Meridional circulation dynamics in a cyclic convective dynamo

Surface observations indicate that the speed of the solar meridional circulation in the photosphere varies in anti-phase with the solar cycle. The current explanation for the source of this variation is that inflows into active regions alter the global surface pattern of the meridional circulation. When these localized inflows are integrated over a full hemisphere, they contribute to slowing down the axisymmetric poleward horizontal component. The behavior of this large-scale flow deep inside the convection zone remains largely unknown. Present helioseismic techniques are not sensitive enough to capture the dynamics of this weak large-scale flow. Moreover, the large time of integration needed to map the meridional circulation inside the convection zone, also masks some of the possible dynamics on shorter timescales. In this work we examine the dynamics of the meridional circulation that emerges from a 3D MHD global simulation of the solar convection zone. Our aim is to assess and quantify the behavior of meridional circulation deep inside the convection zone where the cyclic large-scale magnetic field can reach considerable strength. Our analyses indicate that the meridional circulation morphology and amplitude are both highly influenced by the magnetic field via the impact of magnetic torques on the global angular momentum distribution. A dynamic feature induced by these magnetic torques is the development of a prominent upward flow at mid-latitudes in the lower convection zone that occurs near the equatorward edge of the toroidal bands and that peaks during cycle maximum. Globally, the dynamo-generated large-scale magnetic field drives variations in the meridional flow, in stark contrast to the conventional kinematic flux transport view of the magnetic field being advected passively by the flow.Centra-ISTGRPS-UdeMNatural Sciences and Engineering Research Council of CanadaNational Science FoundationUniversity of the Algarveinfo:eu-repo/semantics/publishedVersio

Buying Years to Extinction: Is Compensatory Mitigation for Marine Bycatch a Sufficient Conservation Measure for Long-Lived Seabirds?

Along the lines of the ‘polluter pays principle’, it has recently been proposed that the local long-line fishing industry should fund eradication of terrestrial predators at seabird breeding colonies, as a compensatory measure for the bycatch caused by the fishing activity. The measure is economically sound, but a quantitative and reliable test of its biological efficacy has never been conducted. Here, we investigated the demographic consequences of predator eradication for Cory's shearwater Calonectris diomedea, breeding in the Mediterranean, using a population model that integrates demographic rates estimated from individual life-history information with experimental measures of predation and habitat structure. We found that similar values of population growth rate can be obtained by different combinations of habitat characteristics, predator abundance and adult mortality, which explains the persistence of shearwater colonies in islands with introduced predators. Even so, given the empirically obtained values of survival, all combinations of predator abundance and habitat characteristics projected a decline in shearwater numbers. Perturbation analyses indicated that the value and the sensitivity of shearwater population growth rates were affected by all covariates considered and their interactions. A decrease in rat abundance delivered only a small increase in the population growth rate, whereas a change in adult survival (a parameter independent of rat abundance) had the strongest impact on population dynamics. When adult survival is low, rat eradication would allow us to “buy” years before extinction but does not reverse the process. Rat eradication can therefore be seen as an emergency measure if threats on adult survival are eliminated in the medium-term period. For species with low fecundity and long life expectancy, our results suggest that rat control campaigns are not a sufficient, self-standing measure to compensate the biological toll of long-line fisheries

Conditions for the Evolution of Gene Clusters in Bacterial Genomes

Genes encoding proteins in a common pathway are often found near each other along bacterial chromosomes. Several explanations have been proposed to account for the evolution of these structures. For instance, natural selection may directly favour gene clusters through a variety of mechanisms, such as increased efficiency of coregulation. An alternative and controversial hypothesis is the selfish operon model, which asserts that clustered arrangements of genes are more easily transferred to other species, thus improving the prospects for survival of the cluster. According to another hypothesis (the persistence model), genes that are in close proximity are less likely to be disrupted by deletions. Here we develop computational models to study the conditions under which gene clusters can evolve and persist. First, we examine the selfish operon model by re-implementing the simulation and running it under a wide range of conditions. Second, we introduce and study a Moran process in which there is natural selection for gene clustering and rearrangement occurs by genome inversion events. Finally, we develop and study a model that includes selection and inversion, which tracks the occurrence and fixation of rearrangements. Surprisingly, gene clusters fail to evolve under a wide range of conditions. Factors that promote the evolution of gene clusters include a low number of genes in the pathway, a high population size, and in the case of the selfish operon model, a high horizontal transfer rate. The computational analysis here has shown that the evolution of gene clusters can occur under both direct and indirect selection as long as certain conditions hold. Under these conditions the selfish operon model is still viable as an explanation for the evolution of gene clusters

