JURNAL AGROTEKNOLOGI
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Rapid evolution generates synergism between multiple stressors: Linking theory and an evolution experiment
No full textGlobal change encompasses many co-occurring anthropogenic stressors. Understanding the interactions between these multiple stressors, whether they be additive, antagonistic or synergistic, is critical for ecosystem managers when prioritizing which stressors to mitigate in the face of global change. While such interactions between stressors appear prevalent, it remains unclear if and how these interactions change over time, as the majority of multiple-stressor studies rarely span multiple generations of study organisms. Although meta-analyses have reported some intriguing temporal trends in stressor interactions, for example that synergism may take time to emerge, the mechanistic basis for such observations is unknown. In this study, by analysing data from an evolution experiment with the rotifer Brachionus calyciflorus (~35 generations and 31,320 observations), we show that adaptation to multiple stressors shifts stressor interactions towards synergism. We show that trade-offs, where populations cannot optimally perform multiple tasks (i.e. adapting to multiple stressors), generate this bias towards synergism. We also show that removal of stressors from evolved populations does not necessarily increase fitness and that there is variation in the evolutionary trajectories of populations that experienced the same stressor regimes. Our results highlight outstanding questions at the interface between evolution and global change biology, and illustrate the importance of considering rapid adaptation when managing or restoring ecosystems subjected to multiple stressors under global change
Insights on COVID-19 impacts, challenges and opportunities for India’s biodiversity research: from complexity to building adaptations
No full textThe COVID-19 pandemic has impacted every sphere of human society. The paradigm shift of focus to COVID-related research and management has significantly affected various scientific domains, including biodiversity conservation. We assessed the perceptions of early-career researchers working for biodiversity conservation across India, to understand the impacts of the ongoing pandemic on their research. We administered an online questionnaire survey to 565 respondents, who identified four key areas that are affected by the pandemic: (1) research, (2) conservation (3) education, and (4) communication and networking. Respondents (89.2%) perceived that their fieldwork, followed by travel for meetings and funding were the most affected due to COVID-19 outbreak and subsequent lockdown. Nonetheless, responses on the impact varied between different professional categories and were disproportionate. Our study highlights that majority of the respondents (80%) advocate for stakeholder-driven policies and management practices as the most effective strategy to promote biodiversity conservation, in the post-COVID-19 world. To this end, as a post-pandemic response, we propose holistic solutions such as optimising research funding and collaborations, and supporting and strengthening them by citizen science and big data analytics. Our findings and recommendations will also serve as a paradigm for post- COVID-19 biodiversity policy, advocacy and implementation of the post 2020 biodiversity action plan that supports eco civilization
Multi-k spin ordering in CaFe3Ti4O12 stabilized by spin-orbit coupling and further-neighbor exchange
No full textOrthogonal spin ordering is rarely observed in magnetic oxides because nearest-neighbor symmetric Heisenberg superexchange interactions usually dominate. We have discovered that in the quadruple perovskite CaFe3Ti4O12, where only the S=2 Fe2+ ion is magnetic, long-range magnetic order consisting of an unusual arrangement of three interpenetrating orthogonal sublattices is stabilized. Each magnetic sublattice corresponds to a set of FeO4 square planes sharing a common orientation. This multi-k magnetic spin ordering is the result of fourth-neighbor spin couplings with a strong easy-axis anisotropy. In an applied magnetic field, each sublattice tends towards ferromagnetic alignment, but remains polarized by internal magnetic fields generated by the others, thus stabilizing in a noncollinear canted ferromagnetic structure. CaFe3Ti4O12 provides a rare example of how nontrivial long-range spin order can arise when near-neighbor Heisenberg superexchange is quenched
Noble gas signatures constrain oil-field water as the carrier phase of hydrocarbons occurring in shallow aquifers in the San Joaquin Basin, USA
No full textNoble gases record fluid interactions in multiphase subsurface environments through fractionation processes during fluid equilibration. Water in the presence of hydrocarbons at the subsurface acquires a distinct elemental signature due to the difference in solubility between these two fluids. We find the atmospheric noble gas signature in produced water is partially preserved after hydrocarbons production and water disposal to unlined ponds at the surface. This signature is distinct from meteoric water and can be used to trace oil-field water seepage into groundwater aquifers. We analyse groundwater (n = 30) and fluid disposal pond (n = 2) samples from areas overlying or adjacent to the Fruitvale, Lost Hills, and South Belridge Oil Fields in the San Joaquin Basin, California, USA. Methane (2.8 × 10−7 to 3 × 10−2 cm3 STP/cm3) was detected in 27 of 30 groundwater samples. Using atmospheric noble gas signatures, the presence of oil-field water was identified in 3 samples, which had equilibrated with thermogenic hydrocarbons in the reservoir. Two (of the three) samples also had a shallow microbial methane component, acquired when produced water was deposited in a disposal pond at the surface. An additional 6 samples contained benzene and toluene, indicative of interaction with oil-field water; however, the noble gas signatures of these samples are not anomalous. Based on low tritium and 14C contents (≤ 0.3 TU and 0.87–6.9 pcm, respectively), the source of oil-field water is likely deep, which could include both anthropogenic and natural processes. Incorporating noble gas analytical techniques into the groundwater monitoring programme allows us to 1) differentiate between thermogenic and microbial hydrocarbon gas sources in instances when methane isotope data are unavailable, 2) identify the carrier phase of oil-field constituents in the aquifer (gas, oil-field water, or a combination), and 3) differentiate between leakage from a surface source (disposal ponds) and from the hydrocarbon reservoir (either along natural or anthropogenic pathways such as faulty wells)
