Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) compromises the ability of military forces to fulfill missions. At the beginning of May ...2020, 22 out of 70 Belgian soldiers deployed to a military education and training center in Maradi, Niger, developed mild COVID-19 compatible symptoms. Immediately upon their return to Belgium, and two weeks later, all seventy soldiers were tested for SARS-CoV-2 RNA (RT-qPCR) and antibodies (two immunoassays). Nine soldiers had at least one positive COVID-19 diagnostic test result. Five of them exhibited COVID-19 symptoms (mainly anosmia, ageusia, and fever), while four were asymptomatic. In four soldiers, SARS-CoV-2 viral load was detected and the genomes were sequenced. Conventional and genomic epidemiological data suggest that these genomes have an African most recent common ancestor and that the Belgian military service men were infected through contact with locals. The medical military command implemented testing of all Belgian soldiers for SARS-CoV-2 viral load and antibodies, two to three days before their departure on a mission abroad or on the high seas, and for specific missions immediately upon their return in Belgium. Some military operational settings (e.g., training camps in austere environments and ships) were also equipped with mobile infectious disease (COVID-19) testing capacity.
Premise
Most studies of the movement of orchid fruits and roots during plant development have focused on morphological observations; however, further genetic analysis is required to understand the ...molecular mechanisms underlying this phenomenon. A precise tool is required to observe these movements and harvest tissue at the correct position and time for transcriptomics research.
Methods
We utilized three‐dimensional (3D) micro–computed tomography (CT) scans to capture the movement of fast‐growing Erycina pusilla roots, and built an integrated bioinformatics pipeline to process 3D images into 3D time‐lapse videos. To record the movement of slowly developing E. pusilla and Phalaenopsis equestris fruits, two‐dimensional (2D) photographs were used.
Results
The E. pusilla roots twisted and resupinated multiple times from early development. The first period occurred in the early developmental stage (77–84 days after germination DAG) and the subsequent period occurred later in development (140–154 DAG). While E. pusilla fruits twisted 45° from 56–63 days after pollination (DAP), the fruits of P. equestris only began to resupinate a week before dehiscence (133 DAP) and ended a week after dehiscence (161 DAP).
Discussion
Our methods revealed that each orchid root and fruit had an independent direction and degree of torsion from the initial to the final position. Our innovative approaches produced detailed spatial and temporal information on the resupination of roots and fruits during orchid development.
More than a year after the first identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as the causative agent of the 2019 coronavirus disease (COVID-19) in China, the ...emergence and spread of genomic variants of this virus through travel raise concerns regarding the introduction of lineages in previously unaffected regions, requiring adequate containment strategies. Concomitantly, such introductions fuel worries about a possible increase in transmissibility and disease severity, as well as a possible decrease in vaccine efficacy. Military personnel are frequently deployed on missions around the world. As part of a COVID-19 risk mitigation strategy, Belgian Armed Forces that engaged in missions and operations abroad were screened (7683 RT-qPCR tests), pre- and post-mission, for the presence of SARS-CoV-2, including the identification of viral lineages. Nine distinct viral genotypes were identified in soldiers returning from operations in Niger, the Democratic Republic of the Congo, Afghanistan, and Mali. The SARS-CoV-2 variants belonged to major clades 19B, 20A, and 20B (Nextstrain nomenclature), and included “variant of interest” B.1.525, “variant under monitoring” A.27, as well as lineages B.1.214, B.1, B.1.1.254, and A (pangolin nomenclature), some of which are internationally monitored due to the specific mutations they harbor. Through contact tracing and phylogenetic analysis, we show that isolation and testing policies implemented by the Belgian military command appear to have been successful in containing the influx and transmission of these distinct SARS-CoV-2 variants into military and civilian populations.
Objectives The aim of the study was to study antimicrobial susceptibility in Escherichia coli, Salmonella, Campylobacter and Enterococcus recovered from chickens, pigs and cattle using uniform ...methodology. Methods Intestinal samples were taken at slaughter in five EU countries per host and bacteria isolated in national laboratories. MICs were determined in a central laboratory of key antimicrobials used in human medicine. Clinical resistance was based on CLSI breakpoints and decreased susceptibility on EFSA epidemiological cut-off values. Results Isolation rates from a total of 1500 samples were high for E. coli (n=1465), low for Salmonella (n=205) and intermediate for Campylobacter (n=785) and Enterococcus (n=718). Resistance prevalence varied among antibiotics, bacteria, hosts and countries. For E. coli and Salmonella, clinical resistance to newer compounds (cefepime, cefotaxime, ciprofloxacin) was absent or low, but a decreased susceptibility was apparent, particularly in chickens. Clinical resistance to older compounds (except colistin and gentamicin) was variable and higher. For Campylobacter jejuni from chickens, ciprofloxacin resistance was markedly higher than in isolates from cattle. Clinical resistance to erythromycin was absent for both hosts; decreased susceptibility very low. Similar trends were determined for Campylobacter coli, but C. jejuni was less resistant. None of the enterococcal strains was resistant to linezolid, but a few displayed resistance to ampicillin or vancomycin. Resistance prevalence to quinupristin/dalfopristin was clearly higher. Conclusions Antimicrobial resistance among enteric organisms in food animals varied among countries, particularly for older antimicrobials, but clinical resistance to essential compounds used to treat disease in humans was generally zero or low. In the absence of clinical resistance to newer compounds in E. coli and Salmonella, the apparent decreased susceptibility should be monitored carefully.
