Methodological guidelines for LCA of French agricultural products

This article outlines the methodological guidelines that will be applied in the framework of the program Agri-BALYSE in order to compile life cycle inventories for about 110 French agricultural products. Special emphasis will be given on the treatment and the capture of the four main sources of variability for agricultural production systems: Variability due to differing natural production conditions, variability due to different production methods, variability due to different agricultural practices within a given production method and variability due to uncertainty of measurements. The guidelines are compiled in the Agri- BALYSE data collection guide which will be available end of summer 2011. Given the strategic importance of the Agri-BALYSE database, the data collection guide may become a national standard for LCA of agricultural products in France. (Résumé d'auteur

Temporal Variability and Stability in Infant-Directed Sung Speech: Evidence for Language-specific Patterns.

In this paper, sung speech is used as a methodological tool to explore temporal variability in the timing of word-internal consonants and vowels. It is hypothesized that temporal variability/stability becomes clearer under the varying rhythmical conditions induced by song. This is explored crosslinguistically in German – a language that exhibits a potential vocalic quantity distinction – and the non-quantity languages French and Russian. Songs by non-professional singers, i.e. parents that sang to their infants aged 2 to 13 months in a non-laboratory setting, were recorded and analyzed. Vowel and consonant durations at syllable contacts of trochaic word types with ¦CVCV or ¦CVːCV structure were measured under varying rhythmical conditions. Evidence is provided that in German non-professional singing, the two syllable structures can be differentiated by two distinct temporal variability patterns: vocalic variability (and consonantal stability) was found to be dominant in ¦CVːCV structures whereas consonantal variability (and vocalic stability) was characteristic for ¦CVCV structures. In French and Russian, however, only vocalic variability seemed to apply. Additionally, findings suggest that the different temporal patterns found in German were also supported by the stability pattern at the tonal level. These results point to subtle (supra) segmental timing mechanisms in sung speech that affect temporal targets according to the specific prosodic nature of the language in question

Evaluation of air-displacement plethysmography in children aged 5-7 years using a three-component model of body composition

The aim of the present study was to evaluate air-displacement plethysmography (ADP) in children aged 5-7 years. Body-composition measurements were obtained by ADP, H-2 dilution and anthropometry in twenty-eight children. Calculation of body volume by ADP was undertaken using adult and children's equations for predicting lung volume and surface area. Fat-free mass (FFM) was calculated using a three-component model. Measured FFM hydration was then compared with values from the reference child. Differences between measured and reference hydration were back-extrapolated, to calculate the error in ADP that would account for any disagreement. Propagation of error was used to distinguish the contributions of methodological precision and biological variability to total hydration variability. The use of children's equations influenced the results for lung volume but not surface area. The mean difference between measured and reference hydration was 0.6 (SD 1.7) % (P<0.10), equivalent to an error in body volume of 0.04 (So 0.20) litres (P<0.30), and in percentage fat of 0.4 (SD 1.9) (P<0.28). The limits of agreement in individuals could be attributed to methodological precision and biological variability in hydration. It is concluded that accuracy of ADP was high for the whole group, with a mean bias of <0.5% fat using the three-component model, and after taking into account biological variability in hydration, the limits of agreement were around 2 % fat in individuals. Paediatric rather than adult equations for lung volume estimation should be used

Dealing with missing standard deviation and mean values in meta-analysis of continuous outcomes: a systematic review

Background: Rigorous, informative meta-analyses rely on availability of appropriate summary statistics or individual participant data. For continuous outcomes, especially those with naturally skewed distributions, summary information on the mean or variability often goes unreported. While full reporting of original trial data is the ideal, we sought to identify methods for handling unreported mean or variability summary statistics in meta-analysis. Methods: We undertook two systematic literature reviews to identify methodological approaches used to deal with missing mean or variability summary statistics. Five electronic databases were searched, in addition to the Cochrane Colloquium abstract books and the Cochrane Statistics Methods Group mailing list archive. We also conducted cited reference searching and emailed topic experts to identify recent methodological developments. Details recorded included the description of the method, the information required to implement the method, any underlying assumptions and whether the method could be readily applied in standard statistical software. We provided a summary description of the methods identified, illustrating selected methods in example meta-analysis scenarios. Results: For missing standard deviations (SDs), following screening of 503 articles, fifteen methods were identified in addition to those reported in a previous review. These included Bayesian hierarchical modelling at the meta-analysis level; summary statistic level imputation based on observed SD values from other trials in the meta-analysis; a practical approximation based on the range; and algebraic estimation of the SD based on other summary statistics. Following screening of 1124 articles for methods estimating the mean, one approximate Bayesian computation approach and three papers based on alternative summary statistics were identified. Illustrative meta-analyses showed that when replacing a missing SD the approximation using the range minimised loss of precision and generally performed better than omitting trials. When estimating missing means, a formula using the median, lower quartile and upper quartile performed best in preserving the precision of the meta-analysis findings, although in some scenarios, omitting trials gave superior results. Conclusions: Methods based on summary statistics (minimum, maximum, lower quartile, upper quartile, median) reported in the literature facilitate more comprehensive inclusion of randomised controlled trials with missing mean or variability summary statistics within meta-analyses

