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WRKY23 is a component of the transcriptional network mediating auxin feedback on PIN polarity
(2018)
Auxin is unique among plant hormones due to its directional transport that is mediated by the polarly distributed PIN auxin transporters at the plasma membrane. The canalization hypothesis proposes that the auxin feedback on its polar flow is a crucial, plant-specific mechanism mediating multiple self-organizing developmental processes. Here, we used the auxin effect on the PIN polar localization in Arabidopsis thaliana roots as a proxy for the auxin feedback on the PIN polarity during canalization. We performed microarray experiments to find regulators of this process that act downstream of auxin. We identified genes that were transcriptionally regulated by auxin in an AXR3/IAA17-and ARF7/ARF19-dependent manner. Besides the known components of the PIN polarity, such as PID and PIP5K kinases, a number of potential new regulators were detected, among which the WRKY23 transcription factor, which was characterized in more detail. Gain-and loss-of-function mutants confirmed a role for WRKY23 in mediating the auxin effect on the PIN polarity. Accordingly, processes requiring auxin-mediated PIN polarity rearrangements, such as vascular tissue development during leaf venation, showed a higher WRKY23 expression and required the WRKY23 activity. Our results provide initial insights into the auxin transcriptional network acting upstream of PIN polarization and, potentially, canalization-mediated plant development.
Biodiversity has suffered a dramatic global decline during the past decades, and monitoring tools are urgently needed providing data for the development and evaluation of conservation efforts both on a species and on a genetic level. However, in wild species, the assessment of genetic diversity is often hampered by the lack of suitable genetic markers. In this article, we present Random Amplicon Sequencing (RAMseq), a novel approach for fast and cost-effective detection of single nucleotide polymorphisms (SNPs) in nonmodel species by semideep sequencing of random amplicons. By applying RAMseq to the Eurasian otter (Lutra lutra), we identified 238 putative SNPs after quality filtering of all candidate loci and were able to validate 32 of 77 loci tested. In a second step, we evaluated the genotyping performance of these SNP loci in noninvasive samples, one of the most challenging genotyping applications, by comparing it with genotyping results of the same faecal samples at microsatellite markers. We compared (i) polymerase chain reaction (PCR) success rate, (ii) genotyping errors and (iii) Mendelian inheritance (population parameters). SNPs produced a significantly higher PCR success rate (75.5% vs. 65.1%) and lower mean allelic error rate (8.8% vs. 13.3%) than microsatellites, but showed a higher allelic dropout rate (29.7% vs. 19.8%). Genotyping results showed no deviations from Mendelian inheritance in any of the SNP loci. Hence, RAMseq appears to be a valuable tool for the detection of genetic markers in nonmodel species, which is a common challenge in conservation genetic studies.
This article describes architectural extensions for a dynamically scheduled processor to enable three different operation modes, ranging from high-performance, to high-reliability. With minor extensions of the control path, the resources of the super-scalar data-path can be used either for high-performance execution, fail-safe-operation, or fault-tolerant-operation. Furthermore, the online error-correction capabilities are combined with reconfiguration techniques for permanent fault handling. This reconfiguration can take defective components out of operation permanently, and can be triggered on-demand during runtime, depending on the frequency of online corrected faults. A comprehensive fault simulation was carried out in order to evaluate hardware overhead, fault coverage and performance penalties of the proposed approach. Moreover, the impact of the permanent reconfiguration regarding the reliability and performance is investigated.
Social participation of pupils with special educational needs (SEN) is a central topic in the current inclusion debate. Numerous studies have shown that the risk of social exclusion is considerably higher for children with SEN compared to their peers without SEN, especially for pupils with behaviour problems (BP) or learning difficulties (LD). Since most of these studies are based on cross-sectional designs, there is a lack of knowledge regarding the direction of the effects. This leads to the question to what extent BP and LD have an impact on pupils’ social position in the class and, vice versa, to what extent the social position has an effect on the development of BP and LD. To address these questions, we analysed sociometric data of 1244 primary school children. È A cross-lagged panel analysis was conducted. The results indicate that BP and LD in 1st grade lead to significantly less social acceptance by peers in 2nd grade but do not predict significantly higher social rejection. A directed influence of LD or BP on a higher social rejection cannot be found. Conversely, neither social acceptance nor social rejection at 1st grade has an influence on the development of BP or LD at grade two.
