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1.
Phys Chem Chem Phys ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958556

RESUMEN

The present investigation fits the reaction kinetics of a lithium-sulfur (Li-S) battery with polar electrolyte employing a novel two-phase continuum multipore model. The continuum two-phase model considers processes in both the liquid electrolyte phase and the solid precipitates phase, where the diffusion coefficients of the Li+ ions in a solvent-softened solid state are determined from molecular dynamics simulations. Solubility experiments yield the saturation concentration of sulfur and lithium sulfides in the polar electrolyte employed in this study. The model describes the transport of dissolved molecular and ion species in pores of different size in solvated or desolvated form, depending on pore size. The Li-S reaction model in this study is validated for electrolyte 1 M LiPF6 in EC/DMC. It includes seven redox reactions and two cyclic non-electrochemical reactions in the cathode, and the lithium redox reaction at the anode. Electrochemical reactions are assumed to take place in the electrolyte solution or the solid state and cyclic reactions are assumed to take place in the liquid electrolyte phase only. The determination of the reaction kinetics parameters takes place via fitting the model predictions with experimental data of a cyclic voltammetry cycle with in operando UV-vis spectroscopy.

2.
J Chem Phys ; 158(6): 064702, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36792496

RESUMEN

In this study, we monitor the dissolution of sulfur and sulfides in electrolyte solvents for lithium-sulfur (Li-S) and sodium-sulfur (Na-S) batteries. The first aim of this research is to assemble a comprehensive set of data on solubilities and dissolution kinetics that may be used in the simulation of battery cycling. The investigation also offers important insights to address key bottlenecks in the development and commercialization of metal-sulfur batteries, including the incomplete dissolution of sulfur in discharge and insoluble low-order sulfides in charge, the probability of shuttling of soluble polysulfides, and the pausing of the redox reactions in precipitated low order sulfides depending on their degree of solid state. The tested materials include sulfur, lithium sulfides Li2Sx, x = 1, 2, 4, 6, and 8, and sodium sulfides Na2Sx, x = 1, 2, 3, 4, 6, and 8, dissolved in two alternative electrolyte solvents: DOL:DME 1:1 v/v and TEGDME. The determined properties of the solute dissolution in the solvent include saturation concentration, mass transfer coefficient, and diffusion coefficient of the solvent in the solid solute. In general, the DOL:DME system offers high solubility in Li-S batteries and TEGDME offers the highest solubility in Na-S batteries. Low solubility sulfides are Li2S2 and Li2S for the Li-S batteries, and Na2S3, Na2S2, and Na2S for the Na-S batteries. However, it is noted that Na2S3 dissolves fast in TEGDME and also TEGDME diffuses fast into Na2S3, offering the possibility of a swollen Na2S3 structure in which Na+ ions might diffuse and continue the redox reactions in a semisolid state.

3.
Molecules ; 28(15)2023 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-37570657

RESUMEN

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) has been shown to enhance fingermark recovery compared to standard processes used by police forces, but there is no data to show how generally applicable the improvement is. Additionally, ToF-SIMS can be run in either positive or negative ion mode (or both), and there is no data on which mode of operation is most effective at revealing fingerprints. This study aims to fill these gaps by using ToF-SIMS to image fingerprints deposited on two common exhibit-type surfaces (polyethylene and stainless steel) using 10 donors and ageing fingerprints in either ambient, rainwater, or underground for 1 and 5 months. In all, 120 fingerprints were imaged using ToF-SIMS, and each was run in positive and negative modes. A fingerprint expert compared the fingerprint ridge detail produced by the standard process to the ToF-SIMS images. In over 50% of the samples, ToF-SIMS was shown to improve fingerprint ridge detail visualised by the respective standard process for all surfaces tested. In over 90% of the samples, the ridge detail produced by ToF-SIMS was equivalent to standard development across all different ageing and exposure conditions. The data shows that there is a benefit to running the ToF-SIMS in both positive and negative modes, even if no ridge detail was seen in one mode.