Sulfite is often added to beverages as an antioxidant and antimicrobial agent. In fermented beverages, sulfite is also naturally produced by yeast cells. However, sulfite causes adverse health ...effects in asthmatic patients and accurate measurement of the sulfite concentration is therefore very important. Current sulfite analysis methods are time- and reagent-consuming and often require costly equipment. Here, we present a system allowing sensitive, ultralow-volume sulfite measurements based on a reusable glass-silicon microdroplet platform on which microdroplet generation, addition of enzymes through chemical-induced emulsion destabilization and pillar-induced droplet merging, emulsion restabilization, droplet incubation, and fluorescence measurements are integrated. In a first step, we developed and verified a fluorescence-based enzymatic assay for sulfite by measuring its analytical performance (LOD, LOQ, the dynamic working range, and the influence of salts, colorant, and sugars) and comparing fluorescent microplate readouts of fermentation samples with standard colorimetric measurements using the 5,5′-dithiobis-(2-nitrobenzoic acid) assay of the standard Gallery Plus Beermaster analysis platform. Next, samples were analyzed on the microdroplet platform, which also showed good correlation with the standard colorimetric analysis. Although the presented platform does not allow stable reinjection of droplets due to the presence of a tight array of micropillars at the fluidics entrances to prevent channel clogging by dust, removing the pillars, and integrating miniaturized pumps and optics in a future design would allow to use this platform for high-throughput, automated, and portable screening of microbes, plant, or mammalian cells.
Graphical abstract
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JNJ‐64264681 is an irreversible covalent inhibitor of Bruton's tyrosine kinase. This phase 1, first‐in‐human, 2‐part (single‐ascending dose SAD; multiple‐ascending dose MAD) study evaluated the ...safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD; Bruton's tyrosine kinase occupancy BTKO) of JNJ‐64264681 oral solution in healthy participants. For SAD (N = 78), 6 increasing doses of JNJ‐64264681 (4–400 mg) or placebo were evaluated in fasted males. The effects of sex, food, and a capsule formulation were evaluated in separate cohorts. For MAD (N = 27), sequential cohorts of male and female participants received 36/100/200 mg JNJ‐64264681 once daily for 10 days. JNJ‐64264681 exposure (peak concentration; area under the concentration‐time curve) was less than dose proportional from 4 mg to 36 mg. Dose‐normalized area under the concentration‐time curves following the 36 mg and 100 mg doses were generally similar. The mean terminal half‐life was 1.6–13.2 hours. With multiple doses, steady state was achieved by day 2. A semimechanistic PK/PD model was developed using the first 5 SAD cohorts’ data to predict %BTKO in MAD cohorts. PK/PD model guided dose‐escalation, and all participants in the 200/400 mg single‐dose cohorts achieved ≥90% BTKO at 4 hours after dosing (peak) with prolonged occupancy. As BTKO data became available from MAD cohorts, it was found that observed BTKO data were consistent with model predictions. JNJ‐64264681 showed no safety signals of concern. Overall, safety, tolerability, PK, BTKO, and PK/PD modeling guided the rationale for dose selection for the subsequent first‐in‐patient lymphoma studies.
