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Frequency scanning is a unique feature of periodic leaky-wave antennas (P-LWAs), according to which the main beam scans space upon frequency control. However, one-dimensional (1D) and two-dimensional P-LWAs are capable of scanning space only in a single plane, with a fan beam and a pencil beam, respectively. Here, we explore the possibility of achieving full-space frequency-scanning coverage with 2D P-LWA leveraging multiple space harmonics. Furthermore, we propose a design of 2D P-LWAs with series feeding network, which has 4 ports and capable of covering the full-space. Finally, the results are discussed and plotted based on analytical dispersion diagrams and array factor theory.

We explore the application of phase diversity to calibrate the non common path aberrations (NCPA) in the Gemini Planet Imager (GPI). This is first investigated in simulation in order to characterize the ideal technique parameters with simulated GPI calibration source data. The best working simulation parameters are derived and we establish the algorithm's capability to recover an injected astigmatism. Furthermore, the real data appear to exhibit signs of de-centering between the in and out of focus images that are required by phase diversity; this effect can arise when the diverse images are acquired in closed loop and are close to the non-linear regime of the wavefront sensor. We show in simulation that this effect can inhibit our algorithm, which does not take into account the impact of de-centering between images. To mitigate this effect, we validate the technique of using a single diverse image with our algorithm; this is first demonstrated in simulation and then applied to the real GPI data. Following this approach, we find that we can successfully recover a known astigmatism injection using the real GPI data and subsequently apply an NCPA correction to GPI (in the format of offset reference slopes) to improve the relative Strehl ratio by 5%; we note this NCPA correction application is rudimentary and a more thorough application will be investigated in the near future. Finally, the estimated NCPA in the form of astigmatism and coma agree well with the magnitude of the same modes reported by Poyneer et al. 2016.

Limited data exist evaluating the effect of blood pressure (BP) on clinical outcomes among patients with acute ischemic stroke with large vessel occlusion treated with mechanical thrombectomy (MT). We sought to evaluate the association of BP levels on clinical outcomes among patients with acute ischemic stroke with large vessel occlusion treated with MT. Studies were identified that reported the association of systolic BP (SBP) or diastolic BP levels before, during, or after MT on the outcomes of patients with acute ischemic stroke treated with MT. Unadjusted and adjusted analyses of studies reporting odds ratios (OR adj ) per 10 mm Hg BP increment were performed. Our analysis included 25 studies comprising 6474 patients. Higher pre-MT mean SBP ( P =0.008) and post-MT maximum SBP ( P =0.009) levels were observed in patients who died within 3 months. Patients with 3-month functional independence were noted to have lower pre-MT ( P <0.001) and post-MT maximum SBP levels ( P <0.001). In adjusted analyses, increasing post-MT maximum SBP and diastolic BP levels were associated with 3-month mortality (OR adj , 1.19 [95% CI,1.00–1.43]; I 2 =78%, P value for Cochran Q test: 0.001) and symptomatic intracranial hemorrhage (OR adj , 1.65 [95% CI, 1.11–2.44]; I 2 =0%, P value for Cochran Q test: 0.80), respectively. Increasing pre- and post-MT mean SBP levels were associated with lower odds of 3-month functional independence (OR adj , 0.86 [95% CI, 0.77–0.96]; I 2 =18%, P value for Cochran Q test: 0.30) and (OR adj , 0.80 [95% CI, 0.72–0.89]; I 2 =0%, P value for Cochran Q test: 0.51), respectively. In conclusion, elevated BP levels before and after MT are associated with adverse outcomes among patients with acute ischemic stroke with large vessel occlusion.

The kidney sessions of the 2017 Banff Conference focused on 2 areas: clinical implications of inflammation in areas of interstitial fibrosis and tubular atrophy (i‐IFTA) and its relationship to T cell–mediated rejection (TCMR), and the continued evolution of molecular diagnostics, particularly in the diagnosis of antibody‐mediated rejection (ABMR). In confirmation of previous studies, it was independently demonstrated by 2 groups that i‐IFTA is associated with reduced graft survival. Furthermore, these groups presented that i‐IFTA, particularly when involving >25% of sclerotic cortex in association with tubulitis, is often a sequela of acute TCMR in association with underimmunosuppression. The classification was thus revised to include moderate i‐IFTA plus moderate or severe tubulitis as diagnostic of chronic active TCMR. Other studies demonstrated that certain molecular classifiers improve diagnosis of ABMR beyond what is possible with histology, C4d, and detection of donor‐specific antibodies (DSAs) and that both C4d and validated molecular assays can serve as potential alternatives and/or complements to DSAs in the diagnosis of ABMR. The Banff ABMR criteria are thus updated to include these alternatives. Finally, the present report paves the way for the Banff scheme to be part of an integrative approach for defining surrogate endpoints in next‐generation clinical trials. The Banff consortium presents revisions to the diagnostic criteria for T cell– and antibody‐mediated kidney transplant rejection, including specific criteria for chronic active T cell–mediated rejection, plus prospects for integrative endpoints in clinical trials. See related articles on pages 321, 364, and 377.

