Sclerotinia sclerotiorum is a pathogenic fungus that infects hundreds of crop species, causing extensive yield loss every year. Chemical fungicides are used to control this phytopathogen, but with ...concerns about increasing resistance and impacts on non-target species, there is a need to develop alternative control measures. In the present study, we engineered Brassica napus to constitutively express a hairpin (hp)RNA molecule to silence ABHYRDOLASE-3 in S. sclerotiorum. We demonstrate the potential for Host Induced Gene Silencing (HIGS) to protect B. napus from S. sclerotiorum using leaf, stem and whole plant infection assays. The interaction between the transgenic host plant and invading pathogen was further characterized at the molecular level using dual-RNA sequencing and at the anatomical level through microscopy to understand the processes and possible mechanisms leading to increased tolerance to this damaging necrotroph. We observed significant shifts in the expression of genes relating to plant defense as well as cellular differences in the form of structural barriers around the site of infection in the HIGS-protected plants. Our results provide proof-of-concept that HIGS is an effective means of limiting damage caused by S. sclerotiorum to the plant and demonstrates the utility of this biotechnology in the development of resistance against fungal pathogens.
Context:
Human granulosa cells (GC) acquire LH receptor (LHR) expression during the follicular phase of the menstrual cycle. Currently, the precise follicular stage is unknown, and specific roles of ...LH in the follicular development are not fully understood.
Objective:
Our objective was to measure LHR gene expression on GC and cumulus cells (CC) from normal human follicles with diameters form 3–20 mm.
Design, Setting, and Patients:
At a university hospital, GC, CC, and the corresponding follicular fluid (FF) were collected from patients undergoing fertility preservation by having one ovary frozen and patients undergoing infertility treatment.
Interventions:
Cells and fluids were isolated from surgically excised ovaries or from aspirated preovulatory follicles.
Main Outcome Measures:
We evaluated gene expression of LHR, FSHR, androgen receptor (AR), aromatase (CYP19a1), and AMHR2 normalized to the GAPDH expression and associated with FF levels of anti-Mullerian hormone, inhibin-B, and steroids.
Results:
LHR expression was maximal in GC from preovulatory follicles before ovulation induction. A majority of 150 antral follicles (3–10 mm in diameter) showed LHR expression at approximately 10% of the maximum, and LHR expression showed significant associations with FSHR, AR, CYP19a1, and AMHR2 and with FF estradiol and progesterone. Levels of FSHR continued to decline in GC as the follicular diameter increased.
Conclusions:
The LHR gene is expressed in GC of human antral follicles throughout the follicular phase and is significantly associated with expression of the CYP19a1 gene and with the corresponding FF concentrations of estradiol and progesterone. LH appears to affect human follicular development during most the follicular phase in normal women.
Perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) are used in a variety of consumer products and have been detected worldwide in human blood. Recent studies mainly of highly exposed ...populations have indicated that PFOA and PFOS may affect serum cholesterol levels, but the magnitude of the effect may be inconsistent across exposure levels. The aim of the present cross-sectional study was to investigate the association between plasma PFOA and PFOS and total cholesterol in a general, middle-aged Danish population. The study population comprised 753 individuals (663 men and 90 women), 50-65 years of age, nested within a Danish cohort of 57,053 participants. Blood samples were taken from all cohort members at enrolment (1993-1997) and stored in a biobank at -150°C. Plasma levels of PFOA and PFOS and serum levels of total cholesterol were measured. The associations between plasma PFOA and PFOS levels and total cholesterol levels were analysed by generalized linear models, both crude and adjusted for potential confounders. We observed statistically significant positive associations between both perfluorinated compounds and total cholesterol, e.g. a 4.4 95% CI = 1.1-7.8 higher concentration of total cholesterol (mg/dL) per interquartile range of PFOA plasma level. Sex and prevalent diabetes appeared to modify the association between PFOA and PFOS, respectively, and cholesterol. In conclusion, this study indicated positive associations between plasma PFOA and PFOS levels and total cholesterol in a middle-aged Danish population, although whether the observed pattern of results reflects a causal association is unclear.
We present an end-to-end computational system for autonomous materials discovery. The system aims for cost-effective optimization in large, high-dimensional search spaces of materials by adopting a ...sequential, agent-based approach to deciding which experiments to carry out. In choosing next experiments, agents can make use of past knowledge, surrogate models, logic, thermodynamic or other physical constructs, heuristic rules, and different exploration-exploitation strategies. We show a series of examples for (i) how the discovery campaigns for finding materials satisfying a relative stability objective can be simulated to design new agents, and (ii) how those agents can be deployed in real discovery campaigns to control experiments run externally, such as the cloud-based density functional theory simulations in this work. In a sample set of 16 campaigns covering a range of binary and ternary chemistries including metal oxides, phosphides, sulfides and alloys, this autonomous platform found 383 new stable or nearly stable materials with no intervention by the researchers.
We present an end-to-end computational system for autonomous materials discovery.