4.
Educ Inf Technol (Dordr) ; : 1-18, 2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36714439

RESUMEN

Evaluating the effectiveness of teaching methods for synchronous online instruction is integral to fostering student engagement and maximizing student learning, particularly in one-time workshops or seminars. Using the lens of social constructivism theory, this study investigated the effect of different approaches of synchronous online instruction on the development of graduate students' research data management (RDM) skills during the post-pandemic era. One experimental group received teacher-centered instruction primarily via lecture and the second experimental group received student-centered instruction with active learning activities. A one-way ANCOVA was used to compare the post-test RDM scores between one control group and the two experimental groups, while controlling for the impact of their pre-test RDM scores. Both experimental groups who received online RDM instruction scored higher than participants from the control group who received no instruction. Additionally, our results indicated that learners who were exposed to more engaged and collaborative instruction demonstrated higher learning outcomes than students who received teacher-centered instruction. These findings suggest that interactive teaching that actively engages the audience is essential for successful synchronous online learning. Simply transferring a lecture-based approach to online teaching will not result in optimal student engagement and learning. The interactive online instructional strategies used in this study (e.g., collective note-taking, Google Jamboard activities) can be applied to any instructional content to engage learners and enhance student learning.

5.
Reprod Domest Anim ; 56(6): 915-927, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33794028

RESUMEN

The aim of this study was to compare measurements of spermatozoal membrane status in dogs using computer-assisted spermatozoal quantification (CASQ) after staining with SYBR-14 and propidium iodide (PI) with manual counting after CFDA/PI staining. CASQ was performed on fresh (n = 11) and thawed cryopreserved canine semen (n = 91) using (1) a red long-pass (LP) filter on an untreated sample (membrane-disrupted spermatozoa, MDS count) and in a sample with all cellular membranes disrupted (total spermatozoal count, TC), (2) green LP filter for a TC and the red filter for an MDS count and (3) a green short-pass filter to obtain a membrane-intact spermatozoa (MIS) count and the red filter to obtain the MDS count, which were added to give a TC (red-green filter CASQ, n = 50). Spermatozoa were also stained with CFDA/PI, manually examined and classified as MIS or MDS. All measurements were performed in duplicate. The percentage of membrane-intact spermatozoa (MIS) was calculated. The percentage of progressively motile spermatozoa (PMS) was determined subjectively. The data were analysed to measure the agreement between the CASQ and CFDA/PI methods, repeatability of the methods and correlation between the MIS and PMS percentage. Compared with the CFDA/PI method, the agreement of MIS percentage with red filter CASQ was -12% to 34%, green LP filter CASQ -42% to 47% and red-green filter CASQ -23% to 29%. The repeatability of the CFDA/PI and red-green filter CASQ methods were the highest. The MIS and PMS percentages were always correlated (p < .05). Measurement of MIS percentage using red and red-green filter CASQ appeared to be the most reliable automated methods.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Análisis de Semen/veterinaria , Espermatozoides/citología , Animales , Membrana Celular , Perros , Masculino , Microscopía Fluorescente/veterinaria , Compuestos Orgánicos , Propidio , Coloración y Etiquetado/métodos , Coloración y Etiquetado/veterinaria
6.
Reprod Domest Anim ; 56(1): 89-102, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33135240

