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1.
J Acoust Soc Am ; 156(2): 1380-1390, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39196104

RESUMO

For most of his illustrious career, Ken Stevens focused on examining and documenting the rich detail about vocal tract changes available to listeners underlying the acoustic signal of speech. Current approaches to speech inversion take advantage of this rich detail to recover information about articulatory movement. Our previous speech inversion work focused on movements of the tongue and lips, for which "ground truth" is readily available. In this study, we describe acquisition and validation of ground-truth articulatory data about velopharyngeal port constriction, using both the well-established measure of nasometry plus a novel technique-high-speed nasopharyngoscopy. Nasometry measures the acoustic output of the nasal and oral cavities to derive the measure nasalance. High-speed nasopharyngoscopy captures images of the nasopharyngeal region and can resolve velar motion during speech. By comparing simultaneously collected data from both acquisition modalities, we show that nasalance is a sufficiently sensitive measure to use as ground truth for our speech inversion system. Further, a speech inversion system trained on nasalance can recover known patterns of velopharyngeal port constriction shown by American English speakers. Our findings match well with Stevens' own studies of the acoustics of nasal consonants.


Assuntos
Acústica da Fala , Medida da Produção da Fala , Humanos , Masculino , Medida da Produção da Fala/métodos , Adulto , Feminino , Adulto Jovem , Qualidade da Voz , Constrição Patológica , Fala/fisiologia , Endoscopia/métodos , Endoscopia/instrumentação
2.
Osteoporos Int ; 34(2): 399-404, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36472657

RESUMO

We investigated frailty and refracture risk among older adults with a minimal trauma fracture. After adjusting for age, sex, and site of initial fracture, increasing frailty was associated with an increased risk subsequent fracture. These results indicate the need to routinely screen for frailty following an initial fracture among older adults. INTRODUCTION: Minimal trauma fractures are common among older adults, and frailty increases risk of an initial minimal trauma fracture. This study was undertaken to estimate the risk of subsequent fracture based on frailty status at the time of an initial fracture. METHODS: The study population was older adults presenting to hospital, aged 60 years or more, with a minimal trauma fracture. Frailty was estimated using a cumulative deficit approach. The risk of subsequent fracture based on increasing cumulative frailty deficit item group, adjusted for sex, age, and site of initial fracture, was estimated using Cox's proportional hazard model. RESULTS: Between January 2014 and December 2020, 12,115 older adults presented to hospital (8371 women [69%]), with an initial minimal trauma fracture. The average age was 80 years (SD 9.5). Subsequent fractures identified during the follow-up period occurred in 1137 (9.4%) of study participants. The incidence of subsequent fracture ranged from 25.0 per 1000 older adults (95% confidence interval (CI) 22.4 to 27.8) among the lowest frailty deficit group (1 deficit item) to 31.8 per 1000 (95% CI 28.0 to 35.8) among the highest frailty deficit group (4 to 12 deficit items). After adjusting for age, sex, and site of initial fracture, an increasing number of frailty deficit items was associated with increased risk subsequent fracture (p-value for trend = 0.008). CONCLUSION: Our results indicate that following an initial minimal trauma fracture, frailty independently increases the risk of a subsequent fracture. Therefore, it is important at the time of an initial fracture that older women and men are screened for the presence of frailty, and models of care are implemented to reduce the risk of subsequent fracture among this vulnerable group of older adults.


Assuntos
Fraturas Ósseas , Fragilidade , Masculino , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Fragilidade/complicações , Fragilidade/epidemiologia , Fraturas Ósseas/epidemiologia , Incidência , Hospitais , Fatores de Risco
3.
Age Ageing ; 52(7)2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37505990

