Studies on plasma treatment and priming of seeds of bell pepper (Capsicum annuum L.)

The present investigation was carried out at Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni, Solan during the year 2014 -2015 to study the “Effect of cold plasma treatment and priming on bell pepper (Capsicum annuum L. cultivar California Wonder) for seed germination and seedling vigour. The seeds were ex-posed to various durations of oxygen plasma treatment using glow discharge technique at FCIPT, Institute for Plas-ma Research, Gandhinagar, Gujarat, India. Seeds were pre-treated with power of 100 W for treatment durations of 0, 3, 6, 9, 12, 15 minutes for 0, 4, 8 and 12 month durations. The changes in surface morphology of plasma treated seeds were studied by Scanning Electron Microscopy (SEM) and Contact Angle Goniometer. Along with plasma treatment, seeds were also treated with standard priming method i.e osmoprimng for comparison. Results showed that plasma treatment alone as well as in combination with osmoprimng up to 6 minutes duration had positive effects on seed germination and seedling vigour. Germination and vigour indices significantly increased by 21.75% and 90.71% respectively. Characteristics of germination percentage, speed of germination, seedling vigour index-I & II, significantly increased by 13.92%, 1.39 cm, 0.38 mg, 322.07 respectively, compared with control. And it was found that immediately after plasma exposure the germination (84.41%) and vigour (228.50) was highest and it was reduced to (73.54%) and (174.27) after 12 months of storage. These results indicated that cold plasma treatment might promote the growth and modify the speed of germination i.e. higher speed of germination was observed in seeds exposed to plasma treat-ment for 6 minutes (59.82%), whereas, lowest germination speed (40.76%) was observed in untreated control

Plasticity of rosette size in response to nitrogen availability is controlled by an RCC1-family protein

Nitrogen (N) is fundamental to plant growth, development and yield. Genes underlying N utilization and assimilation are well-characterized, but mechanisms underpinning plasticity of different phenotypes in response to N remain elusive. Here, using Arabidopsis thaliana accessions, we dissected the genetic architecture of plasticity in early and late rosette diameter, flowering time and yield, in response to three levels of N in the soil. Furthermore, we found that the plasticity in levels of primary metabolites were related with the plasticities of the studied traits. Genome-wide association analysis identified three significant associations for phenotypic plasticity, one for early rosette diameter and two for flowering time. We confirmed that the gene At1g19880, hereafter named as PLASTICITY OF ROSETTE TO NITROGEN 1 (PROTON1), encoding for a regulator of chromatin condensation 1 (RCC1) family protein, conferred plasticity of rosette diameter in response to N. Treatment of PROTON1 T-DNA line with salt implied that the reduced plasticity of early rosette diameter was not a general growth response to stress. We further showed that plasticities of growth and flowering-related traits differed between environmental cues, indicating decoupled genetic programs regulating these traits. Our findings provide a prospective to identify genes that stabilize performance under fluctuating environments.Peer reviewe

Survey of Cochlear Implant User Satisfaction with the Neptune™ Waterproof Sound Processor

A multi-center self-assessment survey was conducted to evaluate patient satisfaction with the Advanced Bionics Neptune™ waterproof sound processor used with the AquaMic™ totally submersible microphone. Subjective satisfaction with the different Neptune™ wearing options, comfort, ease of use, sound quality and use of the processor in a range of active and water related situations were assessed for 23 adults and 73 children, using an online and paper based questionnaire. Upgraded subjects compared their previous processor to the Neptune™. The Neptune™ was most popular for use in general sports and in the pool. Subjects were satisfied with the sound quality of the sound processor outside and under water and following submersion. Seventy-eight percent of subjects rated waterproofness as being very useful and 83% of the newly implanted subjects selected waterproofness as one of the reasons why they chose the Neptune™ processor. Providing a waterproof sound processor is considered by cochlear implant recipients to be useful and important and is a factor in their processor choice. Subjects reported that they were satisfied with the Neptune™ sound quality, ease of use and different wearing options

An inhomogeneous universe with thick shells and without cosmological constant

We build an exact inhomogeneous universe composed of a central flat Friedmann zone up to a small redshift $z_1$, a thick shell made of anisotropic matter, an hyperbolic Friedmann metric up to the scale where dimming galaxies are observed ($z\simeq 1.7$) that can be matched to a hyperbolic Lema\^{i}tre-Tolman-Bondi spacetime to best fit the WMAP data at early epochs. We construct a general framework which permits us to consider a non-uniform clock rate for the universe. As a result, both for a uniform time and a uniform Hubble flow, the deceleration parameter extrapolated by the central observer is always positive. Nevertheless, by taking a non-uniform Hubble flow, it is possible to obtain a negative central deceleration parameter, that, with certain parameter choices, can be made the one observed currently. Finally, it is conjectured a possible physical mechanism to justify a non-uniform time flow.Comment: Version published in Class. Quantum gra