Challenging the Moral Status of Blood Donation

The World Health Organisation encourages that blood donation becomes voluntary and unremunerated, a system already operated in the UK. Drawing on public documents and videos, this paper argues that blood donation is regarded and presented as altruistic and supererogatory. In advertisements, donation is presented as something undertaken for the benefit of others, a matter attracting considerable gratitude from recipients and the collecting organisation. It is argued that regarding blood donation as an act of supererogation is wrongheaded, and an alternative account of blood donation as moral obligation is presented. Two arguments are offered in support of this position. First, the principle of beneficence, understood in a broad consequentialist framework obliges donation where the benefit to the recipient is large and the cost to the donor relatively small. This argument can be applied, with differing levels of normativity, to various acts of donation. Second, the wrongness of free riding requires individuals to contribute to collective systems from which they benefit. Alone and in combination these arguments present moral reasons for donation, recognised in communication strategies elsewhere. Research is required to evaluate the potential effects on donation of a campaign which presents blood donation as moral obligation, but of wider importance is the recognition that other-regarding considerations in relation to our own as well as others’ health result in a range not only of choices but also of obligations

Roflumilast in moderate-to-severe chronic obstructive pulmonary disease treated with longacting bronchodilators: two randomised clinical trials

Background Patients with chronic obstructive pulmonary disease (COPD) have few options for treatment. The efficacy and safety of the phosphodiesterase-4 inhibitor roflumilast have been investigated in studies of patients with moderate-to-severe COPD, but not in those concomitantly treated with longacting inhaled bronchodilators. The effect of roflumilast on lung function in patients with COPD that is moderate to severe who are already being treated with salmeterol or tiotropium was investigated. Methods In two double-blind, multicentre studies done in an outpatient setting, after a 4-week run-in, patients older than 40 years with moderate-to-severe COPD were randomly assigned to oral roflumilast 500 mu g or placebo once a day for 24 weeks, in addition to salmeterol (M2-127 study) or tiotropium (M2-128 study). The primary endpoint was change in prebronchodilator forced expiratory volume in 1s (FEV(1)). Analysis was by intention to treat. The studies are registered with ClinicalTrials.gov, number NCT00313209 for M2-127, and NCT00424268 for M2-128. Findings In the salmeterol plus roflumilast trial, 466 patients were assigned to and treated with roflumilast and 467 with placebo; in the tiotropium plus roflumilast trial, 371 patients were assigned to and treated with roflumilast and 372 with placebo. Compared with placebo, roflumilast consistently improved mean prebronchodilator FEV(1) by 49 mL (p<0.0001) in patients treated with salmeterol, and 80 mL (p<0.0001) in those treated with tiotropium. Similar improvement in postbronchodilator FEV(1) was noted in both groups. Furthermore, roflumilast had beneficial effects on other lung function measurements and on selected patient-reported outcomes in both groups. Nausea, diarrhoea, weight loss, and, to a lesser extent, headache were more frequent in patients in the roflumilast groups. These adverse events were associated with increased patient withdrawal. Interpretation Roflumilast improves lung function in patients with COPD treated with salmeterol or tiotropium, and could become an important treatment for these patients

Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

Variation in Structure and Process of Care in Traumatic Brain Injury: Provider Profiles of European Neurotrauma Centers Participating in the CENTER-TBI Study.

INTRODUCTION: The strength of evidence underpinning care and treatment recommendations in traumatic brain injury (TBI) is low. Comparative effectiveness research (CER) has been proposed as a framework to provide evidence for optimal care for TBI patients. The first step in CER is to map the existing variation. The aim of current study is to quantify variation in general structural and process characteristics among centers participating in the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study. METHODS: We designed a set of 11 provider profiling questionnaires with 321 questions about various aspects of TBI care, chosen based on literature and expert opinion. After pilot testing, questionnaires were disseminated to 71 centers from 20 countries participating in the CENTER-TBI study. Reliability of questionnaires was estimated by calculating a concordance rate among 5% duplicate questions. RESULTS: All 71 centers completed the questionnaires. Median concordance rate among duplicate questions was 0.85. The majority of centers were academic hospitals (n = 65, 92%), designated as a level I trauma center (n = 48, 68%) and situated in an urban location (n = 70, 99%). The availability of facilities for neuro-trauma care varied across centers; e.g. 40 (57%) had a dedicated neuro-intensive care unit (ICU), 36 (51%) had an in-hospital rehabilitation unit and the organization of the ICU was closed in 64% (n = 45) of the centers. In addition, we found wide variation in processes of care, such as the ICU admission policy and intracranial pressure monitoring policy among centers. CONCLUSION: Even among high-volume, specialized neurotrauma centers there is substantial variation in structures and processes of TBI care. This variation provides an opportunity to study effectiveness of specific aspects of TBI care and to identify best practices with CER approaches

Epidemiology of intra-abdominal infection and sepsis in critically ill patients: “AbSeS”, a multinational observational cohort study and ESICM Trials Group Project

