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1.
Artículo en Inglés | MEDLINE | ID: mdl-36381556

RESUMEN

3D morphable models (3DMMs) simultaneously reconstruct facial morphology, expression and pose from 2D images, and thus could be an invaluable tool for capturing and characterizing the face and facial behavior in early childhood. However, 3DMM fitting on infants is a largely unexplored problem. All publicly available 3DMMs are developed for adults, and it is unclear if and to what extent they can be used on videos of infants. In this paper, we compare five state-of-the-art 3DMM fitting methods on data from naturalistic infant-caregiver interactions. Results suggest that it is possible to produce consistent and subject-specific reconstructions of 3D shape identity from multiple frames, but not from a single frame. Qualitative evaluation highlights that facial regions with high texture variation, such as eyes, brows and mouth, are captured with higher accuracy compared to the rest of the face. Thus, even though a 3DMM developed for adults has significant limitations when reconstructing the morphology of the entire facial region of infants, applications that involve analysis of facial behavior can be feasible. Our encouraging results, combined with the unique ability of 3DMMs to disentangle two major sources of noise for expression analysis (i.e., identity bias and pose variations), motivate future research on using 3DMMs to measure the facial behavior of infants.

2.
Mol Autism ; 13(1): 28, 2022 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-35761377

RESUMEN

BACKGROUND: Canonical babbling-producing syllables with a mature consonant, full vowel, and smooth transition-is an important developmental milestone that typically occurs in the first year of life. Some studies indicate delayed or reduced canonical babbling in infants at high familial likelihood for autism spectrum disorder (ASD) or who later receive an ASD diagnosis, but evidence is mixed. More refined characterization of babbling in the first year of life in infants with high likelihood for ASD is needed. METHODS: Vocalizations produced at 6 and 12 months by infants (n = 267) taking part in a longitudinal study were coded for canonical and non-canonical syllables. Infants were categorized as low familial likelihood (LL), high familial likelihood diagnosed with ASD at 24 months (HL-ASD) or not diagnosed (HL-Neg). Language delay was assessed based on 24-month expressive and receptive language scores. Canonical babble ratio (CBR) was calculated by dividing the number of canonical syllables by the number of total syllables. Generalized linear (mixed) models were used to assess the relationship between group membership and CBR, controlling for site, sex, and maternal education. Logistic regression was used to assess whether canonical babbling ratios at 6 and 12 months predict 24-month diagnostic outcome. RESULTS: No diagnostic group differences in CBR were detected at 6 months, but HL-ASD infants produced significantly lower CBR than both the HL-Neg and LL groups at 12 months. HL-Neg infants with language delay also showed reduced CBR at 12 months. Neither 6- nor 12-month CBR was significant predictors of 24-month diagnostic outcome (ASD versus no ASD) in logistic regression. LIMITATIONS: Small numbers of vocalizations produced by infants at 6 months may limit the reliability of CBR estimates. It is not known if results generalize to infants who are not at high familial likelihood, or infants from more diverse racial and socioeconomic backgrounds. CONCLUSIONS: Lower canonical babbling ratios are apparent by the end of the first year of life in ASD regardless of later language delay, but are also observed for infants with later language delay without ASD. Canonical babbling may lack specificity as an early marker when used on its own.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Trastornos del Desarrollo del Lenguaje , Trastorno del Espectro Autista/diagnóstico , Humanos , Lactante , Trastornos del Desarrollo del Lenguaje/diagnóstico , Estudios Longitudinales , Reproducibilidad de los Resultados
3.
Rev Sci Instrum ; 90(2): 025101, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30831749

RESUMEN

Vertical electrical impedance (VEI) testing is a method that was developed specifically for quantifying the level of protection against chloride ingress in concrete bridge decks. A significant operational difficulty associated with VEI testing has been establishing the required rebar tap as a ground reference. As described in this work, the use of a large-area electrode (LAE) can potentially remove the need for a rebar tap and therefore significantly simplify and accelerate the VEI testing process. The specific objective of the research was to develop both theoretical and practical guidance for the design of an LAE for VEI testing. To investigate several variables that can affect the accuracy of VEI measurements obtained using an LAE connection, including various combinations of deck cover and water resistivity values, electrode separation distance, counter electrode (CE) effective area, and area ratio between the LAE and the CE, an analytical model (AM) and a finite-element model (FEM) were developed and validated with laboratory and field experiments. From the results of the AM and FEM simulations and the results of the laboratory and field experiments, LAE design considerations were developed for each of these variables that should allow proper implementation of a VEI measurement system using an LAE connection.