RESUMO

BACKGROUND: Optimising timely discharge from hospitals is an international priority. In 2020, the Coronavirus disease 2019 (COVID-19) pandemic resulted in the United Kingdom Government implementing the Discharge to Assess (D2A) model across England. This funded temporary care home placement to allow further recovery and assessment of care needs outside of the hospital. OBJECTIVES: Determine if older adults discharged from hospital to care homes after implementation of D2A differ in their characteristics or outcomes. DESIGN AND METHODS: Two cohorts of older adults discharged from hospital to care homes pre- and post-implementation of the D2A model (n = 244), with 6 months of follow-up. Data were extracted from routinely collected healthcare records. RESULTS: The mean duration of the hospital admission was reduced (29 vs. 23 days (P = 0.02)) but discharges to care homes did not increase with implementation of D2A (n = 161 in both cohorts prior to exclusions). In July-December 2020 (post-implementation), 28% of people were living in a private residence 6 months post-discharge, compared with 18% in the same period in 2019 (P = 0.09). When those who died were excluded, this changed to 40 vs. 28% (P = 0.19). There was no change in 6-month mortality (26 vs. 35% (P = 0.17)), and no increase in readmission rate (0.48 vs. 0.63 (P = 0.21) readmissions-per-patient over 6 months). No differences in key characteristics were found. However, patients were placed in care homes further from admission addresses (17.3 vs. 9.8 km (P = 0.00001)). CONCLUSIONS: Implementation of D2A did not result in poorer outcomes but was associated with a reduced length of hospital stay.


Assuntos
COVID-19 , Alta do Paciente , Humanos , Idoso , Estudos de Coortes , Readmissão do Paciente , Assistência ao Convalescente , COVID-19/terapia , Tempo de Internação , Hospitais
4.
J Clin Nurs ; 32(3-4): 477-484, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35212075

RESUMO

BACKGROUND: While advances in healthcare mean people are living longer, increasing frailty is a potential consequence of this. The relationship between frailty among older surgical patients and hospital acquired adverse events has not been extensively explored. We sought to describe the relationship between increasing frailty among older surgical patients and the risk of hospital acquired adverse events. METHODS: We included consecutive surgical admissions among patients aged 70 years or more across the SWSLHD between January 2010 and December 2020. This study used routinely collected ICD-10-AM data, obtained from the government maintained Admitted Patient Data Collection. The relationships between cumulative frailty deficit items and risk of hospital acquired adverse events were assessed using Poisson regression modelling. This study followed the RECORD/STROBE guidelines. RESULTS: During the study period, 44,721 (57% women) older adults were admitted, and 41% (25,306) were planned surgical admissions. The risk of all adverse events increased with increasing number of frailty deficit items, the highest deficit items group (4-12 deficit items) compared with the lowest deficit items group (0 or 1 deficit item): falls adjusted rate ratio (adj RR) = 15.3, (95% confidence interval (CI) 12.1, 19.42); pressure injury adj RR = 21.3 (95% CI 12.53, 36.16); delirium adj RR = 40.9 (95% CI 31.21, 53.55); pneumonia adj RR = 16.5 (95% CI 12.74, 21.27); thromboembolism adj RR = 17.3 (95% CI 4.4, 11.92); and hospital mortality adj RR = 6.2 (95% CI 5.18, 7.37). CONCLUSION: The increase in number of cumulative frailty deficit items among older surgical patients was associated with a higher risk of adverse hospital events. The link offers an opportunity to clinical nursing professionals in the surgical setting, to develop and implement targeted models of care and ensure the best outcomes for frail older adults and their families.


Assuntos
Fragilidade , Idoso , Humanos , Feminino , Masculino , Idoso Fragilizado , Hospitalização , Pacientes , Hospitais , Avaliação Geriátrica
5.
Psychiatr Q ; 94(2): 221-231, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37145257

RESUMO

Although digital health solutions are increasingly popular in clinical psychiatry, one application that has not been fully explored is the utilization of survey technology to monitor patients outside of the clinic. Supplementing routine care with digital information collected in the "clinical whitespace" between visits could improve care for patients with severe mental illness. This study evaluated the feasibility and validity of using online self-report questionnaires to supplement in-person clinical evaluations in persons with and without psychiatric diagnoses. We performed a rigorous in-person clinical diagnostic and assessment battery in 54 participants with schizophrenia (N = 23), depressive disorder (N = 14), and healthy controls (N = 17) using standard assessments for depressive and psychotic symptomatology. Participants were then asked to complete brief online assessments of depressive (Quick Inventory of Depressive Symptomatology) and psychotic (Community Assessment of Psychic Experiences) symptoms outside of the clinic for comparison with the ground-truth in-person assessments. We found that online self-report ratings of severity were significantly correlated with the clinical assessments for depression (two assessments used: R = 0.63, p < 0.001; R = 0.73, p < 0.001) and psychosis (R = 0.62, p < 0.001). Our results demonstrate the feasibility and validity of collecting psychiatric symptom ratings through online surveys. Surveillance of this kind may be especially useful in detecting acute mental health crises between patient visits and can generally contribute to more comprehensive psychiatric treatment.