Purpose: To describe the epidemiology of intra-abdominal infection in an international cohort of ICU patients according to a new system that classifies cases according to setting of infection acquisition (community-acquired, early onset hospital-acquired, and late-onset hospital-acquired), anatomical disruption (absent or present with localized or diffuse peritonitis), and severity of disease expression (infection, sepsis, and septic shock). Methods: We performed a multicenter (n = 309), observational, epidemiological study including adult ICU patients diagnosed with intra-abdominal infection. Risk factors for mortality were assessed by logistic regression analysis. Results: The cohort included 2621 patients. Setting of infection acquisition was community-acquired in 31.6%, early onset hospital-acquired in 25%, and late-onset hospital-acquired in 43.4% of patients. Overall prevalence of antimicrobial resistance was 26.3% and difficult-to-treat resistant Gram-negative bacteria 4.3%, with great variation according to geographic region. No difference in prevalence of antimicrobial resistance was observed according to setting of infection acquisition. Overall mortality was 29.1%. Independent risk factors for mortality included late-onset hospital-acquired infection, diffuse peritonitis, sepsis, septic shock, older age, malnutrition, liver failure, congestive heart failure, antimicrobial resistance (either methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, extended-spectrum beta-lactamase-producing Gram-negative bacteria, or carbapenem-resistant Gram-negative bacteria) and source control failure evidenced by either the need for surgical revision or persistent inflammation. Conclusion: This multinational, heterogeneous cohort of ICU patients with intra-abdominal infection revealed that setting of infection acquisition, anatomical disruption, and severity of disease expression are disease-specific phenotypic characteristics associated with outcome, irrespective of the type of infection. Antimicrobial resistance is equally common in community-acquired as in hospital-acquired infection

The bHLH transcription factor SPATULA enables cytokinin signaling, and both activate auxin biosynthesis and transport genes at the medial domain of the gynoecium