4.
Rev Sci Instrum ; 83(8): 085104, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22938329

RESUMEN

Corrosion is a pressing problem for aging concrete infrastructure, especially bridge decks. Because of its sensitivity to factors that affect corrosion of reinforcing steel in concrete, resistivity is an important structural health indicator for reinforced concrete structures. In this research, an instrument was developed to measure vertical impedance on concrete bridge decks. Measurements of vertical impedance on slabs prepared in the laboratory, on slabs removed from decommissioned bridge decks, and on an in-service bridge deck in the field demonstrate the utility of the new apparatus.

5.
Dig Dis Sci ; 55(9): 2537-44, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20635148

RESUMEN

BACKGROUND: The purposes of this study are: (1) to prospectively evaluate clinically relevant outcomes including sedation-related complications for endoscopic ultrasound (EUS) procedures performed with the use of propofol deep sedation administered by monitored anesthesia care (MAC), and (2) to compare these results with a historical case-control cohort of EUS procedures performed using moderate sedation provided by the gastrointestinal (GI) endoscopist. MATERIALS AND METHODS: Patients referred for EUS between January 1, 2001 and December 31, 2002 were enrolled. Complication rates for EUS using MAC sedation were observed and also compared with a historical case-control cohort of EUS patients who received meperidine/midazolam for moderate sedation, administered by the GI endoscopist. Logistic regression analysis was used to isolate possible predictors of complications. RESULTS: A total of 1,000 patients underwent EUS with propofol sedation during the period from January 1, 2001 through December 31, 2002 (mean age 64 years, 53% female). The distribution of EUS indications based on the primary area of interest was: 170 gastroduodenal, 92 anorectal, 508 pancreaticohepatobiliary, 183 esophageal, and 47 mediastinal. The primary endpoint of the study was development of sedation-related complications occurring during a performed procedure. A total of six patients experienced complications: duodenal perforation (one), hypotension (one), aspiration pneumonia (one), and apnea requiring endotracheal intubation (three). The complication rate with propofol was 0.60%, compared with 1% for the historical case-control (meperidine/midazolam moderate sedation) group. CONCLUSIONS: There does not appear to be a significant difference between complication rates for propofol deep sedation with MAC and meperidine/midazolam administered for moderate sedation.


Asunto(s)
Anestésicos Intravenosos/administración & dosificación , Sedación Consciente , Sedación Profunda , Endoscopía Gastrointestinal , Endosonografía , Hipnóticos y Sedantes/administración & dosificación , Meperidina/administración & dosificación , Midazolam/administración & dosificación , Propofol/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Anestésicos Intravenosos/efectos adversos , Estudios de Casos y Controles , Sedación Consciente/efectos adversos , Sedación Profunda/efectos adversos , Endoscopía Gastrointestinal/efectos adversos , Endosonografía/efectos adversos , Femenino , Humanos , Hipnóticos y Sedantes/efectos adversos , Modelos Logísticos , Masculino , Meperidina/efectos adversos , Midazolam/efectos adversos , Persona de Mediana Edad , Propofol/efectos adversos , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Resultado del Tratamiento
6.
West Indian med. j ; 50(3): 234-235, Sept. 2001.
Artículo en Inglés | LILACS | ID: lil-333364

RESUMEN

Vaginitis emphysematosa is an uncommon inflammatory condition that is aetiologically linked to trichomonal or gardnerella infection, and has been associated with immunosuppressive disorders. The disease does not have deleterious sequelae and resolves on treating the underlying infection. We describe a case in which the disease predominantly affected the cervix leading to an abnormal pap smear and colposcopic investigation.


