Radiation Hardness Studies in a CCD with High-Speed Column Parallel Readout

Charge Coupled Devices (CCDs) have been successfully used in several high energy physics experiments over the past two decades. Their high spatial resolution and thin sensitive layers make them an excellent tool for studying short-lived particles. The Linear Collider Flavour Identification (LCFI) collaboration is developing Column-Parallel CCDs (CPCCDs) for the vertex detector of the International Linear Collider (ILC). The CPCCDs can be read out many times faster than standard CCDs, significantly increasing their operating speed. The results of detailed simulations of the charge transfer inefficiency (CTI) of a prototype CPCCD are reported and studies of the influence of gate voltage on the CTI described. The effects of bulk radiation damage on the CTI of a CPCCD are studied by simulating the effects of two electron trap levels, 0.17 and 0.44 eV, at different concentrations and operating temperatures. The dependence of the CTI on different occupancy levels (percentage of hit pixels) and readout frequencies is also studied. The optimal operating temperature for the CPCCD, where the effects of the charge trapping are at a minimum, is found to be about 230 K for the range of readout speeds proposed for the ILC. The results of the full simulation have been compared with a simple analytic model.Comment: 3 pages, 6 figures; presented at IEEE'07, ALCPG'07, ICATPP'0

Microtubule-based perception of mechanical conflicts controls plant organ morphogenesis.

Precise coordination between cells and tissues is essential for differential growth in plants. During lateral root formation in Arabidopsis thaliana, the endodermis is actively remodeled to allow outgrowth of the new organ. Here, we show that microtubule arrays facing lateral root founder cells display a higher order compared to arrays on the opposite side of the same cell, and this asymmetry is required for endodermal remodeling and lateral root initiation. We identify that MICROTUBULE ASSOCIATED PROTEIN 70-5 (MAP70-5) is necessary for the establishment of this spatially defined microtubule organization and endodermis remodeling and thus contributes to lateral root morphogenesis. We propose that MAP70-5 and cortical microtubule arrays in the endodermis integrate the mechanical signals generated by lateral root outgrowth, facilitating the channeling of organogenesis

Poverty-Related Adversity and Emotion Regulation Predict Internalizing Behavior Problems among Low-Income Children Ages 8–11

The current study examines the additive and joint roles of chronic poverty-related adversity and three candidate neurocognitive processes of emotion regulation (ER)—including: (i) attention bias to threat (ABT); (ii) accuracy of facial emotion appraisal (FEA); and (iii) negative affect (NA)—for low-income, ethnic minority children’s internalizing problems (N = 338). Children were enrolled in the current study from publicly funded preschools, with poverty-related adversity assessed at multiple time points from early to middle childhood. Field-based administration of neurocognitively-informed assessments of ABT, FEA and NA as well as parental report of internalizing symptoms were collected when children were ages 8–11, 6 years after baseline. Results suggest that chronic exposure to poverty-related adversity from early to middle childhood predicted higher levels of internalizing symptomatology when children are ages 8–11, even after controlling for initial poverty status and early internalizing symptoms in preschool. Moreover, each of the 3 hypothesized components of ER played an independent and statistically significant role in predicting children’s parent-reported internalizing symptoms at the 6-year follow-up, even after controlling for early and chronic poverty-related adversit

Diffusible repression of cytokinin signalling produces endodermal symmetry and passage cells.

In vascular plants, the root endodermis surrounds the central vasculature as a protective sheath that is analogous to the polarized epithelium in animals, and contains ring-shaped Casparian strips that restrict diffusion. After an initial lag phase, individual endodermal cells suberize in an apparently random fashion to produce 'patchy' suberization that eventually generates a zone of continuous suberin deposition. Casparian strips and suberin lamellae affect paracellular and transcellular transport, respectively. Most angiosperms maintain some isolated cells in an unsuberized state as so-called 'passage cells', which have previously been suggested to enable uptake across an otherwise-impermeable endodermal barrier. Here we demonstrate that these passage cells are late emanations of a meristematic patterning process that reads out the underlying non-radial symmetry of the vasculature. This process is mediated by the non-cell-autonomous repression of cytokinin signalling in the root meristem, and leads to distinct phloem- and xylem-pole-associated endodermal cells. The latter cells can resist abscisic acid-dependent suberization to produce passage cells. Our data further demonstrate that, during meristematic patterning, xylem-pole-associated endodermal cells can dynamically alter passage-cell numbers in response to nutrient status, and that passage cells express transporters and locally affect the expression of transporters in adjacent cortical cells

A suberized exodermis is required for tomato drought tolerance.

