A new configurational bias scheme for sampling supramolecular structures.

This is the author accepted manuscript. The final version is available from the American Institute of Physics via http://dx.doi.org/10.1063/1.4904727We present a new simulation scheme which allows an efficient sampling of reconfigurable supramolecular structures made of polymeric constructs functionalized by reactive binding sites. The algorithm is based on the configurational bias scheme of Siepmann and Frenkel and is powered by the possibility of changing the topology of the supramolecular network by a non-local Monte Carlo algorithm. Such a plan is accomplished by a multi-scale modelling that merges coarse-grained simulations, describing the typical polymer conformations, with experimental results accounting for free energy terms involved in the reactions of the active sites. We test the new algorithm for a system of DNA coated colloids for which we compute the hybridisation free energy cost associated to the binding of tethered single stranded DNAs terminated by short sequences of complementary nucleotides. In order to demonstrate the versatility of our method, we also consider polymers functionalized by receptors that bind a surface decorated by ligands. In particular, we compute the density of states of adsorbed polymers as a function of the number of ligand-receptor complexes formed. Such a quantity can be used to study the conformational properties of adsorbed polymers useful when engineering adsorption with tailored properties. We successfully compare the results with the predictions of a mean field theory. We believe that the proposed method will be a useful tool to investigate supramolecular structures resulting from direct interactions between functionalized polymers for which efficient numerical methodologies of investigation are still lacking

Hydraulic flux–responsive hormone redistribution determines root branching

Plant roots exhibit plasticity in their branching patterns to forage efficiently for heterogeneously distributed resources, such as soil water. The xerobranching response represses lateral root formation when roots lose contact with water. Here, we show that xerobranching is regulated by radial movement of the phloem-derived hormone abscisic acid, which disrupts intercellular communication between inner and outer cell layers through plasmodesmata. Closure of these intercellular pores disrupts the inward movement of the hormone signal auxin, blocking lateral root branching. Once root tips regain contact with moisture, the abscisic acid response rapidly attenuates. Our study reveals how roots adapt their branching pattern to heterogeneous soil water conditions by linking changes in hydraulic flux with dynamic hormone redistribution

26th Annual Computational Neuroscience Meeting (CNS*2017): Part 3 - Meeting Abstracts - Antwerp, Belgium. 15–20 July 2017

This work was produced as part of the activities of FAPESP Research,\ud Disseminations and Innovation Center for Neuromathematics (grant\ud 2013/07699-0, S. Paulo Research Foundation). NLK is supported by a\ud FAPESP postdoctoral fellowship (grant 2016/03855-5). ACR is partially\ud supported by a CNPq fellowship (grant 306251/2014-0)

A Comparative Study of Ethylene Emanation upon Nitrogen Deficiency in Natural Accessions of Arabidopsis thaliana

Contains fulltext : 156865.pdf (publisher's version ) (Open Access

Oilseed Rape Cultivars Show Diversity of Root Morphologies with the Potential for Better Capture of Nitrogen

The worldwide demand for vegetable oils is rising. Oilseed rape (Brassica napus) diversifies cereal dominated crop rotations but requires important nitrogen input. Yet, the root organ is offering an untapped opportunity to improve the nitrogen capture in soil. This study evaluates three culture systems in controlled environment, to observe root morphology and to identify root attributes for superior biomass production and nitrogen use. The phenotypic diversity in a panel of 55 modern winter oilseed rape cultivars was screened in response to two divergent nitrate supplies. Upon in vitro and hydroponic cultures, a large variability for root morphologies was observed. Root biomass and morphological traits positively correlated with shoot biomass or leaf area. The activities of high-affinity nitrate transport systems correlated negatively with the leaf area, while the combined high- and low-affinity systems positively with the total root length. The X-ray computed tomography permitted to visualize the root system in pipes filled with soil. The in vitro root phenotype at germination stage was indicative of lateral root deployment in soil-grown plants. This study highlights great genetic potential in oilseed rape, which could be manipulated to optimize crop root characteristics and nitrogen capture with substantial implications for agricultural production

Oilseed Rape Cultivars Show Diversity of Root Morphologies with the Potential for Better Capture of Nitrogen

The worldwide demand for vegetable oils is rising. Oilseed rape (Brassica napus) diversifies cereal dominated crop rotations but requires important nitrogen input. Yet, the root organ is offering an untapped opportunity to improve the nitrogen capture in soil. This study evaluates three culture systems in controlled environment, to observe root morphology and to identify root attributes for superior biomass production and nitrogen use. The phenotypic diversity in a panel of 55 modern winter oilseed rape cultivars was screened in response to two divergent nitrate supplies. Upon in vitro and hydroponic cultures, a large variability for root morphologies was observed. Root biomass and morphological traits positively correlated with shoot biomass or leaf area. The activities of high-affinity nitrate transport systems correlated negatively with the leaf area, while the combined high- and low-affinity systems positively with the total root length. The X-ray computed tomography permitted to visualize the root system in pipes filled with soil. The in vitro root phenotype at germination stage was indicative of lateral root deployment in soil-grown plants. This study highlights great genetic potential in oilseed rape, which could be manipulated to optimize crop root characteristics and nitrogen capture with substantial implications for agricultural production

Menopausal symptoms in epithelial ovarian cancer survivors: a GINECO VIVROVAIRE2 study

Objective - We have previously shown that epithelial ovarian cancer (EOC) and its treatments have negative effects on long-term quality of life (QoL) and fatigue. The present multicenter study investigated the main menopausal symptoms and gynecological management of EOC survivors (EOCS). Methods - 166 patients with relapse-free ≥3 years after the end of treatment attended a consultation with a gynecologist, including a questionnaire related to vasomotor symptoms (VMS) and sexuality, a clinical examination, a blood sample and an osteodensitometry. QoL, fatigue, insomnia and mood disorders were measured with validated questionnaires and correlated to VMS. VMS and QoL were assessed according to natural menopause (NM) or surgical menopause (SM). Results - Mean age at the survey was 62 [21–83] years and stage III/IV (48%). Mean delay since the end of treatment was 6 years. Fifty-nine patients (36%) had SM. Half of patients reported VMS. Seventy-two percent of EOCS with SM had VMS compared to 41% with NM (P Conclusions - VMS and sexual disorders are frequently reported by EOCS, particularly among patients with SM. Most EOCS with menopausal symptoms could benefit from HRT to improve these symptoms

Long-term fatigue and quality of life among epithelial ovarian cancer survivors: a GINECO case/control VIVROVAIRE I study

International audienc