RESUMEN

The aim of this study was to evaluate the use of SYBR-14/propidium iodide (PI) stain in a computer-assisted spermatozoal quantification (CASQ) method of determining spermatozoal concentration in canine semen. In Experiment A, the spermatozoal concentration was measured (n = 52) with a haemocytometer and by CASQ under fluorescent illumination using green long-pass (G-LP) and red long-pass filters at measurement concentrations of <25 million/ml. For the red filter, the limits of agreement between the haemocytometer and CASQ were -6.3% to 6.8% and -7.5% to 6.2% between the haemocytometer and CASQ for the G-LP filter. For the red filter, the mean precision CVs were 2.21% ± 4.33% (mean ± 95% CI) for the haemocytometer, 2.19% ± 4.29% for CASQ and using the G-LP filter 2.13% ± 4.18% for the haemocytometer and 2.66% ± 5.21% for CASQ. In Experiment B, spermatozoa were also examined with a green spectrum short-pass (G-SP) filter (n = 50) at measurement concentrations of <12.5 million/ml. The limits of agreement between the haemocytometer and CASQ were -5.4% to 7.8% using the red filter, -15.8% to 14.3% using the G-LP filter and -13.1% to 11.3% using the G-SP filter. The mean precision CVs for the haemocytometer and CASQ, respectively, were 2.68% ± 5.26% (mean ± 95% CI) and 1.93% ± 3.72% using the red filter and 2.01% ± 3.95% and 3.55% ± 6.95% using the G-LP filter, and 3.96% ± 7.76% for CASQ using the G-SP filter. Using the red filter, the agreement between the haemocytometer and CASQ and the precision of both haemocytometer methods and CASQ were better than when using green filters. The CASQ method performed using green filters produced acceptable results; however, CASQ using a red filter with PI staining alone was superior to that using green filters and SYBR-14/PI staining.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Análisis de Semen/veterinaria , Recuento de Espermatozoides/veterinaria , Animales , Perros , Masculino , Microscopía Fluorescente/veterinaria , Compuestos Orgánicos , Propidio , Análisis de Semen/métodos , Recuento de Espermatozoides/métodos , Espermatozoides , Coloración y Etiquetado/métodos , Coloración y Etiquetado/veterinaria
7.
Reprod Domest Anim ; 54(12): 1583-1595, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31545547

RESUMEN

The aim of this study was to compare measurement of spermatozoal membrane status using computer-assisted spermatozoal quantification (CASQ) and eosin-nigrosin (EN) staining with manual counting after CFDA/PI staining. Analysis was performed on both fresh and thawed cryopreserved canine semen. Membrane-disrupted spermatozoa (MDS) were counted using CASQ (n = 311) in an untreated sample and a completely membrane-disrupted sample, and the percentage of membrane-intact spermatozoa (MIS) calculated: (Total count - Untreated sample count) ÷ Total count × 100. Spermatozoa were stained with a one-step EN stain (n = 501), and then, at least 100 spermatozoa were manually examined under ×1,000 magnification and classified as MDS (stained with eosin) or MIS (non-stained). Spermatozoa from the same samples were also stained with CFDA/PI, and then, at least 200 spermatozoa were manually examined under ×1,000 magnification and classified as MIS (completely stained by CFDA) or MDS. The percentage of progressively motile spermatozoa (PMS) was determined by both computer-assisted semen analysis (CASA) and subjective methodologies, and the data were subsequently analysed to measure the agreement between the CASQ and EN methods with the CFDA/PI technique using Bland-Altman methodology. Pearson's correlation was measured between the MIS and PMS percentage samples and correlation coefficients compared. The mean MIS percentage was lower for CASQ and higher for EN than in CFDA/PI for all comparisons. The agreement of MIS percentage between CASQ and CFDA/PI was -20.2% to 32.0%, and between EN and CFDA/PI was -32.9% to 14.9%. In all methods, the MIS and PMS percentages were correlated (p < .001). Measurement of CFDA/PI appeared to be the most reliable and accurate method of determining MIS percentage in dogs. Further investigation is required to determine whether the CASQ technique can be improved. Eosin-nigrosin staining also appeared to be unreliable at MIS <80% and overestimated the MIS percentage.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Microscopía Fluorescente/veterinaria , Análisis de Semen/veterinaria , Recuento de Espermatozoides/veterinaria , Animales , Criopreservación/veterinaria , Perros , Masculino , Microscopía Fluorescente/métodos , Preservación de Semen/veterinaria , Recuento de Espermatozoides/métodos , Espermatozoides , Coloración y Etiquetado
8.
Reprod Domest Anim ; 54(11): 1477-1488, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31441976

