78 research outputs found
On the Functional Relationship Between Fluorescence and Photochemical Yields in Complex Evergreen Needleleaf Canopies
Recent advancements in understanding remotely sensed solarâinduced chlorophyll fluorescence often suggest a linear relationship with gross primary productivity at large spatial scales. However, the quantum yields of fluorescence and photochemistry are not linearly related, and this relationship is largely driven by irradiance. This raises questions about the mechanistic basis of observed linearity from complex canopies that experience heterogeneous irradiance regimes at subcanopy scales. We present empirical data from two evergreen forest sites that demonstrate a nonlinear relationship between needleâscale observations of steadyâstate fluorescence yield and photochemical yield under ambient irradiance. We show that accounting for subcanopy and diurnal patterns of irradiance can help identify the physiological constraints on needleâscale fluorescence at 70â80% accuracy. Our findings are placed in the context of how solarâinduced chlorophyll fluorescence observations from spaceborne sensors relate to diurnal variation in canopyâscale physiology
Feminist health psychology and abortion : towards a politics of transversal relations of commonality
In 1992 Speckhard and Rue argued in the Journal of Social Issues for the recognition of a diagnostic category, post-abortion syndrome (PAS). This term was first used in 1981 by Vincent Rue in testimony to the American Congress, but was only formalised in a published paper a decade later. Speckhard and Rue (1992) posit that abortion is a psychosocial stressor that may cause mild distress through to severe trauma, creating the need for a continuum of categories, these being post-abortion distress, post-abortion syndrome and post-abortion psychosis. PAS, which is the main focus of their paper, and which has taken root in some professional language as well as lay anti-abortion discourse, is described as a type of post-traumatic stress disorder
Blue intensity from a tropical coniferâs annual rings for climate reconstruction : an ecophysiological perspective
This research was funded by the National Science Foundation of the USA research grants AGS 12-03818 and AGS 13-03976, with additional funding from the Lamont-Doherty Earth Observatoryâs Climate Center and Climate and Life initiatives.We developed Blue Intensity (BI) measurements from the crossdated ring sequences of Fokienia hodginsii (of the family Cupressaceae) from central Vietnam. BI has been utilized primarily as an indirect proxy measurement of latewood (LW) density of conifers (i.e., LWBI) from high latitude, temperature-limited boreal forests. As such, BI closely approximates maximum latewood density (MXD) measurements made from soft x-ray. The less commonly used earlywood (EW) BI (EWBI) represents the minimum density of EW and is influenced by the lighter pixels from the vacuoles or lumens of cells. The correlation of our BI measurements with climate, strongest for EWBI, rivals that for total ring width (RW), and we demonstrate that it can be successfully employed as an independent predictor for reconstruction models. EWBI exhibits robust spatial correlations with winter and spring land temperature, sea surface temperature (SST) over the regional domain of ENSO, and the Standardized Precipitation Evapotranspiration Index (SPEI) over Indochina. However, in order to mitigate the effects of color changes at the heartwood â sapwood boundary we calculated ÎBI (EWBI-LWBI), and it too exhibits a significant (pâŻ<âŻ0.05), temporally stable response to prior autumn (Oct-Nov) rainfall and winter (December to April) dry season temperature. We interpret this response as reflecting a potential cavitation defense by reducing lumen diameter as a means to safeguard hydraulic conductivity in the stem, and to prevent the xylem from imploding due to negative pressure. This study has wide implications for the further use of BI from the global tropics, though it is unclear how many tropical tree species will be appropriate for use. It seems very likely that other wood anatomical measurements can be combined with BI and RW for climate reconstruction.Publisher PDFPeer reviewe
Use of psychotropic drugs before pregnancy and the risk for induced abortion: population-based register-data from Finland 1996-2006
<p>Abstract</p> <p>Background</p> <p>Some, though not all studies have reported an increased risk for mental health problems after an induced abortion. Problems with design and data have compromised these studies and the generalisation of their results.</p> <p>Methods</p> <p>The Finnish Medication and Pregnancy database (N = 622 671 births and 114 518 induced abortions for other than fetal reasons) in 1996-2006 was utilised to study the use of psychotropic drugs in the three months before a pregnancy ending in a birth or an induced abortion.</p> <p>Results</p> <p>In total 2.1% of women with a birth and 5.1% of women with an induced abortion had used a psychotropic medicine 0-3 months before pregnancy. Psychotropic drug users terminated their pregnancies (30.9%) more often than other pregnant women (15.5%). Adjustment for background characteristics explained one third of this elevated risk, but the risk remained significantly increased among users of psychotropic medicine (OR 1.94, 95% confidence intervals 1.87-2.02). A similar risk was found for first pregnancies (30.1% vs. 18.9%; adjusted OR 1.53, 95% confidence intervals 1.42-1.65). The rate for terminating pregnancy was the highest for women using hypnotics and sedatives (35.6% for all pregnancies and 29.1% for first pregnancies), followed by antipsychotics (33.9% and 36.0%) and antidepressants (32.0% and 32.1%).</p> <p>Conclusions</p> <p>The observed increased risk for induced abortion among women with psychotropic medication highlighs the importance to acknowledge the mental health needs of women seeking an induced abortion. Further studies are needed to establish the impact of pre-existing differences in mental health on mental health outcomes of induced abortions compared to outcomes of pregnancies ending in a birth.</p
The effect of different cardiovascular risk presentation formats on intentions, understanding and emotional affect: a randomised controlled trial using a web-based risk formatter (protocol)
Background
The future risk of heart disease can be predicted with increasing precision. However, more research is needed into how this risk is conveyed and presented. The aim of this study is to compare the effects of presenting cardiovascular risk in different formats on individuals' intention to change behaviour to reduce risk, understanding of risk information and emotional affect.
