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2.
J Prev Alzheimers Dis ; 10(4): 765-770, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37874098

RESUMO

Aducanumab is the first FDA-approved amyloid-lowering immunotherapy for Alzheimer's disease. There is little real-world data to guide management of amyloid-related imaging abnormalities (ARIA), a potentially serious side-effect which requires surveillance with magnetic resonance imaging. We report our experiences in managing ARIA in patients receiving aducanumab at the Butler Hospital Memory and Aging Program during the year following FDA approval. We followed the Appropriate Use Recommendations for aducanumab to guide patient selection, detection, and management of ARIA (1). ARIA-E occurred in 6 out of 24 participants treated; all APOE-ε4 carriers. Treatment was discontinued in 4 cases of moderate-severe ARIA-E, temporarily held in 1 moderate case, and dosed through in 1 mild case (mean duration = 3 months, range, 1-6 months). No participants required hospitalization or high dose corticosteroids. Participants on anticoagulation were excluded and no macrohemorrhages occurred. These data support the measured approaches to treatment outlined in the Appropriate Use Recommendations.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Anticorpos Monoclonais Humanizados/efeitos adversos , Amiloide , Imageamento por Ressonância Magnética
3.
Parasitology ; 146(11): 1421-1428, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31267883

RESUMO

Angiostrongylus cantonensis is a pathogenic nematode and the cause of neuroangiostrongyliasis, an eosinophilic meningitis more commonly known as rat lungworm disease. Transmission is thought to be primarily due to ingestion of infective third stage larvae (L3) in gastropods, on produce, or in contaminated water. The gold standard to determine the effects of physical and chemical treatments on the infectivity of A. cantonensis L3 larvae is to infect rodents with treated L3 larvae and monitor for infection, but animal studies are laborious and expensive and also raise ethical concerns. This study demonstrates propidium iodide (PI) to be a reliable marker of parasite death and loss of infective potential without adversely affecting the development and future reproduction of live A. cantonensis larvae. PI staining allows evaluation of the efficacy of test substances in vitro, an improvement upon the use of lack of motility as an indicator of death. Some potential applications of this assay include determining the effectiveness of various anthelmintics, vegetable washes, electromagnetic radiation and other treatments intended to kill larvae in the prevention and treatment of neuroangiostrongyliasis.


Assuntos
Angiostrongylus cantonensis/fisiologia , Bioensaio/métodos , Parasitologia/métodos , Propídio/química , Angiostrongylus cantonensis/crescimento & desenvolvimento , Animais , Biomarcadores/análise , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Ratos , Ratos Wistar
4.
Phys Rev Lett ; 120(21): 211804, 2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29883176

RESUMO

The Majorana Demonstrator is an ultralow-background experiment searching for neutrinoless double-beta decay in ^{76}Ge. The heavily shielded array of germanium detectors, placed nearly a mile underground at the Sanford Underground Research Facility in Lead, South Dakota, also allows searches for new exotic physics. Free, relativistic, lightly ionizing particles with an electrical charge less than e are forbidden by the standard model but predicted by some of its extensions. If such particles exist, they might be detected in the Majorana Demonstrator by searching for multiple-detector events with individual-detector energy depositions down to 1 keV. This search is background-free, and no candidate events have been found in 285 days of data taking. New direct-detection limits are set for the flux of lightly ionizing particles for charges as low as e/1000.

5.
Phys Rev Lett ; 118(16): 161801, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28474933

RESUMO

We present new limits on exotic keV-scale physics based on 478 kg d of Majorana Demonstrator commissioning data. Constraints at the 90% confidence level are derived on bosonic dark matter (DM) and solar axion couplings, Pauli exclusion principle violating (PEPV) decay, and electron decay using monoenergetic peak signal limits above our background. Our most stringent DM constraints are set for 11.8 keV mass particles, limiting g_{Ae}<4.5×10^{-13} for pseudoscalars and (α^{'}/α)<9.7×10^{-28} for vectors. We also report a 14.4 keV solar axion coupling limit of g_{AN}^{eff}×g_{Ae}<3.8×10^{-17}, a 1/2ß^{2}<8.5×10^{-48} limit on the strength of PEPV electron transitions, and a lower limit on the electron lifetime of τ_{e}>1.2×10^{24} yr for e^{-}→ invisible.