RESUMEN

The aim of this study was to develop and validate a novel, computer-assisted spermatozoal quantification (CASQ) method of determining spermatozoal concentration in canine semen. In Experiment A, the spermatozoal concentration was measured (n = 28) with a haemocytometer using light microscopy, CASQ and computer-assisted semen analysis (CASA; MMC sperm), following three independent dilutions. The limits of agreement between the haemocytometer and CASQ were -13.1% to 13.8% and -27.0% to 28.6% between the haemocytometer and CASA. The precision CVs (limits of agreement) were 5.7% (-7.8% to 8.9%) for the haemocytometer, 6.2% (-8.8% to 12.3%) for CASQ and 10.8% (-16.0% to 19.5%) for CASA. In Experiment B, spermatozoa were manually counted (n = 42) with the haemocytometer under fluorescent illumination using the CASQ sample. The limits of agreement between the CASQ and the haemocytometer were satisfactory (-4.6% to 4.6%) and the precision CVs (limits of agreement) were 6.2% (-9.0% to 11.4%) for the haemocytometer and 4.4% (-5.8% to 8.6%) for CASQ. The CASQ method was then clinically applied to compare the haemocytometer (light and fluorescent methods) with CASQ and CASA. Outlying data were removed. These studies demonstrated that CASQ was reliable and that the MMC sperm CASA was unreliable as methods for determining spermatozoal concentration in canine semen. Computer-assisted spermatozoal quantification was also determined to be more precise than manual counting with the haemocytometer. Using the clinical protocol, the agreement between the haemocytometer and CASQ method was acceptable, but it was worse than in the experiments where duplicate samples and a larger volume of semen were analysed. The CASQ method may be a useful method to measure the membrane status of canine spermatozoa; however, further investigation is required. Counting spermatozoa using fluorescent microscopy and the haemocytometer may improve the efficiency of counting and the accuracy of the method.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Microscopía Fluorescente/veterinaria , Análisis de Semen/veterinaria , Recuento de Espermatozoides/veterinaria , Animales , Perros , Masculino , Microscopía Fluorescente/métodos , Recuento de Espermatozoides/métodos , Espermatozoides
9.
Sensors (Basel) ; 19(19)2019 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-31569329

RESUMEN

There is a growing desire for wearable sensors in health applications. Fibers are inherently flexible and as such can be used as the electrodes of flexible sensors. Fiber-based electrodes are an ideal format to allow incorporation into fabrics and clothing and for use in wearable devices. Electrically conducting fibers were produced from a dispersion of poly (3,4-ethylenedioxythiophene)-poly (styrenesulfonate) (PEDOT: PSS). Fibers were wet spun from two PEDOT: PSS sources, in three fiber diameters. The effect of three different chemical treatments on the fibers were investigated and compared. Short 5 min treatment times with dimethyl sulfoxide (DMSO) on 20 µm fibers produced from Clevios PH1000 were found to produce the best overall treatment. Up to a six-fold increase in electrical conductivity was achieved, reaching 800 S cm-1, with no loss of mechanical strength (150 MPa). With a pH-sensitive polyaniline coating, these fibers displayed a Nernstian response across a pH range of 3.0 to 7.0, which covers the physiologically critical pH range for skin. These results provide opportunities for future wearable, fiber-based sensors including real-time, on-body pH sensing to monitor skin disease.


Asunto(s)
Técnicas Electroquímicas/instrumentación , Electrodos , Poliestirenos/química , Solventes/química , Tiofenos/química , Dispositivos Electrónicos Vestibles , Dimetilsulfóxido/química , Conductividad Eléctrica , Técnicas Electroquímicas/métodos , Formiatos/química , Concentración de Iones de Hidrógeno , Espectrometría Raman , Ácidos Sulfúricos/química , Resistencia a la Tracción
10.
Anal Chem ; 90(6): 3936-3941, 2018 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-29488747

