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Search for Excited or Exotic Electron Production Using the Dielectron + Photon Signature at CDF in Run II
No full textThe author presents a search for excited or exotic electrons decaying to an electron and a photon with high transverse momentum. An oppositely charged electron is produced in association with the excited electron, yielding a final state dielectron + photon signature. The discovery of excited electrons would be a first indication of lepton compositeness. They use {approx} 202 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV with the Collider Detector at Fermilab during March 2001 through September 2003. The data are consistent with standard model expectations. Upper limits are set on the experimental cross-section {sigma}({bar p}p {yields} ee* {yields} ee{gamma}) at the 95% confidence level in a contact-interaction model and a gauge-mediated interaction model. Limits are also presented as exclusion regions in the parameter space of the excited electron mass (M{sub e*}) and the compositeness energy scale ({Lambda}). In the contact-interaction model, for which there are no previously published limits, they find M{sub e*} < 906 GeV is excluded for M{sub e*} = {Lambda}. In the gauge-mediated model, the exclusion region in the M{sub e*} versus the phenomenological coupling f/{Lambda} parameter space is extended to M{sub e*} < 430 GeV for f/{Lambda} {approx} 10{sup -2} GeV{sup -1}. In comparison, other experiments have excluded M{sub e*} < 280 GeV for f/{Lambda} {approx} 10{sup -2} GeV{sup -1}
Rapid Movement of ‘Candidatus Liberibacter asiaticus’ on ‘Hamlin’ Sweet Orange and ‘Swingle’ Citrumelo Trunks
No full textHuanglongbing (HLB), caused by phloem-limited ‘Candidatus Liberibacter asiaticus’ (CLas), is the primary limiting factor of production in most citrus regions of the world. After infection, CLas is transported systemically throughout the phloem tissues following the source-sink movement. Split-root rhizoboxes and one-sided graft inoculation above the split trunk was used to understand if the vertical distance of the inoculum source and different anatomical structures (grafted or seedling trees) can affect the speed of the CLas movement, as well as the effects of the seasonality on these movements. The time for CLas to reach the roots was not affected by either distance of the inoculum source or tree type. The seasonal infection period appears to have an important effect on CLas movement. Trees inoculated in the summer had fast and uniform movement (first detection at 4 weeks after inoculation). Plants inoculated in the winter had a slow and uneven movement (first CLas detection at 14 weeks after inoculation). Our results indicate that summer and spring are the seasons of CLas down and lateral movement, but this is independent of the vertical distance of the inoculum source or anatomical structures of the plants. The findings from this study aid in the management of HLB in the field, as well as improve the methods for CLas detection. [Figure: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY 4.0 International license
Exogenous Nicotinamide Adenine Dinucleotide Induces Resistance to Citrus Canker in Citrus
No full textNicotinamide adenine dinucleotide (NAD) is a universal electron carrier that participates in important intracellular metabolic reactions and signaling events. Interestingly, emerging evidence in animals indicates that cellular NAD can be actively or passively released into the extracellular space, where it is processed or perceived by ectoenzymes or cell-surface receptors. We have recently shown in Arabidopsis thaliana that exogenous NAD induces defense responses, that pathogen infection leads to release of NAD into the extracellular space at concentrations sufficient for defense activation, and that depletion of extracellular NAD (eNAD) by transgenic expression of the human NAD-hydrolyzing ectoenzyme CD38 inhibits plant immunity. We therefore hypothesize that, during plant–microbe interactions, NAD is released from dead or dying cells into the extracellular space where it interacts with adjacent naïve cells’ surface receptors, which in turn activate downstream immune signaling. However, it is currently unknown whether eNAD signaling is unique to Arabidopsis or the Brassicaceae family. In this study, we treated citrus plants with exogenous NAD+ and tested NAD+-induced transcriptional changes and disease resistance. Our results show that NAD+ induces profound transcriptome changes and strong resistance to citrus canker, a serious citrus disease caused by the bacterial pathogen Xanthomonas citri subsp. citri (Xcc). Furthermore, NAD+-induced resistance persists in new flushes emerging after removal of the tissues previously treated with NAD+. Finally, NAD+ treatment primes citrus tissues, resulting in a faster and stronger induction of multiple salicylic acid pathway genes upon subsequent Xcc infection. Taken together, these results indicate that exogenous NAD+ is able to induce immune responses in citrus and suggest that eNAD may also be an elicitor in this woody plant species
