The Geometry of Axisymmetric Ideal Fluid Flows with Swirl

The sectional curvature of the volume preserving diffeomorphism group of a Riemannian manifold $M$ can give information about the stability of inviscid, incompressible fluid flows on $M$. We demonstrate that the submanifold of the volumorphism group of the solid flat torus generated by axisymmetric fluid flows with swirl, denoted by $\mathcal{D}_{\mu,E}(M)$, has positive sectional curvature in every section containing the field $X = u(r)\partial_\theta$ iff $\partial_r(ru^2)>0$. This is in sharp contrast to the situation on $\mathcal{D}_{\mu}(M)$, where only Killing fields $X$ have nonnegative sectional curvature in all sections containing it. We also show that this criterion guarantees the existence of conjugate points on $\mathcal{D}_{\mu,E}(M)$ along the geodesic defined by $X$.Comment: 8 page

A Pure Representationalist Account of Belief and Desire

According to the traditional view, beliefs and desires are mental representations that play particular functional roles. A belief that P is state which represents P and plays the belief-role, while a desire that P is a state which represents that P and plays the desire-role. In this dissertation I argue that the traditional view has trouble accounting for (a) role that belief and desire play in the causal and rational explanation of behaviour and (b) our knowledge of our own conscious, occurrent beliefs and desires. In its place I argue for Pure Attitude Representationalism (PAR), which holds that beliefs and desires are not to be distinguished from one another by their functional role, but instead entirely by their representational content. According to PAR, desires are distinct from beliefs not because they do different things, but because desires represent things as being rewarding. Throughout the three papers that comprise this dissertation I argue that PAR provides a better explanation of (a) and (b)

Supporting bereavement and complicated grief in primary care: a realist review.

BACKGROUND: Bereavement can have significant impacts on physical and mental health, and a minority of people experience complicated and prolonged grief responses. Primary care is ideally situated to offer bereavement care, yet UK provision remains variable and practitioners feel uncertain how best to support bereaved patients. AIM: To identify what works, how, and for whom, in the management of complicated grief (CG) in primary care. DESIGN & SETTING: A review of evidence on the management of CG and bereavement in UK primary care settings. METHOD: A realist approach was taken that aims to provide causal explanations through the generation and articulation of contexts, mechanisms, and outcomes. RESULTS: Forty-two articles were included. Evidence on the primary care management of complicated or prolonged grief was limited. GPs and nurses view bereavement support as part of their role, yet experience uncertainty over the appropriate extent of their involvement. Patients and clinicians often have differing views on the role of primary care in bereavement. Training in bereavement, local systems for reporting deaths, practitioner time, and resources can assist or hinder bereavement care provision. Practitioners find bereavement care can be emotionally challenging. Understanding patients' needs can encourage a proactive response and help identify appropriate support. CONCLUSION: Bereavement care in primary care remains variable and practitioners feel unprepared to provide appropriate bereavement care. Patients at higher risk of complicated or prolonged grief may fail to receive the support they need from primary care. Further research is required to address the potential unmet needs of bereaved patients

Per-alkoxy-pillar[5]arenes as electron donors: Electrochemical properties of dimethoxy-pillar[5]arene and its corresponding rotaxane

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). 1,4-dimethoxypillar[5]arene undergoes reversible multielectron oxidations forming stable radical cations, a property retained when incorporated in [2]rotaxanes, suggesting that pillar[5]arenes can be employed as viable, yet unreported, electron donors

Highly conserved motifs in non-coding regions of Sirevirus retrotransposons: the key for their pattern of distribution within and across plants?

<p>Abstract</p> <p>Background</p> <p>Retrotransposons are key players in the evolution of eukaryotic genomes. Moreover, it is now known that some retrotransposon classes, like the abundant and plant-specific Sireviruses, have intriguingly distinctive host preferences. Yet, it is largely unknown if this bias is supported by different genome structures.</p> <p>Results</p> <p>We performed sensitive comparative analysis of the genomes of a large set of Ty1/<it>copia </it>retrotransposons. We discovered that Sireviruses are unique among <it>Pseudoviridae </it>in that they constitute an ancient genus characterized by vastly divergent members, which however contain highly conserved motifs in key non-coding regions: multiple polypurine tract (PPT) copies cluster upstream of the 3' long terminal repeat (3'LTR), of which the terminal PPT tethers to a distinctive attachment site and is flanked by a precisely positioned inverted repeat. Their LTRs possess a novel type of repeated motif (RM) defined by its exceptionally high copy number, symmetry and core CGG-CCG signature. These RM boxes form CpG islands and lie a short distance upstream of a conserved promoter region thus hinting towards regulatory functions. Intriguingly, in the envelope-containing Sireviruses additional boxes cluster at the 5' vicinity of the envelope. The 5'LTR/internal domain junction and a polyC-rich integrase signal are also highly conserved domains of the Sirevirus genome.</p> <p>Conclusions</p> <p>Our comparative analysis of retrotransposon genomes using advanced <it>in silico </it>methods highlighted the unique genome organization of Sireviruses. Their structure may dictate a life cycle with different regulation and transmission strategy compared to other <it>Pseudoviridae</it>, which may contribute towards their pattern of distribution within and across plants.</p

Using cGANs for Anomaly Detection: Identifying Astronomical Anomalies in JWST NIRcam Imaging