Plant roots integrate environmental signals with development using exquisite spatiotemporal control. This is apparent in the deposition of suberin, an apoplastic diffusion barrier, which regulates flow of water, solutes and gases, and is environmentally plastic. Suberin is considered a hallmark of endodermal differentiation but is absent in the tomato endodermis. Instead, suberin is present in the exodermis, a cell type that is absent in the model organism Arabidopsis thaliana. Here we demonstrate that the suberin regulatory network has the same parts driving suberin production in the tomato exodermis and the Arabidopsis endodermis. Despite this co-option of network components, the network has undergone rewiring to drive distinct spatial expression and with distinct contributions of specific genes. Functional genetic analyses of the tomato MYB92 transcription factor and ASFT enzyme demonstrate the importance of exodermal suberin for a plant water-deficit response and that the exodermal barrier serves an equivalent function to that of the endodermis and can act in its place

Human domination of the global water cycle absent from depictions and perceptions

International audienceHuman water use, climate change and land conversion have created a water crisis for billions of individuals and many ecosystems worldwide. Global water stocks and fluxes are estimated empirically and with computer models, but this information is conveyed to policymakers and researchers through water cycle diagrams. Here we compiled a synthesis of the global water cycle, which we compared with 464 water cycle diagrams from around the world. Although human freshwater appropriation now equals half of global river discharge, only 15% of the water cycle diagrams depicted human interaction with water. Only 2% of the diagrams showed climate change or water pollution—two of the central causes of the global water crisis—which effectively conveys a false sense of water security. A single catchment was depicted in 95% of the diagrams, which precludes the representation of teleconnections such as ocean–land interactions and continental moisture recycling. These inaccuracies correspond with specific dimensions of water mismanagement, which suggest that flaws in water diagrams reflect and reinforce the misunderstanding of global hydrology by policymakers, researchers and the public. Correct depictions of the water cycle will not solve the global water crisis, but reconceiving this symbol is an important step towards equitable water governance, sustainable development and planetary thinking in the Anthropocene

A water cycle for the Anthropocene

International audienceHumor us for a minute and do an online image search of the water cycle. How many diagrams do you have to scroll through before seeing any sign of humans? What about water pollution or climate change—two of the main drivers of the global water crisis? In a recent analysis of more than 450 water cycle diagrams, we found that 85% showed no human interaction with the water cycle and 98% omitted any sign of climate change or waterpollution (Abbott et al., 2019). Additionally, 92% of diagrams depicted verdant, temperate ecosystems with abundant freshwater and 95% showed only a single river basin. It did not matter if the diagrams came from textbooks, scientific articles, or the internet, nor if they were old or new; most showed an undisturbed water cycle, free from human interference. These depictions contrast starkly with the state of the water cycle in the Anthropocene, when land conversion, human water use, and climate change affect nearly every water pool and flux (Wurtsbaugh et al., 2017; Falkenmark et al., 2019; Wine and Davison, 2019). The dimensions and scale of human interference with water are manifest in failing fossil aquifersin the world’s great agricultural regions (Famiglietti, 2014), accelerating ice discharge from the Arctic (Box et al., 2018), and instability in atmospheric rivers that support continental rainfall (Paul et al., 2016).We believe that incorrect water cycle diagrams are a symptom of a much deeper and widespread problem about how humanity relates to water on Earth. Society does not understand how the water cycle works nor how humans fit into it (Attari, 2014; Linton, 2014; Abbott et al., 2019). In response to this crisis of understanding, we call on researchers, educators, journalists, lawyers, and policy makers to change how we conceptualize and present the global water cycle. Specifically, we must teach where water comes from, what determines its availability, and how many individuals and ecosystems are in crisis because of water mismanagement, climate change, and land conversion. Because the drivers of the global water crisis are truly global, ensuring adequate water for humans and ecosystems will require coordinated efforts that extend beyond geopolitical borders and outlast the tenure of individual administrations (Keys et al., 2017; Adler, 2019). This level of coordination and holistic thinking requires widespread understanding of the water cycle and the global water crisis. Making the causes and consequences of the water crisis visible in our diagrams is atractable and important step towards the goal of a sustainable relationship with water that includes ecosystems and society

