Antibacterial activity of mexican oregano essential oil (Lippia berlandieri) against the phytopathogenic bacterium Xanthomonas euvesicatoria

Xanthomonas euvesicatoria causes bacterial spot disease in leaves, roots, fruits and stems of pepper plants. Identification of this phytopathogen in jalapeno seeds from Delicias, Chihuahua, Mexico and diseased plants from New Mexico, USA, was carried out by isolation on semiselective media, pathogenicity assays and biochemical tests. Mexican oregano (Lippia berlandieri) essential oil was tested in vitro against Xanthomonas euvesicatoria. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were performed and the oil showed an inhibition of bacterial growth in concentrations of 0.01 mg/ml and a bactericidal effect in concentrations of 0.05 mg/ml. Oregano essential oil is reported to have antimicrobial activities due to the effect of high content of carvacrol. Oregano oil had an MIC that was 10 times lower compared to pure carvacrol, since carvacrol content, measured by gas chromatography/mass spectrometry (GC/ MS) was only 30%. The antimicrobial effect in vivo was tested using a randomized complete block design model in a greenhouse. Disease severity, xanthomonad incidence as well as chlorophyll indices were calculated showing a strong inhibition of the disease, when seeds or foliage were treated with oregano oil. These results demonstrate the current commonality of xanthomonad pathogens on both sides of the Mexican-American border, and that oregano oil has potent antibacterial activity. Resumen Xanthomonas euvesicatoria es la bacteria agente causal de la marchitez bacteriana en hojas, raíces y frutos de chile jalapeño. Se realizó la identificación de este patógeno en las semillas de chile jalapeño provenientes de Delicias, Chihuahua, México y plantas enfermas provenientes del estado de Nuevo Mexico, EUA; a través de cultivo en medios semi-selectivos, ensayos de patogenicidad y pruebas bioquímicas. El aceite esencial del orégano mexicano (Lippia berlandieri) fue probado in vitro contra Xanthomonas euvesicatoria. Pruebas de concentración mínima inhibitoria (CMI) y concentración mínima bactericida (CMB) fueron determinadas y el aceite mostró una inhibición de crecimiento a concentraciones de 0.01 mg/ml y un efecto bactericida a concentraciones de 0.05 mg/ ml. El aceite esencial de orégano muestra actividades antibacterianas gracias al efecto de la alta concentración de carvacrol. El aceite de orégano mostró una CMI que fue 10 veces menor en comparación con el efecto de carvacrol puro, ya que la concentración determinada en el aceite por medio de cromatografía de gases/espectrometría de masas (GC/MS) fue de 30% de carvacrol. El efecto antibacteriano in vivo fue probado utilizando un diseño de bloques completos al azar en un invernadero. La severidad e incidencia de la enfermedad, así como los índices de clorofila, fueron calculados mostrando una inhibición de la enfermedad cuando las semillas u hojas de las plantas de chile se trataron con el aceite de orégano. Estos resultados demuestran la problemática de la bacteria Xanthomonas en las fronteras México-Americanas y que el aceite esencial de orégano ejerce una acción antibacteriana. Palabras clave: marchitez bacteriana, concentración mínima inhibitoria, Carvacrol

Observation of a nuclear recoil peak at the 100 eV scale induced by neutron capture

Coherent elastic neutrino-nucleus scattering and low-mass Dark Matter detectors rely crucially on the understanding of their response to nuclear recoils. We report the first observation of a nuclear recoil peak at around 112 eV induced by neutron capture. The measurement was performed with a CaWO$_4$ cryogenic detector from the NUCLEUS experiment exposed to a $^{252}$Cf source placed in a compact moderator. The measured spectrum is found in agreement with simulations and the expected peak structure from the single-$\gamma$ de-excitation of $^{183}$W is identified with 3 $\sigma$ significance. This result demonstrates a new method for precise, in-situ, and non-intrusive calibration of low-threshold experiments

Coherent elastic neutrino-nucleus scattering: Terrestrial and astrophysical applications

Coherent elastic neutrino-nucleus scattering (CE$\nu$NS) is a process in which neutrinos scatter on a nucleus which acts as a single particle. Though the total cross section is large by neutrino standards, CE$\nu$NS has long proven difficult to detect, since the deposited energy into the nucleus is $\sim$ keV. In 2017, the COHERENT collaboration announced the detection of CE$\nu$NS using a stopped-pion source with CsI detectors, followed up the detection of CE$\nu$NS using an Ar target. The detection of CE$\nu$NS has spawned a flurry of activities in high-energy physics, inspiring new constraints on beyond the Standard Model (BSM) physics, and new experimental methods. The CE$\nu$NS process has important implications for not only high-energy physics, but also astrophysics, nuclear physics, and beyond. This whitepaper discusses the scientific importance of CE$\nu$NS, highlighting how present experiments such as COHERENT are informing theory, and also how future experiments will provide a wealth of information across the aforementioned fields of physics

Coherent elastic neutrino-nucleus scattering: Terrestrial and astrophysical applications