Asunto(s)
Femenino , Humanos , Persona de Mediana Edad , Vaginitis , Frotis Vaginal , Vaginitis , Colposcopía
7.
Fresenius J Anal Chem ; 370(2-3): 234-40, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11451243

RESUMEN

The S mass fractions of coal SRMs 2682b, 2684b, and 2685b are certified by direct comparison with coal SRMs 2682a, 2684a, and 2685a, respectively, using high-temperature combustion analysis with infrared (IR) absorption detection. The S mass fractions of the "a" materials used for calibration were previously determined by means of isotope-dilution thermal-ionization mass spectrometry (ID-TIMS). Therefore, the comparisons performed with the combustion-IR absorption method establish direct traceability links to accurate and precise ID-TIMS measurements. The expanded uncertainties associated with the certified S mass fractions are of approximately the same magnitude as would be expected for the ID-TIMS methodology. An important aspect of these certifications is that each "b" material is essentially identical with the corresponding "a" material, because both were produced from the same bulk, homogenized coal. As a test of the efficacy of the new certification approach when calibrant and unknown are not identical, the S mass fraction of coal SRM 2683b has been determined by direct comparison to coal SRM 2683a. These two coals, which have both previously been analyzed with ID-TIMS, are different in terms of S content and other properties. Whereas the S mass fraction for SRM 2683b determined with the new methodology agrees statistically with the ID-TIMS value, there is reason for caution in such cases. In addition to the usefulness of the alternative approach for certification activities within NIST, this approach might also be an excellent way of establishing NIST traceability during the value assignment process for reference materials not issued by NIST. Further research is needed, however, to understand better the scope of applicability.

8.
Fresenius J Anal Chem ; 370(2-3): 259-63, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11451248

RESUMEN

Multielement analyses of environmental reference materials have been performed using existing certified reference materials (CRMs) as calibration standards for inductively coupled plasma-mass spectrometry. The analyses have been performed using a high-performance methodology that results in comparison measurement uncertainties that are significantly less than the uncertainties of the certified values of the calibration CRM. Consequently, the determined values have uncertainties that are very nearly equivalent to the uncertainties of the calibration CRM. Several uses of this calibration transfer are proposed, including, re-certification measurements of replacement CRMs, establishing traceability of one CRM to another, and demonstrating the equivalence of two CRMs. RM 8704, a river sediment, was analyzed using SRM 2704, Buffalo River Sediment, as the calibration standard. SRM 1632c, Trace Elements in Bituminous Coal, which is a replacement for SRM 1632b, was analyzed using SRM 1632b as the standard. SRM 1635, Trace Elements in Subbituminous Coal, was also analyzed using SRM 1632b as the standard.


Asunto(s)
Sedimentos Geológicos/análisis , Oligoelementos/análisis , Calibración , Carbón Mineral/análisis , Monitoreo del Ambiente/instrumentación , Monitoreo del Ambiente/normas , Agua Dulce , Espectrometría de Masas/métodos , Estándares de Referencia
9.
West Indian Med J ; 50(3): 234-5, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11769034

RESUMEN

Vaginitis emphysematosa is an uncommon inflammatory condition that is aetiologically linked to trichomonal or gardnerella infection, and has been associated with immunosuppressive disorders. The disease does not have deleterious sequelae and resolves on treating the underlying infection. We describe a case in which the disease predominantly affected the cervix leading to an abnormal pap smear and colposcopic investigation.


Asunto(s)
Prueba de Papanicolaou , Frotis Vaginal , Vaginitis/patología , Colposcopía , Femenino , Humanos , Persona de Mediana Edad , Vaginitis/diagnóstico
10.
J Res Natl Inst Stand Technol ; 105(4): 571-9, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-27551625

RESUMEN

The problem of determining a consensus value and its uncertainty from the results of multiple methods or laboratories is discussed. Desirable criteria of a solution are presented. A solution motivated by the ISO Guide to the Expression of Uncertainty in Measurement (ISO GUM) is introduced and applied in a detailed worked example. A Bayesian hierarchical model motivated by the proposed solution is presented and compared to the solution.