RESUMEN

This work presents a data analysis extension to a well-established methodology for the assessment of organic coatings using imaging time-of-flight secondary ion mass spectrometry (ToF-SIMS). Such an approach produced results that can be analyzed using a multivariate analysis (MVA) procedure that performs the simultaneous processing of spatially and chemically related datasets. The coatings consist of two commercial resins that yield extremely similar spectra, and there are no peaks of sufficient intensity that are uniquely diagnostic of either material to provide an unambiguous identification of each. In order to resolve the problem, in addition to microtome-based sample preparation steps of tapers for the analysis through sample thickness, standard samples in cured and uncured conditions are introduced and measured in the same fashion as the specimens under investigation. The resulting ToF-SIMS imaging datasets have been processed using non-negative matrix factorization (NMF), which enabled identification of phase separation in the cured coatings.

11.
J Med Libr Assoc ; 106(1): 108-112, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29339940

RESUMEN

OBJECTIVE: This article describes the collection and analysis of annotated bibliographies created by first-year health sciences students to support their final poster projects. The authors examined the students' abilities to select relevant and authoritative sources, summarize the content of those sources, and correctly cite those sources. METHODS: We collected images of 1,253 posters, of which 120 were sampled for analysis, and scored the posters using a 4-point rubric to evaluate the students' information literacy skills. RESULTS: We found that 52% of students were proficient at selecting relevant sources that directly contributed to the themes, topics, or debates presented in their final poster projects, and 64% of students did well with selecting authoritative peer-reviewed scholarly sources related to their topics. However, 45% of students showed difficulty in correctly applying American Psychological Association (APA) citation style. CONCLUSION: Our findings demonstrate a need for instructors and librarians to provide strategies for reading and comprehending scholarly articles in addition to properly using APA citation style.


Asunto(s)
Alfabetización Informacional , Carteles como Asunto , Competencia Profesional , Estudiantes del Área de la Salud , Adulto , Bibliografías como Asunto , Evaluación Educacional , Femenino , Humanos , Masculino , Nevada , Adulto Joven
12.
Paediatr Child Health ; 28(7): 397-398, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37885604
14.
J Head Trauma Rehabil ; 30(2): 136-42, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-24590151

RESUMEN

OBJECTIVE: To examine the comparative efficacy of 3 common measures of traumatic brain injury (TBI) severity for predicting inpatient outcomes upon hospital discharge. SETTING: Acute brain injury rehabilitation unit at level 1 trauma center. PARTICIPANTS: 100 patients with TBI. DESIGN: Retrospective analysis of injury severity, demographic, and outcome data. MAIN MEASURES: Glasgow Coma Scale (GCS) at admission, time to follow commands (TTC), duration of posttraumatic amnesia (PTA), and Functional Independence Measure at hospital discharge. RESULTS: A hierarchal multiple regression revealed that duration of PTA was a significant and powerful unique predictor of Functional Independence Measure scores at discharge (ß = -0.46, P = .001), while TTC (ß = 0.26, P = .056) and GCS (ß = 0.16, P = .143) were not. These effects were present even after controlling for age, gender, educational level, racial/ethnic minority status, cause of injury, history of substance abuse, and neurosurgical intervention. CONCLUSION: Although clinicians often use GCS scores and TTC when assessing acute TBI severity and during treatment formulation, this study provides evidence that duration of PTA may be a more meaningful predictor of patients' functional levels at discharge.


Asunto(s)
Lesiones Encefálicas/rehabilitación , Adulto , Lesiones Encefálicas/complicaciones , Lesiones Encefálicas/psicología , Femenino , Escala de Coma de Glasgow , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Recuperación de la Función , Estudios Retrospectivos , Factores Socioeconómicos , Resultado del Tratamiento , Adulto Joven
15.
16.
Sci Total Environ ; 921: 170950, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38360301

