58 research outputs found
Azotobacter chroococcum F8/2: a multitasking bacterial strain in sugar beet biopriming
This study assesses the effects of Azotobacter biopriming on the early development of sugar beet. Azotobacter chroococcum F8/2 was screened for plant growth promoting characteristics and biopriming effects were estimated through germination parameters and the structural changes of the root tissues. A. chroococcum F8/2 was characterized as a contributor to nitrogen, iron, and potassium availability, as well as a producer of auxin and 1-aminocyclopropane-1-carboxilic acid deaminase. Applied biopriming had reduced mean germination time by 34.44% and increased vigor I by 90.99% compared to control. Volatile blend comprised 47.67% ethanol, 32.01% 2-methyl-propanol, 17.32% 3-methyl-1-butanol, and a trace of 2,3-butanedione. Root micromorphological analysis of bioprimed sugar beet revealed a considerable increase in primary, secondary xylem area, and vessels size. Obtained results determine A. chroococcum F8/2 as a successful biopriming agent, and active participant in nutrient availability and hormonal status modulation affecting root vascular tissue. Ā© 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group
The effects of the āStompā herbicide application on the microbial prevalence in the soil.
Agricultural production has benefited a lot from herbicides; however, the use of herbicides caused
many environmental problems. Herbicide application can affect the biodiversity of an ecosystem by
killing non-target organisms. Microorganisms in the soil are important factors for plant growth; they
represent the biological factor of soil fertility. Herbicides can have a beneficial effect on the
development of some microorganisms and a negative on others, leading to depletion of microbial
diversity in soil. The objective of this work is to determine microbial activity in the soil and to isolate
herbicide-resistant bacteria after the use of the āStompā herbicide. Agar plate method was used for the
determination of microbial prevalence in the soil. The results showed an increase in the total number
of bacteria, ammonifiers, fungi, and actinomycetes. Nine isolates, mostly Gram-positive spore-
forming rods, showed an ability to grow in the mineral salt medium with different concentrations of
āStompā herbicide. Isolates G1/1 and G1/2, showed high level of tolerance at the initial pendimethalin
concentration of 25 mg/l. Those isolates have the potential to be used to decontaminate herbicide
affected ecosystems
Long-Term Optical Monitoring of Broad-Line AGNs (LoTerm AGN): Case Study of NGC 3516
Properties of the broad line region (BLR) in active galactic nuclei (AGNs) are commonly used to estimate the mass of the supermassive black hole (SMBH) that powers an AGN. However, the understanding of the physics behind the BLR remains incomplete. The AGNs exhibit strong optical variability, observed in the change of the profiles and fluxes of broad emission lines. Utilizing this variability provides an opportunity to constrain the physics of the BLR, and understand the interplay of the BLR with SMBH and surrounding regions. Here, we present the long-term monitoring campaign of a sample of the known broad-line AGNs (identified as LoTerm AGN). The aim of this study is to show the importance of sustained and dedicated campaigns that continually collect spectroscopic data of the known AGNs over extended timescales, providing unique insight into the origin and structure of the BLR. LoTerm AGN is a collaborative network of seven moderate-size telescopes equipped for spectroscopy. We focus on the recent spectral data of the known changing-look AGN, NGC 3516. Specifically, we examine the broad hydrogen Balmer Hα line observed in the period 2020–2023, demonstrating that this AGN remains active with the BLR signatures observed in the spectra. No significant change in the broad line profile of Hα line is observed during this recent period
Multiuser Cognitive Radio Networks: An Information Theoretic Perspective
Achievable rate regions and outer bounds are derived for three-user
interference channels where the transmitters cooperate in a unidirectional
manner via a noncausal message-sharing mechanism. The three-user channel
facilitates different ways of message-sharing between the primary and secondary
(or cognitive) transmitters. Three natural extensions of unidirectional
message-sharing from two users to three users are introduced: (i) Cumulative
message sharing; (ii) primary-only message sharing; and (iii) cognitive-only
message sharing. To emphasize the notion of interference management, channels
are classified based on different rate-splitting strategies at the
transmitters. Standard techniques, superposition coding and Gel'fand-Pinsker's
binning principle, are employed to derive an achievable rate region for each of
the cognitive interference channels. Simulation results for the Gaussian
channel case are presented; they enable visual comparison of the achievable
rate regions for different message-sharing schemes along with the outer bounds.
