Ten years of different crop rotations in a no-tillage system – what happened to plant diseases and nematode pests?

Aim To study the long-term effects of crop rotation and residue level on diseases and nematodes in Western Australian no-tillage systems

Vaping Associated Lung Injury Requiring Bilateral Lung Transplant in an Adolescent

Purpose: E-cigarette, or vaping, product use associated lung injury (EVALI) is a newly recognized entity that is being reported with increasing frequency in the literature and mainstream press. The aim of this case report is to radiographically illustrate the fairly rapid progression of a severe case of EVALI that ultimately required a successful bilateral lung transplant, and to describe a unique histopathology correlation. Case Report: Our patient is a 16-year-old, previously healthy male with a two year history of vaping who presented to an outside hospital for dyspnea and nonproductive cough. He was initially treated with antibiotics for community acquired pneumonia. Initial contrast-enhanced CT of the chest demonstrated subtle bilateral but right lower lobe predominant centrilobular nodules, ground glass opacities (GGO) and mild septal thickening. Bronchial alveolar lavage, microbiology studies and autoimmune panel were negative for an infectious or autoimmune etiology. Repeat chest CT only five days later following clinical deterioration demonstrated a dramatic worsening of bilateral nodular airspace opacities, septal thickening, GGO and dependent diffuse consolidations. Pneumomediastinum and mild bronchiectasis were also present. Our patient’s condition continued to decline requiring intubation and subsequent ECMO support. He was transferred to our tertiary care center for bilateral lung transplant. Histopathology of the explanted lungs described predominant acute necrotizing and granulomatous bronchopneumonia with areas of organizing pneumonia. Discussion: The Centers for Disease Control and Prevention currently considers EVALI a diagnosis of exclusion with a confirmed case requiring the use of an e-cigarette 90 days before symptom onset, pulmonary infiltrates on chest imaging, absence of pulmonary infection and no other plausible diagnoses. Various imaging patterns of EVALI have been reported including hypersensitivity pneumonitis, diffuse alveolar hemorrhage, acute eosinophilic pneumonia and lipoid pneumonia, among others. This case demonstrates progression of a severe case of EVALI requiring bilateral lung transplant in an adolescent. Acute necrotizing and granulomatous bronchopneumonia were the predominant histologic features in our patient and have not previously been described in association with EVALI. It is important to consider EVALI in adolescents with a history of e-cigarette use who have a negative infectious and autoimmune work up presenting with severe respiratory symptoms and patterns of lung injury on chest imaging. As the popularity of these inhalational products evolves, radiologists must be informed of the emerging radiographic appearances of EVALI.https://scholarlycommons.henryford.com/merf2020caserpt/1101/thumbnail.jp

Executive Pay and Performance:The Moderating Effect of CEO Power and Governance Structure

This paper examines the crucial question of whether chief executive officer (CEO) power and corporate governance (CG) structure can moderate the pay-for-performance sensitivity (PPS) using a large up-to-date South African dataset. Our findings are three-fold. First, when direct links between executive pay and performance are examined, we find a positive, but relatively small PPS. Second, our results show that in a context of concentrated ownership and weak board structures; the second-tier agency conflict (director monitoring power and opportunism) is stronger than the first-tier agency problem (CEO power and self-interest). Third, additional analysis suggests that CEO power and CG structure have a moderating effect on the PPS. Specifically, we find that the PPS is higher in firms with more reputable, founding and shareholding CEOs, higher ownership by directors and institutions, and independent nomination and remuneration committees, but lower in firms with larger boards, more powerful, and long-tenured CEOs. Overall, our evidence sheds new important theoretical and empirical insights on explaining the PPS with specific focus on the predictions of the optimal contracting and managerial power hypotheses. The findings are generally robust across a raft of econometric models that control for different types of endogeneities, pay, and performance proxies

Conformational activation of ADAMTS13

A disintegrin and metalloprotease with thrombospondin motifs 13 (ADAMTS13) is a metalloprotease that regulates von Willebrand factor (VWF) function. ADAMTS13-mediated proteolysis is determined by conformational changes in VWF, but also may depend on its own conformational activation. Kinetic analysis of WT ADAMTS13 revealed ∼2.5-fold reduced activity compared with ADAMTS13 lacking its C-terminal tail (MDTCS) or its CUB1-2 domains (WTΔCUB1-2), suggesting that the CUB domains naturally limit ADAMTS13 function. Consistent with this suggestion, WT ADAMTS13 activity was enhanced ∼2.5-fold by preincubation with either an anti-CUB mAb (20E9) or VWF D4CK (the natural binding partner for the CUB domains). Furthermore, the isolated CUB1-2 domains not only bound MDTCS, but also inhibited activity by up to 2.5-fold. Interestingly, a gain-of-function (GoF) ADAMTS13 spacer domain variant (R568K/F592Y/R660K/Y661F/Y665F) was ∼2.5-fold more active than WT ADAMTS13, but could not be further activated by 20E9 mAb or VWF D4CK and was unable to bind or to be inhibited by the CUB1-2 domains, suggesting that the inhibitory effects of the CUB domains involve an interaction with the spacer domain that is disrupted in GoF ADAMTS13. Electron microscopy demonstrated a “closed” conformation of WT ADAMTS13 and suggested a more “open” conformation for GoF ADAMTS13. The cryptic spacer domain epitope revealed by conformational unfolding also represents the core antigenic target for autoantibodies in thrombotic thrombocytopenic purpura. We propose that ADAMTS13 circulates in a closed conformation, which is maintained by a CUB–spacer domain binding interaction. ADAMTS13 becomes conformationally activated on demand through interaction of its C-terminal CUB domains with VWF, making it susceptible to immune recognition

Recurrence of Clostridium difficile infection in the Western Australian population

Clostridium difficile, the most common cause of hospital-associated diarrhoea in developed countries, presents major public health challenges. The high clinical and economic burden from C. difficile infection (CDI) relates to the high frequency of recurrent infections caused by either the same or different strains of C. difficile. An interval of 8 weeks after index infection is commonly used to classify recurrent CDI episodes. We assessed strains of C. difficile in a sample of patients with recurrent CDI in Western Australia from October 2011 to July 2017. The performance of different intervals between initial and subsequent episodes of CDI was investigated. Of 4612 patients with CDI, 1471 (32%) were identified with recurrence. PCR ribotyping data were available for initial and recurrent episodes for 551 patients. Relapse (recurrence with same ribotype (RT) as index episode) was found in 350 (64%) patients and reinfection (recurrence with new RT) in 201 (36%) patients. Our analysis indicates that 8- and 20-week intervals failed to adequately distinguish reinfection from relapse. In addition, living in a non-metropolitan area modified the effect of age on the risk of relapse. Where molecular epidemiological data are not available, we suggest that applying an 8-week interval to define recurrent CDI requires more consideration

Properties of the a1 Meson from Lattice QCD

We determine the mass and decay constant of the $a_1$ meson using Monte Carlo simulation of lattice QCD. We find $M_{a_1} = 1250 \pm 80$ MeV and $f_{a_1} = 0.30 \pm 0.03 ~({\rm GeV})^2$, in good agreement with experiment.Comment: 9 page uu-encoded compressed postscript file. version appearing in Phys. Rev. Lett. 74 (1995) 459