6.
Nature ; 535(7613): 505-10, 2016 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-27398617

RESUMO

Dopaminergic projection axons from the midbrain to the striatum are crucial for motor control, as their degeneration in Parkinson disease results in profound movement deficits. Paradoxically, most recording methods report rapid phasic dopamine signalling (~100-ms bursts) in response to unpredicted rewards, with little evidence for movement-related signalling. The leading model posits that phasic signalling in striatum-targeting dopamine neurons drives reward-based learning, whereas slow variations in firing (tens of seconds to minutes) in these same neurons bias animals towards or away from movement. However, current methods have provided little evidence to support or refute this model. Here, using new optical recording methods, we report the discovery of rapid phasic signalling in striatum-targeting dopaminergic axons that is associated with, and capable of triggering, locomotion in mice. Axons expressing these signals were largely distinct from those that responded to unexpected rewards. These results suggest that dopaminergic neuromodulation can differentially impact motor control and reward learning with sub-second precision, and indicate that both precise signal timing and neuronal subtype are important parameters to consider in the treatment of dopamine-related disorders.


Assuntos
Axônios/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Locomoção/fisiologia , Recompensa , Aceleração , Animais , Feminino , Aprendizagem/fisiologia , Masculino , Camundongos , Neostriado/citologia , Neostriado/metabolismo , Optogenética , Transdução de Sinais , Fatores de Tempo
7.
Prev Chronic Dis ; 13: E32, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26940299

RESUMO

INTRODUCTION: Competitive beverages are drinks sold outside of the federally reimbursable school meals program and include beverages sold in vending machines, a la carte lines, school stores, and snack bars. Competitive beverages include sugar-sweetened beverages, which are associated with overweight and obesity. We described competitive beverage availability 9 years after the introduction in 2004 of district-wide nutrition standards for competitive beverages sold in Boston Public Schools. METHODS: In 2013, we documented types of competitive beverages sold in 115 schools. We collected nutrient data to determine compliance with the standards. We evaluated the extent to which schools met the competitive-beverage standards and calculated the percentage of students who had access to beverages that met or did not meet the standards. RESULTS: Of 115 schools, 89.6% met the competitive beverage nutrition standards; 88.5% of elementary schools and 61.5% of middle schools did not sell competitive beverages. Nutrition standards were met in 79.2% of high schools; 37.5% did not sell any competitive beverages, and 41.7% sold only beverages meeting the standards. Overall, 85.5% of students attended schools meeting the standards. Only 4.0% of students had access to sugar-sweetened beverages. CONCLUSION: A comprehensive, district-wide competitive beverage policy with implementation support can translate into a sustained healthful environment in public schools.


Assuntos
Bebidas/estatística & dados numéricos , Distribuidores Automáticos de Alimentos , Serviços de Alimentação/normas , Política Nutricional , Instituições Acadêmicas , Adolescente , Boston , Bebidas Gaseificadas/estatística & dados numéricos , Criança , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Adoçantes Calóricos/análise , Valor Nutritivo , Estudantes
8.
Am J Public Health ; 105(9): 1777-83, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26180950

RESUMO

OBJECTIVES: We evaluated a low-cost strategy for schools to improve the convenience and appeal of drinking water. METHODS: We conducted a group-randomized, controlled trial in 10 Boston, Massachusetts, schools in April through June 2013 to test a cafeteria-based intervention. Signage promoting water and disposable cups were installed near water sources. Mixed linear regression models adjusting for clustering evaluated the intervention impact on average student water consumption over 359 lunch periods. RESULTS: The percentage of students in intervention schools observed drinking water during lunch nearly doubled from baseline to follow-up compared with controls (+ 9.4%; P < .001). The intervention was associated with a 0.58-ounce increase in water intake across all students (P < .001). Without cups, children were observed drinking 2.4 (SE = 0.08) ounces of water from fountains; with cups, 5.2 (SE = 0.2) ounces. The percentage of intervention students observed with sugar-sweetened beverages declined (-3.3%; P < .005). CONCLUSIONS: The current default of providing water through drinking fountains in cafeterias results in low water consumption. This study shows that an inexpensive intervention to improve drinking water's convenience by providing cups can increase student water consumption.


