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1.
J Am Chem Soc ; 145(9): 5553-5560, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36848549

RESUMEN

Carbodiimide-fueled anhydride bond formation has been used to enhance the mechanical properties of permanently crosslinked polymer networks, giving materials that exhibit transitions from soft gels to covalently reinforced gels, eventually returning to the original soft gels. Temporary changes in mechanical properties result from a transient network of anhydride crosslinks, which eventually dissipate by hydrolysis. Over an order of magnitude increase in the storage modulus is possible through carbodiimide fueling. The time-dependent mechanical properties can be modulated by the concentration of carbodiimide, temperature, and primary chain architecture. Because the materials remain rheological solids, new material functions such as temporally controlled adhesion and rewritable spatial patterns of mechanical properties have been realized.

2.
Ecol Evol ; 13(5): e10017, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37214620

RESUMEN

The history of the decline of the Ivory-billed Woodpecker is long and complex, but the status of the species since 1944, when the last widely accepted sighting in continental North America occurred, is particularly controversial. Reports of Ivory-billed Woodpeckers have continued, but none has reached the threshold of quality for general acceptance by ornithologists or the birdwatching public. In 2021, the U.S. Fish and Wildlife Service opened for public comment a proposal to declare the species extinct. Here, we present evidence suggesting the presence of the Ivory-billed Woodpecker at our study site, based on a variety of data collected over a 10-year search period, 2012-2022. These data are drawn from visual observations, ~70,000 h of recordings by 80-100 acoustic recording units, ~472,550 camera-hours by as many as 34 trail cameras, and ~1089 h of video drawn from ~3265 drone flights. Using multiple lines of evidence, the data suggest intermittent but repeated presence of multiple individual birds with field marks and behaviors consistent with those of Ivory-billed Woodpeckers. Data indicate repeated reuse of foraging sites and core habitat. Our findings, and the inferences drawn from them, suggest that not all is lost for the Ivory-billed Woodpecker, and that it is clearly premature for the species to be declared extinct.

3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 4635-4640, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-36085899

RESUMEN

In this paper, we explore the use of the 4D discrete wavelet transform (DWT) on fMRI data. The data set comes from a study on schizophrenia. The compact support of the wavelet transform means that it keeps phenomenon localized in all 4 dimensions. We examine 16 sub-signals (frequency banded components of the signal) resulting from the 4D DWT, repre-senting the sub-signals as energy fluctuations over time. Next, we correlate these, and examine the variance. We find that grouping the variance data shows a small but clear trend of the control group versus those with a schizophrenia diagnosis. The DWT analyzes a signal into approximations and details, which we expect reflect the similarities and differences between brain activity, respectively. We want to know how the regions of brain activity vary with time, and the high-pass data encodes these changes over time.


Asunto(s)
Esquizofrenia , Análisis de Ondículas , Citoplasma , Humanos , Imagen por Resonancia Magnética , Esquizofrenia/diagnóstico por imagen , Coloración y Etiquetado
4.
Water Res ; 41(12): 2690-6, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17493659

RESUMEN

Granular activated carbon (GAC) adsorbers are often the penultimate stage of surface water treatment and provide ideal habitats for invertebrates. Proliferation of chlorine-resistant invertebrates in GAC adsorbers may lead to their efflux into distribution systems, possibly resulting in contamination of customers' tap water. GAC adsorber sampling and laboratory experiments were undertaken to determine the effects of routine backwashing on GAC adsorber populations of the chlorine-resistant snail Potamopyrgus jenkinsi at a water treatment works. GAC adsorber sampling results suggested that routine backwashing altered the spatial distribution of snails, but not their overall abundance. In small-scale glass columns 40-50% of the smallest (0.3-0.6 mm shell height) juvenile snails were removed by a GAC backwash bed expansion of 30-40%; however, bed expansions of greater than 20% were not possible in the GAC adsorbers.


