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Division IV organises astronomers studying the characterisation, interior and atmospheric structure, and evolution of stars of all masses, ages, and chemical compositions. The Executive Committee of the Division comprises the Presidents of the Five Commissions of the Division, and the Past Division President.
One of the main tasks of the Division is to advise the Executive Committee of the IAU on meetings proposed by members of the IAU. Members wishing to seek IAU support for proposed scientific meetings should follow the IAU rules for such meetings.
In order to highlight the genetic status and origin of Moroccan apricot populations, trees were collected from ten oasis agroecosystems and analysed with AFLP markers. A total of 87 accessions and 12 cultivars grown in Moroccan orchards, including ‘Canino’ and ‘Del Patriarca’ cultivars, were surveyed and compared with in situ Tunisian and ex situ Montfavet (France) collections. Our results highlighted a narrow genetic diversity in the Maghreb region (Tunisia and Morocco) associated with a strong differentiation from the other groups, which supports a bottleneck effect. A similar model was illustrated at a finer geographical scale, i.e. the Draa Valley in Morocco. Genetic structure appeared as two major clusters subdivided into six sub-clusters in which Moroccan germplasm constituted specific groups in comparison with other Mediterranean apricots. Moroccan germplasm was classified into three sub-clusters, two of which were formed by genotypes related to ‘Del Patriarca’ and ‘Canino’, respectively. The present study highlights the wide Moroccan apricot's diversity in traditional agroecosystems, and also suggests a substantial gene flow occurring from recently introduced cultivars (‘Canino’ and ‘Del Patriarca’) to local apricot populations, thus leading to local germplasm diversification through seedling propagation. If we consider its geographical position, the historical diffusion of the species and farming practices, Morocco could be viewed as an additional centre of secondary diversification for apricot. Understanding the origin and specificity of local apricot populations is crucial for managing local collections in regard to adaptive traits for arid and Saharan conditions as well as for introducing local genetic resources into current breeding programmes.
Catherine Esnouf, Institut National de la Recherche Agronomique (INRA), Paris,Marie Russel, Institut National de la Recherche Agronomique (INRA), Paris,Nicolas Bricas, Centre de Co-opération Internationale en Recherche Agronomique pour le Développement (CIRAD), Paris
Regional and global food systems are constantly evolving, thus the contextual elements presented in Chapter 1 are likely to evolve, and food systems will be transformed. Because it is impossible to predict the food systems of tomorrow, we have adopted a foresight approach in order to try and understand possible future changes. Our approach, which is presented in the first part of this chapter, has therefore mainly been based on identifying the main drivers of the transformation of food systems. This work was the fruit of collective discussions by a multidisciplinary group made up of some 15 experts. The plurality of their views and their areas of competence allowed them to analyse the potential impacts of the different evolutions identified relative to the sustainability of food systems in terms of their nutritional, economic, social, cultural, environmental and territorial dimensions. This step of the analysis also enabled us to highlight a certain number of points at issue, which are presented in the second part of the chapter; this does not end with a presentation of different scenarios (as might have been expected), but concludes with the three transversal messages arising from debate by this workshop: issues linked to inequalities of access to food, territorial dynamics and the governance of food systems.
Food systems evolving under the effects of various factors
Through the identification of factors underlying the transformation of food systems, it appears clearly that some trends have already been identified (see, in particular, Chapter 1 on the context and the challenges of food systems, and the retrospective analysis described in Chapter 2). Nevertheless, these trends involve a certain number of questions and uncertainties, notably regarding the nature and degree of their potential effects. These uncertainties thus open the way to contrasting scenarios for food systems throughout the world (see Figure 9.1).
Stereotactic radiosurgery (SRS) is known to safely result in a high obliteration rate for small and medium sized arteriovenous malformations (AVM).
To evaluate the long-term outcome of patients treated with SRS, with special emphasis given to obliteration and toxicity rates.
We performed a review of 43 cerebral AVM patients, treated from 1998 to 2008 with a single SRS dose ranging from 21-25 Gy. Of these, 37 had a minimal follow-up of one year. Medical files were reviewed to assess patient and AVM characteristics, the SRS treatment, therapy prior to SRS, the obliteration rate and toxicities. Whenever necessary, outcome data was supplemented by telephone interviews with the patient or treating physician.