12.
Am J Ind Med ; 29(3): 247-57, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8833777

RESUMEN

This study evaluated the relationship between benzene exposure and low white blood cell (WBC) and red blood cell (RBC) counts. Hematologic screening data collected over a 35 year period at a rubber hydrochloride manufacturing plant were analyzed; an increased risk of leukemia had been demonstrated previously among workers at the plant [Infante et al. (1977).' Lancet 2:76-78; Rinsky et al. (1981): Am J Ind Med 2:217-45 (1987): NEJM 316:1044-1050/. Hematologic screening data were available for 657 of 1,037 (63.3%) individuals employed at the plant from 1939 through 1976. There was a total of 21. 710 blood test records (range per individual 1-354). The study utilized a case-control design and estimated benzene exposures using the job exposure matrix developed by Rinsky et al. (1987): NEJM 316:1044-1050]. The effects of benzene exposure in the 30, 90, and 180 days before the blood test date, as well as cumulative exposure up until the blood test date, were examined using conditional logistic regression. For WBCs there was a strong exposure response and all of the exposure metrics selected showed a significant relationship with low blood count. For RBCs there was a weak positive exposure-response, which was significant (p = 0.03) for one of the dose metrics. The finding of an exposure-response relationship in the range of exposures represented in this study, where the maximum daily benzene exposure estimate was 34 ppm, is consistent with findings of several animal studies demonstrating a decrease in peripheral lymphocyte counts at benzene exposures as low as 10 ppm, and a stronger effect of benzene exposure on lymphocytes (as reflected in total WBC count) than on red cells. There was no evidence for a threshold for the hematologic effects of benzene exposure, suggesting that even exposure to relatively low levels of benzene (e.g., <5 ppm) may result in hematologic suppression.


Asunto(s)
Benceno/efectos adversos , Industria Química , Monitoreo del Ambiente/métodos , Recuento de Eritrocitos/efectos de los fármacos , Enfermedades Hematológicas/inducido químicamente , Recuento de Leucocitos/efectos de los fármacos , Exposición Profesional/efectos adversos , Estudios de Casos y Controles , Estudios de Cohortes , Relación Dosis-Respuesta a Droga , Femenino , Enfermedades Hematológicas/sangre , Enfermedades Hematológicas/prevención & control , Humanos , Modelos Logísticos , Masculino , Tamizaje Masivo/métodos , Enfermedades Profesionales/prevención & control , Valores de Referencia , Factores de Riesgo , Goma
13.
Int J Cosmet Sci ; 17(6): 219-31, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19245470

RESUMEN

Synopsis A modified procedure for the determination of total N-nitroso compounds in personal care products was evaluated in collaborative studies organized through the UK Cosmetic Toiletry and Perfumery Association (CTPA). The method offers a true 'totals'determination in that a solution of the whole sample is analysed. Samples are dissolved/suspended in water or aqueous THF, and nitrite/nitrite ester interferences are removed by prior treatment with sulphamic acid. The treated test solution is denitrosated in a single reaction with HBr/acetic acid, in refluxing n-propyl acetate, and 'total'N-nitroso compounds are determined in a chemiluminescence reaction of the released nitric oxide with ozone. The use of a propyl acetate denitrosation solvent and of higher concentrations of HBr have improved both the sensitivity (routine limit of determination at 10 mugkg(-1)) and water tolerance of the method. The method was shown to recover N-nitrosamines quantitatively, and to be sufficiently repeatable and reproducible to be used as a screening technique for N-nitroso compounds in personal care products.