Asunto(s)
Caracoles , Purificación del Agua/métodos , Adsorción , Animales , Carbono/química , Densidad de Población , Purificación del Agua/instrumentación
5.
Neuroinformatics ; 14(1): 23-40, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26306864

RESUMEN

The CARMEN Virtual Laboratory (VL) is a cloud-based platform which allows neuroscientists to store, share, develop, execute, reproduce and publicise their work. This paper describes new functionality in the CARMEN VL: an interactive publications repository. This new facility allows users to link data and software to publications. This enables other users to examine data and software associated with the publication and execute the associated software within the VL using the same data as the authors used in the publication. The cloud-based architecture and SaaS (Software as a Service) framework allows vast data sets to be uploaded and analysed using software services. Thus, this new interactive publications facility allows others to build on research results through reuse. This aligns with recent developments by funding agencies, institutions, and publishers with a move to open access research. Open access provides reproducibility and verification of research resources and results. Publications and their associated data and software will be assured of long-term preservation and curation in the repository. Further, analysing research data and the evaluations described in publications frequently requires a number of execution stages many of which are iterative. The VL provides a scientific workflow environment to combine software services into a processing tree. These workflows can also be associated with publications and executed by users. The VL also provides a secure environment where users can decide the access rights for each resource to ensure copyright and privacy restrictions are met.


Asunto(s)
Almacenamiento y Recuperación de la Información/métodos , Neurociencias , Publicaciones Periódicas como Asunto , Nube Computacional , Humanos , Difusión de la Información , Internet , Reproducibilidad de los Resultados , Programas Informáticos
6.
Acad Radiol ; 22(9): 1128-37, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26036721

RESUMEN

RATIONALE AND OBJECTIVES: Coronary artery calcium (CAC) images can be reconstructed with thinner slice thickness on some modern multidetector-row computed tomography scanners without additional radiation. We hypothesized that the isotropic 0.5-mm CAC reconstruction outperforms the conventional 3.0-mm reconstruction in detecting and quantifying coronary calcium, and we proposed to compare them by validating against spatially registered intravascular ultrasound with radiofrequency backscatter-virtual histology (IVUS-VH). MATERIALS AND METHODS: Twenty-seven patients were enrolled, and 5976 mm of coronary arteries were analyzed. A semiautomatic software was developed to coregister CAC and IVUS-VH on a detailed slice-by-slice basis. Calcium detection and calcium volume quantification were evaluated and compared using varying calcium attenuation thresholds. Algorithms for deriving individualized optimal threshold and comparable Agatston score on the 0.5-mm reconstruction were developed. RESULTS: The isotropic 0.5-mm reconstruction achieved significantly higher area under receiver-operating curve than the conventional 3.0-mm reconstruction (0.9 vs. 0.74, P < .001). Using the optimal threshold, the 0.5-mm reconstruction had higher sensitivity (0.79 vs. 0.65), specificity (0.85 vs. 0.77), positive predictive value (0.42 vs. 0.29), and negative predictive value (0.97 vs. 0.94) than the 3.0 mm. Individualized optimal threshold was significantly correlated with the image noise (r = 0.66, P < .001) in the 0.5-mm reconstruction. CONCLUSIONS: By optimizing the calcium threshold, the 0.5-mm reconstruction is superior to the conventional 3.0-mm in detecting and quantifying calcium, which may improve the clinical value of CAC without additional radiation.


Asunto(s)
Calcio/análisis , Angiografía Coronaria/estadística & datos numéricos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Tomografía Computarizada Multidetector/estadística & datos numéricos , Adulto , Anciano , Algoritmos , Área Bajo la Curva , Femenino , Humanos , Masculino , Persona de Mediana Edad , Placa Aterosclerótica/diagnóstico por imagen , Valor Predictivo de las Pruebas , Estudios Prospectivos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Dispersión de Radiación , Sensibilidad y Especificidad , Ultrasonografía Intervencional/estadística & datos numéricos , Interfaz Usuario-Computador
7.
J Leukoc Biol ; 97(3): 573-82, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25583578