AVM size was ≥3cm in diameter in 21% of patients. Five patients (11.6%) underwent surgery prior to SRS and 31 patients (72.1%) received one or more embolizations prior to SRS. Of the patients followed with angiography ≥1 year post-SRS, 89% (33/37) had a complete obliteration of the nidus, after a median time of 24.7 months post-treatment. Embolization prior to SRS was not predictive of outcome. One patient suffered a non-fatal haemorrhage between treatment and obliteration. The rate of symptomatic radiation-induced radiological changes was 8.1%.
Our study shows both obliteration and complication rates in the upper limit of those reported in the literature. SRS seems an attractive treatment option for small AVMs. Unlike other reports, the prior use of embolization did not impact negatively on obliteration rates.
To identify and describe factors associated with food shop (known as tuck shop in South Africa) and lunchbox behaviours of primary-school learners in South Africa.
Analysis of data collected in 2008 from a cross-sectional survey.
Sixteen primary schools in the Western Cape, South Africa.
A total of 717 grade 4 learners aged 10–12 years.
A 24 h recall established that 69 % of learners carried a lunchbox to school and 49 % had consumed at least one item purchased from the school food shop/vendor. Most lunchboxes contained white bread with processed meat, whereas the most frequent food shop/vendor purchase comprised chips/crisps. Learners who carried a lunchbox to school had significantly lower BMI percentiles (P = 0·002) and BMI-for-age (P = 0·034), compared with their counterparts. Moreover, they were younger, had higher standard-of-living and dietary diversity scores, consumed more meals per day, had greater self-efficacy and came from predominantly urban schools, compared with those who did not carry a lunchbox to school. Learners who ate food shop/vendor purchases had a lower standard-of-living score and higher dietary diversity and meal scores. Only 2 % of learners were underweight, whereas 19 % were stunted and 21 % were overweight/obese (BMI ≥ 25 kg/m2).
Children who carried a lunchbox to school appeared to have greater dietary diversity, consumed more regular meals, had a higher standard of living and greater nutritional self-efficacy compared with those who did not carry a lunchbox to school.
It has been a long standing problem in astrochemistry to explain how molecules can form in a highly dilute environment such as the interstellar medium. In the last decennium more and more evidence has been found that the observed mix of small and complex, stable and highly transient species in space is the cumulative result of gas phase and solid state reactions as well as gas-grain interactions. Solid state reactions on icy dust grains are specifically found to play an important role in the formation of the more complex “organic” compounds. In order to investigate the underlying physical and chemical processes detailed laboratory based experiments are needed that simulate surface reactions triggered by processes as different as thermal heating, photon (UV) irradiation and particle (atom, cosmic ray, electron) bombardment of interstellar ice analogues. Here, some of the latest research performed in the Sackler Laboratory for Astrophysics in Leiden, the Netherlands is reviewed. The focus is on hydrogenation, i.e., H-atom addition reactions and vacuum ultraviolet irradiation of interstellar ice analogues at astronomically relevant temperatures. It is shown that solid state processes are crucial in the chemical evolution of the interstellar medium, providing pathways towards molecular complexity in space.
Polycrystalline transparent Yb:Sc2O3 ceramics were obtained in the best conditions by a solid-state reaction route using high purity Sc2O3 and Yb2O3 powders with TEOS as a sintering aid. The as-prepared powders containing various ytterbium content were characterized by BET measurements, XRD and FEG-SEM. The sintering behaviour of the powders was investigated by dilatometry. The sintered materials microstructures were observed by FEG-SEM. EPMA allowed to characterize the repartition of the dopant Yb3+ in the Sc2O3 matrix.
We aimed to describe the vitamin D status of young women living in two Chinese cities in the spring – Beijing in the north (latitude 39° north) and Hong Kong (latitude 22° north) in the south. We also examined the relationship between serum 25-hydroxyvitamin D and parathyroid hormone (PTH) concentrations to determine a threshold for serum 25-hydroxyvitamin D above which there is no further suppression of PTH. Finally, we examined whether dietary Ca intake influences this relationship. Non-pregnant women aged 18–40 years (n 441) were recruited between February and June. Fasting blood was collected and dietary intakes were assessed using 5 d food records. Mean serum 25-hydroxyvitamin D concentration was lower in Beijing than Hong Kong women (29 v. 34 nmol/l; P < 0·001). Vitamin D deficiency ( ≤ 25 nmol/l) was indicated in 40 % of Beijing and 18 % of Hong Kong women, and over 90 % of women in both cities were insufficient ( ≤ 50 nmol/l). Mean Ca and vitamin D intakes were 478 mg/d and 2·0 μg/d, respectively. The relationship between 25-hydroxyvitamin D concentration and PTH was linear throughout the range with a slope of − 0·36 (different from 0; P < 0·001; R 0·26), with no apparent threshold. There was no influence of Ca intake on the relationship between 25-hydroxyvitamin D and PTH concentration. Vitamin D deficiency is common and insufficiency is very common in non-pregnant women in Hong Kong and Beijing during spring. Serum 25-hydroxyvitamin D was inversely associated with PTH with no apparent threshold. Strategies such as vitamin D fortification or supplementation may be required.
