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1.
Phys Chem Chem Phys ; 24(37): 22716-22723, 2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36106954

RESUMEN

We report a combined experimental and computational study of carbon dioxide activation at gas-phase Ho+ and HoO+ centres. Infrared action spectra of Ho(CO2)n+ and [HoO(CO2)n]+ ion-molecule complexes have been recorded in the spectral region 1700-2400 cm-1 and assigned by comparison with simulated spectra of energetically low-lying structures determined by density functional theory. Little by way of activation is observed in Ho(CO2)n+ complexes with CO2 binding end-on to the Ho+ ion. By contrast, all [HoO(CO2)n]+ complexes n ≥ 3 show unambiguous evidence for formation of a carbonate radical anion moiety, . The signature of this structure, a new vibrational band observed around 1840 cm-1 for n = 3, continues to red-shift monotonically with each successive CO2 ligand binding with net charge transfer from the ligand rather than the metal centre.

2.
Sci Total Environ ; 929: 172634, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38643883

RESUMEN

Chicken fillets, predominantly encased in disposable plastic packaging, represent a common perishable commodity frequently found in the shopping baskets of British consumers, with an annual slaughter exceeding 1.1 billion chickens. The associated environmental implications are of considerable significance. However, a noticeable gap exists concerning the household-level ramifications of chicken meat consumption, which remains a prominent driver (165 kg CO2eyr-1 per capita) of environmental impacts in the United Kingdom (UK). This study's primary objective is to integrate Life Cycle Assessment (LCA) methodology with insights derived from a spectrum of interventions simulated within the Household Simulation Model (HHSM). The interventions that are simulated are influenced by various consumer behaviours related to the purchase, consumption, storage and disposal of chicken fillets. The overarching aim is to provide a comprehensive understanding of the environmental consequences associated with each intervention. The research encompasses eight distinct household archetypes and the UK average, with a focus on discerning differences in their environmental influence. The introduction of shelf-life extension measures leads to a reduction in the overall environmental impacts (in µPt), with reductions ranging from 1 % to 18 %. Concurrently, waste treatment's environmental burdens can be curtailed by 9 % to 69 % for the UK average. Of the 12 interventions tested, the intervention that combines a one-day extension in the shelf life of open packs and a three-day extension for unopened packs leads to the greatest reduction in environmental impacts, at 18 % for the entire process and 69 % for the waste treatment. This intervention is estimated to yield annual reductions of 130,722 t of CO2 emissions across the entire process and 34,720 t of CO2 emissions from waste treatment, as compared to the default scenario. These findings demonstrate the importance of integrating consumer behaviour, food waste, and packaging considerations within the domain of food LCA research.


Asunto(s)
Conservación de los Recursos Naturales , Reino Unido , Animales , Conservación de los Recursos Naturales/métodos , Pollos , Ambiente , Comportamiento del Consumidor , Composición Familiar , Modelos Teóricos
3.
J Voice ; 26(6): 734-41, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22717492

RESUMEN

OBJECTIVE: To clinically evaluate changes in vocal fold vibration and voice production caused by voice therapy in hoarseness resulting from contact granuloma. DESIGN: Single-subject before-after prospective study using multiple measures of vocal function. A 6-week program of vocal function exercises (VFEs) was conducted using multiple assessments of vocal function to identify and measure the changes pre- and posttreatment, in a 51-year-old male with unilateral contact granuloma. Multiple outcome measures were recorded. High-speed digital imaging (HSDI) measures of voice onset time (milliseconds), open quotient, speed quotient, maximum amplitude, peak closing velocity, peak-to-average opening velocity, and peak-to-average closing velocity were derived from motion data. Acoustic measures of maximum phonation duration (seconds), noise-to-harmonic ratio, average fundamental frequency (hertz), the lowest fundamental frequency (hertz), and the highest fundamental frequency (hertz); aerodynamic measures of expiratory volume (milliliter) and mean expiratory airflow (liter/second); stroboscopic measures of glottal closure and phase closure; and perceptual assessment of voice quality (total score) using the Consensus Auditory-Perceptual Evaluation of Voice were obtained. RESULTS: Stroboscopic, acoustic, aerodynamic, and audioperceptual measures were minimally informative related to pre- and posttreatment vocal function in a patient with contact granuloma. HSDI measures provided multiple physiologic and kinematic measures demonstrating pre- and posttreatment efficiency of vocal function, including vibratory motion, closure, and impact stress. CONCLUSION: The results have implications for the use of high-speed imaging to identify and measure change in phonatory physiology in patients with contact granuloma. Changes in phonatory physiology support the use of voice therapy techniques, such as VFEs that facilitate a semioccluded vocal tract for treatment of contact granuloma.


Asunto(s)
Disfonía/terapia , Granuloma Laríngeo/complicaciones , Ronquera/diagnóstico , Ronquera/terapia , Fonación , Pliegues Vocales/fisiopatología , Calidad de la Voz , Entrenamiento de la Voz , Acústica , Fenómenos Biomecánicos , Disfonía/diagnóstico , Disfonía/etiología , Disfonía/fisiopatología , Ronquera/etiología , Ronquera/fisiopatología , Humanos , Quimografía , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Procesamiento de Señales Asistido por Computador , Acústica del Lenguaje , Percepción del Habla , Medición de la Producción del Habla , Estroboscopía , Factores de Tiempo , Resultado del Tratamiento , Vibración
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