RESUMEN

MDSCs are a heterogeneous group of myeloid cells that suppress T cell activity in cancer and autoimmune disease. The effect of MDSCs on B cell function is not clear. Using the CIA model of autoimmune disease, we found an increase in M-MDSCs in the periphery of WT mice with CIA compared with naïve mice. These MDSCs were absent from the periphery of CCR2(-/-) mice that developed exacerbated disease. M-MDSCs, isolated from immunized mice, inhibited autologous CD4(+) T cell proliferation. The M-MDSC-mediated suppression of T cell proliferation was NO and IFN-γ dependent but IL-17 independent. Furthermore, we demonstrated for the first time that M-MDSCs from CIA mice also inhibited autologous B cell proliferation and antibody production. The suppression of B cells by M-MDSCs was dependent on the production of NO and PGE2 and required cell-cell contact. Administration of M-MDSCs rescued CCR2(-/-) mice from the exacerbated CIA phenotype and ameliorated disease in WT mice. Furthermore, adoptive transfer of M-MDSCs reduced autoantibody production by CCR2(-/-) and WT mice. In summary, M-MDSCs inhibit T cell and B cell function in CIA and may serve as a therapeutic approach in the treatment of autoimmune arthritis.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Linfocitos B/inmunología , Células Mieloides/inmunología , Linfocitos T/inmunología , Animales , Formación de Anticuerpos/inmunología , Artritis Experimental/inmunología , Artritis Experimental/patología , Artritis Experimental/terapia , Enfermedades Autoinmunes/patología , Enfermedades Autoinmunes/terapia , Linfocitos T CD4-Positivos/inmunología , Proliferación Celular , Dinoprostona/metabolismo , Femenino , Inmunización , Interferón gamma/metabolismo , Interleucina-17/metabolismo , Masculino , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Monocitos/patología , Células Mieloides/trasplante , Óxido Nítrico Sintasa de Tipo II/metabolismo , Fenotipo , Receptores CCR2/deficiencia , Receptores CCR2/metabolismo
8.
J Am Acad Child Adolesc Psychiatry ; 43(1): 37-45, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14691359

RESUMEN

OBJECTIVE: To reduce the use of restraint and seclusion with children and adolescents in psychiatric inpatient units by promoting a preventive, strength-based model of care. METHOD: The State Mental Health Authority used data analysis, quality improvement strategies, regulatory oversight, and technical assistance to develop and implement system change over a 22-month period. No changes in regulation or policy were undertaken. RESULTS: Comparative data collected before and after the interventions demonstrated substantial reductions in the use of restraint and seclusion. Child units (age 5-12) decreased from 84.03 to 22.78 episodes per 1,000 patient days (72.9%), adolescent units from 72.22 to 37.99 episodes (47.4%), and mixed child/adolescent units from 73.37 to 30.08 episodes (59%). CONCLUSIONS: The use of restraint and seclusion in child and adolescent inpatient settings can be reduced through a systems approach, which may have applicability to other settings and systems.


Asunto(s)
Adolescente Hospitalizado , Niño Hospitalizado , Hospitales Psiquiátricos/tendencias , Hospitales Provinciales , Servicios de Salud Mental/tendencias , Aislamiento de Pacientes/estadística & datos numéricos , Restricción Física/estadística & datos numéricos , Adolescente , Psiquiatría del Adolescente/métodos , Actitud del Personal de Salud , Niño , Psiquiatría Infantil/métodos , Preescolar , Hospitales Psiquiátricos/estadística & datos numéricos , Humanos , Capacitación en Servicio , Massachusetts , Trastornos Mentales/terapia
9.
Gigascience ; 3(1): 3, 2014 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-24666584

RESUMEN

BACKGROUND: During early development, neural circuits fire spontaneously, generating activity episodes with complex spatiotemporal patterns. Recordings of spontaneous activity have been made in many parts of the nervous system over the last 25 years, reporting developmental changes in activity patterns and the effects of various genetic perturbations. RESULTS: We present a curated repository of multielectrode array recordings of spontaneous activity in developing mouse and ferret retina. The data have been annotated with minimal metadata and converted into HDF5. This paper describes the structure of the data, along with examples of reproducible research using these data files. We also demonstrate how these data can be analysed in the CARMEN workflow system. This article is written as a literate programming document; all programs and data described here are freely available. CONCLUSIONS: 1. We hope this repository will lead to novel analysis of spontaneous activity recorded in different laboratories. 2. We encourage published data to be added to the repository. 3. This repository serves as an example of how multielectrode array recordings can be stored for long-term reuse.