Long non-coding RNAs (lncRNAs) are a growing focus of cancer genomics studies, creating the need for a resource of lncRNAs with validated cancer roles. Furthermore, it remains debated whether mutated lncRNAs can drive tumorigenesis, and whether such functions could be conserved during evolution. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, we introduce the Cancer LncRNA Census (CLC), a compilation of 122 GENCODE lncRNAs with causal roles in cancer phenotypes. In contrast to existing databases, CLC requires strong functional or genetic evidence. CLC genes are enriched amongst driver genes predicted from somatic mutations, and display characteristic genomic features. Strikingly, CLC genes are enriched for driver mutations from unbiased, genome-wide transposon-mutagenesis screens in mice. We identified 10 tumour-causing mutations in orthologues of 8 lncRNAs, including LINC-PINT and NEAT1, but not MALAT1. Thus CLC represents a dataset of high-confidence cancer lncRNAs. Mutagenesis maps are a novel means for identifying deeply-conserved roles of lncRNAs in tumorigenesis. Communications Biology, 3 (1) ISSN:2399-3642

What are the psychological consequences of the increasingly politicized nature of the COVID-19 pandemic in the United States relative to similar Western countries? In a two-wave study completed early (March) and later (December) in the pandemic, we found that polarization was greater in the United States ( N = 1,339) than in Canada ( N = 644) and the United Kingdom. ( N = 1,283). Political conservatism in the United States was strongly associated with engaging in weaker mitigation behaviors, lower COVID-19 risk perceptions, greater misperceptions, and stronger vaccination hesitancy. Although there was some evidence that cognitive sophistication was associated with increased polarization in the United States in December (but not March), cognitive sophistication was nonetheless consistently negatively correlated with misperceptions and vaccination hesitancy across time, countries, and party lines. Furthermore, COVID-19 skepticism in the United States was strongly correlated with distrust in liberal-leaning mainstream news outlets and trust in conservative-leaning news outlets, suggesting that polarization may be driven by differences in information environments.

ABSTRACTHuman cytomegalovirus (HCMV) infection causes severe illness in newborns and immunocompromised patients. Since treatment options are limited there is an unmet need for new therapeutic approaches. Defensins are cationic peptides, produced by various human tissues, which serve as antimicrobial effectors of the immune system. Furthermore, some defensins are proteolytically cleaved, resulting in the generation of smaller fragments with increased activity. Together, this led us to hypothesize that defensin-derived peptides are natural human inhibitors of virus infection with low toxicity. We screened several human defensin HNP4- and HD5-derived peptides and found HD5(1-9) to be antiviral without toxicity at high concentrations. HD5(1-9) inhibited HCMV cellular attachment and thereby entry and was active against primary as well as a multiresistant HCMV isolate. Moreover, cysteine and arginine residues were identified to mediate the antiviral activity of HD5(1-9). Altogether, defensin-derived peptides, in particular HD5(1-9), qualify as promising candidates for further development as a novel class of HCMV entry inhibitors.AUTHOR SUMMARYDefensins are peptides produced by various human organs which take part in the natural defense against pathogens. Recently, it has been shown that defensins are further cleaved to smaller peptides that have high intrinsic anti-microbial activity. We here challenged the hypothesis that these peptides might have antiviral activity, and due to their presumably natural occurrence, low toxicity. Indeed, we found one peptide fragment that turned out to block the attachment of the human cytomegalovirus (HCMV) to cells. Furthermore, this peptide did not show toxicity in various cellular assays or impede the embryonic development of zebrafish at the concentrations used to block HCMV. This is important, since HCMV is one of the most important viral congenital infections. Altogether, our results hold promise for the development of a new class of antivirals against HCMV.

Background Patient preference is pivotal for widespread adoption of tests in clinical practice. Patient preferences for invasive versus other noninvasive tests for coronary artery disease are not known. Purpose To compare patient acceptance and preferences for noninvasive and invasive cardiac imaging in North and South America, Asia, and Europe. Materials and Methods This was a prospective 16-center trial in 381 study participants undergoing coronary CT angiography with stress perfusion, SPECT, and invasive coronary angiography (ICA). Patient preferences were collected by using a previously validated questionnaire translated into eight languages. Responses were converted to ordinal scales and were modeled with generalized linear mixed models. Results In patients in whom at least one test was associated with pain, CT and SPECT showed reduced median pain levels, reported on 0-100 visual analog scales, from 20 for ICA (interquartile range [IQR], 4-50) to 6 for CT (IQR, 0-27.5) and 5 for SPECT (IQR, 0-25) (P < .001). Patients from Asia reported significantly more pain than patients from other continents for ICA (median, 25; IQR, 10-50; P = .01), CT (median, 10; IQR, 0-30; P = .02), and SPECT (median, 7; IQR, 0-28; P = .03). Satisfaction with preparation differed by continent and test (P = .01), with patients from Asia reporting generally lower ratings. Patients from North America had greater percentages of "very high" or "high" satisfaction than patients from other continents for ICA (96% vs 82%, respectively; P < .001) and SPECT (95% vs 79%, respectively; P = .04) but not for CT (89% vs 86%, respectively; P = .70). Among all patients, CT was preferred by 54% of patients, compared with 18% for SPECT and 28% for ICA (P < .001). Conclusion For cardiac imaging, patients generally favored CT angiography with stress perfusion, while study participants from Asia generally reported lowest satisfaction. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Woodard and Nguyen in this issue.