Assuntos
Água Potável , Promoção da Saúde , Instituições Acadêmicas , Adolescente , Boston , Criança , Feminino , Humanos , Masculino
9.
Ann Oncol ; 26(5): 1019-1025, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25678586

RESUMO

BACKGROUND: Molecular phenotypes of invasive breast cancer predict early recurrence. Ductal carcinoma in situ (DCIS) exhibits similar phenotypes, but their frequency and significance remain unclear. To determine whether DCIS molecular phenotypes predict recurrence, 314 women (median age 57.7 years) with primary DCIS who were screened or entered DCIS trials in a specialist breast unit from 1990 to 2010 were studied. PATIENTS AND METHODS: Expression of Ki67, estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) within primary DCIS was established using immunohistochemistry (IHC). Patients were subdivided into molecular phenotypes using IHC surrogates [Luminal A (ER/PR+HER2-), Luminal B (ER/PR+/HER2+), HER2 type (ER and PR-/HER2+) or triple negative (ER/PR/HER2)] and recurrence rates compared. RESULTS: Overall, there were 57 (18.2%) recurrences, 35 (11.2%) DCIS and 22 (7%) invasive cancer. A low rate of recurrence at 5 years was seen in Luminal A DCIS (7.6%), compared with 15.8%-36.1% in other phenotypes. Independent predictors of overall recurrence on multivariate analysis were involved (<1 mm) surgical margins (HR 4.31, P < 0.001), high-grade lesions (HR 2.28, P < 0.024) and molecular phenotype (HR 5.14, P = 0.001 for Luminal B; HR 6.46, P < 0.001 for HER2 type and HR 3.27, P = 0.028 for triple-negative disease compared with Luminal A DCIS). Independent predictors for invasive recurrence were high Ki67 expression (HR 1.04, P = 0.021) and molecular phenotype (HR 13.4, P = 0.014 for Luminal B; HR 11.4, P = 0.027 for HER2 type and HR 10.3, P = 0.031 for triple negative compared with Luminal A DCIS). CONCLUSIONS: DCIS molecular phenotype predicts for both overall and invasive recurrence. HER2 testing of DCIS could help clinicians individualise the treatment of patients with DCIS.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Carcinoma Intraductal não Infiltrante/química , Imuno-Histoquímica , Técnicas de Diagnóstico Molecular , Recidiva Local de Neoplasia , Neoplasias de Mama Triplo Negativas/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma Intraductal não Infiltrante/mortalidade , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/terapia , Distribuição de Qui-Quadrado , Intervalo Livre de Doença , Inglaterra , Feminino , Humanos , Estimativa de Kaplan-Meier , Antígeno Ki-67/análise , Pessoa de Meia-Idade , Análise Multivariada , Fenótipo , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Receptor ErbB-2/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/terapia
10.
BJR Case Rep ; 1(1): 20150010, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-30363205

RESUMO

A 56-year-old female was recalled for assessment following screening mammography that demonstrated a new 9-mm indeterminate density in the left breast. Clinical breast examination was normal. Ultrasound confirmed a 9-mm predominantly well-defined hypoechoic breast mass. Core biopsy demonstrated large histiocytes with emperipolesis and positive staining for S100, which is consistent with Rosai-Dorfman disease (RDD). Multidisciplinary team discussion concluded case concordance. The patient was discharged back to the screening programme. RDD is a rare, benign condition that may mimic breast cancer. This case demonstrates that identification of RDD on core needle biopsy may help avoid unnecessary surgery.

