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Differential physio-biochemical and metabolic responses of peanut (Arachis hypogaea L.) under multiple abiotic stress conditions
Get PDFThe frequency and severity of extreme climatic conditions such as drought, salinity, cold, and heat are increasing due to climate change. Moreover, in the field, plants are affected by multiple abiotic stresses simultaneously or sequentially. Thus, it is imperative to compare the effects of stress combinations on crop plants relative to individual stresses. This study investigated the differential regulation of physio-biochemical and metabolomics parameters in peanut (Arachis hypogaea L.) under individual (salt, drought, cold, and heat) and combined stress treatments using multivariate correlation analysis. The results showed that combined heat, salt, and drought stress compounds the stress effect of individual stresses. Combined stresses that included heat had the highest electrolyte leakage and lowest relative water content. Lipid peroxidation and chlorophyll contents did not significantly change under combined stresses. Biochemical parameters, such as free amino acids, polyphenol, starch, and sugars, significantly changed under combined stresses compared to individual stresses. Free amino acids increased under combined stresses that included heat; starch, sugars, and polyphenols increased under combined stresses that included drought; proline concentration increased under combined stresses that included salt. Metabolomics data that were obtained under different individual and combined stresses can be used to identify molecular phenotypes that are involved in the acclimation response of plants under changing abiotic stress conditions. Peanut metabolomics identified 160 metabolites, including amino acids, sugars, sugar alcohols, organic acids, fatty acids, sugar acids, and other organic compounds. Pathway enrichment analysis revealed that abiotic stresses significantly affected amino acid, amino sugar, and sugar metabolism. The stress treatments affected the metabolites that were associated with the tricarboxylic acid (TCA) and urea cycles and associated amino acid biosynthesis pathway intermediates. Principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), and heatmap analysis identified potential marker metabolites (pinitol, malic acid, and xylopyranose) that were associated with abiotic stress combinations, which could be used in breeding efforts to develop peanut cultivars that are resilient to climate change. The study will also facilitate researchers to explore different stress indicators to identify resistant cultivars for future crop improvement programs
A New Handover Management Model for Two-Tier 5G Mobile Networks
Get PDFThere has been an exponential rise in mobile data traffic in recent times due to the increasing popularity of portable devices like tablets, smartphones, and laptops. The rapid rise in the use of these portable devices has put extreme stress on the network service providers while forcing telecommunication engineers to look for innovative solutions to meet the increased demand. One solution to the problem is the emergence of fifth-generation (5G) wireless communication, which can address the challenges by offering very broad wireless area capacity and potential cut-power consumption. The application of small cells is the fundamental mechanism for the 5G technology. The use of small cells can enhance the facility for higher capacity and reuse. However, it must be noted that small cells deployment will lead to frequent handovers of mobile nodes. Considering the importance of small cells in 5G, this paper aims to examine a new resource management scheme that can work to minimize the rate of handovers for mobile phones through careful resources allocation in a two-tier network. Therefore, the resource management problem has been formulated as an optimization issue that we aim to overcome through an optimal solution. To find a solution to the existing problem of frequent handovers, a heuristic approach has been used. This solution is then evaluated and validated through simulation and testing, during which the performance was noted to improve by 12% in the context of handover costs. Therefore, this model has been observed to be more efficient as compared to the existing model
J-Edited diffusional proton nuclear magnetic resonance spectroscopic measurement of glycoprotein and supramolecular phospholipid biomarkers of inflammation in human serum
No full textProton nuclear magnetic resonance (NMR) N-acetyl signals (Glyc) from glycoproteins and supramolecular phospholipids composite peak (SPC) from phospholipid quaternary nitrogen methyls in subcompartments of lipoprotein particles) can give important systemic metabolic information, but their absolute quantification is compromised by overlap with interfering resonances from lipoprotein lipids themselves. We present a J-Edited DIffusional (JEDI) proton NMR spectroscopic approach to selectively augment signals from the inflammatory marker peaks Glyc and SPCs in blood serum NMR spectra, which enables direct integration of peaks associated with molecules found in specific compartments. We explore a range of pulse sequences that allow editing based on peak J-modulation, translational diffusion, and T2 relaxation time and validate them for untreated blood serum samples from SARS-CoV-2 infected patients (n = 116) as well as samples from healthy controls and pregnant women with physiological inflammation and hyperlipidemia (n = 631). The data show that JEDI is an improved approach to selectively investigate inflammatory signals in serum and may have widespread diagnostic applicability to disease states associated with systemic inflammation
Spinal pain in childhood: prevalence, trajectories, and diagnoses in children 6 to 17 years of age
No full textThis study aimed to investigate the trajectories of spinal pain frequency from 6 to 17 years of age and describe the prevalence and frequency of spinal pain and related diagnoses in children following different pain trajectories. First through fifth-grade students from 13 primary schools were followed for 5.5 years. Occurrences of spinal pain were reported weekly via text messages. Children reporting spinal pain were physically evaluated and classified using International Classification of Disease criteria. Trajectories of spinal pain frequency were modeled from age 6 to 17 years with latent class growth analysis. We included data from 1556 children (52.4% female, mean (SD) baseline age = 9.1 (1.9) years) and identified 10,554 weeks of spinal pain in 329,756 weeks of observation. Sixty-three percent of children reported one or more occurrences of spinal pain. We identified five trajectories of spinal pain frequency. Half the children (49.8%) were classified as members of a “no pain” trajectory. The remaining children followed “rare” (27.9%), “rare, increasing” (14.5%), “moderate, increasing” (6.5%), or “early-onset, decreasing” (1.3%) spinal pain trajectories. The most common diagnoses in all trajectory groups were non-specific (e.g., “back pain”). Tissue-specific diagnoses (e.g., muscle strain) were less common and pathologies (e.g., fracture) were rare.
