1,314 research outputs found
The Effects of Priming Eruca sativa Seeds with Short-Chain AHL C6-HSL at Bard Farm
Many gram-negative bacteria use quorum sensing to assess population densities and cooperate with another. The quorum sensing autoinducers N-acyl homoserine lactones (AHLs) have been found to cause altered gene expression patterns in plants, resulting in increased root and shoot growth as well as induced pathogenic resistance in various species. Researchers have begun exploring the ways AHLs may be used in agricultural systems to reduce the use of environmentally harmful synthetic fertilizers and pesticides. In this study, the effect of priming arugula (Eruca sativa) seeds with the short-chain AHL C6-HSL was investigated at Bard Farm in Annandale-On-Hudson, New York. Leaf lengths of AHL-primed, water-primed and control plants were compared to investigate the effect of AHL seed priming on arugula growth. The study sought to also analyze the effects C6-HSL may have on the bacterial diversity and dominant functional groups present in root and root soil samples collected from the plants, though metagenomic analysis ultimately could not be performed due to COVID-19 related delays in DNA sequencing. Soil moisture and temperature was measured three times over the course of the experiment to contextualize results. Soil samples of the experiential plot were also collected before and after the in-field portion of the experiment for metagenomic analysis. The study ultimately found C6-HLS seed priming to have no significant effect on leaf length (P=1.57). Metagenomic analysis will be performed once the sequenced samples are available
Fees for Extracurricular Activities Alienate Students Who Would Otherwise Participate and Should Be Replaced with Alternate Means of Fundraising
The Relative Contributions of Experiential Avoidance and Distress Tolerance to OC Symptoms
Background: Obsessive beliefs account for substantial (but not all) obsessive-compulsive (OC) symptoms. Intolerance of internal experiences (IIE), which encompasses the constructs of experiential avoidance (EA) and distress tolerance (DT), refers to difficulty managing unwanted thoughts, emotions, and other internal states, and might add to current explanatory models. Although IIE appears to be conceptually relevant to obsessive-compulsive (OC) symptoms, scant research has examined this relationship empirically. Aim: The present study examined the relative contributions of EA and DT as predictors of OC symptom dimensions. Method: A nonclinical sample ( n = 496) completed self-report questionnaires measuring general distress, EA, DT and OC symptom dimensions. Results: All variables of interest were significantly (all p s ≤ .001) correlated with one another, such that higher general distress, higher EA, and lower DT were associated with greater OC symptom severity for all symptom dimensions; however, only EA independently predicted obsessional symptoms, but not other OC symptom dimensions. Conclusions: One's willingness to endure (i.e. EA), rather than their ability to tolerate (i.e. DT) unpleasant internal experiences best predicts obsessional symptoms (i.e. obsessing) above and beyond general distress. Potential implications for understanding, assessing, and treating OC symptoms are discussed
Patients' Perceptions and Experiences of Shared Decision-Making in Primary HIV Care Clinics
Shared decision-making (SDM) is considered best practice in health care. Prior studies have explored attitudes and barriers/facilitators to SDM, with few specific to HIV care. We interviewed 53 patients in HIV primary care clinics in California to understand the factors and situations that may promote or hinder engagement in SDM. Studies in other populations have found that patients' knowledge about their diseases and their trust in providers facilitated SDM. We found these features to be more nuanced for HIV. Perceptions of personal agency, knowledge about one's disease, and trust in provider were factors that could work for or against SDM. Overall, we found that participants described few experiences of SDM, especially among those with no comorbidities. Opportunities for SDM in routine HIV care (e.g., determining antiretroviral therapy) may arise infrequently because of treatment advances. These findings yield considerations for adapting SDM to fit the context of HIV care
Si microwire-array solar cells
Si microwire-array solar cells with Air Mass 1.5 Global conversion efficiencies of up to 7.9% have been fabricated using an active volume of Si equivalent to a 4 μm thick Si wafer. These solar cells exhibited open-circuit voltages of 500 mV, short-circuit current densities (J_(sc)) of up to 24 mA cm^(-2), and fill factors >65% and employed Al_2O_3 dielectric particles that scattered light incident in the space between the wires, a Ag back reflector that prevented the escape of incident illumination from the back surface of the solar cell, and an a-SiN_x:H passivation/anti-reflection layer. Wire-array solar cells without some or all of these design features were also fabricated to demonstrate the importance of the light-trapping elements in achieving a high J_(sc). Scanning photocurrent microscopy images of the microwire-array solar cells revealed that the higher J_(sc) of the most advanced cell design resulted from an increased absorption of light incident in the space between the wires. Spectral response measurements further revealed that solar cells with light-trapping elements exhibited improved red and infrared response, as compared to solar cells without light-trapping elements
High-performance Si microwire photovoltaics
Crystalline Si wires, grown by the vapor–liquid–solid (VLS)
process, have emerged as promising candidate materials for lowcost, thin-film photovoltaics. Here, we demonstrate VLS-grown Si microwires that have suitable electrical properties for high-performance photovoltaic applications, including long minority-carrier diffusion lengths (L_n » 30 µm) and low surface recombination velocities (S « 70 cm·s^(-1)). Single-wire radial p–n junction solar cells were fabricated with amorphous silicon and silicon nitride
surface coatings, achieving up to 9.0% apparent photovoltaic efficiency, and exhibiting up to ~600 mV open-circuit voltage with over 80% fill factor. Projective single-wire measurements and optoelectronic simulations suggest that large-area Si wire-array solar cells have the potential to exceed 17% energy-conversion efficiency, offering a promising route toward cost-effective crystalline Si photovoltaics
Systematic performance of the ASKAP Fast Radio Burst search algorithm
Detecting fast radio bursts (FRBs) requires software pipelines to search for
dispersed single pulses of emission in radio telescope data. In order to enable
an unbiased estimation of the underlying FRB population, it is important to
understand the algorithm efficiency with respect to the search parameter space
and thus the survey completeness. The Fast Real-time Engine for Dedispersing
Amplitudes (FREDDA) search pipeline is a single pulse detection pipeline
designed to identify radio pulses over a large range of dispersion measures
(DM) with low latency. It is used on the Australian Square Kilometre Array
Pathfinder (ASKAP) for the Commensal Real-time ASKAP Fast Transients (CRAFT)
project . We utilise simulated single pulses in the low- and high-frequency
observation bands of ASKAP to analyse the performance of the pipeline and infer
the underlying FRB population. The simulation explores the Signal-to-Noise
Ratio (S/N) recovery as a function of DM and the temporal duration of FRB
pulses in comparison to injected values. The effects of intra-channel
broadening caused by dispersion are also carefully studied in this work using
control datasets. Our results show that for Gaussian-like single pulses, of the injected signal is recovered by pipelines such as FREDDA at DM <
3000 using standard boxcar filters compared to an ideal
incoherent dedispersion match filter. Further calculations with sensitivity
implies at least of FRBs in a Euclidean universe at target
sensitivity will be missed by FREDDA and HEIMDALL, another common pipeline, in
ideal radio environments at 1.1 GHz.Comment: 11 pages 13 figures. Accepted for MNRAS; Data and simulation code
available onlin
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