Coordinated cell polarization in developing tissues is a recurrent theme in multicellular organisms. In plants, a directional distribution of the plant hormone auxin is at the core of many developmental programs. A feedback regulation of auxin on the polarized localization of PIN auxin transporters in individual cells has been proposed as a self-organizing mechanism for coordinated tissue polarization, but the molecular mechanisms linking auxin signalling to PIN-dependent auxin transport remain unknown. We used a microarray-based approach to find regulators of the auxin-induced PIN relocation in Arabidopsis thaliana root, and identified a subset of a family of phosphatidylinositol transfer proteins (PITPs), the PATELLINs (PATLs). Here, we show that PATLs are expressed in partially overlapping cell types in different tissues going through mitosis or initiating differentiation programs. PATLs are plasma membrane-associated proteins accumulated in Arabidopsis embryos, primary roots, lateral root primordia and developing stomata. Higher order patl mutants display reduced PIN1 repolarization in response to auxin, shorter root apical meristem, and drastic defects in embryo and seedling development. This suggests that PATLs play a redundant and crucial role in polarity and patterning in Arabidopsis.
In angiosperms, the gynoecium is the last structure to develop within the flower due to the determinate fate of floral meristem (FM) stem cells. The maintenance of stem cell activity before its arrest at the stage called FM termination affects the number of carpels that develop. The necessary inhibition at this stage of WUSCHEL (WUS), which is responsible for stem cell maintenance, involves a two-step mechanism. Direct repression mediated by the MADS domain transcription factor AGAMOUS (AG), followed by indirect repression requiring the C2H2 zinc-finger protein KNUCKLES (KNU), allow for the complete termination of floral stem cell activity. Here, we show that Arabidopsis thaliana MINI ZINC FINGER2 (AtMIF2) and its homolog in tomato (Solanum lycopersicum), INHIBITOR OF MERISTEM ACTIVITY (SlIMA), participate in the FM termination process by functioning as adaptor proteins. AtMIF2 and SlIMA recruit AtKNU and SlKNU, respectively, to form a transcriptional repressor complex together with TOPLESS and HISTONE DEACETYLASE19. AtMIF2 and SlIMA bind to the WUS and SIWUS loci in the respective plants, leading to their repression. These results provide important insights into the molecular mechanisms governing (FM) termination and highlight the essential role of AtMIF2/SlIMA during this developmental step, which determines carpel number and therefore fruit size.
Studies on Oberonia 3. Aberrant flowers and other floral modifications in the orchid genus Oberonia
(2018)
Orchid flowers are amongst the most conspicuous attractions that plants have generated over evolutionary epochs. However, organ homology in particular of androecium and gynoecium of orchid flowers have been, and are still, the subject of long-term discussion. Studies of aberrant - teratologic - flowers have traditionally helped to clarify organ identity in orchids. We here present for the first time teratological flowers within the florally smallest and inconspicuous orchid genus Oberonia and illustrate them by light and scanning electron microscopy. Pseudopeloria with half of a lateral petal transformed into a lip was found in O. costeriana J.J.Sm. and O. mucronata (D.Don) Ormerod & Seidenf. A supernumerary lip is known from O. mucronata. Oberonia rufilabris Lindl. is documented with multiple aberrations: triple gynostemium and a total of 10 tepals, twin flowers, and duplicate lips. We interpret these aberrations in light of known floral developmental and organ identity information.
The ratio of the proton ring velocity (VR) to the local Alfven speed (VA), in addition to proton ring distributions, plays a key factor in the excitation of magnetosonic waves at frequencies between the proton cyclotron frequency fcp and the lower hybrid resonance frequency fLHR in the Earth's magnetosphere. Here we investigate whether there is a statistically significant relationship between occurrences of proton rings and magnetosonic waves both outside and inside the plasmapause using particle and wave data from Van Allen Probe-A during the time period of October 2012 to December 2015. We also perform a statistical survey of the ratio of the ring energy (ER, corresponding to VR) to the Alfven energy (EA, corresponding to VA) to determine the favorable conditions under which magnetosonic waves in each of two frequency bands (fcp < f ≤ 0.5 fLHR and 0.5 fLHR < f < fLHR) can be excited. The results show that the magnetosonic waves in both frequency bands occur around the postnoon (12–18 magnetic local time, MLT) sector outside the plasmapause when ER is comparable to or lower than EA, and those in lower-frequency bands (fcp < f ≤ 0.5 fLHR) occur around the postnoon sector inside the plasmapause when ER/EA > ~9. However, there is one discrepancy between occurrences of proton rings and magnetosonic waves in low-frequency bands around the prenoon sector (6–12 MLT) outside the plasmapause, which suggests either that the waves may have propagated during active time from the postnoon sector after being excited during quiet time, or they may have locally excited in the prenoon sector during active time.