[EN] Fruits and seeds are the major food source on earth. Both derive from the gynoecium and, therefore, it is crucial to understand the mechanisms that guide the development of this organ of angiosperm species. In Arabidopsis, the gynoecium is composed of two congenitally fused carpels, where two domains: medial and lateral, can be distinguished. The medial domain includes the carpel margin meristem (CMM) that is key for the production of the internal tissues involved in fertilization, such as septum, ovules, and transmitting tract. Interestingly, the medial domain shows a high cytokinin signaling output, in contrast to the lateral domain, where it is hardly detected. While it is known that cytokinin provides meristematic properties, understanding on the mechanisms that underlie the cytokinin signaling pattern in the young gynoecium is lacking. Moreover, in other tissues, the cytokinin pathway is often connected to the auxin pathway, but we also lack knowledge about these connections in the young gynoecium. Our results reveal that cytokinin signaling, that can provide meristematic properties required for CMM activity and growth, is enabled by the transcription factor SPATULA (SPT) in the medial domain. Meanwhile, cytokinin signaling is confined to the medial domain by the cytokinin response repressor ARABIDOPSIS HISTIDINE PHOSPHOTRANSFERASE 6 (AHP6), and perhaps by ARR16 (a type-A ARR) as well, both present in the lateral domains (presumptive valves) of the developing gynoecia. Moreover, SPT and cytokinin, probably together, promote the expression of the auxin biosynthetic gene TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS 1 (TAA1) and the gene encoding the auxin efflux transporter PIN-FORMED 3 (PIN3), likely creating auxin drainage important for gynoecium growth. This study provides novel insights in the spatiotemporal determination of the cytokinin signaling pattern and its connection to the auxin pathway in the young gynoecium.IRO, VMZM, HHU and PLS were supported by the Mexican National Council of Science and Technology (CONACyT) with a PhD fellowship (210085, 210100, 243380 and 219883, respectively). Work in the SDF laboratory was financed by the CONACyT grants CB-2012-177739, FC-2015-2/1061, and INFR-2015-253504, and NMM by the CONACyT grant CB-2011-165986. SDF, CF and LC acknowledge the support of the European Union FP7-PEOPLE-2009-IRSES project EVOCODE (grant no. 247587) and H2020-MSCARISE-2015 project ExpoSEED (grant no. 691109). SDF also acknowledges the Marine Biological Laboratory (MBL) in Woods Hole for a scholarship for the Gene Regulatory Networks for Development Course 2015 (GERN2015). IE acknowledges the International European Fellowship-METMADS project and the Universita degli Studi di Milano (RTD-A; 2016). Research in the laboratory of MFY was funded by NSF (grant IOS-1121055), NIH (grant 1R01GM112976-01A1) and the Paul D. Saltman Endowed Chair in Science Education (MFY). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Reyes Olalde, J.; Zuñiga, V.; Serwatowska, J.; Chávez Montes, R.; Lozano-Sotomayor, P.; Herrera-Ubaldo, H.; Gonzalez Aguilera, K.... (2017). The bHLH transcription factor SPATULA enables cytokinin signaling, and both activate auxin biosynthesis and transport genes at the medial domain of the gynoecium. PLoS Genetics. 13(4):1-31. https://doi.org/10.1371/journal.pgen.1006726S131134Reyes-Olalde, J. I., Zuñiga-Mayo, V. M., Chávez Montes, R. A., Marsch-Martínez, N., & de Folter, S. (2013). Inside the gynoecium: at the carpel margin. Trends in Plant Science, 18(11), 644-655. doi:10.1016/j.tplants.2013.08.002Alvarez-Buylla, E. R., Benítez, M., Corvera-Poiré, A., Chaos Cador, Á., de Folter, S., Gamboa de Buen, A., … Sánchez-Corrales, Y. E. (2010). Flower Development. The Arabidopsis Book, 8, e0127. doi:10.1199/tab.0127Bowman, J. L., Baum, S. F., Eshed, Y., Putterill, J., & Alvarez, J. (1999). 