RNA interference (RNAi) technologies have recently been developed to control a growing number of agronomically significant fungal phytopathogens, including the white mold pathogen, Sclerotinia ...sclerotiorum. Exposure of this fungus to exogenous double-stranded RNA (dsRNA) results in potent RNAi-mediated knockdown of target genes' transcripts, but it is unclear how the dsRNA can enter the fungal cells. In nematodes, specialized dsRNA transport proteins such as SID-1 facilitate dsRNA uptake, but for many other eukaryotes in which the dsRNA uptake mechanisms have been examined, endocytosis appears to mediate the uptake process. In this study, using live cell imaging, transgenic fungal cultures and endocytic inhibitors, we determined that the uptake mechanism in S. sclerotiorum occurs through clathrin-mediated endocytosis. RNAi-mediated knockdown of several clathrin-mediated endocytic genes' transcripts confirmed the involvement of this cellular uptake process in facilitating RNAi in this fungus. Understanding the mode of dsRNA entry into the fungus will prove useful in designing and optimizing future dsRNA-based control methods and in anticipating possible mechanisms by which phytopathogens may develop resistance to this novel category of fungicides.
Virus-induced wheezing episodes in infancy often precede the development of asthma. Whether infections with specific viral pathogens confer differential future asthma risk is incompletely understood.
...To define the relationship between specific viral illnesses and early childhood asthma development.
A total of 259 children were followed prospectively from birth to 6 years of age. The etiology and timing of specific viral wheezing respiratory illnesses during early childhood were assessed using nasal lavage, culture, and multiplex reverse transcriptase-polymerase chain reaction. The relationships of these virus-specific wheezing illnesses and other risk factors to the development of asthma were analyzed.
Viral etiologies were identified in 90% of wheezing illnesses. From birth to age 3 years, wheezing with respiratory syncytial virus (RSV) (odds ratio OR, 2.6), rhinovirus (RV) (OR, 9.8), or both RV and RSV (OR , 10) was associated with increased asthma risk at age 6 years. In Year 1, both RV wheezing (OR, 2.8) and aeroallergen sensitization (OR, 3.6) independently increased asthma risk at age 6 years. By age 3 years, wheezing with RV (OR, 25.6) was more strongly associated with asthma at age 6 years than aeroallergen sensitization (OR, 3.4). Nearly 90% (26 of 30) of children who wheezed with RV in Year 3 had asthma at 6 years of age.
Among outpatient viral wheezing illnesses in infancy and early childhood, those caused by RV infections are the most significant predictors of the subsequent development of asthma at age 6 years in a high-risk birth cohort.
While university-based study abroad programs have become a core component of multicultural education, I argue that in many ways the dominant model of study abroad is rooted in a white masculinist ...episteme predicated on anthropological consumption of the "Other" without, and largely opposed to, meaningful examinations of the self. The present study is a critical exploration of a study abroad program created by Black women for students of African descent. Through two conceptual frameworks-Black Atlantic Consciousness and Womanism-I note the ways in which the study abroad program departed sharply from traditional programming found at historically white institutions. Utilizing narrative thematic case study analysis, findings reveal both the program designers' goals and intentions for this study abroad program, as well as the ways those goals translated into pedagogical and curricular praxis. Three subthemes comprise the larger theme related to goals and intentions: self-awareness and communal awareness, African diasporic gendered identity, and deconstruction with student support. Four subthemes organize the theme curricular and pedagogical praxis: spiritually detoxing experiences, Afrocentric role-playing and storytelling/making, integration of counseling and emotional support resources, and institutional subversion. The article concludes with reflections on and implications for culturally relevant study abroad programming.
Abstract
For high-throughput screening of materials for heterogeneous catalysis, scaling relations provides an efficient scheme to estimate the chemisorption energies of hydrogenated species. ...However, conditioning on a single descriptor ignores the model uncertainty and leads to suboptimal prediction of the chemisorption energy. In this article, we extend the single descriptor linear scaling relation to a multi-descriptor linear regression models to leverage the correlation between adsorption energy of any two pair of adsorbates. With a large dataset, we use Bayesian Information Criteria (BIC) as the model evidence to select the best linear regression model. Furthermore, Gaussian Process Regression (GPR) based on the meaningful convolution of physical properties of the metal-adsorbate complex can be used to predict the baseline residual of the selected model. This integrated Bayesian model selection and Gaussian process regression, dubbed as residual learning, can achieve performance comparable to standard DFT error (0.1 eV) for most adsorbate system. For sparse and small datasets, we propose an ad hoc Bayesian Model Averaging (BMA) approach to make a robust prediction. With this Bayesian framework, we significantly reduce the model uncertainty and improve the prediction accuracy. The possibilities of the framework for high-throughput catalytic materials exploration in a realistic setting is illustrated using large and small sets of both dense and sparse simulated dataset generated from a public database of bimetallic alloys available in Catalysis-Hub.org.
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