We present a proof of concept for mining JWST imaging data for anomalous galaxy populations using a conditional Generative Adversarial Network (cGAN). We train our model to predict long wavelength NIRcam fluxes (LW: F277W, F356W, F444W between 2.4 to 5.0\mu m) from short wavelength fluxes (SW: F115W, F150W, F200W between 0.6 to 2.3\mu m) in approximately 2000 galaxies. We test the cGAN on a population of 37 Extremely Red Objects (EROs) discovered by the CEERS JWST Team arXiv:2305.14418. Despite their red long wavelength colours, the EROs have blue short wavelength colours (F150W \- F200W equivalently 0 mag) indicative of bimodal SEDs. Surprisingly, given their unusual SEDs, we find that the cGAN accurately predicts the LW NIRcam fluxes of the EROs. However, it fails to predict LW fluxes for other rare astronomical objects, such as a merger between two galaxies, suggesting that the cGAN can be used to detect some anomaliesComment: 4 pages, 1 figure with 5 sub-figures. Submitted, accepted and awaiting publication in AAS Journal

Regulation of Zn and Fe transporters by the GPC1 gene during early wheat monocarpic senescence

BACKGROUND: During wheat senescence, leaf components are degraded in a coordinated manner, releasing amino acids and micronutrients which are subsequently transported to the developing grain. We have previously shown that the simultaneous downregulation of Grain Protein Content (GPC) transcription factors, GPC1 and GPC2, greatly delays senescence and disrupts nutrient remobilization, and therefore provide a valuable entry point to identify genes involved in micronutrient transport to the wheat grain. RESULTS: We generated loss-of-function mutations for GPC1 and GPC2 in tetraploid wheat and showed in field trials that gpc1 mutants exhibit significant delays in senescence and reductions in grain Zn and Fe content, but that mutations in GPC2 had no significant effect on these traits. An RNA-seq study of these mutants at different time points showed a larger proportion of senescence-regulated genes among the GPC1 (64%) than among the GPC2 (37%) regulated genes. Combined, the two GPC genes regulate a subset (21.2%) of the senescence-regulated genes, 76.1% of which are upregulated at 12 days after anthesis, before the appearance of any visible signs of senescence. Taken together, these results demonstrate that GPC1 is a key regulator of nutrient remobilization which acts predominantly during the early stages of senescence. Genes upregulated at this stage include transporters from the ZIP and YSL gene families, which facilitate Zn and Fe export from the cytoplasm to the phloem, and genes involved in the biosynthesis of chelators that facilitate the phloem-based transport of these nutrients to the grains. CONCLUSIONS: This study provides an overview of the transport mechanisms activated in the wheat flag leaf during monocarpic senescence. It also identifies promising targets to improve nutrient remobilization to the wheat grain, which can help mitigate Zn and Fe deficiencies that afflict many regions of the developing world.Fil: Pearce, Stephen. University of California; Estados UnidosFil: Tabbita, Facundo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; ArgentinaFil: Cantu, Dario. University of California; Estados UnidosFil: Buffalo, Vince. University of California; Estados UnidosFil: Avni, Raz. Tel Aviv University; IsraelFil: Vazquez Gross, Hans. University of California; Estados UnidosFil: Zhao, Rongrong. China Agricultural University; ChinaFil: Conley, Christopher J.. University of California; Estados UnidosFil: Distelfeld, Assaf. Faculty Of Life Sciences, Department Of Molecular Biolo;Fil: Dubcovsky, Jorge. University of California; Estados Unidos. Howard Hughes Medical Institute ; Estados Unidos. Gordon & Betty Moore Foundation Investigator; Estados Unido

Effect of the Hope FT-B1 Allele on wheat heading time and yield components

Precise regulation of flowering time is critical for plant reproductive success and, in cereals, to maximize grain yields. Seasonal cues including temperature and day length are integrated to regulate the timing of flowering. In temperate cereals, extended periods of cold (vernalization) release the repression of FLOWERING LOCUS T1 (FT1), which is upregulated in the leaves in response to inductive long-day photoperiods. FT1 is a homolog of rice HD3a, which encodes a protein transported from leaves to the shoot apical meristem to induce flowering. A rare FT-B1 allele from the wheat variety “Hope” has been previously shown to be associated with an early flowering phenotype under long-day photoperiods. Here, we demonstrate that the Hope FT-B1 allele accelerates flowering even under short days, and that it is epistatic to the VERNALIZATION 1 (VRN1) gene. On average, the introgression of Hope FT-B1 into 6 genetic backgrounds resulted in 2.6 days acceleration of flowering (P < 0.0001) and 4.1% increase in spike weight (P = 0.0093), although in one variety, it was associated with a decrease in spike weight. These results suggest that the Hope FT-B1 allele could be useful in wheat breeding programs to subtly accelerate floral development and increase adaptation to changing environments.Fil: Nitcher, Rebecca. University of California. Department of Plant Sciences; Estados UnidosFil: Pearce, Stephen. University of California. Department of Plant Sciences; Estados UnidosFil: Tranquilli, Gabriela. University of California. Department of Plant Sciences; Estados Unidos. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Recursos Biológicos; ArgentinaFil: Xiaoqin, Zhang. University of California. Department of Plant Sciences; Estados UnidosFil: Dubcovsky, Jorge. University of California. Department of Plant Sciences; Estados Unidos. Howard Hughes Medical Institute; Estados Unido