4 Molecular Genetics of Gynoecium Development in Arabidopsis. Current Topics in Developmental Biology Volume 45, 155-205. doi:10.1016/s0070-2153(08)60316-6Chávez Montes, R. A., Herrera-Ubaldo, H., Serwatowska, J., & de Folter, S. (2015). Towards a comprehensive and dynamic gynoecium gene regulatory network. Current Plant Biology, 3-4, 3-12. doi:10.1016/j.cpb.2015.08.002Marsch-Martínez, N., & de Folter, S. (2016). Hormonal control of the development of the gynoecium. Current Opinion in Plant Biology, 29, 104-114. doi:10.1016/j.pbi.2015.12.006Marsch-Martínez, N., Ramos-Cruz, D., Irepan Reyes-Olalde, J., Lozano-Sotomayor, P., Zúñiga-Mayo, V. M., & de Folter, S. (2012). The role of cytokinin during Arabidopsis gynoecia and fruit morphogenesis and patterning. The Plant Journal, 72(2), 222-234. doi:10.1111/j.1365-313x.2012.05062.xZhao, Z., Andersen, S. U., Ljung, K., Dolezal, K., Miotk, A., Schultheiss, S. J., & Lohmann, J. U. (2010). Hormonal control of the shoot stem-cell niche. Nature, 465(7301), 1089-1092. doi:10.1038/nature09126Ashikari, M. (2005). Cytokinin Oxidase Regulates Rice Grain Production. Science, 309(5735), 741-745. doi:10.1126/science.1113373Bartrina, I., Otto, E., Strnad, M., Werner, T., & Schmülling, T. (2011). Cytokinin Regulates the Activity of Reproductive Meristems, Flower Organ Size, Ovule Formation, and Thus Seed Yield in Arabidopsis thaliana. The Plant Cell, 23(1), 69-80. doi:10.1105/tpc.110.079079Hwang, I., Sheen, J., & Müller, B. (2012). Cytokinin Signaling Networks. Annual Review of Plant Biology, 63(1), 353-380. doi:10.1146/annurev-arplant-042811-105503Schaller, G. E., Bishopp, A., & Kieber, J. J. (2015). The Yin-Yang of Hormones: Cytokinin and Auxin Interactions in Plant Development. The Plant Cell, 27(1), 44-63. doi:10.1105/tpc.114.133595Kieber, J. J., & Schaller, G. E. (2010). The Perception of Cytokinin: A Story 50 Years in the Making: Figure 1. Plant Physiology, 154(2), 487-492. doi:10.1104/pp.110.161596Long, J. A., Moan, E. I., Medford, J. I., & Barton, M. K. (1996). A member of the KNOTTED class of homeodomain proteins encoded by the STM gene of Arabidopsis. Nature, 379(6560), 66-69. doi:10.1038/379066a0Jasinski, S., Piazza, P., Craft, J., Hay, A., Woolley, L., Rieu, I., … Tsiantis, M. (2005). KNOX Action in Arabidopsis Is Mediated by Coordinate Regulation of Cytokinin and Gibberellin Activities. Current Biology, 15(17), 1560-1565. doi:10.1016/j.cub.2005.07.023Yanai, O., Shani, E., Dolezal, K., Tarkowski, P., Sablowski, R., Sandberg, G., … Ori, N. (2005). Arabidopsis KNOXI Proteins Activate Cytokinin Biosynthesis. Current Biology, 15(17), 1566-1571. doi:10.1016/j.cub.2005.07.060Scofield, S., Dewitte, W., Nieuwland, J., & Murray, J. A. H. (2013). The Arabidopsis homeobox gene SHOOT MERISTEMLESS has cellular and meristem-organisational roles with differential requirements for cytokinin and CYCD3 activity. The Plant Journal, 75(1), 53-66. doi:10.1111/tpj.12198Gordon, S. P., Chickarmane, V. S., Ohno, C., & Meyerowitz, E. M. (2009). Multiple feedback loops through cytokinin signaling control stem cell number within the Arabidopsis shoot meristem. Proceedings of the National Academy of Sciences, 106(38), 16529-16534. doi:10.1073/pnas.0908122106Chickarmane, V. S., Gordon, S. P., Tarr, P. T., Heisler, M. G., & Meyerowitz, E. M. (2012). Cytokinin signaling as a positional cue for patterning the apical-basal axis of the growing Arabidopsis shoot meristem. Proceedings of the National Academy of Sciences, 109(10), 4002-4007. doi:10.1073/pnas.1200636109Leibfried, A., To, J. P. C., Busch, W., Stehling, S., Kehle, A., Demar, M., … Lohmann, J. U. (2005). WUSCHEL controls meristem function by direct regulation of cytokinin-inducible response regulators. Nature, 438(7071), 1172-1175. doi:10.1038/nature04270Werner, T., Motyka, V., Laucou, V., Smets, R., Van Onckelen, H., & Schmülling, T. (2003). Cytokinin-Deficient Transgenic Arabidopsis Plants Show Multiple Developmental Alterations Indicating Opposite Functions of Cytokinins in the Regulation of Shoot and Root Meristem Activity. The Plant Cell, 15(11), 2532-2550. doi:10.1105/tpc.014928Larsson, E., Franks, R. G., & Sundberg, E. (2013). Auxin and the Arabidopsis thaliana gynoecium. Journal of Experimental Botany, 64(9), 2619-2627. doi:10.1093/jxb/ert099Weijers, D., & Wagner, D. (2016). Transcriptional Responses to the Auxin Hormone. Annual Review of Plant Biology, 67(1), 539-574. doi:10.1146/annurev-arplant-043015-112122Robert, H. S., Crhak Khaitova, L., Mroue, S., & Benková, E. (2015). The importance of localized auxin production for morphogenesis of reproductive organs and embryos inArabidopsis. Journal of Experimental Botany, 66(16), 5029-5042. doi:10.1093/jxb/erv256Kuusk, S., Sohlberg, J. J., Magnus Eklund, D., & Sundberg, E. (2006). Functionally