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1.
Food Chem ; 304: 125403, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31479993

RESUMO

Current information on the links between the chemistry and hedonic liking of edible mushrooms is scarce. In this study, 84 consumers evaluated the appearance, odor, taste, texture and overall liking of samples of Nordic edible wild mushroom species. Subsequently, multivariate models on the effects of non-volatile compounds, odor-contributing volatile compounds, sensory attributes and hedonic likings were created. The non-volatile compounds were measured with quantitative NMR. The five studied mushroom species were different in their sugar and acid contents. Three consumer clusters were found with species*cluster interactions. Correlations with sensory attributes and chemical components were found, and the multivariate models indicated predictor attributes for each consumer cluster. The results indicate that the sensory properties could be correlated to both volatile and non-volatile compounds, there are consumer clusters with differing likings as regards mushrooms, and these clusters are heterogenic groups with no simple factors such as age explaining their liking scores.

2.
Environ Sci Technol ; 53(21): 12357-12365, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31553886

RESUMO

We use a real-time temperature-programmed desorption chemical-ionization mass spectrometer (FIGAERO-CIMS) to measure particle-phase composition and volatility of nucleated particles, studying pure α-pinene oxidation over a wide temperature range (-50 °C to +25 °C) in the CLOUD chamber at CERN. Highly oxygenated organic molecules are much more abundant in particles formed at higher temperatures, shifting the compounds toward higher O/C and lower intrinsic (300 K) volatility. We find that pure biogenic nucleation and growth depends only weakly on temperature. This is because the positive temperature dependence of degree of oxidation (and polarity) and the negative temperature dependence of volatility counteract each other. Unlike prior work that relied on estimated volatility, we directly measure volatility via calibrated temperature-programmed desorption. Our particle-phase measurements are consistent with gas-phase results and indicate that during new-particle formation from α-pinene oxidation, gas-phase chemistry directly determines the properties of materials in the condensed phase. We now have consistency between measured gas-phase product concentrations, product volatility, measured and modeled growth rates, and the particle composition over most temperatures found in the troposphere.

3.
Food Res Int ; 109: 526-536, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29803480

RESUMO

Edible mushrooms are a global food with a history of consumption spanning several millennia. However, studies utilizing modern sensory methods on mushrooms are still scarce. In this study, the sensory properties of Nordic edible mushrooms were analyzed by two methods. In the sensory profile, sous vide processed wild mushroom species Cantharellus cibarius, Craterellus tubaeformis, Boletus edulis, and Lactarius camphoratus were studied with cultivated Agaricus bisporus as a control species. The sensory profile consisted of 18 descriptors, and the 5 mushrooms differed from each other in all of them. Only B. edulis and A. bisporus were linked to typical mushroom-like odor. In projective mapping, consumers evaluated blanched wild C. cibarius, C. tubaeformis and Suillus variegatus as well as cultivated Lentinula edodes and both blanched and fresh A. bisporus based on odor and on flavor. The consumers intuitively grouped the samples into three groups: wild, fresh cultivated and processed cultivated mushrooms. Wild mushrooms had a high odor intensity and various odor descriptions but a low flavor intensity. Cultivated mushrooms had opposite descriptions. Both tests showed differences in the sensory descriptors between the cultivated and wild mushrooms with the former linked to typical 'mushroom', indicating the importance and need for descriptive profiles for different mushroom types.

4.
Food Chem ; 247: 23-28, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29277224

RESUMO

Edible mushrooms are valued because of their umami taste and good nutritional values. Free amino acids, 5'-nucleotides and nucleosides were analyzed from four Nordic forest mushroom species (Lactarius camphoratus, Boletus edulis, Cantharellus cibarius, Craterellus tubaeformis) using high precision liquid chromatography analysis. To our knowledge, these taste components were studied for the first time from Craterellus tubaeformis and Lactarius camphoratus. The focus was on the umami amino acids and 5'-nucleotides. The free amino acid and 5'-nucleotide/nucleoside contents of studied species differed from each other. In all studied samples, umami amino acids were among five major free amino acids. The highest concentration of umami amino acids was on L. camphoratus whereas B. edulis had the highest content of sweet amino acids and C. cibarius had the highest content of bitter amino acids. The content of umami enhancing 5'-nucleotides were low in all studied species.