Gibberellin-mediated RGA-LIKE1 degradation regulates embryo sac development in Arabidopsis

[EN] Ovule development is essential for plant survival, as it allows correct embryo and seed development upon fertilization. The female gametophyte is formed in the central area of the nucellus during ovule development, in a complex developmental programme that involves key regulatory genes and the plant hormones auxins and brassinosteroids. Here we provide novel evidence of the role of gibberellins (GAs) in the control of megagametogenesis and embryo sac development, via the GA-dependent degradation of RGA-LIKE1 (RGL1) in the ovule primordia. YPet-rgl1.17 plants, which express a dominant version of RGL1, showed reduced fertility, mainly due to altered embryo sac formation that varied from partial to total ablation. YPet-rgl1.17 ovules followed normal development of the megaspore mother cell, meiosis, and formation of the functional megaspore, but YPet-rgl1.17 plants had impaired mitotic divisions of the functional megaspore. This phenotype is RGL1-specific, as it is not observed in any other dominant mutants of the DELLA proteins. Expression analysis of YPet-rgl1.17 coupled to in situ localization of bioactive GAs in ovule primordia led us to propose a mechanism of GA-mediated RGL1 degradation that allows proper embryo sac development. Taken together, our data unravel a novel specific role of GAs in the control of female gametophyte development.We wish to thank the IBMCP microscopy facility, and Ms J. Yun for technical assistance. We also thank Jennifer Nemhauser (University of Washington, USA) for the HACR sensor. Cambridge proofreading (https://proofreading.org/order/) provided proofreading and editing of this manuscript. This work was supported by grants from the Spanish Ministry for Science and Innovation-FEDER [BIO2017-83138R] to MAP-A and National Science Foundation [MCB-0923727] to JMA. MAP-A received a fellowship of the `Salvador de Madariaga' program from Spanish Ministry of Science and Innovation. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).Gomez, MD.; Barro-Trastoy, D.; Fuster Almunia, C.; Tornero Feliciano, P.; Alonso, JM.; Perez Amador, MA. (2020). Gibberellin-mediated RGA-LIKE1 degradation regulates embryo sac development in Arabidopsis. Journal of Experimental Botany. 71(22):7059-7072. https://doi.org/10.1093/jxb/eraa395S705970727122Bai, M.-Y., Shang, J.-X., Oh, E., Fan, M., Bai, Y., Zentella, R., … Wang, Z.-Y. (2012). Brassinosteroid, gibberellin and phytochrome impinge on a common transcription module in Arabidopsis. Nature Cell Biology, 14(8), 810-817. doi:10.1038/ncb2546Battaglia, R., Brambilla, V., & Colombo, L. (2008). Morphological analysis of female gametophyte development in thebel1 stk shp1 shp2mutant. 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Proceedings of the National Academy of Sciences, 98(24), 14162-14167. doi:10.1073/pnas.251534098Ferreira, L. G., de Alencar Dusi, D. M., Irsigler, A. S. T., Gomes, A. C. M. M., Mendes, M. A., Colombo, L., & de Campos Carneiro, V. T. (2017). GID1 expression is associated with ovule development of sexual and apomictic plants. Plant Cell Reports, 37(2), 293-306. doi:10.1007/s00299-017-2230-0Fleck, B., & Harberd, N. P. (2002). Evidence that theArabidopsisnuclear gibberellin signalling protein GAI is not destabilised by gibberellin. The Plant Journal, 32(6), 935-947. doi:10.1046/j.1365-313x.2002.01478.xGallego-Bartolome, J., Minguet, E. G., Grau-Enguix, F., Abbas, M., Locascio, A., Thomas, S. G., … Blazquez, M. A. (2012). Molecular