redundantSHIfamily genes regulate Arabidopsis gynoecium development in a dose-dependent manner. The Plant Journal, 47(1), 99-111. doi:10.1111/j.1365-313x.2006.02774.xSohlberg, J. J., Myrenås, M., Kuusk, S., Lagercrantz, U., Kowalczyk, M., Sandberg, G., & Sundberg, E. (2006). STY1regulates auxin homeostasis and affects apical-basal patterning of the Arabidopsis gynoecium. The Plant Journal, 47(1), 112-123. doi:10.1111/j.1365-313x.2006.02775.xStåldal, V., Sohlberg, J. J., Eklund, D. M., Ljung, K., & Sundberg, E. (2008). Auxin can act independently ofCRC,LUG,SEU,SPTandSTY1in style development but not apical-basal patterning of theArabidopsisgynoecium. New Phytologist, 180(4), 798-808. doi:10.1111/j.1469-8137.2008.02625.xVan Gelderen, K., van Rongen, M., Liu, A., Otten, A., & Offringa, R. (2016). An INDEHISCENT-Controlled Auxin Response Specifies the Separation Layer in Early Arabidopsis Fruit. Molecular Plant, 9(6), 857-869. doi:10.1016/j.molp.2016.03.005José Ripoll, J., Bailey, L. J., Mai, Q.-A., Wu, S. L., Hon, C. T., Chapman, E. J., … Yanofsky, M. F. (2015). microRNA regulation of fruit growth. Nature Plants, 1(4). doi:10.1038/nplants.2015.36Larsson, E., Roberts, C. J., Claes, A. R., Franks, R. G., & Sundberg, E. (2014). Polar Auxin Transport Is Essential for Medial versus Lateral Tissue Specification and Vascular-Mediated Valve Outgrowth in Arabidopsis Gynoecia. Plant Physiology, 166(4), 1998-2012. doi:10.1104/pp.114.245951Nole-Wilson, S., Azhakanandam, S., & Franks, R. G. (2010). Polar auxin transport together with AINTEGUMENTA and REVOLUTA coordinate early Arabidopsis gynoecium development. Developmental Biology, 346(2), 181-195. doi:10.1016/j.ydbio.2010.07.016De Folter, S. (2016). Auxin Is Required for Valve Margin Patterning in Arabidopsis After All. Molecular Plant, 9(6), 768-770. doi:10.1016/j.molp.2016.05.005Moubayidin, L., & Østergaard, L. (2014). Dynamic Control of Auxin Distribution Imposes a Bilateral-to-Radial Symmetry Switch during Gynoecium Development. Current Biology, 24(22), 2743-2748. doi:10.1016/j.cub.2014.09.080Girin, T., Paicu, T., Stephenson, P., Fuentes, S., Körner, E., O’Brien, M., … Østergaard, L. (2011). INDEHISCENT and SPATULA Interact to Specify Carpel and Valve Margin Tissue and Thus Promote Seed Dispersal in Arabidopsis. The Plant Cell, 23(10), 3641-3653. doi:10.1105/tpc.111.090944Ioio, R. D., Nakamura, K., Moubayidin, L., Perilli, S., Taniguchi, M., Morita, M. T., … Sabatini, S. (2008). A Genetic Framework for the Control of Cell Division and Differentiation in the Root Meristem. Science, 322(5906), 1380-1384. doi:10.1126/science.1164147Bishopp, A., Help, H., El-Showk, S., Weijers, D., Scheres, B., Friml, J., … Helariutta, Y. (2011). A Mutually Inhibitory Interaction between Auxin and Cytokinin Specifies Vascular Pattern in Roots. Current Biology, 21(11), 917-926. doi:10.1016/j.cub.2011.04.017De Rybel, B., Adibi, M., Breda, A. S., Wendrich, J. R., Smit, M. E., Novák, O., … Weijers, D. (2014). Integration of growth and patterning during vascular tissue formation in Arabidopsis. Science, 345(6197), 1255215. doi:10.1126/science.1255215Pernisova, M., Klima, P., Horak, J., Valkova, M., Malbeck, J., Soucek, P., … Hejatko, J. (2009). Cytokinins modulate auxin-induced organogenesis in plants via regulation of the auxin efflux. Proceedings of the National Academy of Sciences, 106(9), 3609-3614. doi:10.1073/pnas.0811539106Cheng, Z. J., Wang, L., Sun, W., Zhang, Y., Zhou, C., Su, Y. H., … Zhang, X. S. (2012). Pattern of Auxin and Cytokinin Responses for Shoot Meristem Induction Results from the Regulation of Cytokinin Biosynthesis by AUXIN RESPONSE FACTOR3. Plant Physiology, 161(1), 240-251. doi:10.1104/pp.112.203166Alvarez, J., & Smyth, D. R. (2002). CRABS CLAWandSPATULAGenes Regulate Growth and Pattern Formation during Gynoecium Development inArabidopsis thaliana. International Journal of Plant Sciences, 163(1), 17-41. doi:10.1086/324178Groszmann, M., Bylstra, Y., Lampugnani, E. R., & Smyth, D. R. (2010). Regulation of tissue-specific expression of SPATULA, a bHLH gene involved in carpel development, seedling germination, and lateral organ growth in Arabidopsis. Journal of Experimental Botany, 61(5), 1495-1508. doi:10.1093/jxb/erq015Smyth, D. R., Bowman, J. L., & Meyerowitz, E. M. (1990). Early flower development in Arabidopsis. The Plant Cell, 2(8), 755-767. doi:10.1105/tpc.2.8.755Müller, B., & Sheen, J. (2008). Cytokinin and auxin interaction in root stem-cell specification during early embryogenesis. Nature, 453(7198), 1094-1097. doi:10.1038/nature06943Argyros, R. D., Mathews, D. E., Chiang, Y.