Background: It is generally accepted that Alzheimer's disease (AD) is mainly characterized by memory disorders. Although recent studies also point to an important role of attention deficits early in the disease, this notion has not yet emerged in clinical practice. Our aim was to assess whether attention, quantified by reaction times, can discriminate between patients with mild AD and controls and therefore contribute to clinical diagnosis.
Methods: In a cross-sectional study, 33 patients with mild AD were matched with cognitively healthy elderly controls for age, gender, educational level and depressive mood. Selective attention (SA), alternating attention (AA) and error-rates were measured by a modified reaction time test.
Results: Significant differences between both groups were found for all measures. Logistic regression showed that SA (corrected for individual processing speed) and error-rates could correctly classify subjects with an overall hit ratio of 81%. When attention measures were not corrected for individual processing speed, the overall hit ratio improved to 97%.
Conclusion: SA and AA deteriorate in patients with mild AD and these measures can be used to discriminate between patients and matched controls, independently of depressive mood.
The cause of the non-disjunction leading to trisomy 21 remains unclear. Recent evidence has suggested that 5, 10-methylenetetrahydrofolate reductase (MTHFR) and/or methionine synthase reductase (MTRR) might contribute to the maternal risk of trisomy 21. The purpose of the present study was to analyse these findings among the French population and to investigate whether common polymorphisms in genes of the folate and homocysteine pathway, including the MTHFR 677C>T, MTHFR 1298A>C, the methionine synthase (MTR) 2756A>G, the cystathionine β-synthase (CBS) 844Ins68 and the reduced folate carrier (RFC-1) 80G>A polymorphisms, contribute to the risk of trisomy 21. The risk was studied by analysing independent and combined genotypes in 119 case mothers and 119 control mothers. The MTHFR 677T, MTHFR 1298C, MTR2756G, MTRR66G, CBSIns68+ and the RFC-1 80G allele frequencies were not significantly different among French case mothers, compared with control mothers. The risk of having a child with trisomy 21 did not appear to be linked to polymorphisms in genes associated with folate and homocysteine metabolism.
Most adults with regular transposition (the combinations of concordant atrioventricular and discordant ventriculo-arterial connections) have undergone either the Mustard or Senning procedure in childhood. It is unclear whether adverse events differ according to the surgery performed. With this in mind, we conducted a systematic review and meta-analysis to compare long-term outcomes. We searched systematically entries to MEDLINE and EMBASE databases from January 1966 through August 2003, supplementing the search by secondary sources. Comparative studies were required to include at least 10 patients in each cohort of Mustard or Senning procedure, and to report overall survival. Data were extracted by two independent reviewers. We used a component approach to assess quality. On the basis of assessment of heterogeneity, we then used a random-effects model for pooled analyses. In all, we included seven studies, incorporating 885 patients. We found a trend towards lower mortality for the 369 patients undergoing a Mustard procedure when compared to 474 submitted to the Senning operation, with a hazard ratio of 0.63 and 95% confidence intervals between 0.35 and 1.14 (p = 0.13). This trend increased with the size of the sample (p = 0.004). Obstruction in the systemic venous pathway was more common in those having the Mustard procedure, with a risk ratio of 3.5 and 95% confidence intervals from 1.8 to 7.0 (p < 0.001), with a trend towards greater obstruction of the pulmonary venous pathway in those undergoing the Senning procedure, 7.6% vs. 3.8% (p = 0.27). A trend towards fewer residual shunts was observed for those with Mustard baffles, 7.0% vs. 14.1% (p = 0.10). Sinus nodal dysfunction, however, was more common after the Mustard procedure. Data regarding atrial tachydysrhythmias was inconclusive. Systemic cardiac failure and functional capacity, was similar. We conclude that outcomes are not uniform among patients submitted to the Mustard and Senning procedures. Knowledge of such differences may facilitate stratification of risk and follow-up.