Methods/design
A randomised controlled trial comprising four arms, with a between subjects design will be performed. There will be two intervention groups and two control groups. The first control comprises a pre-intervention questionnaire and presents risk in a bar graph format. The second control presents risk in a bar graph format without pre-intervention questionnaire. These two control groups are to account for the potential Hawthorne effect of thinking about cardiovascular risk before viewing actual risk. The two intervention groups comprise presenting risk in either a pictogram or metonym format (image depicting seriousness of having a myocardial infarction). 800 individuals' aged between 45 and 64 years, who have not been previously diagnosed with heart disease and have access to a computer with internet, will be given a link to a website comprising a risk calculator and electronic questionnaires. 10-year risk of having a coronary heart disease event will be assessed and presented in one of the three formats. A post-intervention questionnaire will be completed after viewing the risk format. Main outcome measures are (i) intention to change behaviour, (ii) understanding of risk information, (iii) emotional affect and (iv) worry about future heart disease. Secondary outcomes are the sub-components of the theory of planned behaviour: attitudes, perceived behavioural control and subjective norms.
Discussion
Having reviewed the literature, we are not aware of any other studies which have used the assessment of actual risk, in a trial to compare different graphical cardiovascular risk presentation formats. This trial will provide data about which graphical cardiovascular risk presentation format is most effective in encouraging behaviour change to reduce cardiovascular risk.
Trial registration
Current Controlled Trials ISRCTN9131931
Sun Protection Intervention for Highway Workers: Long-Term Efficacy of UV Photography and Skin Cancer Information on Menâs Protective Cognitions and Behavior
The risk for skin cancer is increased among older males and outdoor workers who have high levels of ultraviolet (UV) exposure.
This study was designed to examine the long-term efficacy of UV photography interventions on male outdoor workers, the potential mediators of its impact, and the efficacy of UV photography and skin cancer vs. aging information with this population.
One hundred forty-eight male outdoor workers were randomly assigned to one of four intervention conditions or a control condition in a two by two plus one factorial design. The men in the intervention conditions received or did not receive a UV photo of their face and watched either a photoaging or skin cancer educational video. Participants completed pre-intervention, immediate post-intervention, and 2-month and 1-year follow-up assessments.
Analysis of covariance and structural equation modeling revealed that participants in the UV photography and cancer information interventions reported higher levels of sun protection cognitions, which were significant partial mediators of increases in sun protection behaviors and decreases in skin color.
This study provides evidence for effective sun protection interventions on male outdoor workers that may help reduce skin cancer risk
A reporting format for leaf-level gas exchange data and metadata
Leaf-level gas exchange data support the mechanistic understanding of plant fluxes of carbon and water. These fluxes inform our understanding of ecosystem function, are an important constraint on parameterization of terrestrial biosphere models, are necessary to understand the response of plants to global environmental change, and are integral to efforts to improve crop production. Collection of these data using gas analyzers can be both technically challenging and time consuming, and individual studies generally focus on a small range of species, restricted time periods, or limited geographic regions. The high value of these data is exemplified by the many publications that reuse and synthesize gas exchange data, however the lack of metadata and data reporting conventions make full and efficient use of these data difficult. Here we propose a reporting format for leaf-level gas exchange data and metadata to provide guidance to data contributors on how to store data in repositories to maximize their discoverability, facilitate their efficient reuse, and add value to individual datasets. For data users, the reporting format will better allow data repositories to optimize data search and extraction, and more readily integrate similar data into harmonized synthesis products. The reporting format specifies data table variable naming and unit conventions, as well as metadata characterizing experimental conditions and protocols. For common data types that were the focus of this initial version of the reporting format, i.e., survey measurements, dark respiration, carbon dioxide and light response curves, and parameters derived from those measurements, we took a further step of defining required additional data and metadata that would maximize the potential reuse of those data types. To aid data contributors and the development of data ingest tools by data repositories we provided a translation table comparing the outputs of common gas exchange instruments. Extensive consultation with data collectors, data users, instrument manufacturers, and data scientists was undertaken in order to ensure that the reporting format met community needs. The reporting format presented here is intended to form a foundation for future development that will incorporate additional data types and variables as gas exchange systems and measurement approaches advance in the future. The reporting format is published in the U.S. Department of Energy's ESS-DIVE data repository, with documentation and future development efforts being maintained in a version control system
Depression and termination of pregnancy (induced abortion) in a national cohort of young Australian women: the confounding effect of women's experience of violence
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