-H., Palmer, C. M., Thibault, D. M., Etheridge, N., … Schaller, G. E. (2008). Type B Response Regulators of Arabidopsis Play Key Roles in Cytokinin Signaling and Plant Development. The Plant Cell, 20(8), 2102-2116. doi:10.1105/tpc.108.059584Mason, M. G., Mathews, D. E., Argyros, D. A., Maxwell, B. B., Kieber, J. J., Alonso, J. M., … Schaller, G. E. (2005). Multiple Type-B Response Regulators Mediate Cytokinin Signal Transduction in Arabidopsis. The Plant Cell, 17(11), 3007-3018. doi:10.1105/tpc.105.035451Ishida, K., Yamashino, T., Yokoyama, A., & Mizuno, T. (2008). Three Type-B Response Regulators, ARR1, ARR10 and ARR12, Play Essential but Redundant Roles in Cytokinin Signal Transduction Throughout the Life Cycle of Arabidopsis thaliana. Plant and Cell Physiology, 49(1), 47-57. doi:10.1093/pcp/pcm165Yokoyama, A., Yamashino, T., Amano, Y.-I., Tajima, Y., Imamura, A., Sakakibara, H., & Mizuno, T. (2006). Type-B ARR Transcription Factors, ARR10 and ARR12, are Implicated in Cytokinin-Mediated Regulation of Protoxylem Differentiation in Roots of Arabidopsis thaliana. Plant and Cell Physiology, 48(1), 84-96. doi:10.1093/pcp/pcl040Schuster, C., Gaillochet, C., & Lohmann, J. U. (2015). Arabidopsis HECATE genes function in phytohormone control during gynoecium development. Development, 142(19), 3343-3350. doi:10.1242/dev.120444Toledo-Ortiz, G., Huq, E., & Quail, P. H. (2003). The Arabidopsis Basic/Helix-Loop-Helix Transcription Factor Family. The Plant Cell, 15(8), 1749-1770. doi:10.1105/tpc.013839Reymond, M. C., Brunoud, G., Chauvet, A., Martínez-Garcia, J. F., Martin-Magniette, M.-L., Monéger, F., & Scutt, C. P. (2012). A Light-Regulated Genetic Module Was Recruited to Carpel Development in Arabidopsis following a Structural Change to SPATULA. The Plant Cell, 24(7), 2812-2825. doi:10.1105/tpc.112.097915Ballester, P., Navarrete-Gómez, M., Carbonero, P., Oñate-Sánchez, L., & Ferrándiz, C. (2015). Leaf expansion in Arabidopsis is controlled by a TCP-NGA regulatory module likely conserved in distantly related species. Physiologia Plantarum, 155(1), 21-32. doi:10.1111/ppl.12327Hellens, R., Allan, A., Friel, E., Bolitho, K., Grafton, K., Templeton, M., … Laing, W. (2005). Plant Methods, 1(1), 13. doi:10.1186/1746-4811-1-13Makkena, S., & Lamb, R. S. (2013). The bHLH transcription factor SPATULA regulates root growth by controlling the size of the root meristem. BMC Plant Biology, 13(1), 1. doi:10.1186/1471-2229-13-1Stepanova, A. N., Robertson-Hoyt, J., Yun, J., Benavente, L. M., Xie, D.-Y., Doležal, K., … Alonso, J. M. (2008). TAA1-Mediated Auxin Biosynthesis Is Essential for Hormone Crosstalk and Plant Development. Cell, 133(1), 177-191. doi:10.1016/j.cell.2008.01.047Bhargava, A., Clabaugh, I., To, J. P., Maxwell, B. B., Chiang, Y.-H., Schaller, G. E., … Kieber, J. J. (2013). Identification of Cytokinin-Responsive Genes Using Microarray Meta-Analysis and RNA-Seq in Arabidopsis. Plant Physiology, 162(1), 272-294. doi:10.1104/pp.113.217026Sakai, H., Aoyama, T., & Oka, A. (2000). Arabidopsis ARR1 and ARR2 response regulators operate as transcriptional activators. The Plant Journal, 24(6), 703-711. doi:10.1046/j.1365-313x.2000.00909.xSakai, H. (2001). ARR1, a Transcription Factor for Genes Immediately Responsive to Cytokinins. Science, 294(5546), 1519-1521. doi:10.1126/science.1065201Moubayidin, L., Di Mambro, R., Sozzani, R., Pacifici, E., Salvi, E., Terpstra, I., … Sabatini, S. (2013). Spatial Coordination between Stem Cell Activity and Cell Differentiation in the Root Meristem. Developmental Cell, 26(4), 405-415. doi:10.1016/j.devcel.2013.06.025Benková, E., Michniewicz, M., Sauer, M., Teichmann, T., Seifertová, D., Jürgens, G., & Friml, J. (2003). Local, Efflux-Dependent Auxin Gradients as a Common Module for Plant Organ Formation. Cell, 115(5), 591-602. doi:10.1016/s0092-8674(03)00924-3Okada, K., Ueda, J., Komaki, M. K., Bell, C. J., & Shimura, Y. (1991). Requirement of the Auxin Polar Transport System in Early Stages of Arabidopsis Floral Bud Formation. The Plant Cell, 677-684. doi:10.1105/tpc.3.7.677Blilou, I., Xu, J., Wildwater, M., Willemsen, V., Paponov, I., Friml, J., … Scheres, B. (2005). The