Electrohydrodynamic jet printed conducting polymer for enhanced chemiresistive gas sensors dagger
No full textElectrohydrodynamic Jet Printing (EHD) enables the printing of sub-micron structures using a wide variety of materials and substrates, thus comparing favorably to many current additive manufacturing techniques. By using EHD to print polyaniline based chemiresistors, we demonstrate ammonia gas sensors reaching a detection sensitivity of 2.5% ppm−1 (limit of detection = 0.2 ppm) on glass, and 6.9% ppm−1, (limit of detection = 0.7 ppm) on flexible substrates. We quantitatively compare the results obtained from printed sensors to those prepared with conventional dropcasting, and find significant improvement. Further, we report our findings on the role of the dopant acid in the polymer structure and sensing, as well as the processability of polyaniline for EHD with the use of advanced characterization techniques. This work validates the use of EHD for printed sensors on flexible substrates, laying the groundwork for further research and development into rapid production of a host of miniaturized flexible polymer sensors
Pandemic-related pregnancy stress among pregnant women during the COVID-19 pandemic in Spain
No full textObjective
The aim was to develop and establish the psychometric properties of the Pandemic-Related Pregnancy Stress Scale (PREPS) in European Spanish speaking pregnant women in Spain.
Design
A cross section design using a non-random sample of 206 women completed the questionnaire during the first COVID-19 pandemic lockdown from April to June 2020 in Spain. Psychological, sociodemographic and obstetric factors and the new PREPS were collected.
Results
Bartlett's test of sphericity (χ2(105) = 580.36, p .77), and for F1 - Preparedness (α > .65), for F2 - Infection (α > 0.60) and for F3 - Positive appraisal (α > .55). The three factors exhibited good inter-item correlations, (F1 – Preparedness: .21; F2 – Infection: .23, and F3 – Positive Appraisal: .29). Convergent validity was examined through the Pearson's correlation coefficients of the PREPS with the Perceived Stress Scale (PSS) and the Prenatal Distress Questionnaire (PDQ). Correlation between PREPS total and PSS was high, and moderate with PDQ (p < .05).
Conclusion
The psychometric properties of the Spanish version of the PREPS make it a valuable psychological measure to assess pandemic-related stress among pregnant women
Dataset for "How to administer an antidote to Schrödinger’s cat"
No full textExperimental data gathered in laboratory, recorded by Single Photon Counting Modules
Tebipenem as an oral alternative for the treatment of typhoid caused by XDR Salmonella Typhi
No full textBackground
Antimicrobial therapy is essential for the treatment of enteric fever, the infection caused by Salmonella serovars Typhi and Paratyphi A. However, an increase in resistance to key antimicrobials and the emergence of MDR and XDR in Salmonella Typhi poses a major threat for efficacious outpatient treatments.
Objectives
We recently identified tebipenem, an oral carbapenem licensed for use for respiratory tract infections in Japan, as a potential alternative treatment for MDR/XDR Shigella spp. Here, we aimed to test the in vitro antibacterial efficacy of this drug against MDR and XDR typhoidal Salmonella.
Methods
We determined the in vitro activity of tebipenem in time–kill assays against a collection of non-XDR and XDR Salmonella Typhi and Salmonella Paratyphi A (non-XDR) isolated in Nepal and Bangladesh. We also tested the efficacy of tebipenem in combination with other antimicrobials.
Results
We found that both XDR and non-XDR Salmonella Typhi and Salmonella Paratyphi A are susceptible to tebipenem, exhibiting low MICs, and were killed within 8–24 h at 2–4×MIC. Additionally, tebipenem demonstrated synergy with two other antimicrobials and could efficiently induce bacterial killing.
Conclusions
Salmonella Paratyphi A and XDR Salmonella Typhi display in vitro susceptibility to the oral carbapenem tebipenem, while synergistic activity with other antimicrobials may limit the emergence of resistance. The broad-spectrum activity of this drug against MDR/XDR organisms renders tebipenem a good candidate for clinical trials
Supporting data for host regulation of the legume-rhizobia symbiosis
No full textAs documented in ReadMe fil
China, Europe and the Great Divergence: a restatement
No full textPeter Solar highlights some shortcomings of our treatment of government spending. However, correcting for these shortcomings using data rather than assumptions confirms our principal findings. GDP per capita in the leading region of China remained around the same level as in the leading region of Europe until the 18th century before declining substantially during the Qing dynasty. The Great Divergence thus began around 1700, earlier than originally suggested by the California School, but later than implied by earlier writers. The new data do not support Solar’s novel chronology with its Great Crossing, Great Convergence and Greater Divergence