Conclusion: From childhood through adolescence, spinal pain was common and followed heterogeneous courses comprising stable, increasing, and early-onset trajectories. These findings accord with recommendations from adult back pain guidelines that most children with spinal pain can be reassured that they do not have a serious disease and encouraged to stay active
Association of common zoonotic pathogens with concentrated animal feeding operations
Get PDFAnimal farming has intensified significantly in recent decades, with the emergence of concentrated animal feeding operations (CAFOs) in industrialized nations. The congregation of susceptible animals in CAFOs can lead to heavy environmental contamination with pathogens, promoting the emergence of hyper-transmissible, and virulent pathogens. As a result, CAFOs have been associated with emergence of highly pathogenic avian influenza viruses, hepatitis E virus, Escherichia coli O157:H7, Streptococcus suis, livestock-associated methicillin-resistant Staphylococcus aureus, and Cryptosporidium parvum in farm animals. This has led to increased transmission of zoonotic pathogens in humans and changes in disease patterns in general communities. They are exemplified by the common occurrence of outbreaks of illnesses through direct and indirect contact with farm animals, and wide occurrence of similar serotypes or subtypes in both humans and farm animals in industrialized nations. Therefore, control measures should be developed to slow down the dispersal of zoonotic pathogens associated with CAFOs and prevent the emergence of new pathogens of epidemic and pandemic potential
Integrated reporting quality and corporate tax avoidance practices in South Africa’s listed companies
No full textPurpose
This study aims to examine the relationship between integrated reporting (IR) quality and corporate tax avoidance (CTA). IR is an emerging reporting mechanism, while CTA practices are considered a hindrance to inclusive and sustainable growth. The study also assesses the moderating role of firm complexity on the IR-CTA relationship. Additionally, this study also envisages that CTA practices are not static. Hence, it also analyses the IR-CTA relationship across different intensity levels of CTA practices. The study focusses on listed companies in South Africa, the only country that has mandated IR practice so far.
Design/methodology/approach
Ordinary least square and quantile regressions are used to analyse archival and content analysis data for firms listed on the Johannesburg Stock Exchange from 2011 to 2017.
Findings
This study finds that IR quality negatively associates firms CTA practices. It further concludes that although firms’ transparency level increases due to IR quality, firm complexity reduces the significant negative relationship between IR and CTA practices. The findings also indicate that the IR-CTA relationship is not constant but instead differs across the CTA quantiles. At aggressive levels of CTA, no relationship is established between IR quality and firms’ CTA practices.
Practical implications
The findings provide a useful and more detailed description of the relationship between information quality and CTA practice, focussing on IR, an emerging reporting mechanism that is considered innovative and transparent.
Social implications
Considering the IR-CTA relationship found in this study, IR quality implementation may indirectly contribute to attaining sustainable development goals by reducing CTA practices.