Assuntos
Agaricales/química , Aminoácidos/análise , Nucleosídeos/análise , Basidiomycota/química , Cromatografia Líquida , Finlândia , Análise de Alimentos , Florestas , Ácido Glutâmico/análise , Nucleotídeos/análise , Paladar
5.
Sci Rep ; 7: 45707, 2017 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-28374761

RESUMO

Solar eclipses provide unique possibilities to investigate atmospheric processes, such as new particle formation (NPF), important to the global aerosol load and radiative balance. The temporary absence of solar radiation gives particular insight into different oxidation and clustering processes leading to NPF. This is crucial because our mechanistic understanding on how NPF is related to photochemistry is still rather limited. During a partial solar eclipse over Finland in 2015, we found that this phenomenon had prominent effects on atmospheric on-going NPF. During the eclipse, the sources of aerosol precursor gases, such as sulphuric acid and nitrogen- containing highly oxidised organic compounds, decreased considerably, which was followed by a reduced formation of small clusters and nanoparticles and thus termination of NPF. After the eclipse, aerosol precursor molecule concentrations recovered and re-initiated NPF. Our results provide direct evidence on the key role of the photochemical production of sulphuric acid and highly oxidized organic compounds in maintaining atmospheric NPF. Our results also explain the rare occurrence of this phenomenon under dark conditions, as well as its seemingly weak connection with atmospheric ions.

6.
Nature ; 539(7629): 416-419, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27776357

RESUMO

The nucleation of atmospheric vapours is an important source of new aerosol particles that can subsequently grow to form cloud condensation nuclei in the atmosphere. Most field studies of atmospheric aerosols over continents are influenced by atmospheric vapours of anthropogenic origin (for example, ref. 2) and, in consequence, aerosol processes in pristine, terrestrial environments remain poorly understood. The Amazon rainforest is one of the few continental regions where aerosol particles and their precursors can be studied under near-natural conditions, but the origin of small aerosol particles that grow into cloud condensation nuclei in the Amazon boundary layer remains unclear. Here we present aircraft- and ground-based measurements under clean conditions during the wet season in the central Amazon basin. We find that high concentrations of small aerosol particles (with diameters of less than 50 nanometres) in the lower free troposphere are transported from the free troposphere into the boundary layer during precipitation events by strong convective downdrafts and weaker downward motions in the trailing stratiform region. This rapid vertical transport can help to maintain the population of particles in the pristine Amazon boundary layer, and may therefore influence cloud properties and climate under natural conditions.


Assuntos
Aerossóis/análise , Chuva , Aerossóis/química , Biomassa , Brasil , Fogo , Tamanho da Partícula , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química
7.
Science ; 339(6122): 943-6, 2013 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-23430652

RESUMO

Atmospheric nucleation is the dominant source of aerosol particles in the global atmosphere and an important player in aerosol climatic effects. The key steps of this process occur in the sub-2-nanometer (nm) size range, in which direct size-segregated observations have not been possible until very recently. Here, we present detailed observations of atmospheric nanoparticles and clusters down to 1-nm mobility diameter. We identified three separate size regimes below 2-nm diameter that build up a physically, chemically, and dynamically consistent framework on atmospheric nucleation--more specifically, aerosol formation via neutral pathways. Our findings emphasize the important role of organic compounds in atmospheric aerosol formation, subsequent aerosol growth, radiative forcing and associated feedbacks between biogenic emissions, clouds, and climate.

8.
Nat Protoc ; 7(9): 1651-67, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22899333

RESUMO

The formation of new atmospheric aerosol particles and their subsequent growth have been observed frequently at various locations all over the world. The atmospheric nucleation rate (or formation rate) and growth rate (GR) are key parameters to characterize the phenomenon. Recent progress in measurement techniques enables us to measure atmospheric nucleation at the size (mobility diameter) of 1.5 (±0.4) nm. The detection limit has decreased from 3 to 1 nm within the past 10 years. In this protocol, we describe the procedures for identifying new-particle-formation (NPF) events, and for determining the nucleation, formation and growth rates during such events under atmospheric conditions. We describe the present instrumentation, best practices and other tools used to investigate atmospheric nucleation and NPF at a certain mobility diameter (1.5, 2.0 or 3.0 nm). The key instruments comprise devices capable of measuring the number concentration of the formed nanoparticles and their size, such as a suite of modern condensation particle counters (CPCs) and air ion spectrometers, and devices for characterizing the pre-existing particle number concentration distribution, such as a differential mobility particle sizer (DMPS). We also discuss the reliability of the methods used and requirements for proper measurements and data analysis. The time scale for realizing this procedure is 1 year.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Atmosfera/análise , Técnicas de Química Analítica/métodos , Monitoramento Ambiental/métodos , Material Particulado/análise , Técnicas de Química Analítica/instrumentação , Monitoramento Ambiental/instrumentação , Tamanho da Partícula
9.
Infant Behav Dev ; 32(3): 305-11, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19446341

