171 research outputs found
New State Record of the Psyllid Heterotrioza chenopodii (Reuter, 1876) (Hemiptera: Psylloidea: Triozidae) for Hawaii
We report the first state record of a widespread palaearctic psyllid species, Heterotrioza chenopodii (Reuter, 1876), for the state of Hawaii. This species belongs to a small genus of 13 species feeding exclusively on host plants in the plant family Amaranthaceae (Lauterer 1982, Burckhardt and Ouvrard 2012, Ouvrard 2019). Recorded host genera are Atriplex, Beta, Chenopodium, and Spinacia (Ouvrard 2019). In Hawaii, a likely host plant is Atriplex suberecta, and possibly A. semibaccata and Chenopodium oahuense
Catalog of Galactic Beta Cephei Stars
We present an extensive and up-to-date catalog of Galactic Beta Cephei stars.
This catalog is intended to give a comprehensive overview of observational
characteristics of all known Beta Cephei stars. 93 stars could be confirmed to
be Beta Cephei stars. For some stars we re-analyzed published data or conducted
our own analyses. 61 stars were rejected from the final Beta Cephei list, and
77 stars are suspected to be Beta Cephei stars. A list of critically selected
pulsation frequencies for confirmed Beta Cephei stars is also presented. We
analyze the Beta Cephei stars as a group, such as the distributions of their
spectral types, projected rotational velocities, radial velocities, pulsation
periods, and Galactic coordinates. We confirm that the majority of these stars
are multiperiodic pulsators. We show that, besides two exceptions, the Beta
Cephei stars with high pulsation amplitudes are slow rotators. We construct a
theoretical HR diagram that suggests that almost all 93 Beta Cephei stars are
MS objects. We discuss the observational boundaries of Beta Cephei pulsation
and their physical parameters. We corroborate that the excited pulsation modes
are near to the radial fundamental mode in frequency and we show that the mass
distribution of the stars peaks at 12 solar masses. We point out that the
theoretical instability strip of the Beta Cephei stars is filled neither at the
cool nor at the hot end and attempt to explain this observation
The phenotype associated with a large deletion on MECP2
Multiplex ligation-dependent Probe Amplification (MLPA) has become available for the detection of a large deletion on the MECP2 gene allowing genetic confirmation of previously unconfirmed cases of clinical Rett syndrome. This study describes the phenotype of those with a large deletion and compares with those with other pathogenic MECP2 mutations. Individuals were ascertained from the Australian Rett Syndrome and InterRett databases with data sourced from family and clinician questionnaires, and two case studies were constructed from the longitudinal Australian data. Regression and survival analysis were used to compare severity and age of onset of symptoms in those with and without a large deletion. Data were available for 974 individuals including 51 with a large deletion and ages ranged from 1 year 4 months to 49 years (median 9 years). Those with a large deletion were more severely affected than those with other mutation types. Specifically, individuals with large deletions were less likely to have learned to walk (OR 0.42, 95% CI: 0.22–0.79, P=0.007) and to be currently walking (OR 0.53, 95% CI: 0.26–1.10, P=0.089), and were at higher odds of being in the most severe category of gross motor function (OR 1.84, 95% CI: 0.98–3.48, P=0.057) and epilepsy (OR 2.72, 95% CI: 1.38–5.37, P=0.004). They also developed epilepsy, scoliosis, hand stereotypies and abnormal breathing patterns at an earlier age. We have described the disorder profile associated with a large deletion from the largest sample to date and have found that the phenotype is severe with motor skills particularly affected
The private military industry and neoliberal imperialism: Mapping the terrain
Despite the international reach, and increasing global importance, of the free market provision of military and security services—which we label the Private Security Industry (PSI)—management and organization studies has yet to pay significant attention to this industry. Taking up Grey’s (2009) call for scholarship at the boundaries between security studies and organization studies and building on Banerjee’s (2008) treatment of the PSI as a key element in necrocapitalism, in this article we aim to trace the long history of the PSI and argue that it has re-emerged over the last two decades against, and as a result of, a very specific politico-economic backdrop. We then suggest that the PSI operates as a mechanism for neoliberal imperialism; demonstrate its substitution for and supplementing of the state; and count some of the costs of this privatization of war. Finally, we take seriously Hughes’s (2007) thesis of the growth of a new security-industrial complex, and of the intersecting elites who benefit from this phenomenon
The art of face-saving and culture-changing: sculpting Chinese football’s past, present and future
In this paper, we consider the football statues of China, whose football team has dramatically underperformed relative to its population size and economic power. Although China lacks a participative grassroots football culture and has struggled to establish a credible domestic league, recent government intervention and investment has seen football’s profile rise dramatically. China’s many football statues are largely atypical in comparison to the rest of the world, including their depiction of anonymous figures rather than national or local heroes, the incorporation of tackling scenes in their designs, and their location at training camps. Through four specific examples and reference to a global database, we illustrate how these statues reflect the tensions and difficulties inherent in China’s desire to integrate itself into global football, and achieve its stated goal of hosting and winning the FIFA World Cup, whilst simultaneously upholding national, cultural and political values such as the primacy of hard work and learning, and saving face in defeat
Isolation of MECP2-null Rett Syndrome patient hiPS cells and isogenic controls through X-chromosome inactivation