Originality/value
This study examines the relationship between reporting quality and firms’ CTA practices from the perspectives of an emerging reporting mechanism, with a focus on South Africa, the only country that has mandated IR practice. Furthermore, the distributional mean effects of IR quality on firms’ CTA practices explored in this study extend beyond the usual IR-CTA relationship
Network analyses of internet gaming disorder symptoms and their links with different types of motivation
Get PDFThe study used regularized partial correlation network analysis (EBICglasso) to examine the structure of DSM-5 internet gaming disorder (IGD) symptoms (network 1); and the associations of the IGD symptoms in the network with different types of motivation as defined in the self-determination theory i.e., intrinsic motivation (engaging in an activity for something unrelated to the activity), identified regulation (engaging in the activity because it aligns with one’s values and/or goals), external regulation (engagement in activity being driven by external rewards and/or approval), and amotivation (engaging in an activity without often understanding why) (network 2). Participants were 968 adults from the general community. They completed self-rating questionnaires covering IGD symptoms and different types of motivation. The findings for network 1 showed mostly positive connections between the symptoms within the IGD network. The most central symptom was loss of control, followed by continuation, withdrawal symptoms, and tolerance. In general, these symptoms were more strongly connected with each other than with the rest of the IGD symptoms. The findings for network 2 showed that the different types of motivation were connected differently with the different IGD symptoms. For instance, the likeliest motivation for the preoccupation and escape symptoms is intrinsic motivation, and for negative consequences, it is low identified regulation. Overall, the findings showed a novel understanding of the structure of the IGD symptoms, and the motivations underlying them. The clinical implications of the findings for assessment and treatment of IGD are discussed
Biomechanical comparison of a notched head locking t-plate and a straight locking compression plate in a juxta-articular fracture model
Get PDFObjective:
To investigate the biomechanical properties of a 2.0 mm notched head T-plate (NHTP) and 8-hole 2.0 mm straight locking compression plate (LCP), in a simple transverse model with a short distal fragment, applied with various screw configurations that alter the working length of the plate.
Methods:
Two different screw configurations were compared for the NHTP and LCP, modelling short (configuration 1) and long working length (configuration 2) across two different distal fragments lengths (13 mm and 9 mm). Constructs were tested in three planes of non-destructive four point bending and torsion. Construct stiffness and plate strain was compared between screw configurations within and between each plate.
Results:
In the first investigation (13 mm fragment), the LCP was stiffer than the NHTP in all three planes of bending and in torsion (P<0.05). The NHTP had greater strain during compression bending and torsion at all ROI (P<0.0005). In the second investigation (9 mm fragment), the LCP was significantly stiffer than the NHTP in all three planes of bending (P<0.05) for both screw configurations. The NHTP was stiffer than the LCP in torsion (P<0.05) for both screw configurations. The NHTP had greater strain than the LCP during compression bending at three ROI (P<0.0005). The LCP had greater strain than the NHTP during torsion at three ROI (P<0.0005). In both investigations the short working length was stiffer in all three planes of bending and in torsion (P<0.05) than the longer working length for both plates. The long working length produced greater plate strain than the short working length at most ROI.
Conclusions:
The LCP with two screws in a short fragment, was significantly stiffer and had lower plate strain, in most planes of testing, than NHTP with three locking screws in the short fragment. Extending the working length of each construct by omitting locking screws in the long fragment adjacent to the fracture line significantly reduced construct stiffness and increased plate strain
Performance analysis of a FSO link considering different atmospheric turbulence
No full textFree space optical (FSO) technology is a quick-to-deploy and economical way of getting access to the fiber optic network. FSO technology not only offers fiber-quality connections, but it also offers the sector’s cheapest transmission capacity. FSO systems complement legacy network commitments and function in harmony with any protocol, saving significant up-front investments as a completely protocol-independent broadband gateway. An FSO link may be purchased and deployed at a fraction of the cost of installing fiber cable and for roughly half the cost of equivalent microwave/RF wireless systems. With exception of RF wireless technologies, FSO does not need the purchase of expensive spectrum licenses or the fulfillment of additional regulatory criteria. The purpose of this study is to examine the performance of FSO-based optical access networks. Analysis of the performance in detail, with a focus on BER is also described
Potential role of curcumin for the treatment of major depressive disorder
Get PDFCurcumin is the major biologically active polyphenolic constituent in the turmeric plant (Curcuma longa) that has been shown to have antioxidant, anti-inflammatory, neuroprotective, anticancer, antimicrobial, and cardioprotective effects. Interest in curcumin as a treatment for mental health conditions has increased and there is an expanding body of preclinical and clinical research examining its antidepressant and anxiolytic effects. In this narrative review, human trials investigating the effects of curcumin for the treatment of depression or depressive symptoms are summarised. Using findings from in vitro, animal, and human trials, possible biological mechanisms associated with the antidepressant effects of curcumin are also explored. To increase the understanding of curcumin for the treatment of depression, directions for future research are proposed