Table_2_Exogenous Nicotinamide Adenine Dinucleotide Induces Resistance to Citrus Canker in Citrus.DOCX
No full textNicotinamide adenine dinucleotide (NAD) is a universal electron carrier that participates in important intracellular metabolic reactions and signaling events. Interestingly, emerging evidence in animals indicates that cellular NAD can be actively or passively released into the extracellular space, where it is processed or perceived by ectoenzymes or cell-surface receptors. We have recently shown in Arabidopsis thaliana that exogenous NAD induces defense responses, that pathogen infection leads to release of NAD into the extracellular space at concentrations sufficient for defense activation, and that depletion of extracellular NAD (eNAD) by transgenic expression of the human NAD-hydrolyzing ectoenzyme CD38 inhibits plant immunity. We therefore hypothesize that, during plant–microbe interactions, NAD is released from dead or dying cells into the extracellular space where it interacts with adjacent naïve cells’ surface receptors, which in turn activate downstream immune signaling. However, it is currently unknown whether eNAD signaling is unique to Arabidopsis or the Brassicaceae family. In this study, we treated citrus plants with exogenous NAD+ and tested NAD+-induced transcriptional changes and disease resistance. Our results show that NAD+ induces profound transcriptome changes and strong resistance to citrus canker, a serious citrus disease caused by the bacterial pathogen Xanthomonas citri subsp. citri (Xcc). Furthermore, NAD+-induced resistance persists in new flushes emerging after removal of the tissues previously treated with NAD+. Finally, NAD+ treatment primes citrus tissues, resulting in a faster and stronger induction of multiple salicylic acid pathway genes upon subsequent Xcc infection. Taken together, these results indicate that exogenous NAD+ is able to induce immune responses in citrus and suggest that eNAD may also be an elicitor in this woody plant species.</p
Table_1_Exogenous Nicotinamide Adenine Dinucleotide Induces Resistance to Citrus Canker in Citrus.XLSX
No full textNicotinamide adenine dinucleotide (NAD) is a universal electron carrier that participates in important intracellular metabolic reactions and signaling events. Interestingly, emerging evidence in animals indicates that cellular NAD can be actively or passively released into the extracellular space, where it is processed or perceived by ectoenzymes or cell-surface receptors. We have recently shown in Arabidopsis thaliana that exogenous NAD induces defense responses, that pathogen infection leads to release of NAD into the extracellular space at concentrations sufficient for defense activation, and that depletion of extracellular NAD (eNAD) by transgenic expression of the human NAD-hydrolyzing ectoenzyme CD38 inhibits plant immunity. We therefore hypothesize that, during plant–microbe interactions, NAD is released from dead or dying cells into the extracellular space where it interacts with adjacent naïve cells’ surface receptors, which in turn activate downstream immune signaling. However, it is currently unknown whether eNAD signaling is unique to Arabidopsis or the Brassicaceae family. In this study, we treated citrus plants with exogenous NAD+ and tested NAD+-induced transcriptional changes and disease resistance. Our results show that NAD+ induces profound transcriptome changes and strong resistance to citrus canker, a serious citrus disease caused by the bacterial pathogen Xanthomonas citri subsp. citri (Xcc). Furthermore, NAD+-induced resistance persists in new flushes emerging after removal of the tissues previously treated with NAD+. Finally, NAD+ treatment primes citrus tissues, resulting in a faster and stronger induction of multiple salicylic acid pathway genes upon subsequent Xcc infection. Taken together, these results indicate that exogenous NAD+ is able to induce immune responses in citrus and suggest that eNAD may also be an elicitor in this woody plant species.</p
Improved determination of the sample composition of dimuon events produced in p(p)over-bar collisions at root s=1.96 TeV