Value and efficacy of transcranial direct current stimulation in the rehabilitation of neurocognitive disorders: A critical review since 2000.

open3siNon-invasive brain stimulation techniques, including transcranial direct current stimulation (t-DCS) have been used in the rehabilitation of cognitive function in a spectrum of neurological disorders. The present review outlines methodological communalities and differences of t-DCS procedures in neurocognitive rehabilitation. We consider the efficacy of tDCS for the management of specific cognitive deficits in four main neurological disorders by providing a critical analysis of recent studies that have used t-DCS to improve cognition in patients with Parkinson’s Disease, Alzheimer’s Disease, Hemi-spatial Neglect and Aphasia. The evidence from this innovative approach to cognitive rehabilitation suggests that tDCS can influence cognition. However, the results show a high variability between studies both on the methodological approach adopted and the cognitive functions aspects. The review also focuses both on methodological issues such as technical aspects of the stimulation ( electrodes position and dimension; current intensity; duration of protocol) and on the inclusion of appropriate assessment tools for cognition. A further aspect considered is the best timing to administer tDCS: before, during after cognitive rehabilitation. We conclude that more studies with shared methodology are needed to have a better understanding of the efficacy of tDCS as a new tool for rehabilitation of cognitive disorders in a range of neurological disordersopenCappon, D; Jahanshahi, M; Bisiacchi, PCappon, Davide; Jahanshahi, M; Bisiacchi, Patrizi

Naturalistic monitoring of the affect-heart rate relationship: A Day Reconstruction Study

Objective: Prospective studies have linked both negative affective states and trait neuroticism with hypertension, cardiovascular disease, and mortality. However, identifying how fluctuations in cardiovascular activity in day-to-day settings are related to changes in affect and stable personality characteristics has remained a methodological and logistical challenge. Design - In the present study, we tested the association between affect, affect variability, personality and heart rate (HR) in daily life. Measures: We utilized an online day reconstruction survey to produce a continuous account of affect, interaction, and activity patterns during waking hours. Ambulatory HR was assessed during the same period. Consumption, activity, and baseline physiological characteristics were assessed in order to isolate the relationships between affect, personality and heart rate. Results: Negative affect and variability in positive affect predicted an elevated ambulatory HR and tiredness a lower HR. Emotional stability was inversely related to HR, whereas agreeableness predicted a higher HR. Baseline resting HR was unrelated to either affect or personality. Conclusion: The results suggest that both state and trait factors implicated in negative affectivity may be risk factors for increased cardiovascular reactivity in everyday life. Combining day reconstruction with psychophysiological and environmental monitoring is discussed as a minimally invasive method with promising interdisciplinary relevance.heart rate, negative affect, affect variability, Big Five, Day Reconstruction Method

On the use of ultraviolet photography and ultraviolet wing patterns in butterfly morphology and taxonomy

In a series of feeding experiments we found that, depending on the larval food plant species or part of food plant ingested, individuals of the blue butterfly Polyommatus icarus (Lycaenidae) exhibit broad variation of wing patterns in the ultraviolet (UV) range of wavelengths which is invisible to humans. Such intraspecific variability in UV wing patterns has been underestimated thus far due to the rather demanding approach needed to study these patterns. We discuss methodological problems with the assessment of butterfly UV wing patterns by UV photography. Given proper standardization, UV photography is a suitable method to qualitatively assess UV wing patterns for possible use in morphology or systematics. Spectrophotometly should preferably be used as quantitative method when consideling UV wing patterns in a communication context. No higher value should be attached to UV wing patterns as compared to human visible wing patterns

Small-scale farming diversity and bioeconomic environment variability : a modelling approach. Sub theme : 1.2. Integration of micro-strategies with macro-economic factors

Modelling is seen by many scientists as a powerful tool to assess the interaction between variability in the bioeconomic environment of small-scale farmers and their resource management strategies. Two case studies on small-scale farming in Mexican and Brazilian savannas are presented. On one hand, the effect of climate variability on crop yields is highly dependent of the managing techniques used. On the other hand, the variability of prices, resulting in Mexico's case from the establishment of NAFTA and, in the Brazilian case, from the "-plano Real," dramatically increases the uncertainty of the economic results linked to technical choices. Modelling the real conditions of such farmer decisions requires integrating of both biophysical and economical knowledge. This work analyses the characteristics required for such models and ways to integrate them. It appears that the building and scaling up of the models should be driven by results of a study on farming system diversity