PAM (pulse-amplitude-modulated) fluorescence measurements of motile microphytobenthic algae were carried out in June 1996 at Sylt, Germany. Comparisons between super(14)C-based and fluorescence-based ...production rates were made. A very high correlation between super(14)C- and fluorescence-based production rates was found for maximal production rates (P sub(max) values). super(14)C-based maximal production rates varied during the study period between 0.65 and 1.7 mg C/mg chl a/h, comparable to variations of P sub(max) measured with the fluorescence-based method. For other photosynthetic parameters alpha (maximum light utilization coefficient), E sub(k) (light saturation index), E sub(max) (light intensity at which P sub(max) is reached), differences between the 2 methods were much larger. Highest carbon quantum yields ( phi sub(ass)) (mol C/mol quanta absorbed) were obtained at low irradiances. Considering the whole range of investigated carbon quantum yields, we found that initially these values decreased at low to moderate irradiances without a concomitant decline of the actual photochemical efficiency (F sub(m)'-F)/F sub(m)' (F and F sub(m)': minimal and maximal fluorescence signals in the light). Therefore, a high linearity between the actual photochemical efficiency and the carbon quantum yield could only be observed up to values of 0.018 mol C/mol quanta. This is different to higher plants, for which linearity can be observed up to carbon quantum yields of 0.042 mol C/mol quanta. It was shown that, for the calculation of the overall production rates based on the fluorescence method, it is necessary to carefully measure the mean specific absorption coefficient (a*) of the algae. Unless this is achieved, PAM measurements cannot be used to calculate absolute production rates.
The COVID-19 pandemic led to a large global effort to sequence SARS-CoV-2 genomes from patient samples to track viral evolution and inform public health response. Millions of SARS-CoV-2 genome ...sequences have been deposited in global public repositories. The Canadian COVID-19 Genomics Network (CanCOGeN - VirusSeq), a consortium tasked with coordinating expanded sequencing of SARS-CoV-2 genomes across Canada early in the pandemic, created the Canadian VirusSeq Data Portal, with associated data pipelines and procedures, to support these efforts. The goal of VirusSeq was to allow open access to Canadian SARS-CoV-2 genomic sequences and enhanced, standardized contextual data that were unavailable in other repositories and that meet FAIR standards (Findable, Accessible, Interoperable and Reusable). In addition, the Portal data submission pipeline contains data quality checking procedures and appropriate acknowledgement of data generators that encourages collaboration. From inception to execution, the portal was developed with a conscientious focus on strong data governance principles and practices. Extensive efforts ensured a commitment to Canadian privacy laws, data security standards, and organizational processes. This Portal has been coupled with other resources like Viral AI and was further leveraged by the Coronavirus Variants Rapid Response Network (CoVaRR-Net) to produce a suite of continually updated analytical tools and notebooks. Here we highlight this Portal, including its contextual data not available elsewhere, and the 'Duotang', a web platform that presents key genomic epidemiology and modeling analyses on circulating and emerging SARS-CoV-2 variants in Canada. Duotang presents dynamic changes in variant composition of SARS-CoV-2 in Canada and by province, estimates variant growth, and displays complementary interactive visualizations, with a text overview of the current situation. The VirusSeq Data Portal and Duotang resources, alongside additional analyses and resources computed from the Portal (COVID-MVP, CoVizu), are all open-source and freely available. Together, they provide an updated picture of SARS-CoV-2 evolution to spur scientific discussions, inform public discourse, and support communication with and within public health authorities. They also serve as a framework for other jurisdictions interested in open, collaborative sequence data sharing and analyses.
Nucl.Instrum.Meth.A540:295-304,2005 A small drift chamber was read out by means of a MediPix2 readout chip as
direct anode. A Micromegas foil was placed 50 $\mu$m above the chip, and
electron ...multiplication occurred in the gap. With a He/Isobutane 80/20 mixture,
gas multiplication factors up to tens of thousands were achieved, resulting in
an efficiency for detecting single electrons of better than 90% . We recorded
many frames containing 2D images with tracks from cosmic muons. Along these
tracks, electron clusters were observed, as well as delta-rays.
We report on measurements of the inclusive production rate of $\Sigma^+$ and $\Sigma^0$ baryons in hadronic Z decays collected with the L3 detector at LEP. The $\Sigma^+$ baryons are detected through ...the decay $\Sigma^+ \rightarrow {\rm p} \pi^0$, while the $\Sigma^0$ baryons are detected via the decay mode $\Sigma^0 \rightarrow \Lambda \gamma$. The average numbers of $\Sigma^+$ and $\Sigma^0$ per hadronic Z decay are measured to be: \begin{eqnarray*} \left N_{\Sigma^+} \right + \left N_{\bar{\Sigma}^+} \right & = & 0.114 \pm 0.011_{\mbox{\it \small stat}} \pm 0.009_{\mbox{\it \small syst}} \\ \left N_{\Sigma^0} \right + \left N_{\bar{\Sigma}^0} \right & = & 0.095 \pm 0.015_{\mbox{\it \small stat}} \pm 0.013_{\mbox{\it \small syst}} \ \mbox{.} \end{eqnarray*} These rates are found to be higher than the predictions from Monte Carlo hadronization models and analytical parameterizations of strange baryon production.
A search for charginos nearly mass-degenerate with the lightestsupersymmetric particle isperformed using the 176 {pb$^{-1}$ of data collected at 189 {Ge\kern -0.1em V} in 1998 with the L3detector. ...Mass differences between the chargino and the lightest supersymmetric particlebelow 4 {Ge\kern -0.1em V} are considered.The presence of a high transverse momentum photon is required to single out the signal from the photon-photon interaction background. No evidence for charginos is found and upper limits on the cross section for chargino pair production are set. For the first time, in the case ofheavy scalar leptons, chargino mass limits are obtained for any $\tilde{\chi}^{\pm}_1 - \tilde{\chi}^0_1$ mass difference.
A first measurement of the cross section of the process$\rm e^+e^-\rightarrow Z\gamma\gamma$ is reported using a total integrated luminosity of 231\,pb$^{-1}$collected with the L3 detector at ...centre-of-mass energiesof 182.7\,GeV and 188.7\,GeV. By selectinghadronic events with two isolated photonsthe $\rm e^+e^-\rightarrow Z\gamma\gamma$cross section is measured to be$ 0.49^{+0.20}_{-0.17}\pm0.04\,{\mathrm{pb}}$ at 182.7\,GeV and $0.47 \pm 0.10\pm0.04\,{\mathrm{pb}}$ at 188.7\,GeV. Themeasurements are consistent with Standard Model expectations.Limits on Quartic Gauge Boson Couplings $a_0/\Lambda^2$ and $a_c/\Lambda^2$ of-0.009\, GeV$^{-2}$ $ a_0/\Lambda^2 $ 0.008\,GeV$^{-2}$ and-0.007\,GeV$^{-2}$ $ a_c/\Lambda^2 $ 0.013\,GeV$^{-2}$ are derived at95\(onfidence level.
A small drift chamber was read out by means of a MediPix2 readout chip as direct anode. A Micromegas foil was placed 50 \(\mu\)m above the chip, and electron multiplication occurred in the gap. With ...a He/Isobutane 80/20 mixture, gas multiplication factors up to tens of thousands were achieved, resulting in an efficiency for detecting single electrons of better than 90% . We recorded many frames containing 2D images with tracks from cosmic muons. Along these tracks, electron clusters were observed, as well as delta-rays.
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