Assuntos
Depressão , Inquéritos Epidemiológicos , Internet , Transtornos Psicóticos , Autorrelato , Saúde Mental/normas , Intervenção Baseada em Internet , Inquéritos Epidemiológicos/métodos , Inquéritos Epidemiológicos/normas , Reprodutibilidade dos Testes , Depressão/diagnóstico , Depressão/psicologia , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Esquizofrenia/diagnóstico , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/psicologia
6.
J Am Pharm Assoc (2003) ; 62(3): 740-749.e3, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35012893

RESUMO

BACKGROUND: Lean methodology, specifically value stream mapping, can be used to identify and reduce inefficiencies in the medication synchronization process. OBJECTIVES: The objectives of this study were to (1) evaluate potential medication synchronization process improvements to reduce nonvalue-added actions, (2) assess fidelity to the medication synchronization core components, and (3) identify the best process for medication synchronization for an independent community pharmacy with multiple locations. METHODS: This study used an observational, cross-sectional design. A value stream map was created to provide a detailed illustration of each step in the medication synchronization process. Time for each step of the medication synchronization process was observed on site on different days and times as well as the time required to process, package, and verify prescription medications. These steps were conducted before interventions were made to the process and after to compare the difference. The organizational readiness for change tool was administered to employees of the independent pharmacy before interventions to determine their perspective of the medication synchronization process and assess their readiness for change. RESULTS: Owing to various interventions made to the medication synchronization process, 2 steps in the process were eliminated. This resulted in a decrease in adherence packaging time workflow by 69.4%. Staff (n = 9) rated the medication synchronization process on 4 components: acceptability of the current process (13.8 ± 3.6), intervention appropriateness (13.7 ± 3.7), feasibility of a new medication synchronization process (17.1 ± 2.3), and organizational level of support (21.8 ± 4.1). CONCLUSION: Value stream mapping proved to be a valuable tool in identifying inefficiencies in the medication synchronization process and reducing nonvalue-added waste. The result was a decrease in time required for adherence packaging workflow and a more standardized medication synchronization process across multiple independent pharmacy locations. This more standardized process can play a key role in improving the continuity of patient care, increasing medication adherence, and in turn decreasing the number of hospital admissions.


Assuntos
Serviços Comunitários de Farmácia , Farmácias , Farmácia , Estudos Transversais , Humanos , Adesão à Medicação
7.
Int J Mol Sci ; 23(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35163806

RESUMO

Prevalence of type 2 diabetes increased from 2.5% of the US population in 1990 to 10.5% in 2018. This creates a major public health problem, due to increases in long-term complications of diabetes, including neuropathy, retinopathy, nephropathy, skin ulcers, amputations, and atherosclerotic cardiovascular disease. In this review, we evaluated the scientific basis that supports the use of physiologic insulin resensitization. Insulin resistance is the primary cause of type 2 diabetes. Insulin resistance leads to increasing insulin secretion, leading to beta-cell exhaustion or burnout. This triggers a cascade leading to islet cell destruction and the long-term complications of type 2 diabetes. Concurrent with insulin resistance, the regular bursts of insulin from the pancreas become irregular. This has been treated by the precise administration of insulin more physiologically. There is consistent evidence that this treatment modality can reverse the diabetes-associated complications of neuropathy, diabetic ulcers, nephropathy, and retinopathy, and that it lowers HbA1c. In conclusion, physiologic insulin resensitization has a persuasive scientific basis, significant treatment potential, and likely cost benefits.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Resistência à Insulina , Insulina Regular Humana/uso terapêutico , Diabetes Mellitus Tipo 2/metabolismo , Hemoglobinas Glicadas/metabolismo , Humanos , Secreção de Insulina/efeitos dos fármacos , Insulina Regular Humana/farmacologia , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo
9.
BMC Musculoskelet Disord ; 21(1): 133, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32111200