Background/Aims: Gestational diabetes (GDM) might be associated with alterations in the metabolomic profile of affected mothers and their offspring. Until now, there is a paucity of studies that investigated both, the maternal and the fetal serum metabolome in the setting of GDM. Mounting evidence suggests that the fetus is not just passively affected by gestational disease but might play an active role in it. Metabolomic studies performed in maternal blood and fetal cord blood could help to better discern distinct fetal from maternal disease interactions. Methods: At the time of birth, serum samples from mothers and newborns (cord blood samples) were collected and screened for 163 metabolites utilizing tandem mass spectrometry. The cohort consisted of 412 mother/child pairs, including 31 cases of maternal GDM. Results: An initial non-adjusted analysis showed that eight metabolites in the maternal blood and 54 metabolites in the cord blood were associated with GDM. After Benjamini-Hochberg (BH) procedure and adjustment for confounding factors for GDM, fetal phosphatidylcholine acyl-alkyl C 32:1 and proline still showed an independent association with GDM. Conclusions: This study found metabolites in cord blood which were associated with GDM, even after adjustment for established risk factors of GDM. To the best of our knowledge, this is the first study demonstrating an independent association between fetal serum metabolites and maternal GDM. Our findings might suggest a potential effect of the fetal metabolome on maternal GDM. (c) 2018 The Author(s) Published by S. Karger AG, Basel
Background/Aims: Impaired birth outcomes, like low birth weight, have consistently been associated with increased disease susceptibility to hypertension in later life. Alterations in the maternal or fetal metabolism might impact on fetal growth and influence birth outcomes. Discerning associations between the maternal and fetal metabolome and surrogate parameters of fetal growth could give new insight into the complex relationship between intrauterine conditions, birth outcomes, and later life disease susceptibility. Methods: Using flow injection tandem mass spectrometry, targeted metabolomics was performed in serum samples obtained from 226 mother/child pairs at delivery. Associations between neonatal birth weight and concentrations of 163 maternal and fetal metabolites were analyzed. Results: After FDR adjustment using the Benjamini-Hochberg procedure lysophosphatidylcholines (LPC) 14:0, 16:1, and 18:1 were strongly positively correlated with birth weight. In a stepwise linear regression model corrected for established confounding factors of birth weight, LPC 16: 1 showed the strongest independent association with birth weight (CI: 93.63 - 168.94; P = 6.94x10(-11)). The association with birth weight was stronger than classical confounding factors such as offspring sex (CI: - 258.81- -61.32; P = 0.002) and maternal smoking during pregnancy (CI: -298.74 - -29.51; P = 0.017). Conclusions: After correction for multiple testing and adjustment for potential confounders, LPC 16:1 showed a very strong and independent association with birth weight. The underlying molecular mechanisms linking fetal LPCs with birth weight need to be addressed in future studies. (c) 2018 The Author(s) Published by S. Karger AG, Basel
Snow meltwaters account for most of the yearly water budgets of many catchments in High Mountain Asia (HMA). We examine trends in snow water equivalent (SWE) using passive microwave data (1987 to 2009). We find an overall decrease in SWE in HMA, despite regions of increased SWE in the Pamir, Kunlun Shan, Eastern Himalaya, and Eastern Tien Shan. Although the average decline in annual SWE across HMA (contributing area, 2641 x 10(3) km(2)) is low (average, -0.3%), annual SWE losses conceal distinct seasonal and spatial heterogeneities across the study region. For example, the Tien Shan has seen both strong increases in winter SWE and sharp declines in spring and summer SWE. In the majority of catchments, the most negative SWE trends are found in mid-elevation zones, which often correspond to the regions of highest snow-water storage and are somewhat distinct from glaciated areas. Negative changes in SWE storage in these mid-elevation zones have strong implications for downstream water availability.
A growing number of health-conscious individuals supplements their diet with protein-rich plant-based products to reduce their meat consumption. Analytical methods are needed to authenticate these new vegetarian products not only for the correct labelling of ingredients according to European legislation but also to discourage food fraud. This paper presents new biomarkers for a targeted proteomics LC-MS/MS work-flow that can simultaneously prove the presence/absence of garden pea, a protein-rich legume, meat and honey and quantify their content in processed vegan food. We show a novel rapid strategy to identify biomarkers for species authentication and the steps for the multi-parameter LC-MS/MS method validation and quantification. A high resolution triple time of flight mass spectrometer (HRMS) with SWATH Acquisition was used for the rapid discovery of all measurable trypsin-digested proteins in the individual ingredients. From these proteins, species-selective biomarkers were identified with BLAST and Skyline. Vicilin and convicilin (UniProt: D3VND9, Q9M3X6) allow pea authentication with regard to other legume species. Myostatin (UniProt: 018831) is a single biomarker for all meat types. For honey, we identified three selective proteins (UniProt: C6K481, C6K482, Q3L6329). The final LC-MS/MS method can identity and quantify these markers simultaneously. Quantification occurs via external matrix calibration.
