In the past decades, advances in artificial intelligence methods have provided robust tools to better study sophisticated system artifacts in spectral data and take steps towards removing these artifacts from the experimentally obtained data. This study evaluates the capability of a recently developed deep convolutional neural network script, EELSpecNet, in restoring the reality of a spectral data. The particular strength of the deep neural networks is to remove multiple instrumental artifacts such as random energy jitters of the source, signal convolution by the optical transfer function and high frequency noise at once using a single training data set. Here, EELSpecNet performance in reducing noise, and restoring the original reality of the spectra is evaluated for near zero-loss electron energy loss spectroscopy signals in Scanning Transmission Electron Microscopy. EELSpecNet demonstrates to be more efficient and more robust than the currently widely used Bayesian statistical method, even in harsh conditions (e.g. high signal broadening, intense high frequency noise).


Asunto(s)
Imágenes Hiperespectrales , Procesamiento de Imagen Asistido por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Inteligencia Artificial , Teorema de Bayes , Redes Neurales de la Computación
12.
Microscopy (Oxf) ; 71(Supplement_1): i174-i199, 2022 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-35275180

RESUMEN

Nowadays, sub-50 meV atom-wide electron probes are routinely produced for electron energy loss spectroscopy in transmission electron microscopes due to monochromator technology advances. We review how gradual improvements in energy resolution enabled the study of very low-energy excitations such as lattice phonons, molecular vibrations, infrared plasmons and strongly coupled hybrid modes in nanomaterials. Starting with the theoretical framework needed to treat inelastic electron scattering from phonons in solids, we illustrate contributions in detecting optical surface phonons in photonic structures. We discuss phonon mapping capabilities in real and reciprocal space, and the localized phonon response near nano-/atomic-scale structural features. We also survey the progress of aloof spectroscopy in studying vibrations in organic materials and applications in measuring local temperature and photonic density of states in single nanostructures using phonon scattering. We then turn towards studies on infrared plasmons in metals and semiconductors. Spectroscopy analyses now extend towards probing extremely complex broadband platforms, the effects of defects and nanogaps, and some far-reaching investigations towards uncovering plasmon lifetime and 3D photonic density of states. In doped semiconductors, we review research on the use of the electron probe to correlate local doping concentration and atomic-scale defects with the plasmonic response. Finally, we discuss advances in studying strong coupling phenomena in plasmon-exciton and plasmon-phonon systems. Overall, the wealth of information gained extends our knowledge about nanomaterial properties and elementary excitations, illustrating the powerful capabilities of high-energy resolution scanning transmission electron microscopy-electron energy loss spectrometry.

13.
Anal Biochem ; 411(2): 176-84, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21236237

RESUMEN

A double-stranded calf thymus DNA (dsDNA) was physisorbed onto a polypyrrole (PPy) nanofiber film that had been electrochemically deposited onto a Pt electrode. The surface morphology of the polymeric film was characterized using scanning electron microscopy (SEM). The electrochemical characteristics of the PPy film and the DNA deposited onto the PPy modified electrode were investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). Then the interaction of DNA with salicylic acid (SA) and acetylsalicylic acid (ASA), or aspirin, was studied on the electrode surface with DPV. An increase in the DPV current was observed due to the oxidation of guanine, which decreased with the increasing concentrations of the ligands. The interactions of SA and ASA with the DNA follow the saturation isotherm behavior. The binding constants of these interactions were 1.15×10(4)M for SA and 7.46×10(5)M for ASA. The numbers of binding sites of SA and ASA on DNA were approximately 0.8 and 0.6, respectively. The linear dynamic ranges of the sensors were 0.1-2µM (r(2)=0.996) and 0.05-1mM (r(2)=0.996) with limits of detection of 8.62×10(-1) and 5.24×10(-6)µM for SA and ASA, respectively.


Asunto(s)
Aspirina/química , ADN/química , Espectroscopía Dieléctrica/métodos , Técnicas Electroquímicas/métodos , Nanofibras/química , Ácido Salicílico/química , Animales , Bovinos , Electrodos , Guanina/química , Oxidación-Reducción , Polímeros/química , Pirroles/química
14.
J Biomater Sci Polym Ed ; 32(5): 678-693, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33250001

RESUMEN

Poly(dimethylsiloxane) (PDMS) elastomer is now a well-known material for packaging implantable biomedical micro-devices owing to unique bulk properties such as biocompatibility, low toxicity, excellent rheological properties, good flexibility, and mechanical stability. Despite the desirable bulk characteristics, PDMS is generally regarded as a high-flux material for oxygen and water vapor to penetrate compared with other polymeric barrier materials, which is related to the defect-induced penetration through the packaging coating prepared by the traditional deposition techniques. Besides, its hydrophobic nature causes serious fouling problems and limits the practical application of PDMS-based devices. In this work, the performance of silicone thin films as a packaging layer was improved by the fabrication of the roller-casted multiple thin layers to minimize a defect-induced failure. To confer hydrophilicity and cell fouling resistance, high-density and well-defined poly(oligo(ethylene glycol) methacrylate) (POEGMA) brushes were tethered via the surface-initiated atom transfer radical polymerization (SI-ATRP) technique on the roller-casted multiple thin PDMS layers. The characteristics of fabricated substrates were determined by static water contact angle measurement, X-ray photoelectron spectroscopy, and attenuated total reflection-Fourier transform infrared spectroscopy. In vitro cell behavior of POEGMA-grafted PDMS substrates was evaluated to examine cell-fouling resistance.