RESUMEN

The study investigated inter-species variation in particulate matter (PM) accumulation, wash-off, and retention on green wall plants, with a focus on leaf characteristics. Ten broadleaf plant species were studied in an experimental green wall. Ambient PM concentrations remained relatively stable throughout the measurement period: PM1: 16.60 ± 9.97 µgm-3, PM2.5: 23.27 ± 11.88 µgm-3, and PM10: 39.59 ± 25.72 µgm-3. Leaf samples were taken before and after three rainfall events, and PM deposition was measured using Scanning Electron Microscopy (SEM). Leaf micromorphological traits, including surface roughness, hair density, and stomatal density, exhibited variability among species and leaf surfaces. Notably, I.sempervirens and H.helix had relatively high PM densities across all size fractions. The study underscored the substantial potential of green wall plants for atmospheric PM removal, with higher Wall Leaf Area Index (WLAI) species like A.maritima and T.serpyllum exhibiting increased PM accumulation at plant level. Rainfall led to significant wash-off for smaller particles, whereas larger particles exhibited lower wash-off rates. Leaf micromorphology impacted PM accumulation, although effects varied among species, and parameters such as surface roughness, stomatal density, and leaf size did not consistently affect PM deposition. The composition of deposited particles encompassed natural, vehicular, salt, and unclassified agglomerates, with minimal changes after rainfall. Air Pollution Tolerance Index (APTI) assessments revealed that I.sempervirens displayed the highest air pollution tolerance, while O.vulgare had the lowest. APTI showed a moderate positive correlation with PM deposition across all fractions. The study concluded that the interplay of macro and micromorphology in green wall plant species determines their PM removal potential. Further research is needed to identify the key leaf characteristics for optimal green wall species selection for effective PM removal.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Plantas , Hojas de la Planta/química , Árboles
17.
Sci Total Environ ; 914: 169713, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38163588

RESUMEN

This study investigated influences of leaf traits on particulate matter (PM) wash-off and (re)capture (i.e., net removal) over time. Leaf samples were taken before and after three rainfall events from a range of 10 evergreen woody plants (including five different leaf types), which were positioned with an optical particle counter alongside a busy road. Scanning electron microscopy was used to quantify the density (no./mm2), mass (µg/cm2), and elemental composition of deposited particles. To enable leaf area comparison between scale-like leaves and other leaf types, a novel metric (FSA: foliage surface area per unit branch length) was developed, which may be utilised by future research. Vehicle-related particles constituted 15 % of total deposition, and there was a notable 50 % decrease in the proportion of tyre wear particles after rainfall. T. baccata presented the lowest proportion (11.1 %) of vehicle-related particle deposition but the most consistent performance in terms of net PM removal. Only four of the 10 plant specimens (C. japonica, C. lawsoniana, J. chinensis, and T. baccata) presented effective PM wash-off across all particle size fractions and rainfall intensities, with a generally positive relationship observed between rainfall intensity and wash-off. Mass deposition was more significantly determined by particle size than number density. Interestingly, larger particles were also less easily washed off than smaller particles. Some traits typically considered to be advantageous (e.g., greater hairiness) may in fact hinder net removal over time due to retention under rainfall. Small leaf area is one trait that may promote both accumulation and wash-off. However, FSA was found to be the most influential trait, with an inverse relationship between FSA and wash-off efficacy. This finding poses trade-offs and opportunities for green infrastructure design, which are discussed. Finally, numerous areas for future research are recommended, underlining the importance of systems approaches in developing vegetation management frameworks.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminación por Tráfico Vehicular , Material Particulado/análisis , Plantas , Tamaño de la Partícula , Hojas de la Planta/química , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Árboles
18.
Small Methods ; 8(2): e2300223, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37330642

RESUMEN

Perovskite solar cells (PSCs) have shown rapid development recently, whereas nonideal stability remains the chief obstacle toward commercialization. Thus, it is of utmost importance to probe the degradation pathway for the entire device. Here, the extrinsic stability of inverted PSCs (IPSCs) is investigated by using standard shelf-life testing based on the International Summit on Organic Photovoltaic Stability protocols (ISOS-D-1). During the long-term assessment of 1700 h, the degraded power conversion efficiency is mainly caused by the fill factor (53% retention) and short-circuit current density (71% retention), while the open-circuit voltage still maintains 97% of the initial values. Further absorbance evolution and density functional theory calculations disclose that the perovskite rear-contact side, in particular for the perovskite/fullerene interface, is the predominant degradation pathway. This study contributes to understanding the aging mechanism and enhancing the durability of IPSCs for future applications.