RESUMO

BACKGROUND: One in three women and one in five men are expected to experience a minimal-trauma-fracture after the age of 50-years, which increases the risk of subsequent fracture. Importantly, timely diagnosis and optimal treatment in the form of a fracture liaison service (FLS), has been shown to reduce this risk of a subsequent fracture. However, baseline risk of subsequent fracture among this group of FLS patients has not been well described. Therefore, this study aims to estimate absolute risk of subsequent fracture, among women and men aged 50-years or more, presenting to hospital with a minimal-trauma-fracture. METHODS: Women and men aged 50-years or more with a minimal-trauma-fracture, presenting to hospitals across the South Western Sydney Local Health District between January 2003 and December 2017 were followed to identify subsequent fracture presentations to hospital. Absolute risk of subsequent fracture was estimated, by taking into account the competing risk of death. RESULTS: Between January 2003 and December 2017-15,088 patients presented to the emergency departments of the five hospitals in the SWSLHD (11,149, women [74%]), with minimal-trauma-fractures. Subsequent fractures identified during the follow-up period (median = 4.5 years [IQR, 1.6-8.2]), occurred in 2024 (13%) patients. Death during the initial hospital stay, or during a subsequent hospital visit was recorded among 1646 patients (11%). Women were observed to have 7.1% risk of subsequent fracture after 1-year, following an initial fracture; and, the risk of subsequent fracture after 1-year was 6.2% for men. After 5-years the rate among women was 13.7, and 11.3% for men, respectively. Cumulative risk of subsequent fracture when initial fractures were classified as being at proximal or distal sites are also presented. CONCLUSION: This study has estimated the baseline risk of subsequent fracture among women and men presenting to hospital with minimal trauma fractures. Importantly, this information can be used to communicate risk to patients deciding to attend an osteoporosis refracture prevention clinic, and highlight the need for screening, and initial of treatment when indicated, once a minimal-trauma-fracture has occurred.


Assuntos
Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/prevenção & controle , Prevenção Secundária/métodos , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Conservadores da Densidade Óssea/uso terapêutico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/diagnóstico , Fraturas por Osteoporose/cirurgia , Recidiva , Medição de Risco , Fatores de Risco , Fatores Sexuais
10.
J Acoust Soc Am ; 146(1): 316, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31370597

RESUMO

Speech inversion is a well-known ill-posed problem and addition of speaker differences typically makes it even harder. Normalizing the speaker differences is essential to effectively using multi-speaker articulatory data for training a speaker independent speech inversion system. This paper explores a vocal tract length normalization (VTLN) technique to transform the acoustic features of different speakers to a target speaker acoustic space such that speaker specific details are minimized. The speaker normalized features are then used to train a deep feed-forward neural network based speech inversion system. The acoustic features are parameterized as time-contextualized mel-frequency cepstral coefficients. The articulatory features are represented by six tract-variable (TV) trajectories, which are relatively speaker invariant compared to flesh point data. Experiments are performed with ten speakers from the University of Wisconsin X-ray microbeam database. Results show that the proposed speaker normalization approach provides an 8.15% relative improvement in correlation between actual and estimated TVs as compared to the system where speaker normalization was not performed. To determine the efficacy of the method across datasets, cross speaker evaluations were performed across speakers from the Multichannel Articulatory-TIMIT and EMA-IEEE datasets. Results prove that the VTLN approach provides improvement in performance even across datasets.

11.
Appl Opt ; 57(22): E142-E146, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30117912

RESUMO

The characterization of an amplified piezoelectric actuator (APA) as a new axial scanning method for multiple-reference optical coherence tomography (MR-OCT) is described. MR-OCT is a compact optical imaging device based on a recirculating reference-arm-scanning optical delay using a partial mirror that can enhance the imaging depth range by more than 10 times the reference mirror's scanning amplitude. The scanning amplitude of the used APA was varied between 30 µm and 250 µm, depending on the scanning frequency of between 0.8 kHz and 1.2 kHz. A silver-coated miniature mirror was attached to the APA via ultraviolet-cured optical adhesive, and the light source was a super-luminescent diode with 1310 nm center wavelength and 56 nm bandwidth. The sensitivity was measured with and without the partial mirror in the reference delay line as a function of scan speed, frequency, and range, therefore providing results for MR-OCT and TD-OCT modes. It was found that the APA provides more than twice the mechanical scanning range compared to other opto-mechanic actuators, but results indicate degradation of signal-to-noise ratio and sensitivity at larger imaging depths. In conjunction with MR-OCT, the scan range of maximum 200 µm can be enhanced up to 1-1.5 mm by using a reduced amount of orders of reflections, which could be of interest to increase sensitivity in the future.