Asunto(s)
Incrustaciones Biológicas , Incrustaciones Biológicas/prevención & control , Adhesión Celular , Metacrilatos , Polimerizacion , Polímeros , Propiedades de Superficie
15.
J Air Waste Manag Assoc ; 71(4): 433-446, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33180006

RESUMEN

This study is to analyze geotechnical properties and biological status of undisturbed municipal solid waste (MSW) associated with depth by using a large-diameter borehole sampling method. Through the method, a 28 m-borehole with 0.8 m of the diameter was drilled into the MSW body consisting of ten-lift layers of waste placed over 4000 days in an operating landfill. MSW sample cuttings were collected from the field site, weighted, and transferred to a laboratory for additional experiments to measure various properties such as moisture content, constituent characterization, unit weights, specific gravity, decomposition state, saturation, and compression rates with regard to waste depth. Also, the methane production obtained from MSW decomposition tests indicated that waste mass was relatively consistent throughout the depth of borehole and had not reached the accelerated production phase of methane. The wet and dry unit weights of the MSW sample with different depths produced excellent trends of the first-order rate with vertical stress. First Oder Rate Equation (FORE) analysis indicated that the maximum total and dry unit weight of MSW (γMSWw and γMSWd) achieved at depth in the waste mass were 12.9 kN/m3 and 10.6 kN/m3, respectively. Based on the waste shrinkage ratio (WSR) defined as the initial dry unit weight divided by succeeding dry unit weight, the height of the original MSW pile was estimated to be 40.5 m. Different compression parameters, including aggregated MSW compression index (Cc), modified compression index (CCE), and compression ratio parameter (Cc'), were comparably evaluated, which can be beneficial to understand compressibility and settlement processes in a landfill.Implications: Geotechnical properties and biological status of undisturbed municipal solid waste (MSW) associated with depth were analyzed by using a large-diameter borehole sampling method. The wet and dry unit weights of the MSW sample with different depths produced excellent trends of the first-order rate with vertical stress. Based on the waste shrinkage ratio (WSR) defined as the initial dry unit weight divided by succeeding dry unit weight, the height of the original MSW pile was estimated to be 40.5 m. Different compression parameters, including aggregated MSW compression index (Cc), modified compression index (CCE), and compression ratio parameter (Cc'), were comparably evaluated, which can be beneficial to understand compressibility and settlement processes in a landfill.


Asunto(s)
Eliminación de Residuos , Residuos Sólidos , Metano , Presión , Instalaciones de Eliminación de Residuos
16.
Br J Oral Maxillofac Surg ; 59(5): 561-566, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33863596

RESUMEN

Up until now, only a limited number of evidence-based studies with different results has evaluated traumatic nerve injury after maxillofacial surgery using piezoelectric devices versus rotary instruments. The present experiment was performed to evaluate damage to the inferior alveolar nerve (IAN), histologically, after osteotomy of the buccal cortex of the mandible using piezoelectric devices versus surgical handpieces. Forty rabbits underwent bilateral osteotomy of the mandibular buccal cortex. For the osteotomy of one side, piezoelectric devices were used, and for the other, conventional rotary handpieces. After cleavage of the osteotomised cortical bone segments, the exposed part of the IAN was excised and examined histologically for nerve injury. IAN damage was scored histologically from Grade 0 (no nerve damage) to Grade 4 (complete nerve transection). It was found that 25% and 17.5% of nerves had Grade 0; 17.5% and 10% had Grade 1; 25% and 20% had Grade 2; 17.5% and 27.5% had Grade 3; and 15% and 25% had Grade 4 injury in piezosurgery and rotary groups, respectively. Statistical analyses revealed no significant difference between groups in damage to the IAN. The present study showed that piezosurgery devices, similar to conventional rotary instruments, have the potential to cause severe nerve damage during surgery and should therefore be used with care.


Asunto(s)
Mandíbula , Nervio Mandibular , Animales , Mandíbula/cirugía , Boca , Osteotomía/efectos adversos , Piezocirugía , Conejos
17.
J Phys Chem A ; 114(37): 10209-16, 2010 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-20738138

RESUMEN

To develop a detailed picture of the bare Fe3 cluster structure, the nature of chemical bonding in this metal cluster is investigated by natural bond orbital (NBO) and natural resonance theory (NRT) analyses. The first part of the study clearly shows that the main factor governing the ground-state geometry of this cluster is the delocalized nature of the valence electrons. Highly unsaturated structure and the charge transfer list of Ωi → Ωj* NBO interactions of the parent reference Fe3 structure draw one's attention to the possible candidate structures presenting the correct electronic structure consistent with the observed optimized geometry of Fe3. In the other part of the study, different established modes of nitrogen coordination on Fe3 cluster are investigated. It is found that the most favored adsorption site for the associative attachment of N2 is the bridge site, with the binding energy of -17.6 kcal/mol. NBO analysis is also applied to present a detailed discussion of the metal-ligand interactions and the predominate role of the delocalized valence electrons.