19.
Pulm Pharmacol Ther ; 26(2): 205-11, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23142020

RESUMEN

Pulmonary embolism (PE) increases pulmonary vascular resistance, causing right ventricular (RV) dysfunction, and poor clinical outcome. Present studies test if the soluble guanylate cyclase stimulator BAY 41-8543 reduces pulmonary vascular resistance and protects RV function. Experimental PE was induced in anesthetized, male Sprague-Dawley rats by infusing 25 µm polystyrene microspheres (1.95 million/100 g body wt, right jugular vein) producing moderate PE. Pulmonary artery vascular resistance, estimated as RVPSP/CO, increased 3-fold after 5 h of PE. Treatment with BAY 41-8543 (50 µg/kg, I.V.; given at the time of PE induction) normalized this index by reducing RVPSP and markedly increasing CO, via preservation of heart rate and stroke volume. Ex vivo RV heart function showed minimal changes at 5 h of PE, but decreased significantly after 18 h of PE, including peak systolic pressure (PSP, Control 39 ± 1 mmHg vs. 19 ± 3 PE), +dP/dt (1192 ± 93 mmHg/s vs. 444 ± 64) and -dP/dt (-576 ± 60 mmHg/s vs. -278 ± 40). BAY 41-8543 significantly improved all three indices of RV heart function (PSP 35 ± 3.5, +dP/dt 1129 ± 100, -dP/dt -568 ± 87). Experimental PE produced increased PVR and RV dysfunction, which were ameliorated by treatment with BAY 41-8543. Thus, there is vasodilator reserve in this model of experimental PE that can be exploited to reduce the stress upon the heart and preserve RV contractile function.


Asunto(s)
Morfolinas/uso terapéutico , Embolia Pulmonar/tratamiento farmacológico , Pirimidinas/uso terapéutico , Función Ventricular Derecha/efectos de los fármacos , Animales , Hemodinámica/efectos de los fármacos , Masculino , Derrame Pleural/tratamiento farmacológico , Embolia Pulmonar/fisiopatología , Ratas , Ratas Sprague-Dawley , Troponina I/sangre
20.
Sci Justice ; 63(1): 9-18, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36631186

RESUMEN

The processes routinely used by police forces to visualise fingermarks in casework may not provide sufficient ridge pattern quality to aid an investigation. Time of Flight-Secondary Ion Mass Spectrometry (ToF-SIMS) has been proposed as a technique to enhance fingermark recovery. The technique is currently designated a Category C process in the Fingermark Visualisation Manual (FVM) as it shows potential for effective fingermark visualisation but has not yet been fully evaluated. Here the sensitivity of ToF-SIMS on three common exhibit-type surfaces - paper, polyethylene and stainless-steel was compared to standard processes. An adapted Home Office grading scale was used to evaluate the efficacy of fingerprint development by ToF-SIMS and to provide a framework for comparison with standard processes. ToF-SIMS was shown to visualise more fingerprints than the respective standard process, for all surfaces tested. In addition, ToF-SIMS was applied after the standard processes and successfully enhanced the fingerprint detail, even when the standard process failed to visualise ridge detail. This demonstrates the benefit for incorporating it into current operational fingermark development workflows. Multivariate analysis (MVA), using simsMVA, was additionally explored as a method to simplify the data analysis and image generation process.


Asunto(s)
Dermatoglifia , Espectrometría de Masa de Ion Secundario , Humanos , Espectrometría de Masa de Ion Secundario/métodos , Policia , Análisis Multivariante
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