Coherent elastic neutrino-nucleus scattering (CE$\nu$NS) is a process inwhich neutrinos scatter on a nucleus which acts as a single particle. Thoughthe total cross section is large by neutrino standards, CE$\nu$NS has longproven difficult to detect, since the deposited energy into the nucleus is$\sim$ keV. In 2017, the COHERENT collaboration announced the detection ofCE$\nu$NS using a stopped-pion source with CsI detectors, followed up thedetection of CE$\nu$NS using an Ar target. The detection of CE$\nu$NS hasspawned a flurry of activities in high-energy physics, inspiring newconstraints on beyond the Standard Model (BSM) physics, and new experimentalmethods. The CE$\nu$NS process has important implications for not onlyhigh-energy physics, but also astrophysics, nuclear physics, and beyond. Thiswhitepaper discusses the scientific importance of CE$\nu$NS, highlighting howpresent experiments such as COHERENT are informing theory, and also how futureexperiments will provide a wealth of information across the aforementionedfields of physics.<br

Pregnancy and neonatal outcomes of COVID-19: The PAN-COVID study

Objective To assess perinatal outcomes for pregnancies affected by suspected or confirmed SARS-CoV-2 infection. Methods Prospective, web-based registry. Pregnant women were invited to participate if they had suspected or confirmed SARS-CoV-2 infection between 1st January 2020 and 31st March 2021 to assess the impact of infection on maternal and perinatal outcomes including miscarriage, stillbirth, fetal growth restriction, pre-term birth and transmission to the infant. Results Between April 2020 and March 2021, the study recruited 8239 participants who had suspected or confirmed SARs-CoV-2 infection episodes in pregnancy between January 2020 and March 2021. Maternal death affected 14/8197 (0.2%) participants, 176/8187 (2.2%) of participants required ventilatory support. Pre-eclampsia affected 389/8189 (4.8%) participants, eclampsia was reported in 40/ 8024 (0.5%) of all participants. Stillbirth affected 35/8187 (0.4 %) participants. In participants delivering within 2 weeks of delivery 21/2686 (0.8 %) were affected by stillbirth compared with 8/4596 (0.2 %) delivering ≥ 2 weeks after infection (95 % CI 0.3–1.0). SGA affected 744/7696 (9.3 %) of livebirths, FGR affected 360/8175 (4.4 %) of all pregnancies. Pre-term birth occurred in 922/8066 (11.5%), the majority of these were indicated pre-term births, 220/7987 (2.8%) participants experienced spontaneous pre-term births. Early neonatal deaths affected 11/8050 livebirths. Of all neonates, 80/7993 (1.0%) tested positive for SARS-CoV-2. Conclusions Infection was associated with indicated pre-term birth, most commonly for fetal compromise. The overall proportions of women affected by SGA and FGR were not higher than expected, however there was the proportion affected by stillbirth in participants delivering within 2 weeks of infection was significantly higher than those delivering ≥ 2 weeks after infection. We suggest that clinicians’ threshold for delivery should be low if there are concerns with fetal movements or fetal heart rate monitoring in the time around infection

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P &lt; 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

Controlled ring-opening polymerization of lactones and lactide initiated by lanthanum isopropoxide, 2a: Mechanistic studies

The mechanism of ring-opening polymerization of some lactones and lactide initiated by lanthanum isopropoxide has been comprehensively investigated. NMR and viscosity analyses demonstrated that three active polymer chains grow per lanthanum atom and that. depending on the coordinating ability of the monomer, propagation proceeds on aggregated or unaggregated active species. It is also demonstrated that inter- and intramolecular side reactions are limited and that lanthanum-based initiator selectivity in ring-opening polymerization is analogous to that of aluminum ones

H atom density measurement using a combination of optical emission spectroscopy and Langmuir probes diagnostics

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Etude de la transmission et de la rétrodiffusion d'électrons d'énergie 0,05 à 3 MeV dans le domaine de la diffusion multiple

A knowledge of the motion of electrons in matter is of fundamental importance, particularly in scanning microscopy, in microanalysis and in space physics. We present our experimental results for monoenergetic electrons incident normal to polycrystalline targets under multiple scattering conditions. The measurement give information concerning the transmission and backscattering coefficients, the angular distributions and the path-length inside the specimen. We give analytic expressions that describe the experimental results accurately over a very wide range of energies (0.05-3 MeV).Le comportement des électrons dans la matière est d'un intérêt fondamental, notamment en microscopie à balayage, en microanalyse et en physique spatiale. Nous présentons dans cet article l'ensemble de nos résultats expérimentaux dans le domaine de la diffusion multiple pour un faisceau d'électrons monocinétiques tombant normalement sur des cibles polycristallines. Les mesures sont relatives aux coefficients de transmission et de rétrodiffusion, aux distributions angulaires, ainsi qu'au parcours entier des électrons dans la matière. Nous donnons des relations analytiques qui permettent de retrouver avec précision les résultats expérimentaux dans un vaste domaine énergétique (0,05 à 3 MeV)