12.
Appl Opt ; 57(25): 7377, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30182958

RESUMO

This erratum is submitted to correct information regarding Fig. 8 of Appl. Opt.57, E142 (2018)APOPAI0003-693510.1364/AO.57.00E142.

13.
Geochem Trans ; 18(1): 4, 2017 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-29086805

RESUMO

To identify the causes of salinization and arsenic contamination of surface water on an embanked island (i.e., polder) in the tidal delta plain of SW Bangladesh we collected and analyzed water samples in the dry (May) and wet (October) seasons in 2012-2013. Samples were collected from rice paddies (wet season), saltwater ponds used for brine shrimp aquaculture (dry season), freshwater ponds and tidal channels (both wet and dry season), and rainwater collectors. Continuous measurements of salinity from March 2012 to February 2013 show that tidal channel water increases from ~0.15 ppt in the wet season up to ~20 ppt in the dry season. On the polder, surface water exceeds the World Health Organization drinking water guideline of 10 µg As/L in 78% of shrimp ponds and 27% of rice paddies, raising concerns that produced shrimp and rice could have unsafe levels of As. Drinking water sources also often have unsafe As levels, with 83% of tubewell and 43% of freshwater pond samples having >10 µg As/L. Water compositions and field observations are consistent with shrimp pond water being sourced from tidal channels during the dry season, rather than the locally saline groundwater from tubewells. Irrigation water for rice paddies is also obtained from the tidal channels, but during the wet season when surface waters are fresh. Salts become concentrated in irrigation water through evaporation, with average salinity increasing from 0.43 ppt in the tidal channel source to 0.91 ppt in the rice paddies. Our observations suggest that the practice of seasonally alternating rice and shrimp farming in a field has a negligible effect on rice paddy water salinity. Also, shrimp ponds do not significantly affect the salinity of adjacent surface water bodies or subjacent groundwater because impermeable shallow surface deposits of silt and clay mostly isolate surface water bodies from each other and from the shallow groundwater aquifer. Bivariate plots of conservative element concentrations show that all surface water types lie on mixing lines between dry season tidal channel water and rainwater, i.e., all are related by varying degrees of salinization. High As concentrations in dry season tidal channel water and shrimp ponds likely result from groundwater exfiltration and upstream irrigation in the dry season. Arsenic is transferred from tidal channels to rice paddies through irrigation. Including groundwater samples from the same area (Ayers et al. in Geochem Trans 17:1-22, 2016), principal components analysis and correlation analysis reveal that salinization explains most variation in surface water compositions, whereas progressive reduction of buried surface water by dissolved organic carbon is responsible for the nonconservative behavior of S, Fe, and As and changes in Eh and alkalinity of groundwater.

14.
Am J Bot ; 104(5): 694-718, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28533204

RESUMO

PREMISE OF THE STUDY: Extant dwarf mistletoes (Arceuthobium M. Bieb., Viscaceae) are hemiparasites with complex roles in nature. They are one of the most severe pests in northern hemisphere conifer forests, but they also enhance the structural complexity and species diversity of the forests. Here, we describe the first pre-Miocene macrofossils of dwarf mistletoes. The fossils from Eocene Baltic amber provide new insights into the morphological evolution of the Arceuthobium lineage and its paleobiogeography. METHODS: The amber inclusions were investigated with light microscopy and compared with extant Viscaceae and to historic descriptions of lost Baltic amber fossils with affinities to Viscaceae. KEY RESULTS: Six fossil species of the Arceuthobium lineage, A. johnianum comb. nov., A. mengeanum comb. nov., A. conwentzii sp. nov., A. groehnii sp. nov., A. viscoides comb. nov. and A. obovatum sp. nov., occurred in source forests of Baltic amber, representing the oldest macrofossil evidence of dwarf mistletoes. They share morphological features of their bracts, internodes, fruits, and stomata with extant Arceuthobium. Differences from extant dwarf mistletoes, such as the perianth merosity, the nonfusion of squamate bracts and presence of oblanceolate expanded leaves, indicate their affiliation to an ancient lineage of the genus. CONCLUSIONS: The occurrence of six species of dwarf mistletoes in a single amber deposit suggests Arceuthobium was a keystone taxon of the Baltic amber source area. As in extant conifer forests, they probably influenced the structural complexity of the forest, not only leading to more open woodlands but also increasing species diversity, at least at a microhabitat scale.