PIN auxin efflux facilitator network controls growth and patterning in Arabidopsis roots. Nature, 433(7021), 39-44. doi:10.1038/nature03184Mahonen, A. P. (2006). Cytokinin Signaling and Its Inhibitor AHP6 Regulate Cell Fate During Vascular Development. Science, 311(5757), 94-98. doi:10.1126/science.1118875Besnard, F., Refahi, Y., Morin, V., Marteaux, B., Brunoud, G., Chambrier, P., … Vernoux, T. (2013). Cytokinin signalling inhibitory fields provide robustness to phyllotaxis. Nature, 505(7483), 417-421. doi:10.1038/nature12791Longabaugh, W. J. R., Davidson, E. H., & Bolouri, H. (2005). Computational representation of developmental genetic regulatory networks. Developmental Biology, 283(1), 1-16. doi:10.1016/j.ydbio.2005.04.023Faure, E., Peter, I. S., & Davidson, E. H. (2013). A New Software Package for Predictive Gene Regulatory Network Modeling and Redesign. Journal of Computational Biology, 20(6), 419-423. doi:10.1089/cmb.2012.0297Mangan, S., & Alon, U. (2003). Structure and function of the feed-forward loop network motif. Proceedings of the National Academy of Sciences, 100(21), 11980-11985. doi:10.1073/pnas.2133841100Chen, Q., Liu, Y., Maere, S., Lee, E., Van Isterdael, G., Xie, Z., … Vanneste, S. (2015). A coherent transcriptional feed-forward motif model for mediating auxin-sensitive PIN3 expression during lateral root development. Nature Communications, 6(1). doi:10.1038/ncomms9821Qiu, K., Li, Z., Yang, Z., Chen, J., Wu, S., Zhu, X., … Zhou, X. (2015). EIN3 and ORE1 Accelerate Degreening during Ethylene-Mediated Leaf Senescence by Directly Activating Chlorophyll Catabolic Genes in Arabidopsis. PLOS Genetics, 11(7), e1005399. doi:10.1371/journal.pgen.1005399Seaton, D. D., Smith, R. W., Song, Y. H., MacGregor, D. R., Stewart, K., Steel, G., … Halliday, K. J. (2015). Linked circadian outputs control elongation growth and flowering in response to photoperiod and temperature. Molecular Systems Biology, 11(1), 776. doi:10.15252/msb.20145766Roeder, A. H. K., & Yanofsky, M. F. (2006). Fruit Development in Arabidopsis. The Arabidopsis Book, 4, e0075. doi:10.1199/tab.0075Marsch-Martínez, N., Reyes-Olalde, J. I., Ramos-Cruz, D., Lozano-Sotomayor, P., Zúñiga-Mayo, V. M., & de Folter, S. (2012). Hormones talking. Plant Signaling & Behavior, 7(12), 1698-1701. doi:10.4161/psb.22422Balanza, V., Navarrete, M., Trigueros, M., & Ferrandiz, C. (2006). Patterning the female side of Arabidopsis: the importance of hormones. Journal of Experimental Botany, 57(13), 3457-3469. doi:10.1093/jxb/erl188Kamiuchi, Y., Yamamoto, K., Furutani, M., Tasaka, M., & Aida, M. (2014). The CUC1 and CUC2 genes promote carpel margin meristem formation during Arabidopsis gynoecium development. Frontiers in Plant Science, 5. doi:10.3389/fpls.2014.00165Scofield, S., Dewitte, W., & Murray, J. A. H. (2007). The KNOX gene SHOOT MERISTEMLESS is required for the development of reproductive meristematic tissues in Arabidopsis. The Plant Journal, 50(5), 767-781. doi:10.1111/j.1365-313x.2007.03095.xLi, K., Yu, R., Fan, L.-M., Wei, N., Chen, H., & Deng, X. W. (2016). DELLA-mediated PIF degradation contributes to coordination of light and gibberellin signalling in Arabidopsis. Nature Communications, 7(1). doi:10.1038/ncomms11868Oh, E., Zhu, J.-Y., & Wang, Z.-Y. (2012). Interaction between BZR1 and PIF4 integrates brassinosteroid and environmental responses. Nature Cell Biology, 14(8), 802-809. doi:10.1038/ncb2545Sharma, N., Xin, R., Kim, D.-H., Sung, S., Lange, T., & Huq, E. (2016). NO FLOWERING IN SHORT DAY (NFL) is a bHLH transcription factor that promotes flowering specifically under short-day conditions inArabidopsis. Development, 143(4), 682-690. doi:10.1242/dev.128595Varaud, E., Brioudes, F., Szécsi, J., Leroux, J., Brown, S., Perrot-Rechenmann, C., & Bendahmane, M. (2011). AUXIN RESPONSE FACTOR8 Regulates Arabidopsis Petal Growth by Interacting with the bHLH Transcription Factor BIGPETALp. The Plant Cell, 23(3), 973-983. doi:10.1105/tpc.110.081653Savaldi-Goldstein, S., & Chory, J. (2008). Growth coordination and the shoot epidermis. Current Opinion in Plant Biology, 11(1), 42-48. doi:10.1016/j.pbi.2007.10.009Schuster, C., Gaillochet, C., Medzihradszky, A., Busch, W., Daum, G., Krebs, M., … Lohmann, J. U. (2014). A Regulatory Framework for Shoot Stem Cell Co