No full textWe use a new method to estimate with 5% accuracy the contribution of pion and kaon in-flight-decays to the dimuon data set acquired with the CDF detector. Based on this improved estimate, we show that the total number and the properties of the collected dimuon events are not yet accounted for by ordinary sources of dimuons which also include the contributions, as measured in the data, of heavy flavor, Υ{hooked}, and Drell-Yan production in addition to muons mimicked by hadronic punchthrough. The number of unaccounted events corresponds to (12.8±3.2)% of the bb̄ production. We find that (23±6)% of the unaccounted events contain additional muon candidates. For comparison, this fraction is (6.9±0.4)% for events due to bb̄ production. © 2011 The Author(s)
Control of Citrus Canker in Greenhouse and Field with a Zinc, Urea, and Peroxide Ternary Solution
No full textAccumulation
of toxic copper in soil and development of copper-resistant
pests are emerging challenges currently faced by the agricultural
community worldwide. As an alternative, we have developed a ternary
zinc chelate solution (TSOL) pesticide where zinc ions are the primary
active ingredient. The material is composed of zinc, urea, and hydrogen
peroxide. Urea was chosen as it is widely used as a plant fertilizer
and can also bind to both zinc and hydrogen peroxide. No phytotoxicity
was observed with TSOL on Meyer lemon (Citrus ×
meyeri) seedlings at a field spray rate of 800 μg/mL
Zn metal concentration. Antimicrobial studies showed that TSOL exhibited
improved killing efficacy against Escherichia coli and Xanthomonas alfalfae compared
to Zn ions alone. Citrus canker field trials in a grapefruit (Chrysopelea paradisi) grove over three years showed
that TSOL provided comparable disease protection to copper products
at an equivalent or lower metal content
Control of Citrus Canker in Greenhouse and Field with a Zinc, Urea, and Peroxide Ternary Solution
No full textAccumulation
of toxic copper in soil and development of copper-resistant
pests are emerging challenges currently faced by the agricultural
community worldwide. As an alternative, we have developed a ternary
zinc chelate solution (TSOL) pesticide where zinc ions are the primary
active ingredient. The material is composed of zinc, urea, and hydrogen
peroxide. Urea was chosen as it is widely used as a plant fertilizer
and can also bind to both zinc and hydrogen peroxide. No phytotoxicity
was observed with TSOL on Meyer lemon (Citrus ×
meyeri) seedlings at a field spray rate of 800 μg/mL
Zn metal concentration. Antimicrobial studies showed that TSOL exhibited
improved killing efficacy against Escherichia coli and Xanthomonas alfalfae compared
to Zn ions alone. Citrus canker field trials in a grapefruit (Chrysopelea paradisi) grove over three years showed
that TSOL provided comparable disease protection to copper products
at an equivalent or lower metal content
Improved determination of the sample composition of dimuon events produced in pp̄ collisions at √s=1.96 TeV
No full textWe use a new method to estimate with 5% accuracy the contribution of pion and kaon in-flight-decays to the dimuon data set acquired with the CDF detector. Based on this improved estimate, we show that the total number and the properties of the collected dimuon events are not yet accounted for by ordinary sources of dimuons which also include the contributions, as measured in the data, of heavy flavor, Υ{hooked}, and Drell-Yan production in addition to muons mimicked by hadronic punchthrough. The number of unaccounted events corresponds to (12.8±3.2)% of the bb̄ production. We find that (23±6)% of the unaccounted events contain additional muon candidates. For comparison, this fraction is (6.9±0.4)% for events due to bb̄ production. © 2011 The Author(s)
Control of Citrus Canker in Greenhouse and Field with a Zinc, Urea, and Peroxide Ternary Solution
No full textAccumulation
of toxic copper in soil and development of copper-resistant
pests are emerging challenges currently faced by the agricultural
community worldwide. As an alternative, we have developed a ternary
zinc chelate solution (TSOL) pesticide where zinc ions are the primary
active ingredient. The material is composed of zinc, urea, and hydrogen
peroxide. Urea was chosen as it is widely used as a plant fertilizer
and can also bind to both zinc and hydrogen peroxide. No phytotoxicity
was observed with TSOL on Meyer lemon (Citrus ×
meyeri) seedlings at a field spray rate of 800 μg/mL
Zn metal concentration. Antimicrobial studies showed that TSOL exhibited
improved killing efficacy against Escherichia coli and Xanthomonas alfalfae compared
to Zn ions alone. Citrus canker field trials in a grapefruit (Chrysopelea paradisi) grove over three years showed
that TSOL provided comparable disease protection to copper products
at an equivalent or lower metal content