11.
Eur J Surg Oncol ; 40(7): 813-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24797703

RESUMO

INTRODUCTION: Axillary ultrasound (AUS) with fine-needle aspiration (FNA) biopsy of abnormal lymph nodes is important for pre-operative staging and planning the surgical management of the axilla. Invasive lobular carcinoma (ILC) metastases are thought to be difficult to detect because the cells are small and on cytology resemble lymphocytes. To investigate this we directly compared the sensitivity of pre-operative axillary staging between ILC and invasive ductal carcinoma (IDC). METHOD: Consecutive patients that presented in a single breast unit with pure IDC between April 2005 and December 2006 and pure ILC between January 2008 and December 2012 were retrospectively identified from pathology records. Pre-operative axillary ultrasound and FNA biopsy results were compared with post-operative histopathology from the sentinel node biopsy (SNB) or axillary lymph node dissection (ALND). RESULTS: A total of 275 and 142 axillae were identified in the IDC and ILC groups respectively. In the node positive patients there was no significant difference in the sensitivity of AUS (IDC vs. ILC; 58.7% vs. 52.8%). However, there was a significant difference in the sensitivity of ultrasound-guided FNA biopsy of abnormal nodes (IDC vs. ILC; 98.4% vs. 53.6%; p < 0.001). CONCLUSION: AUS has comparative sensitivities between IDC and ILC populations. In contrast, FNA biopsy of abnormal axillary nodes is clearly less sensitive in the ILC group. In these patients, who have abnormal AUS, we suggest that a core biopsy is required to improve the pre-operative staging and prevent unnecessary surgical procedures.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Linfonodos/patologia , Linfonodos/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Biópsia por Agulha Fina/métodos , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/cirurgia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/cirurgia , Estudos de Coortes , Bases de Dados Factuais , Feminino , Humanos , Biópsia Guiada por Imagem/métodos , Excisão de Linfonodo/métodos , Mastectomia/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cuidados Pré-Operatórios/métodos , Estudos Retrospectivos , Sensibilidade e Especificidade , Biópsia de Linfonodo Sentinela/métodos , Ultrassonografia
12.
Eur J Surg Oncol ; 40(3): 249-54, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24433818

RESUMO

INTRODUCTION: DCIS accounts for 20% of screen-detected breast cancers, but also presents symptomatically. Historically, approximately 5% of DCIS was thought to be symptomatic, but accurate evaluation of the presentation of symptomatic DCIS is needed to determine its incidence and tumour biology. METHODS: Clinico-pathological details of a consecutive series of patients presenting to a single breast-unit, with a pre-operative diagnosis of DCIS, were selected. Data included age, mode of presentation, pre-operative clinical and radiographical findings. The final tumour histology, operation, size, grade, ER status (and HER2 expression in invasive cases) were recorded. RESULTS: 375 patients had a pre-operative histological diagnosis of DCIS. 308 (82%) screen-detected (median age 59), 67 (18%) presented via symptomatic clinics (median age 50). At final histology 286 (74%) were pure DCIS, and 67 (23%) had an invasive focus. 43% (29/67) of symptomatic cases had an invasive focus at final histology versus 19% (60/308) screen-detected (p ≤ 0.001). 31% (9/29) of symptomatic, versus 10% (6/60) of screen-detected cases with invasion were node positive (p = 0.05). 45% (28/62) intermediate/high-grade symptomatic cases had an invasive focus at final histology, compared to 19% (57/297) intermediate/high-grade screen-detected cases. 86% (212/248) screen-detected pure DCIS was ER positive compared to 68% (26/38) symptomatically presenting pure DCIS (p ≤ 0.001). Overall, 13% (38/248) pure DCIS presented symptomatically (p = 0.001). CONCLUSIONS: Overall, thirteen percent of pure DCIS present symptomatically. Nearly half of symptomatically presenting DCIS at core biopsy has an occult invasive focus and is more frequently ER negative. Symptomatic DCIS with an invasive focus is more likely to have lymph node involvement.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/epidemiologia , Carcinoma Intraductal não Infiltrante/patologia , Detecção Precoce de Câncer/métodos , Adulto , Distribuição por Idade , Idoso , Biópsia por Agulha , Neoplasias da Mama/terapia , Carcinoma Intraductal não Infiltrante/terapia , Estudos de Coortes , Terapia Combinada , Feminino , Humanos , Imuno-Histoquímica , Incidência , Mamografia/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Análise de Sobrevida
13.
J Sound Vib ; 332(17): 3909-3923, 2013 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-24031098

RESUMO

The method of tailored Green's functions advocated by Doak (Proceedings of the Royal Society A254 (1960) 129 - 145.) for the solution of aeroacoustic problems is used to analyse the contribution of the mucosal wave to self-sustained modulation of air flow through the glottis during the production of voiced speech. The amplitude and phase of the aerodynamic surface force that maintains vocal fold vibration are governed by flow separation from the region of minimum cross-sectional area of the glottis, which moves back and forth along its effective length accompanying the mucosal wave peak. The correct phasing is achieved by asymmetric motion of this peak during the opening and closing phases of the glottis. Limit cycle calculations using experimental data of Berry et al. (Journal of the Acoustical Society of America 110 (2001) 2539 - 2547.) obtained using an excised canine hemilarynx indicate that the mechanism is robust enough to sustain oscillations over a wide range of voicing conditions.