Assuntos
Âmbar , Viscaceae/classificação , Países Bálticos , Biota , Fósseis
15.
J Ment Health ; 26(6): 530-537, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28675327

RESUMO

BACKGROUND: Since 2001, a policy of positive mental health recovery has been promoted in the UK, with service user involvement. This has not been easy to implement in the clinical setting. AIMS: To develop and validate a brief self-report, service user-designed, outcome measure (Mini-SeRvE), for clinical use, including spiritual and religious issues. METHODS: From the previously developed Service user Recovery Evaluation scale (SeRvE), 15 questions were selected for Mini-SeRvE which was self-completed by 207 people; 100 service users and, for comparison, 107 staff. Results were analysed using SPSS software (SPSS Inc., Chicago, IL). RESULTS: Mini-SeRvE is reliable, Cronbach's alpha 0.852. Correlation with another recovery scale, Mental Health Recovery Measure, was high, r = 0.819. Three reliable subscales emerged; existential well-being (EWB), mental ill-being (MIB) and religious well-being (RWB). Scores of the EWB and MIB subscales were higher for staff, consistent with higher mental well-being. Religious well-being scores were higher in service users, who also rated religion as more important to them. CONCLUSIONS: Mini-SeRvE is a valid measure of service user recovery. The importance of religion/spiritual belief for our users is highlighted, this being reflected in the subject matter of Mini-SeRvE. Mini-SeRvE assessments could show individual priorities, evaluate therapy and aid clinical decision-making.


Assuntos
Transtornos Mentais/diagnóstico , Transtornos Mentais/terapia , Saúde Mental , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Transtornos Mentais/psicologia , Recuperação da Saúde Mental , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Satisfação Pessoal , Recuperação de Função Fisiológica , Espiritualidade , Inquéritos e Questionários , Adulto Jovem
16.
Lasers Surg Med ; 48(1): 77-82, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26612183

RESUMO

BACKGROUND AND OBJECTIVES: Monitoring the curing kinetics of light-activated resin is a key area of research. These resins are used in restorative applications and particularly in dental applications. They can undergo volumetric shrinkage due to poor control of the depth dependent curing process, modulated by the intensity and duration of the curing light source. This often results in the formation of marginal gaps, causing pain and damage to the restoration site. In this study, we demonstrate the capabilities of a correlation method applied using a multiple references optical coherence tomography (MR-OCT) architecture to monitor the curing of the resin. STUDY DESIGN/MATERIALS AND METHODS: A MR-OCT system is used in this study to monitor the curing of the resin. The system operates at the center wavelength of 1310 nm with an A-scan rate of 1200 A-scans per second. The axial and lateral resolution of the system is ∼13 µm and ∼27 µm. The method to determine the intensity correlation between adjacent B-frames is based on the Pearson correlation coefficient for a region of interest. Calculating the correlation coefficient for multiple B-frames related to the first B-frame at regular spaced time points, shows for a noncured resin a reduction of the correlation coefficient over time due to Brownian motion. The time constant of the reduction of the correlation value is a measure for the progress of the polymerization during LED light irradiation of the resin. The proposed approach is potentially a low-cost, powerful and unique optical imaging modality for measuring the curing behavior of dental resin and other resins, coatings, and adhesives in medical and industrial applications. RESULTS: To demonstrate the proposed method to monitor the curing process, a light-activated resin composite from GRADIA DIRECT ANTERIOR (GC Corporation, Japan) is studied. The curing time of resin was measured and monitored as a function of depth. The correlation coefficient method is highly sensitive to Brownian motion. The process of curing results in a change in intensity as measured by the MR-OCT signal and hence can be monitored using this method. CONCLUSIONS: These results show that MR-OCT has the potential to measure the curing time and monitor the curing process as a function of depth. Moreover, MR-OCT as a product has potential to be compact, low-cost and to fit into a smartphone. Using such a device for monitoring the curing of the resin will be suitable for dentists in stationary and mobile clinical settings.