Divergence and overlap in bilingual concept representations

A research study of conceptual representation in bilinguals.Chinese-English bilingual participants listed exemplars of 10 common categories on two occasions, one week apart. Half responded in the same language in both sessions (Chinese or English) and half responded in one language in one session and the other language in the other session. There was substantial overlap in the exemplars listed across the sessions, but those responding in different languages showed less overlap than those responding in the same language. The results indicate differences in graded structure of the categories across the participants’ languages; the exemplars associated with translation equivalent category labels in bilinguals’ two languages differ in how representative they are of the category

"Swiss-Cheese" Inhomogeneous Cosmology & the Dark Energy Problem

We study an exact swiss-cheese model of the Universe, where inhomogeneous LTB patches are embedded in a flat FLRW background, in order to see how observations of distant sources are affected. We find negligible integrated effect, suppressed by (L/R_{H})^3 (where L is the size of one patch, and R_{H} is the Hubble radius), both perturbatively and non-perturbatively. We disentangle this effect from the Doppler term (which is much larger and has been used recently \cite{BMN} to try to fit the SN curve without dark energy) by making contact with cosmological perturbation theory.Comment: 35 pages, 6 figure

Local Void vs Dark Energy: Confrontation with WMAP and Type Ia Supernovae

It is now a known fact that if we happen to be living in the middle of a large underdense region, then we will observe an "apparent acceleration", even when any form of dark energy is absent. In this paper, we present a "Minimal Void" scenario, i.e. a "void" with minimal underdensity contrast (of about -0.4) and radius (~ 200-250 Mpc/h) that can, not only explain the supernovae data, but also be consistent with the 3-yr WMAP data. We also discuss consistency of our model with various other measurements such as Big Bang Nucleosynthesis, Baryon Acoustic Oscillations and local measurements of the Hubble parameter, and also point out possible observable signatures.Comment: Minor numerical errors and typos corrected, references adde

LTB solutions in Newtonian gauge: from strong to weak fields

Lemaitre-Tolman-Bondi (LTB) solutions are used frequently to describe the collapse or expansion of spherically symmetric inhomogeneous mass distributions in the Universe. These exact solutions are obtained in the synchronous gauge where nonlinear dynamics (with respect to the FLRW background) induce large deviations from the FLRW metric. In this paper we show explicitly that this is a gauge artefact (for realistic sub-horizon inhomogeneities). We write down the nonlinear gauge transformation from synchronous to Newtonian gauge for a general LTB solution using the fact that the peculiar velocities are small. In the latter gauge we recover the solution in the form of a weakly perturbed FLRW metric that is assumed in standard cosmology. Furthermore we show how to obtain the LTB solutions directly in Newtonian gauge and illustrate how the Newtonian approximation remains valid in the nonlinear regime where cosmological perturbation theory breaks down. Finally we discuss the implications of our results for the backreaction scenario.Comment: 17 page

False-negative RT-PCR for COVID-19 and a diagnostic risk score: a retrospective cohort study among patients admitted to hospital

OBJECTIVE: To describe the characteristics and outcomes of patients with a clinical diagnosis of COVID-19 and false-negative SARS-CoV-2 reverse transcription-PCR (RT-PCR), and develop and internally validate a diagnostic risk score to predict risk of COVID-19 (including RT-PCR-negative COVID-19) among medical admissions. DESIGN: Retrospective cohort study. SETTING: Two hospitals within an acute NHS Trust in London, UK. PARTICIPANTS: All patients admitted to medical wards between 2 March and 3 May 2020. OUTCOMES: Main outcomes were diagnosis of COVID-19, SARS-CoV-2 RT-PCR results, sensitivity of SARS-CoV-2 RT-PCR and mortality during hospital admission. For the diagnostic risk score, we report discrimination, calibration and diagnostic accuracy of the model and simplified risk score and internal validation. RESULTS: 4008 patients were admitted between 2 March and 3 May 2020. 1792 patients (44.8%) were diagnosed with COVID-19, of whom 1391 were SARS-CoV-2 RT-PCR positive and 283 had only negative RT-PCRs. Compared with a clinical reference standard, sensitivity of RT-PCR in hospital patients was 83.1% (95% CI 81.2%-84.8%). Broadly, patients with false-negative RT-PCR COVID-19 and those confirmed by positive PCR had similar demographic and clinical characteristics but lower risk of intensive care unit admission and lower in-hospital mortality (adjusted OR 0.41, 95% CI 0.27-0.61). A simple diagnostic risk score comprising of age, sex, ethnicity, cough, fever or shortness of breath, National Early Warning Score 2, C reactive protein and chest radiograph appearance had moderate discrimination (area under the receiver-operator curve 0.83, 95% CI 0.82 to 0.85), good calibration and was internally validated. CONCLUSION: RT-PCR-negative COVID-19 is common and is associated with lower mortality despite similar presentation. Diagnostic risk scores could potentially help triage patients requiring admission but need external validation