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Abstract Terminalia argentea tree, native to Brazil, is widely used in landscaping, recovering degraded areas, its wood, coal production, and the bark or leaf extracts has medicinal use. Despite of its importance, the arthropod fauna associated to this plant and its interspecific relationships still needs further studies. The objectives of this study were to evaluate the arthropods, their ecological indices and the distribution in the leaf faces on T. argentea saplings. The numbers of phytophagous insects (e.g., Cephalocoema sp.), pollinators (e.g., Tetragonisca angustula), and natural enemies (e.g., Oxyopidae), and their ecological indices (e.g., species richness), were higher on the adaxial leaf faces on T. argentea saplings. Aggregated distribution of phytophagous insects (e.g., Aphis spiraecola), pollinators (e.g., Trigona spinipes), and natural enemies (e.g., Camponotus sp.) on T. argentea saplings was observed. Abundance, diversity, and species richness of natural enemies correlated, positively, with those of phytophagous and pollinators insects. Predators and tending ants followed their prey and sucking insects, respectively. Tending ants protected sucking insects against predators, and reduced chewing insects. The high number of Cephalocoema sp. on T. argentea saplings is a problem, because this insect can feed on leaves of this plant, but its preference for the adaxial leaf face favors its control. The aggregation behavior of arthropods on T. argentea saplings favors the control of potential pests of this plant. There seems to be competition between tending ants for space and food resources on T. argentea saplings. Resumo Terminalia argentea, árvore nativa do Brasil, é muito utilizada no paisagismo, na recuperação de áreas degradadas, sua madeira na produção de carvão e o extrato da casca ou das folhas tem uso medicinal. Apesar de sua importância, a fauna de artrópodes associada a esta planta e suas relações interespecíficas ainda carecem de estudos mais aprofundados. Os objetivos deste estudo foram avaliar os artrópodes, seus índices ecológicos e a distribuição nas faces foliares de mudas de T. argentea. O número de insetos fitófagos (ex.: Cephalocoema sp.), polinizadores (ex.: Tetragonisca angustula), e inimigos naturais (ex.: Oxyopidae), e seus índices ecológicos (ex.: riqueza de espécies), foram maiores nas faces adaxiais das folhas das mudas de T. argentea. Foi observada uma distribuição agregada de insetos fitófagos (ex.: Aphis spiraecola), polinizadores (ex.: Trigona spinipes) e inimigos naturais (ex.: Camponotus sp.) em mudas de T. argentea. A abundância, diversidade e riqueza de espécies de inimigos naturais correlacionaram-se, positivamente, com as de insetos fitófagos e polinizadores. Os predadores e as formigas cuidadoras seguiram as suas presas e os insetos sugadores, respectivamente. As formigas cuidadoras protegeram os insetos sugadores contra os predadores e reduziram os insetos mastigadores. O elevado número de Cephalocoema sp. em mudas de T. argentea é um problema, pois esse inseto pode se alimentar de folhas dessa planta, mas sua preferência pela face adaxial da folha favorece seu controle. O comportamento de agregação de artrópodes em mudas de T. argentea favorece o controle de potenciais pragas dessa planta. Parece haver competição entre as formigas cuidadoras por espaço e recursos alimentares nas mudas de T. argentea.

Bispo et al discuss their study on the recovery of a degraded area using Platycyamus regnellii (Fabaceae) saplings. The degradation of nature, particularly the removal of vegetation cover from the soil, is a significant concern in expert debates. In Brazil, to restore these degraded areas, pioneer plants such as Acacia mangium and A. auriculiformis are commonly used. However, the native tree Platycyamus regnellii is also a promising option due to its various uses and ecological characteristics. Insects play a crucial role in assessing the success of restoration efforts, as they are highly sensitive to environmental changes. The study aimed to evaluate the numbers and diversity of leaves, branches, and different insect groups on P. regnellii saplings in a degraded area. The results showed that older saplings had larger canopies and greater ground coverage, leading to higher abundances and species richness of herbivorous and pollinator insects, as well as predators.

Oral outpatient treatment for Covid-19 is needed. In this phase 3, double-blind, randomized, controlled trial, molnupiravir, a small-molecule antiviral, was studied in unvaccinated patients with less than 5 days of Covid-19 illness. By day 29, hospitalization for progression of Covid-19 was lower with molnupiravir (6.8%) than with placebo (9.7%).