Fruits play a crucial role in seed dispersal. They open along dehiscence zones. Fruit dehiscence zone formation has been intensively studied in Arabidopsis thaliana. However, little is known about ...the mechanisms and genes involved in the formation of fruit dehiscence zones in species outside the Brassicaceae. The dehiscence zone of A. thaliana contains a lignified layer, while dehiscence zone tissues of the emerging orchid model Erycina pusilla include a lipid layer. Here we present an analysis of evolution and development of fruit dehiscence zones in orchids. We performed ancestral state reconstructions across the five orchid subfamilies to study the evolution of selected fruit traits and explored dehiscence zone developmental genes using RNA-seq and qPCR. We found that erect dehiscent fruits with non-lignified dehiscence zones and a short ripening period are ancestral characters in orchids. Lignified dehiscence zones in orchid fruits evolved multiple times from non-lignified zones. Furthermore, we carried out gene expression analysis of tissues from different developmental stages of E. pusilla fruits. We found that fruit dehiscence genes from the MADS-box gene family and other important regulators in E. pusilla differed in their expression pattern from their homologs in A. thaliana. This suggests that the current A. thaliana fruit dehiscence model requires adjustment for orchids. Additionally, we discovered that homologs of A. thaliana genes involved in the development of carpel, gynoecium and ovules, and genes involved in lipid biosynthesis were expressed in the fruit valves of E. pusilla, implying that these genes may play a novel role in formation of dehiscence zone tissues in orchids. Future functional analysis of developmental regulators, lipid identification and quantification can shed more light on lipid-layer based dehiscence of orchid fruits.
A mechanistic oxygen transfer model was developed and applied to a flow-through hollow-fiber membrane-aerated biofilm reactor. Model results are compared to conventional clean water test results as ...well as performance data obtained when an actively nitrifying biofilm was present on the fibers. With the biofilm present, oxygen transfer efficiencies between 30 and 55% were calculated from the measured data including the outlet gas oxygen concentration, ammonia consumption stoichiometry, and oxidized nitrogen production stoichiometry, all of which were in reasonable agreement. The mechanistic model overpredicted the oxygen transfer by a factor of 1.3 relative to the result calculated from the outlet gas oxygen concentration, which was considered the most accurate of the measured benchmarks. A mass transfer coefficient derived from the clean water testing with oxygen sensors at the membrane-liquid interface was the most accurate of the predictive models (overpredicted by a factor of 1.1) while a coefficient determined by measuring bulk liquid dissolved oxygen underpredicted the oxygen transfer by a factor of 3. The mechanistic model was found to be an adequate tool for design because it used the published diffusion and partition coefficients rather than requiring small-scale testing to determine the system-specific mass transfer coefficients.
•Examines the energy level alignment at the interface of zinc-tetraphenylporphyrin with CoCp2∗.•Analyzed using a transfer-doping model involving integer charge transfer.•Doping is limited to the ...first monolayer of CoCp2∗, with further adlayers remaining neutral.•Doping changes from surface molecular doping to bulk metallic doping after annealing.
N-type doping of the organic semiconductor zinc tetraphenylporphyrin (ZnTPP) by overlayers of the reducing molecule decamethylcobaltocene (CoCp2∗) is demonstrated using photoelectron spectroscopy. A transfer doping model involving integer charge transfer between molecules reproduces quantitatively all measured level shifts as a function of CoCp2∗ coverage using the ionisation potential of CoCp2∗ and the electron affinity of ZnTPP as sole input parameters. The model yields the experimentally observed limitation of doping to the first monolayer of cobaltocene while further layers remain neutral without the need to resort to special bonding arrangements for the first monolayer. Temperature-dependent studies reveal that doping is still present at room temperature, despite the high vapour pressure of CoCp2∗. Higher annealing temperatures initiate CoCp2∗ molecular dissociation and diffusion of Co atoms into the ZnTPP film. Hence, the nature of doping changes from surface molecular transfer doping to bulk metallic doping as a function of temperature.
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► The energy level alignment at the ZnTPP/C60F48 interface was experimentally investigated. ► Ionized and neutral C60F48 were identified using high-resolution photoelectron ...spectroscopy. ► The C60F48 acceptor state energy was determined from the experimentally evaluated doping efficiency. ► The energy offset is a consequence of the interplay between Fermi statistics in combination with an interfacial potential.
High resolution synchrotron-based core level spectroscopy was used to examine the energy level alignment at the interface of zinc–tetraphenylporphyrin films doped by the surface acceptor C60F48. Two distinct fluorofullerene charge states were identified, corresponding to ionized and neutral molecules, and their relative concentration as a function of coverage was used to evaluate the probability of occupation of the acceptor lowest unoccupied molecular orbital (LUMO). From an initial acceptor energy of −0.25eV, the C60F48 LUMO shifts upwards with coverage due to a doping-induced interfacial dipole potential, and stabilization of the LUMO at an energy 0.45eV above the Fermi energy was obtained. While the energy difference upon saturation is consistent with the results obtained for other donor–acceptor systems that have been interpreted as Fermi level pinning, the present work shows that the energy offset is a direct consequence of the interplay between Fermi–Dirac statistics in combination with the interfacial dipole potential.
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