These results also provide useful insights into the effect of rate-splitting at
the transmitters, which aids in better interference management at the
receivers.Comment: 50 pages, 15 figures, submitted to IEEE Transactions on Information
Theor
Development of a 3D workspace Shoulder Assessment Tool Incorporating Electromyography and an Inertial Measurement Unit - A preliminary study
Traditional shoulder Range of Movement (ROM) measurement tools suffer from inaccuracy or from long experimental set-up times. Recently, it has been demonstrated that relatively low-cost wearable inertial measurement unit (IMU) sensors can overcome many of the limitations of traditional motion tracking systems.
The aim of this study is to develop and evaluate a single IMU combined with an Electromyography (EMG) sensor to monitor the 3D reachable workspace with simultaneous measurement of deltoid muscle activity across the shoulder ROM. Six volunteer subjects with healthy shoulders and one participant with a āfrozenā shoulder were recruited to the study. Arm movement in 3D space was plotted in spherical coordinates while the relative EMG intensity of any arm position is presented graphically.
The results showed that there was an average ROM surface area of 27291Ā±538 deg2 among all six healthy individuals and a ROM surface area of 13571Ā±308 deg2 for the subject with frozen shoulder. All three sections of the deltoid show greater EMG activity at higher elevation angles.
Using such tools enables individuals, surgeons and physiotherapists to measure the maximum envelope of motion in conjunction with muscle activity in order to provide an objective assessment of shoulder performance in the voluntary 3D workspace
Targeted plant improvement through genome editing: from laboratory to field
This review illustrates how far we have come since the emergence of GE technologies and how they could be applied to obtain superior and sustainable crop production. The main challenges of today's agriculture are maintaining and raising productivity, reducing its negative impact on the environment, and adapting to climate change. Efficient plant breeding can generate elite varieties that will rapidly replace obsolete ones and address ongoing challenges in an efficient and sustainable manner. Site-specific genome editing in plants is a rapidly evolving field with tangible results. The technology is equipped with a powerful toolbox of molecular scissors to cut DNA at a pre-determined site with different efficiencies for designing an approach that best suits the objectives of each plant breeding strategy. Genome editing (GE) not only revolutionizes plant biology, but provides the means to solve challenges related to plant architecture, food security, nutrient content, adaptation to the environment, resistance to diseases and production of plant-based materials. This review illustrates how far we have come since the emergence of these technologies and how these technologies could be applied to obtain superior, safe and sustainable crop production. Synergies of genome editing with other technological platforms that are gaining significance in plants lead to an exciting new, post-genomic era for plant research and production. In previous months, we have seen what global changes might arise from one new virus, reminding us of what drastic effects such events could have on food production. This demonstrates how important science, technology, and tools are to meet the current time and the future. Plant GE can make a real difference to future sustainable food production to the benefit of both mankind and our environment.European Cooperation in Science and Technology (COST) CA18111info:eu-repo/semantics/publishedVersio
Wireless distributed functional electrical stimulation system
<p>Abstract</p> <p>Background</p> <p>The control of movement in humans is hierarchical and distributed and uses feedback. An assistive system could be best integrated into the therapy of a human with a central nervous system lesion if the system is controlled in a similar manner. Here, we present a novel wireless architecture and routing protocol for a distributed functional electrical stimulation system that enables control of movement.</p> <p>Methods</p> <p>The new system comprises a set of miniature battery-powered devices with stimulating and sensing functionality mounted on the body of the subject. The devices communicate wirelessly with one coordinator device, which is connected to a host computer. The control algorithm runs on the computer in open- or closed-loop form. A prototype of the system was designed using commercial, off-the-shelf components. The propagation characteristics of electromagnetic waves and the distributed nature of the system were considered during the development of a two-hop routing protocol, which was implemented in the prototypeās software.</p> <p>Results</p> <p>The outcomes of this research include a novel system architecture and routing protocol and a functional prototype based on commercial, off-the-shelf components. A proof-of-concept study was performed on a hemiplegic subject with paresis of the right arm. The subject was tasked with generating a fully functional palmar grasp (closing of the fingers). One node was used to provide this movement, while a second node controlled the activation of extensor muscles to eliminate undesired wrist flexion. The system was tested with the open- and closed-loop control algorithms.</p> <p>Conclusions</p> <p>The system fulfilled technical and application requirements. The novel communication protocol enabled reliable real-time use of the system in both closed- and open-loop forms. The testing on a patient showed that the multi-node system could operate effectively to generate functional movement.</p
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