Asunto(s)
Electrones , Hierro/química , Simulación de Dinámica Molecular , Nitrógeno/química , Teoría Cuántica , Adsorción , Propiedades de Superficie
18.
Food Sci Technol Int ; 16(6): 543-51, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21339170

RESUMEN

Fluid gels are known to be very shear-thinning materials with yield stress. In this study, the rheological properties of gellan and gellan-pectin fluid gels in fermented dairy drinks were evaluated using viscometric measurements. Both gellan- and gellan-pectin-containing solutions showed the rheological properties of fluid gels resulting in stabilization of particles; but no evidence of a fluid gel was observed for those with pectin alone and those with no hydrocolloid content. Unlike pectin, gellan gum was capable of creating significant values of yield stress and accordingly stabilized colloidal particles and extrinsic added solid particles in the fermented dairy drink. However, pectin improved the stability in combination with gellan. The origin of fluid gel formation was assumed to be both permanent interactions occurring between gellan and proteins, forming hairy particle gels and transient interactions between the particle gels. The significance of yield stress values for particle stability was demonstrated and two methods, including a noteworthy infinite apparent viscosity method and a conventional Bingham approach, were employed to calculate the values of yield stress. Both the methods showed a good application potential due to their simplicity, reasonable results and also wide availability of the instrument applied.


Asunto(s)
Bebidas/análisis , Productos Lácteos Cultivados/química , Fenómenos Químicos , Coloides , Geles , Fenómenos Mecánicos , Modelos Químicos , Pectinas/química , Polisacáridos Bacterianos/química , Reología , Resistencia al Corte , Viscosidad
19.
Artículo en Inglés | MEDLINE | ID: mdl-33094110

RESUMEN

Electroencephalography (EEG)-based brain-computer interface (BCI) systems infer brain signals recorded via EEG without using common neuromuscular pathways. User brain response to BCI error is a contributor to non-stationarity of the EEG signal and poses challenges in developing reliable active BCI control. Many passive BCI implementations, on the other hand, have the detection of error-related brain activity as their primary goal. Therefore, reliable detection of this signal is crucial in both active and passive BCIs. In this work, we propose CREST: a novel covariance-based method that uses Riemannian and Euclidean geometry and combines spatial and temporal aspects of the feedback-related brain activity in response to BCI error. We evaluate our proposed method with two datasets: an active BCI for 1-D cursor control using motor imagery and a passive BCI for 2-D cursor control. We show significant improvement across participants in both datasets compared to existing methods.

20.
Theriogenology ; 133: 38-44, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31055160

RESUMEN

This study was designed to compare the effects on goat spermatozoa cryosurvival of nano-lecithin-based (NL), lecithin-based (L) and egg yolk-based (EY) extenders. Ejaculates were collected from four fertile goats using artificial vagina and diluted with nine extenders. NL and L were tested at concentrations 1%, 2%, 3% and 4% (w/v), versus 15% (v/v) egg yolk-based extender. Overall, sperm quality (higher motility, viability and HOST, and lower apoptosis) was higher for NL than for L treatments (P < 0.05 for most cases, except for 1%). NL at 1% and especially at 4% showed lower motility and viability than 2% or 3% NL. NL at 2% achieved a better performance (P < 0.05) than EY for VCL (131.5 ±â€¯1.3 vs. 120.3 ±â€¯1.9 µm/s), VSL (43.9 ±â€¯1.5 vs. 35.8 ±â€¯1.4 µm/s), LIN (35.7 ±â€¯0.6 vs. 29.3 ±â€¯0.8%), WOB (47.0 ±â€¯0.5 vs. 43.9 ±â€¯0.9%) and viability (66.4 ±â€¯1.7 vs. 52.7 ±â€¯1.9%). Late apoptotic spermatozoa were also lower in 2% NL compared to EY (16.0 ±â€¯0.5 vs. 26.3 ±â€¯1.1%, P < 0.001). EY and 2% NL were compared in an IVF trial, with no significant differences in cleavage (68.8 vs. 70.8%) or blastocyst ratios (21.3 vs. 20.8%). In conclusion, using 2% nanolecithin in semen dilution could improve sperm cryosurvival of goat.


Asunto(s)
Cabras/fisiología , Lecitinas/farmacología , Preservación de Semen/veterinaria , Animales , Criopreservación/métodos , Criopreservación/veterinaria , Masculino , Nanopartículas , Preservación de Semen/métodos , Motilidad Espermática
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