14.
Int J Cosmet Sci ; 17(3): 119-31, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19245496

RESUMEN

Summary From initial rate studies of morpholine nitrosation in aqueous media by nitrite ion in the presence of formaldehyde at pH 5-7 and 25 degrees C, four potential pathways are revealed for the concurrent formation of nitrosamine contaminants in cosmetic and toiletry products. Three of the pathways involve conventional electrophilic nitrosation by XNO reagents of both neutral amine and N-hydroxymethylamine compounds obtained by prior reaction with formaldehyde. The fourth pathway involves a nucleophilic reaction by nitrite ion with the iminium ion derived from N-hydroxymethylamine. For morpholine, reaction via XNO reagents is substantial at pH 5 only, whereas the iminium ion pathway is pre-eminent at pH 7. The concurrent formation of nitrosamines by mechanistically different pathways implies that combinations of nitrosation inhibitors are necessary to minimize contamination of cosmetic and toiletry products. For these different pathways, novel inhibitory compounds are described which fulfil the usual acceptance criteria for cosmetic and toiletry materials. The efficacy of these compounds is assessed against N-nitrosomorpholine formation in the presence of formaldehyde. These include erythorbate, ascorbate, pentanedione and pyranone compounds for the XNO pathways (pH 6) and neutral organic and inorganic salts for the iminium ion pathways (pH 7). Preliminary results for both a bath gel and a cream-base formulation deliberately adulterated with morpholine, diethanolamine, nitrite and a preservative which releases low levels of formaldehyde on decomposition show better than 90% inhibition of nitrosamines by selected pairs of inhibitor compounds on storage at 40 degrees C over several months. This novel technology is the subject of a worldwide patent application.

15.
Br J Cancer ; 67(5): 1086-9, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8494703

RESUMEN

A prospective autopsy study of deaths of women who had been diagnosed previously as having cancer of the breast was performed between October 1986 and December 1990. During the study period 28 deaths occurred and nine of these (32%) were attributable directly to breast cancer; a figure similar to that found in our earlier retrospective study. In this study the autopsy findings in both the breast cancer and non-breast cancer deaths were recorded and five cases underwent post-mortem radiological skeletal survey to detect metastases. The findings confirm the role of the post mortem in modern medicine as a method of auditing clinical practice. Of particular importance, is the finding that the clinical presumption of disseminated breast cancer as a cause of 'terminal' illness in some patients may be misleading and dangerous, possibly denying some patients treatment of potentially remedial conditions by the institution of inappropriate terminal care.


Asunto(s)
Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Femenino , Humanos , Persona de Mediana Edad , Metástasis de la Neoplasia , Estudios Prospectivos , Reino Unido
16.
Pathol Res Pract ; 189(4): 453-7, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8351249

RESUMEN

Audit is now part of any laboratory service. Histopathology is no exception, and we have set up a system which allows us to review 4% of our specimens. These specimens are identified using a random number generator and reviewed by a consultant pathologist. Both slides and wet specimens are reviewed and graded according to a set scheme. The results from the first year of operation (1990) show a high rate of accuracy with no serious diagnostic disagreements between the auditor and the reporting pathologist. However, some errors which we would wish to prevent were detected and the audit has allowed us to take corrective measures. In our opinion, this form of audit is useful and necessary to maintain good clinical practice. The cost is considerable--histopathology is by its nature labour intensive. Recognition of this fact by health boards is essential if such systems are to continue.


Asunto(s)
Auditoría Administrativa , Patología Clínica/normas , Biopsia , Costos y Análisis de Costo , Errores Diagnósticos , Auditoría Administrativa/economía , Patología Clínica/métodos
20.
Q J Med ; 67(252): 319-41, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3060894

RESUMEN

Medical calcification of arteries is common in chronic renal failure. We report on a patient with extensive calcification of the arterial media who developed symmetrical acral gangrene and severe cardiac failure shortly after cadaveric renal transplantation. At necropsy, the medial calcification was found to be accompanied by extensive intimal proliferation and multiple antemortem fractures, some healing by callus formation. Such medial calcification, which is similar to Monckeberg's sclerosis, affected all systemic arteries except the aorta, pulmonary artery and transplanted renal artery. Six years before this terminal illness he had undergone total parathyroidectomy for osteitis fibrosa associated with ruptured tendons. We review previous reports of patients with the syndrome of acral gangrene in azotaemic renal failure and discuss the histopathological features and pathogenesis in relation to the unusual features of our patient.


Asunto(s)
Arterias/patología , Calcinosis/etiología , Extremidades/patología , Fallo Renal Crónico/complicaciones , Adulto , Calcinosis/patología , Gangrena , Humanos , Fallo Renal Crónico/patología , Masculino
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