Rett syndrome (RTT) is a neurodevelopmental autism spectrum disorder that affects girls due primarily to mutations in the gene encoding methyl-CpG binding protein 2 (MECP2). The majority of RTT patients carry missense and nonsense mutations leading to a hypomorphic MECP2, while null mutations leading to the complete absence of a functional protein are rare. MECP2 is an X-linked gene subject to random X-chromosome inactivation resulting in mosaic expression of mutant MECP2. The lack of human brain tissue motivates the need for alternative human cellular models to study RTT. Here we report the characterization of a MECP2 mutation in a classic female RTT patient involving rearrangements that remove exons 3 and 4 creating a functionally null mutation. To generate human neuron models of RTT, we isolated human induced pluripotent stem (hiPS) cells from RTT patient fibroblasts. RTT-hiPS cells retained the MECP2 mutation, are pluripotent and fully reprogrammed, and retained an inactive X-chromosome in a nonrandom pattern. Taking advantage of the latter characteristic, we obtained a pair of isogenic wild-type and mutant MECP2 expressing RTT-hiPS cell lines that retained this MECP2 expression pattern upon differentiation into neurons. Phenotypic analysis of mutant RTT-hiPS cell-derived neurons demonstrated a reduction in soma size compared with the isogenic control RTT-hiPS cell-derived neurons from the same RTT patient. Analysis of isogenic control and mutant hiPS cell-derived neurons represents a promising source for understanding the pathogenesis of RTT and the role of MECP2 in human neurons
Drosophila as a Model for MECP2 Gain of Function in Neurons
Methyl-CpG-binding protein 2 (MECP2) is a multi-functional regulator of gene expression. In humans loss of MECP2 function causes classic Rett syndrome, but gain of MECP2 function also causes mental retardation. Although mouse models provide valuable insight into Mecp2 gain and loss of function, the identification of MECP2 genetic targets and interactors remains time intensive and complicated. This study takes a step toward utilizing Drosophila as a model to identify genetic targets and cellular consequences of MECP2 gain-of function mutations in neurons, the principle cell type affected in patients with Rett-related mental retardation. We show that heterologous expression of human MECP2 in Drosophila motoneurons causes distinct defects in dendritic structure and motor behavior, as reported with MECP2 gain of function in humans and mice. Multiple lines of evidence suggest that these defects arise from specific MECP2 function. First, neurons with MECP2-induced dendrite loss show normal membrane currents. Second, dendritic phenotypes require an intact methyl-CpG-binding domain. Third, dendritic defects are amended by reducing the dose of the chromatin remodeling protein, osa, indicating that MECP2 may act via chromatin remodeling in Drosophila. MECP2-induced motoneuron dendritic defects cause specific motor behavior defects that are easy to score in genetic screening. In sum, our data show that some aspects of MECP2 function can be studied in the Drosophila model, thus expanding the repertoire of genetic reagents that can be used to unravel specific neural functions of MECP2. However, additional genes and signaling pathways identified through such approaches in Drosophila will require careful validation in the mouse model
Predicting Benefit From Immune Checkpoint Inhibitors in Patients With Non-Small-Cell Lung Cancer by CT-Based Ensemble Deep Learning: A Retrospective Study
BACKGROUND: Only around 20-30% of patients with non-small-cell lung cancer (NCSLC) have durable benefit from immune-checkpoint inhibitors. Although tissue-based biomarkers (eg, PD-L1) are limited by suboptimal performance, tissue availability, and tumour heterogeneity, radiographic images might holistically capture the underlying cancer biology. We aimed to investigate the application of deep learning on chest CT scans to derive an imaging signature of response to immune checkpoint inhibitors and evaluate its added value in the clinical context.
METHODS: In this retrospective modelling study, 976 patients with metastatic, EGFR/ALK negative NSCLC treated with immune checkpoint inhibitors at MD Anderson and Stanford were enrolled from Jan 1, 2014, to Feb 29, 2020. We built and tested an ensemble deep learning model on pretreatment CTs (Deep-CT) to predict overall survival and progression-free survival after treatment with immune checkpoint inhibitors. We also evaluated the added predictive value of the Deep-CT model in the context of existing clinicopathological and radiological metrics.
FINDINGS: Our Deep-CT model demonstrated robust stratification of patient survival of the MD Anderson testing set, which was validated in the external Stanford set. The performance of the Deep-CT model remained significant on subgroup analyses stratified by PD-L1, histology, age, sex, and race. In univariate analysis, Deep-CT outperformed the conventional risk factors, including histology, smoking status, and PD-L1 expression, and remained an independent predictor after multivariate adjustment. Integrating the Deep-CT model with conventional risk factors demonstrated significantly improved prediction performance, with overall survival C-index increases from 0·70 (clinical model) to 0·75 (composite model) during testing. On the other hand, the deep learning risk scores correlated with some radiomics features, but radiomics alone could not reach the performance level of deep learning, indicating that the deep learning model effectively captured additional imaging patterns beyond known radiomics features.
INTERPRETATION: This proof-of-concept study shows that automated profiling of radiographic scans through deep learning can provide orthogonal information independent of existing clinicopathological biomarkers, bringing the goal of precision immunotherapy for patients with NSCLC closer
Diversity analysis of cotton (Gossypium hirsutum L.) germplasm using the CottonSNP63K Array
Cotton germplasm resources contain beneficial alleles that can be exploited to develop germplasm adapted to emerging environmental and climate conditions. Accessions and lines have traditionally been characterized based on phenotypes, but phenotypic profiles are limited by the cost, time, and space required to make visual observations and measurements. With advances in molecular genetic methods, genotypic profiles are increasingly able to identify differences among accessions due to the larger number of genetic markers that can be measured. A combination of both methods would greatly enhance our ability to characterize germplasm resources. Recent efforts have culminated in the identification of sufficient SNP markers to establish high-throughput genotyping systems, such as the CottonSNP63K array, which enables a researcher to efficiently analyze large numbers of SNP markers and obtain highly repeatable results. In the current investigation, we have utilized the SNP array for analyzing genetic diversity primarily among cotton cultivars, making comparisons to SSR-based phylogenetic analyses, and identifying loci associated with seed nutritional traits. (Résumé d'auteur
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