Assuntos
Resinas Compostas/farmacocinética , Lâmpadas de Polimerização Dentária , Tomografia de Coerência Óptica
17.
J Cardiovasc Electrophysiol ; 26(6): 686-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25711237

RESUMO

Implantable cardioverter defibrillator (ICD) lead insulation failure and conductor externalization have been increasingly reported. The 7.8F silicon-insulated Linox SD and Linox S ICD leads (Biotronik, Berlin, Germany) were released in 2006 and 2007, respectively, with an estimated 85,000 implantations worldwide. A 39-year-old female suffered an out-of-hospital ventricular fibrillation (VF) arrest with successful resuscitation. An ICD was implanted utilizing a single coil active fixation Linox(Smart) S lead (Biotronik, Berlin, Germany). A device-triggered alert approximately 3 years after implantation confirmed nonphysiological high rate sensing leading to VF detection. A chest X-ray showed an abnormality of the ICD lead and fluoroscopic screening confirmed conductor externalization proximal to the defibrillator coil. In view of the combined electrical and fluoroscopic abnormalities, urgent lead extraction and replacement were performed. A review of Linox (Biotronik) and Vigila (Sorin Group, Milan, Italy) lead implantations within our center (n = 98) identified 3 additional patients presenting with premature lead failure, 2 associated with nonphysiological sensed events and one associated with a significant decrease in lead impedance. All leads were subsequently removed and replaced. This case provides a striking example of insulation failure affecting the Linox ICD lead and, we believe, is the first to demonstrate conductor externalization manifesting both electrical and fluoroscopic abnormalities.


Assuntos
Desfibriladores Implantáveis/efeitos adversos , Falha de Equipamento , Adulto , Feminino , Humanos , Estudos Retrospectivos , Fibrilação Ventricular/etiologia
18.
Appl Opt ; 54(18): 5634-8, 2015 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-26193006

RESUMO

Optical coherence tomography (OCT) is emerging as a powerful noncontact imaging technique, allowing high-quality cross-sectional imaging of scattering specimens nondestructively. However, the complexity and cost of current embodiments of an OCT system limit its use in various nondestructive testing (NDT) applications at resource-limited settings. In this paper, we demonstrate the feasibility of a novel low-cost OCT system for a range of nondestructive testing (NDT) applications. The proposed imaging system is based on an enhanced time-domain OCT system with a low cost and small form factor reference arm optical delay, called multiple reference OCT (MR-OCT), which uses a miniature voice coil actuator and a partial mirror for extending the axial scan range. The proposed approach is potentially a low-cost, compact, and unique optical imaging modality for a range of NDT applications in a low-resource setting. Using this method, we demonstrated the capability of MR-OCT to perform cross-sectional and volumetric imaging at 1200 A-scans per second.

19.
Healthc Manage Forum ; 28(1): 8-11, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25838564

RESUMO

Les médecins, la direction, le personnel et les bénévoles des entreprises veulent former de futurs leaders au sein de leur organisation. Le présent article décrit les efforts pour concevoir, mettre en œuvre et évaluer un programme de mentorat d'un an utilisé pour la première fois par le Glenrose Rehabilitation Hospital des Alberta Health Services. Des sondages d'évaluation ont été analysés pour faire ressortir les facteurs de succès décisifs, qui intégraient un vaste processus de candidatures diversifié de mentorés et de mentors, des critères bien définis de sélection ou de jumelage de mentorés et de mentors et un programme visant à soutenir l'acquisition du savoir par des projets, des séances d'apprentissage et des présentations.

20.
Healthc Manage Forum ; 28(1): 4-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25838563

RESUMO

With enterprise-wide interest by physicians, management, staff, and volunteers in developing future leaders across their organization, this article describes efforts to design, implement, and evaluate an inaugural, 1-year formal mentoring program for the Glenrose Rehabilitation Hospital, Alberta Health Services. Evaluation surveys were analyzed highlighting critical success factors incorporating a broad, diverse mentee/mentor applicant process, well-defined mentee/mentor selection/matching criteria, and use of a formal program to support knowledge acquisition through projects, learning sessions, and presentations.

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