15.
J Acoust Soc Am ; 133(4): 2340-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23556600

RESUMO

An investigation is made of the influence of subglottal boundary conditions on the prediction of voiced sounds. It is generally assumed in mathematical models of voicing that vibrations of the vocal folds are maintained by a constant subglottal mean pressure pI, whereas voicing is actually initiated by contraction of the chest cavity until the subglottal pressure becomes large enough to separate the vocal folds. The problem is reformulated to determine voicing characteristics in terms of a prescribed volumetric flow rate Qo of air from the lungs-the evolution of the resulting time-dependent subglottal mean pressure p[overline]-(t) is then governed by glottal mechanics, the aeroacoustics of the vocal tract, and the influence of continued contraction of the lungs. The new problem is analyzed in detail for an idealized mechanical vocal system that permits precise specification of all boundary conditions. Predictions of the glottal volume velocity pulse shape are found to be in good general agreement with the traditional constant-pI theory when pI is set equal to the time averaged value of p[overline]-(t). But, in all cases examined the constant-pI approximation yields values of the mean flow rates Qo and sound pressure levels that are smaller by as much as 10%.


Assuntos
Glote/fisiologia , Pulmão/fisiologia , Fonação , Voz , Fenômenos Biomecânicos , Simulação por Computador , Humanos , Modelos Biológicos , Contração Muscular , Análise Numérica Assistida por Computador , Pressão , Músculos Respiratórios/fisiologia , Fatores de Tempo , Vibração
16.
J Affect Disord ; 145(3): 405-8, 2013 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-22884238

RESUMO

BACKGROUND: The child behavior checklist-Juvenile bipolar disorder phenotype (CBCL-JBD) has been proposed as a distinct profile specific to children and adolescents who have been diagnosed with bipolar disorder. The objective of this study was to examine whether bipolar disorder youth with depression exhibit the "CBCL-Juvenile bipolar disorder phenotype." METHODS: Thirty-two adolescents, ages 12-18 years, with a depressive episode associated with bipolar I disorder were recruited, and their primary caregivers completed the CBCL. RESULTS: Only the internalizing subscale (mean=70.2, SD=9.7) and total score (mean=71.5, SD=8.9) reached clinical significance (>70). Moreover, the CBCL-JBD profile scores of our subjects (204.6, SD=27.5) did not reach clinical significance (>210). LIMITATIONS: Our subjects differed demographically from those in studies that have confirmed the CBCL-Juvenile bipolar disorder phenotype with regards to sex, age and ADHD comorbidity, thus limiting the interpretability of our comparisons with other studies. Furthermore, our investigation involved a small sample size and did not include a control group, which should be addressed in future studies. CONCLUSIONS: The results of our study suggest that the CBCL-JBD profile is not characteristic of depressed youth with bipolar disorder. Better assessment tools for making an accurate and efficient diagnosis of bipolar disorder are needed so that appropriate treatment can be implemented and significant morbidity and mortality are minimized.


Assuntos
Transtorno Bipolar/psicologia , Lista de Checagem , Depressão/epidemiologia , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Comorbidade , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes
17.
J Acoust Soc Am ; 131(2): 1391-400, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22352512

RESUMO

The voice source is dominated by aeroacoustic sources downstream of the glottis. In this paper an investigation is made of the contribution to voiced speech of secondary sources within the glottis. The acoustic waveform is ultimately determined by the volume velocity of air at the glottis, which is controlled by vocal fold vibration, pressure forcing from the lungs, and unsteady backreactions from the sound and from the supraglottal air jet. The theory of aerodynamic sound is applied to study the influence on the fine details of the acoustic waveform of "potential flow" added-mass-type glottal sources, glottis friction, and vorticity either in the glottis-wall boundary layer or in the portion of the free jet shear layer within the glottis. These sources govern predominantly the high frequency content of the sound when the glottis is near closure. A detailed analysis performed for a canonical, cylindrical glottis of rectangular cross section indicates that glottis-interior boundary/shear layer vortex sources and the surface frictional source are of comparable importance; the influence of the potential flow source is about an order of magnitude smaller.