Background In this study, we designed a novel genetic circuit sensitive to Cd 2+ , Zn 2+ and Pb 2+ by mimicking the CadA/CadR operon system mediated heavy metal homeostasis mechanism of Pseudomonas aeruginosa . The regular DNA motifs on natural operon were reconfigured and coupled with the enhanced Green Fluorescent Protein (eGFP) reporter to develop a novel basic NOT type logic gate CadA/CadR- eGFP to respond metal ions mentioned above. A Genetically Engineered Microbial (GEM)-based biosensor ( E.coli -BL21:pJET1.2- CadA/CadR- eGFP) was developed by cloning the chemically synthesised CadA/CadR- eGFP gene circuit into pJET1.2-plasmid and transforming into Escherichia coli ( E. coli )-BL21 bacterial cells. Results The GEM-based biosensor cells indicated the reporter gene expression in the presence of Cd 2+ , Zn 2+ and Pb 2+ either singly or in combination. Further, the same biosensor cells calibrated for fluorescent intensity against heavy metal concentration generated linear graphs for Cd 2+ , Zn 2+ and Pb 2+ with the R 2 values of 0.9809, 0.9761 and 0.9758, respectively as compared to non-specific metals, Fe 3+ (0.0373), AsO 4 3− (0.3825) and Ni 2+ (0.8498) making our biosensor suitable for the detection of low concentration of the former metal ions in the range of 1–6 ppb. Furthermore, the GEM based biosensor cells were growing naturally within the concentration range of heavy metals, at 37 °C and optimum pH = 7.0 in the medium, resembling the characteristics of wildtype E.coli . Conclusion Finally, the novel GEM based biosensor cells developed in this study can be applied for detection of targeted heavy metals in low concentration ranges (1–6 ppb) at normal bacterial physiological conditions.

Yellow fever is an acute infectious disease caused by prototype virus of the genus Flavivirus. It is endemic in Africa and South America where it represents a serious public health problem causing epidemics of hemorrhagic fever with mortality rates ranging from 20% to 50%. There is no available antiviral therapy and vaccination is the primary method of disease control. Although the attenuated vaccines for yellow fever show safety and efficacy it became necessary to develop a new yellow fever vaccine due to the occurrence of rare serious adverse events, which include visceral and neurotropic diseases. The new inactivated vaccine should be safer and effective as the existing attenuated one. In the present study, the immunogenicity of an inactivated 17DD vaccine in C57BL/6 mice was evaluated. The yellow fever virus was produced by cultivation of Vero cells in bioreactors, inactivated with β-propiolactone, and adsorbed to aluminum hydroxide (alum). Mice were inoculated with inactivated 17DD vaccine containing alum adjuvant and followed by intracerebral challenge with 17DD virus. The results showed that animals receiving 3 doses of the inactivated vaccine (2μg/dose) with alum adjuvant had neutralizing antibody titers above the cut-off of PRNT50 (Plaque Reduction Neutralization Test). In addition, animals immunized with inactivated vaccine showed survival rate of 100% after the challenge as well as animals immunized with commercial attenuated 17DD vaccine.

Astrophysical shocks are commonly revealed by the non-thermal emission of energetic electrons accelerated in situ1–3. Strong shocks are expected to accelerate particles to very high energies4–6; however, they require a source of particles with velocities fast enough to permit multiple shock crossings. While the resulting diffusive shock acceleration4 process can account for observations, the kinetic physics regulating the continuous injection of non-thermal particles is not well understood. Indeed, this injection problem is particularly acute for electrons, which rely on high-frequency plasma fluctuations to raise them above the thermal pool7,8. Here we show, using laboratory laser-produced shock experiments, that, in the presence of a strong magnetic field, significant electron pre-heating is achieved. We demonstrate that the key mechanism in producing these energetic electrons is through the generation of lower-hybrid turbulence via shock-reflected ions. Our experimental results are analogous to many astrophysical systems, including the interaction of a comet with the solar wind9, a setting where electron acceleration via lower-hybrid waves is possible.