RESUMO

The aim of the study was to assess attachment representations in mothers of preterm infants using the Working Model of Child Interview (WMCI) at the 12 months of the infant's corrected age. In addition, the relation between WMCI representation categories and the Edinburgh Postnatal Depression Scale score at 6 months of the infant's corrected age was studied. There were 38 mothers of preterm infants (<1500 g or <32 gestational weeks) and 45 mothers of full-term infants. The results showed no differences between the study groups in the distribution of the three main representation categories (balanced, disengaged and distorted). However, there were qualitative differences in representations between the groups. Furthermore, maternal depression symptoms were associated with distorted representation category. We suggest that despite the qualitative differences in the mothers' representations, mothers of preterm infants are as likely to form balanced attachments with their infants as mothers of full-term infants.


Assuntos
Recém-Nascido Prematuro , Relações Mãe-Filho , Mães/psicologia , Adolescente , Adulto , Análise de Variância , Depressão , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Testes Neuropsicológicos , Adulto Jovem
10.
Early Hum Dev ; 84(4): 257-67, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17707118

RESUMO

OBJECTIVES: The aim of this study was to evaluate associations between infant crying, holding and mother-infant interaction. METHODS: The study groups included 30 firstborn Finnish preterm infants (<1501 g or <32 weeks), and their 36 full-term controls. Caregiver's holding and infant's crying behavior was assessed using Baby Day Diary at 5 months of corrected age. The quality of mother-infant interaction was assessed using PC-ERA at 6 and 12 months of corrected age. RESULTS: The results showed that longer duration of holding in home environment was associated with better quality of mother-infant interaction at 6 and 12 months of corrected age in preterm infants. Preterm infants cried more often and were held more than full-term infants. The frequency of crying was associated with the duration of holding in preterm infants. Mother-infant interaction was comparable between the groups of preterm and full-term infants. CONCLUSIONS: Our results underline the importance of caregiver's physical closeness for the quality of the mother-infant interaction in preterm infants. Prematurity itself does not necessary affect the quality of mother-infants interaction in a non-risk population.


Assuntos
Cuidado do Lactente/psicologia , Recém-Nascido Prematuro/fisiologia , Relações Mãe-Filho , Mães/psicologia , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Choro/fisiologia , Choro/psicologia , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro/psicologia , Masculino
11.
Clin Child Psychol Psychiatry ; 12(3): 421-36, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17953129

RESUMO

This article describes the development of a collaborative relationship between a child psychiatry clinic and an adult oncology clinic within a university hospital. The interest of the child psychiatry clinic was to pay attention to children of parents with cancer, and to propose an intervention to support them. A child-centred family counselling model was designed for this purpose. The preparation, implementation, and results of this project are described. Positive results, as well as mistakes and failures are discussed, and recommendations are made regarding this kind of collaboration.


Assuntos
Filho de Pais Incapacitados/psicologia , Comportamento Cooperativo , Terapia Familiar/organização & administração , Comunicação Interdisciplinar , Neoplasias/psicologia , Serviço Hospitalar de Oncologia , Unidade Hospitalar de Psiquiatria , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Finlândia , Implementação de Plano de Saúde , Humanos , Relações Interprofissionais , Masculino , Modelos Organizacionais , Neoplasias/terapia
12.
Science ; 318(5847): 89-92, 2007 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-17761851

RESUMO

Atmospheric aerosol formation is known to occur almost all over the world, and the importance of these particles to climate and air quality has been recognized. Although almost all of the processes driving aerosol formation take place below a particle diameter of 3 nanometers, observations cover only larger particles. We introduce an instrumental setup to measure atmospheric concentrations of both neutral and charged nanometer-sized clusters. By applying the instruments in the field, we come to three important conclusions: (i) A pool of numerous neutral clusters in the sub-3 nanometer size range is continuously present; (ii) the processes initiating atmospheric aerosol formation start from particle sizes of approximately 1.5 nanometers; and (iii) neutral nucleation dominates over the ion-induced mechanism, at least in boreal forest conditions.

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