Assuntos
Glote/anatomia & histologia , Acústica da Fala , Voz/fisiologia , Feminino , Glote/fisiologia , Humanos , Masculino , Modelos Biológicos , Pressão , Reologia , Prega Vocal/anatomia & histologia , Prega Vocal/fisiologia
18.
J Fluid Mech ; 672: 428-450, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21666824

RESUMO

An analysis is made of the sound generated by the time-dependent throttling of a nominally steady stream of air through a small orifice into a flow-through resonant cavity. This is exemplified by the production of voiced speech, where air from the lungs enters the vocal tract through the glottis at a time variable volume flow rate Q(t) controlled by oscillations of the glottis cross-section. Voicing theory has hitherto determined Q from a heuristic, reduced complexity 'Fant' differential equation (G. Fant, Acoustic Theory of Speech Production, 1960). A new self-consistent, integro-differential form of this equation is derived in this paper using the theory of aerodynamic sound, with full account taken of the back-reaction of the resonant tract on the glottal flux Q. The theory involves an aeroacoustic Green's function (G) for flow-surface interactions in a time-dependent glottis, so making the problem non-self-adjoint. In complex problems of this type it is not usually possible to obtain G in an explicit analytic form. The principal objective of the paper is to show how the Fant equation can still be derived in such cases from a consideration of the equation of aerodynamic sound and from the adjoint of the equation governing G in the neighbourhood of the 'throttle'. The theory is illustrated by application to the canonical problem of throttled flow into a Helmholtz resonator.

19.
J Sound Vib ; 330(13): 3123-3140, 2011 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-21603054

RESUMO

An analysis is made of the fluid-structure interactions involved in the production of voiced speech. It is usual to avoid time consuming numerical simulations of the aeroacoustics of the vocal tract and glottis by the introduction of Fant's 'reduced complexity' equation for the glottis volume velocity Q (G. Fant, Acoustic Theory of Speech Production, Mouton, The Hague 1960). A systematic derivation is given of Fant's equation based on the nominally exact equations of aerodynamic sound. This can be done with a degree of approximation that depends only on the accuracy with which the time-varying flow geometry and surface-acoustic boundary conditions can be specified, and replaces Fant's original 'lumped element' heuristic approach. The method determines all of the effective 'source terms' governing Q. It is illustrated by consideration of a simplified model of the vocal system involving a self-sustaining single-mass model of the vocal folds, that uses free streamline theory to account for surface friction and flow separation within the glottis. Identification is made of a new source term associated with the unsteady vocal fold drag produced by their oscillatory motion transverse to the mean flow.

20.
Eur J Clin Nutr ; 65(6): 764-7, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21427740

RESUMO

A service evaluation of a pilot of a family-based behavioural management group programme for childhood obesity was conducted in a community setting in the United Kingdom. A total of 17 families with children aged 7.5-14 years completed the programme, which was delivered in 15 sessions over 6 months. Behavioural and psychological measures and age- and sex-adjusted z-body mass index (BMI) were assessed before and after programme. z-BMI was maintained. There was a significant increase in the amount of high-fibre foods and a decrease in the amount of low-fibre foods consumed and in sedentary behaviours. There were significant decreases in depression, abnormal dieting behaviour and bulimia and food preoccupation, and an increase in self-worth related to physical appearance. These positive behavioural and psychological changes suggest that this is a promising programme.


Assuntos
Terapia Comportamental/métodos , Bulimia/terapia , Comportamento Infantil , Depressão/terapia , Fibras na Dieta/administração & dosagem , Obesidade/terapia , Comportamento Sedentário , Adolescente , Imagem Corporal , Índice de Massa Corporal , Bulimia/complicações , Criança , Dieta Redutora , Feminino , Processos Grupais , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Obesidade/complicações , Obesidade/psicologia , Comportamento Obsessivo , Características de Residência , Autoimagem , Resultado do Tratamento , Reino Unido
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