A weight normalization procedure, commonly called pushing, is introduced for weighted tree automata (wta) over commutative semifields. The normalization preserves the recognized weighted tree language even for nondeterministic wta, but it is most useful for bottom-up deterministic wta, where it can be used for minimization and equivalence testing. In both applications a careful selection of the weights to be redistributed followed by normalization allows a reduction of the general problem to the corresponding problem for bottom-up deterministic unweighted tree automata. This approach was already successfully used by Mohri and Eisner for the minimization of deterministic weighted string automata. Moreover, the new equivalence test for two wta M and M′ runs in time O((|M|+|M′|)⋅log(|Q|+|Q′|)), where Q and Q′ are the states of M and M′, respectively, which improves the previously best run-time O(|M|⋅|M′|).
Purpose
The purpose of this paper is to discuss different approaches of performance measurement and benchmarking as reflexive institutions for local governments in England, Germany and Sweden from a comparative perspective.
Design/methodology/approach
These three countries have been selected because they represent typical (most different) cases of European local government systems and reforms. The existing theories on institutional reflexivity point to the potential contribution of benchmarking to public sector innovation and organizational learning. Based on survey findings, in-depth case studies, interviews and document analyses in these three countries, the paper addresses the major research question as to what extent and why benchmarking regimes vary across countries. It derives hypotheses about the impacts of benchmarking on institutional learning and innovation.
Findings
The outcomes suggest that the combination of three key features of benchmarking, namely - obligation, sanctions and benchmarking authority - in conjunction with country-specific administrative context conditions and local actor constellations - influences the impact of benchmarking as a reflexive institution.
Originality/value
It is shown in the paper that compulsory benchmarking on its own does not lead to reflexivity and learning, but that there is a need for autonomy and leeway for local actors to cope with benchmarking results. These findings are relevant because policy makers must decide upon the specific governance mix of benchmarking exercises taking their national and local contexts into account if they want them to promote institutional learning and innovation.
Research provides evidence that gender, immigrant background and socio-economic characteristics present multiple disadvantaging characteristics that change their relative importance and configurations over time. When evaluating inequalities researchers tend to focus on one particular aspect and often use composite measures when evaluating socio-economic characteristics. Neither can fully represent the complexity of students’ various disadvantaging characteristics, which have autonomous associations with attainment and with each other. This paper investigates how the relative importance and configurations of different disadvantaging factors have changed over time to form educational inequalities and how these changes differ across countries. Data from five PISA cycles (2000–2012) for France, Germany, Sweden and the United Kingdom are used and configurations of gender, immigration background, parents’ occupational and educational levels, and the number of books at home evaluated. Results enable us to relate changes (or lack thereof) in configurations of disadvantaging factors to recent reforms targeted at reducing educational inequality after the first PISA results.
Background: In probable Alzheimer’s disease (AD), different memory systems, executive functioning, visuospatial recognition, and language are impaired. Regarding the latter, only a few studies have investigated morphosyntactic production thus far.
Aims: This study, which is a follow-up on Fyndanis, V., Manouilidou, C., Koufou, E., Karampekios, S., and Tsapakis, E. M. (2013). Agrammatic patterns in Alzheimer's disease: Evidence from tense, agreement, and aspect. Aphasiology, 27, 178–200. doi:10.1080/02687038.2012.705814, investigates whether verb-related morphosyntactic production is (selectively) impaired in AD focusing on two highly inflected languages, Greek and Italian. The morphosyntactic phenomena explored are subject–verb Agreement, Tense/Time Reference, and Mood. Focusing on these phenomena allows us to investigate if recent hypotheses, originally developed in aphasia research, can also capture results related to AD. We tested the hypotheses discussed in Fyndanis, V., Manouilidou, C., Koufou, E., Karampekios, S., and Tsapakis, E. M. (2013). Agrammatic patterns in Alzheimer's disease: Evidence from tense, agreement, and aspect. Aphasiology, 27, 178–200. doi:10.1080/02687038.2012.705814, that is, the Interpretable Features’ Impairment Hypothesis (IFIH) (e.g., Fyndanis, V., Varlokosta, S., & Tsapkini, K. 2012. Agrammatic production: Interpretable features and selective impairment in verb inflection. Lingua, 122, 1134–1147. doi:10.1016/j.lingua.2012.05.004) and the PAst DIscourse LInking Hypothesis (PADILIH; Bastiaanse, R., Bamyaci, E., Hsu, C., Lee, J., Yarbay Duman, T., & Thompson, C. K. 2011. Time reference in agrammatic aphasia: A cross-linguistic study. Journal of Neurolinguistics, 24, 652–673. doi:10.1016/j.jneuroling.2011.07.001).