10.
Biomed Sci Instrum ; 50: 68-76, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25405406

RESUMEN

Hepatic progenitor cells (HPCs) have regenerative properties that could aid the development of treatments for severe liver disease. To study how pressure influences HPC fate, a hydrostatic pressure-controlled cell culture chamber was developed. The design incorporates custom LabView scripting for enhanced pressure regulation and data acquisition. Pressure can be controlled within ±0.2mmHg. Continuous airflow permits gas exchange, and CO2 is maintained at 5%±0.2%. Applied pressures range from 5 to 20 mmHg, reflecting interstitial pressure conditions in healthy and diseased livers, respectively. Bipotential Murine Oval Liver (BMOL) cells, an HPC-like cell line, were cultured in the chamber to test for maintenance of cell viability, adequate CO2 regulation, and maintenance of adequate media volume over 24 hours. Cultured cells were exposed to 5 or 19 mmHg. After 24 hours, media pH was measured, viable cells were counted (Trypan Blue, n=3), and plates were weighed to assess fluid loss. The number of live cells cultured under pressure vs. control conditions was not statistically different (p>.05). The pH remained constant at 7.0 for all conditions, suggesting adequate gas exchange. Evaporation of media was minimal at 3.97%. Results indicate that the pressure chamber provides appropriate environmental conditions for future studies on HPC pressure sensitivity.

11.
Philos Trans A Math Phys Eng Sci ; 371(1983): 20120080, 2013 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-23230159

RESUMEN

The CARMEN platform allows neuroscientists to share data, metadata, services and workflows, and to execute these services and workflows remotely via a Web portal. This paper describes how we implemented a service-based infrastructure into the CARMEN Virtual Laboratory. A Software as a Service framework was developed to allow generic new and legacy code to be deployed as services on a heterogeneous execution framework. Users can submit analysis code typically written in Matlab, Python, C/C++ and R as non-interactive standalone command-line applications and wrap them as services in a form suitable for deployment on the platform. The CARMEN Service Builder tool enables neuroscientists to quickly wrap their analysis software for deployment to the CARMEN platform, as a service without knowledge of the service framework or the CARMEN system. A metadata schema describes each service in terms of both system and user requirements. The search functionality allows services to be quickly discovered from the many services available. Within the platform, services may be combined into more complicated analyses using the workflow tool. CARMEN and the service infrastructure are targeted towards the neuroscience community; however, it is a generic platform, and can be targeted towards any discipline.


Asunto(s)
Algoritmos , Minería de Datos/métodos , Bases de Datos Factuales , Difusión de la Información/métodos , Internet , Programas Informáticos , Interfaz Usuario-Computador
12.
Food Chem ; 141(4): 4081-6, 2013 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-23993588

RESUMEN

Milk is a complex colloidal system that responds to changes in temperature imposed during processing. Whilst much has been learned about the effects of temperature on milk, little is known about the dynamic response of casein micelles to changes in temperature. In this study, a comprehensive physico-chemical study of casein micelles in skim milk was performed between 10 and 40 °C. When fully equilibrated, the amount of soluble casein, soluble calcium and the pH of skim milk all decreased as a function of increasing temperature, whilst the hydration and volume fraction of the casein micelles decreased. The effect of temperature on casein micelle size, as determined by dynamic light scattering and differential centrifugation, was less straightforward. Real-time measurements of turbidity and pH were used to investigate the dynamics of the system during warming and cooling of milk in the range 10-40 °C. Changes in pH are indicative of changes to the mineral system and the turbidity is a measure of alterations to the casein micelles. The pH and turbidity showed that alterations to both the casein micelles and the mineral system occurred very rapidly on warming. However, whilst mineral re-equilibration occurred very rapidly on cooling, changes to the casein micelle structure continued after 40 min of measurement, returning to equilibrium after 16 h equilibration. Casein micelle structure and the mineral system of milk were both dependent on temperature in the range 10-40 °C. The dynamic response of the mineral system to changes in temperature appeared almost instantaneous whereas equilibration of casein was considerably slower, particularly upon cooling.