Severe drought in a tropical forest ecosystem suppresses photosynthetic carbon uptake and plant maintenance respiration, but growth is maintained, suggesting that, overall, less carbon is available for tree tissue maintenance and defence, which may cause the subsequent observed increase in tree mortality. Effect of short-term drought on forest ecosytems The underlying mechanisms that determine the response of tropical forest ecosystems to drought remain poorly understood. Based on observations from a network of intensively measured forest plots in the Amazon basin, this study shows that severe drought suppresses photosynthetic carbon uptake and plant maintenance respiration. Plant growth is maintained however, suggesting that less carbon is available for tree tissue maintenance and defence — which may explain the observed increase in tree mortality that follows a drought. In 2005 and 2010 the Amazon basin experienced two strong droughts 1 , driven by shifts in the tropical hydrological regime 2 possibly associated with global climate change 3 , as predicted by some global models 3 . Tree mortality increased after the 2005 drought 4 , and regional atmospheric inversion modelling showed basin-wide decreases in CO 2 uptake in 2010 compared with 2011 (ref. 5 ). But the response of tropical forest carbon cycling to these droughts is not fully understood and there has been no detailed multi-site investigation in situ . Here we use several years of data from a network of thirteen 1-ha forest plots spread throughout South America, where each component of net primary production (NPP), autotrophic respiration and heterotrophic respiration is measured separately, to develop a better mechanistic understanding of the impact of the 2010 drought on the Amazon forest. We find that total NPP remained constant throughout the drought. However, towards the end of the drought, autotrophic respiration, especially in roots and stems, declined significantly compared with measurements in 2009 made in the absence of drought, with extended decreases in autotrophic respiration in the three driest plots. In the year after the drought, total NPP remained constant but the allocation of carbon shifted towards canopy NPP and away from fine-root NPP. Both leaf-level and plot-level measurements indicate that severe drought suppresses photosynthesis. Scaling these measurements to the entire Amazon basin with rainfall data, we estimate that drought suppressed Amazon-wide photosynthesis in 2010 by 0.38 petagrams of carbon (0.23–0.53 petagrams of carbon). Overall, we find that during this drought, instead of reducing total NPP, trees prioritized growth by reducing autotrophic respiration that was unrelated to growth. This suggests that trees decrease investment in tissue maintenance and defence, in line with eco-evolutionary theories that trees are competitively disadvantaged in the absence of growth 6 . We propose that weakened maintenance and defence investment may, in turn, cause the increase in post-drought tree mortality observed at our plots.

About 10 μs after the Big Bang, the universe was filled—in addition to photons and leptons—with strong-interaction matter consisting of quarks and gluons, which transitioned to hadrons at temperatures close to kT = 150 MeV and densities several times higher than those found in nuclei. This quantum chromodynamics (QCD) matter can be created in the laboratory as a transient state by colliding heavy ions at relativistic energies. The different phases in which QCD matter may exist depend for example on temperature, pressure or baryochemical potential, and can be probed by studying the emission of electromagnetic radiation. Electron–positron pairs emerge from the decay of virtual photons, which immediately decouple from the strong interaction, and thus provide information about the properties of QCD matter at various stages. Here, we report the observation of virtual photon emission from baryon-rich QCD matter. The spectral distribution of the electron–positron pairs is nearly exponential, providing evidence for a source of temperature in excess of 70 MeV with constituents whose properties have been modified, thus reflecting peculiarities of strong-interaction QCD matter. Its bulk properties are similar to the dense matter formed in the final state of a neutron star merger, as apparent from recent multimessenger observation.

Why do forest productivity and biomass decline with elevation? To address this question, research to date generally has focused on correlative approaches describing changes in woody growth and biomass with elevation. We present a novel, mechanistic approach to this question by quantifying the autotrophic carbon budget in 16 forest plots along a 3300m elevation transect in Peru. Low growth rates at high elevations appear primarily driven by low gross primary productivity (GPP), with little shift in either carbon use efficiency (CUE) or allocation of net primary productivity (NPP) between wood, fine roots and canopy. The lack of trend in CUE implies that the proportion of photosynthate allocated to autotrophic respiration is not sensitive to temperature. Rather than a gradual linear decline in productivity, there is some limited but nonconclusive evidence of a sharp transition in NPP between submontane and montane forests, which may be caused by cloud immersion effects within the cloud forest zone. Leaf-level photosynthetic parameters do not decline with elevation, implying that nutrient limitation does not restrict photosynthesis at high elevations. Our data demonstrate the potential of whole carbon budget perspectives to provide a deeper understanding of controls on ecosystem functioning and carbon cycling.