Methods & Procedures: Two sentence completion tasks testing the production of subject-verb Agreement, Tense/Time Reference, and Mood were administered to 16 Greek-speaking and 10 Italian-speaking individuals with mild-to-moderate AD, as well as to 16 Greek-speaking and 11 Italian-speaking neurologically intact individuals who were matched with the participants with AD on age and education. Mixed-effects models were fitted to the data.
Outcomes & Results: At the group level, both the Greek and Italian participants with AD performed worse than the controls. Both AD groups revealed selective patterns of morphosyntactic production (Greek: Agreement/Mood > Time Reference; Italian: Agreement > Time Reference > Mood). Past Reference and Future Reference did not dissociate in either of the two AD groups. Nevertheless, in all four participants with AD who showed dissociations, Past Reference was more impaired than Future Reference.
Conclusions: The results indicate that the production of verb-related morphosyntactic categories can be impaired in mild-to-moderate AD. The different patterns observed in the two languages are partly attributable to the different way these languages encode Mood. The group results (of both the Greek-and Italian-speaking participants with AD) do not lend support to the PADILIH, whereas only the results of the Italian AD group are fully consistent with the IFIH. However, the individual data are consistent with the PADILIH, and the IFIH is informed by the present data and modified accordingly so that it can capture cross-linguistic patterns of morphosyntactic impairment.
In connected speech, many words are produced with a pronunciation that differs from the canonical form. How the speech recognition system deals with this variation is a fundamental issue in the language processing literature. The present study examines the roles of variant type, variant frequency, and context in the processing of French words with a canonical (schwa variant, e.g. semaine “week”) and a non-canonical pronunciation (no-schwa variant, s’maine). It asks whether the processing of canonical pronunciations is faster than the processing of non-canonical ones. Results of three lexical decision experiments reveal that more frequent variants are recognised more quickly, and that there is no advantage for canonical forms once variant frequency is accounted for. Two of these experiments further failed to find evidence that the context in which the words are presented modulate the effect of variant type. These findings are discussed in the light of spoken word recognition models.
Manifolds with corners in the present investigation are non-smooth configurations - specific stratified spaces - with an incomplete metric such as cones, manifolds with edges, or corners of piecewise smooth domains in Euclidean space. We focus here on operators on such "corner manifolds" of singularity order <= 2, acting in weighted corner Sobolev spaces. The corresponding corner degenerate pseudo-differential operators are formulated via Mellin quantizations, and they also make sense on infinite singular cones.
Previous research informs us about facilitators of employees’ promotive voice. Yet little is known about what determines whether a specific idea for constructive change brought up by an employee will be approved or rejected by a supervisor. Drawing on interactionist theories of motivation and personality, we propose that a supervisor will be least likely to support an idea when it threatens the supervisor’s power motive, and when it is perceived to serve the employee’s own striving for power. The prosocial versus egoistic intentions attributed to the idea presenter are proposed to mediate the latter effect. We conducted three scenario-based studies in which supervisors evaluated fictitious ideas voiced by employees that – if implemented – would have power-related consequences for them as a supervisor. Results show that the higher a supervisors’ explicit power motive was, the less likely they were to support a power-threatening idea (Study 1, N = 60). Moreover, idea support was less likely when this idea was proposed by an employee that was described as high (rather than low) on power motivation (Study 2, N = 79); attributed prosocial intentions mediated this effect. Study 3 (N = 260) replicates these results.
Schomburgk’s Chook
(2018)
Focusing on the politics of museums, collections and the untold stories of the scientific ‘specimens’ that travelled between Germany and Australia, this article reconstructs the historical, interpersonal and geopolitical contexts that made it possible for the stuffed skin of an Australian malleefowl to become part of the collections of Berlin’s Museum für Naturkunde. The author enquires into the kinds of contexts that are habitually considered irrelevant when a specimen of natural history is treated as an object of taxonomic information only. In case of this particular specimen human and non-human history become entangled in ways that link the fate of this one small Australian bird to the German revolutionary generation of 1848, to Germany’s nineteenth-century colonial aspirations, to settler–Indigenous relations, to the cruel realities that underpinned the production of scientific knowledge in colonial Australia, and to a present-day interest in reconstructing Indigenous knowledges.