Asunto(s)
Caseínas/química , Animales , Bovinos , Concentración de Iones de Hidrógeno , Cinética , Micelas , Temperatura
13.
Artículo en Inglés | MEDLINE | ID: mdl-23367046

RESUMEN

3D Computed Tomography (CT) provides noninvasive, low-radiation method of coronary artery calcium (CAC) measurement. Conventional CAC images are acquired on multidetector-row CT scanners without contrast, and reconstructed with 3 mm slice thickness. The calcium volume is quantified by registering voxels with attenuation values greater than or equal to 130 Hounsfield Unit (HU). In isotropic CAC images with 0.5 mm slice thickness obtained from 320-detector row CT, the optimal value of attenuation cutoff threshold is unknown. In this paper we find the optimal cutoff threshold for calcium quantification in isotropic CT calcium scans by validating against registered intravascular ultrasound with radiofrequency backscatter (IVUS/VH). From the statistical analysis of calcium data obtained from the images of 9 patients we found a range of optimal thresholds and the conventional threshold of 130 HU was in the range. Further, the optimal values were different for individual patients.


Asunto(s)
Calcinosis/diagnóstico , Enfermedad de la Arteria Coronaria/diagnóstico , Interpretación de Imagen Asistida por Computador/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Técnica de Sustracción , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía Intervencional/métodos , Algoritmos , Calcinosis/complicaciones , Enfermedad de la Arteria Coronaria/complicaciones , Humanos , Ondas de Radio , Reproducibilidad de los Resultados , Dispersión de Radiación , Sensibilidad y Especificidad
14.
PLoS One ; 6(10): e25833, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21991368

RESUMEN

CCR2 is considered a proinflammatory mediator in many inflammatory diseases such as rheumatoid arthritis. However, mice lacking CCR2 develop exacerbated collagen-induced arthritis. To explore the underlying mechanism, we investigated whether autoimmune-associated Th17 cells were involved in the pathogenesis of the severe phenotype of autoimmune arthritis. We found that Th17 cells were expanded approximately 3-fold in the draining lymph nodes of immunized CCR2(-/-) mice compared to WT controls (p = 0.017), whereas the number of Th1 cells and regulatory T cells are similar between these two groups of mice. Consistently, levels of the Th17 cell cytokine IL-17A and Th17 cell-associated cytokines, IL-6 and IL-1ß were approximately 2-6-fold elevated in the serum and 22-28-fold increased in the arthritic joints in CCR2(-/-) mice compared to WT mice (p = 0.04, 0.0004, and 0.01 for IL-17, IL-6, and IL-1ß, respectively, in the serum and p = 0.009, 0.02, and 0.02 in the joints). Furthermore, type II collagen-specific antibodies were significantly increased, which was accompanied by B cell and neutrophil expansion in CCR2(-/-) mice. Finally, treatment with an anti-IL-17A antibody modestly reduced the disease severity in CCR2(-/-) mice. Therefore, we conclude that while we detect markedly enhanced Th17-cell responses in collagen-induced arthritis in CCR2-deficient mice and IL-17A blockade does have an ameliorating effect, factors additional to Th17 cells and IL-17A also contribute to the severe autoimmune arthritis seen in CCR2 deficiency. CCR2 may have a protective role in the pathogenesis of autoimmune arthritis. Our data that monocytes were missing from the spleen while remained abundant in the bone marrow and joints of immunized CCR2(-/-) mice suggest that there is a potential link between CCR2-expressing monocytes and Th17 cells during autoimmunity.


Asunto(s)
Artritis Experimental/inmunología , Enfermedades Autoinmunes/inmunología , Receptores CCR2/deficiencia , Células Th17/inmunología , Animales , Anticuerpos/farmacología , Anticuerpos/uso terapéutico , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/patología , Autoanticuerpos/inmunología , Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/patología , Linfocitos B/citología , Linfocitos B/efectos de los fármacos , Linfocitos B/inmunología , Médula Ósea/efectos de los fármacos , Médula Ósea/inmunología , Médula Ósea/patología , Proliferación Celular/efectos de los fármacos , Epítopos/inmunología , Inmunización , Interleucina-17/inmunología , Articulaciones/inmunología , Articulaciones/patología , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/patología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Monocitos/efectos de los fármacos , Monocitos/inmunología , Infiltración Neutrófila/efectos de los fármacos , Infiltración Neutrófila/inmunología , Neutrófilos/efectos de los fármacos , Neutrófilos/inmunología , Receptores CCR2/sangre , Células Th17/citología , Células Th17/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/inmunología
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