mechanism for the interaction between gibberellin and brassinosteroid signaling pathways in Arabidopsis. Proceedings of the National Academy of Sciences, 109(33), 13446-13451. doi:10.1073/pnas.1119992109Gallego-Bartolome, J., Minguet, E. G., Marin, J. A., Prat, S., Blazquez, M. A., & Alabadi, D. (2010). Transcriptional Diversification and Functional Conservation between DELLA Proteins in Arabidopsis. Molecular Biology and Evolution, 27(6), 1247-1256. doi:10.1093/molbev/msq012Gomez, M. D., Barro-Trastoy, D., Escoms, E., Saura-Sánchez, M., Sánchez, I., Briones-Moreno, A., … Perez-Amador, M. A. (2018). Gibberellins negatively modulate ovule number in plants. Development. doi:10.1242/dev.163865G�mez, M. D., Beltr�n, J.-P., & Ca�as, L. A. (2004). The pea END1 promoter drives anther-specific gene expression in different plant species. Planta, 219(6), 967-981. doi:10.1007/s00425-004-1300-zGómez, M. D., Fuster-Almunia, C., Ocaña-Cuesta, J., Alonso, J. M., & Pérez-Amador, M. A. (2019). RGL2 controls flower development, ovule number and fertility in Arabidopsis. Plant Science, 281, 82-92. doi:10.1016/j.plantsci.2019.01.014Gomez, M. D., Ventimilla, D., Sacristan, R., & Perez-Amador, M. A. (2016). 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Gibberellin regulates Arabidopsis seed germination via RGL2, a GAI/RGA-like gene whose expression is up-regulated following imbibition. Genes & Development, 16(5), 646-658. doi:10.1101/gad.969002Li, Q.-F., Wang, C., Jiang, L., Li, S., Sun, S. S. M., & He, J.-X. (2012). An Interaction Between BZR1 and DELLAs Mediates Direct Signaling Crosstalk Between Brassinosteroids and Gibberellins in Arabidopsis. Science Signaling, 5(244). doi:10.1126/scisignal.2002908Lieber, D., Lora, J., Schrempp, S., Lenhard, M., & Laux, T. (2011). Arabidopsis WIH1 and WIH2 Genes Act in the Transition from Somatic to Reproductive Cell Fate. Current Biology, 21(12), 1009-1017. doi:10.1016/j.cub.2011.05.015Lora, J., Herrero, M., Tucker, M. R., & Hormaza, J. I. (2016). The transition from somatic to germline identity shows conserved and specialized features during angiosperm evolution. New Phytologist, 216(2), 495-509. doi:10.1111/nph.14330Murashige, T., & Skoog, F. (1962). 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Cell-by-cell dissection of phloem development links a maturation gradient to cell specialization

Publisher Copyright: Copyright © 2021 The Authors, some rights reserved;In the plant meristem, tissue-wide maturation gradients are coordinated with specialized cell networks to establish various developmental phases required for indeterminate growth. Here, we used single-cell transcriptomics to reconstruct the protophloem developmental trajectory from the birth of cell progenitors to terminal differentiation in the Arabidopsis thaliana root. PHLOEM EARLY DNA-BINDING-WITH-ONE-FINGER (PEAR) transcription factors mediate lineage bifurcation by activating guanosine triphosphatase signaling and prime a transcriptional differentiation program. This program is initially repressed by a meristem-wide gradient of PLETHORA transcription factors. Only the dissipation of PLETHORA gradient permits activation of the differentiation program that involves mutual inhibition of early versus late meristem regulators. Thus, for phloem development, broad maturation gradients interface with cell-type-specific transcriptional regulators to stage cellular differentiation.Peer reviewe

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