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The \u3cem\u3eRAD6\u3c/em\u3e-like Ubiquitin Conjugase Gene \u3cem\u3eOsUBC7\u3c/em\u3e Has a Positive Role in the Early Cold Stress Tolerance Response of Rice
No full textBackground/Objectives: Cold stress poses a significant threat to Asian rice cultivation, disrupting important physiological processes crucial for seedling establishment and overall plant growth. It is, thus, crucial to elucidate genetic pathways involved in cold stress tolerance response mechanisms. Methods: We mapped OsUBC7, a Radiation-sensitive 6 (RAD6)-type homolog of rice, to a low-temperature seedling survivability (LTSS) QTL and used genomics, molecular genetics, and physiological assays to assess its role in plant resilience against low-temperature stress. Results: OsUBC7 is cold responsive and has higher expression levels in cold-tolerant japonica than cold-sensitive indica. Overexpression of OsUBC7 enhances LTSS of indica and freezing tolerance of Arabidopsis, increases levels of soluble sugars and chlorophyll A, boosts leaf development after cold exposure, and increases leaf cell numbers and plants size, but it does not affect membrane stability after cold stress exposure. Additionally, OsUBC7 has a positive role for germinability in the presence of salt and for flowering and yield-related traits. The OsUBC7 protein physically interacts with the developmental stage-specific and histone-modifying E3 ligases OsRFPH2-12 and OsHUB1/2, respectively, and potential target genes such as cell cycle dependent kinases were identified. Conclusions: OsUBC7 might contribute to cold resilience by regulating sugar metabolism to provide energy for promoting cellular homeostasis restoration after cold stress exposure via new cell growth, particularly in leaf cells crucial for photosynthesis and metabolic activity, possibly by interacting with cell cycle regulating proteins. Overall, the present study suggests that OsUBC7 may be involved in plant development, reproduction, and stress adaptation, and contributes to a deeper understanding of rice plant cold stress tolerance response mechanisms. OsUBC7 may be a promising candidate for improving crop productivity and resilience to stressful environments
Building Diversity Into the Philosophy and Methodology of Economics with Stratification Economics
Get PDFMainstream economics ignores who produces it and what it is about because its average man, Homo economicus ontological entry-point obscures social differences between people. Philosophy and Methodology of Economics that assumes this ontological entry point generally limits itself to epistemological analysis, and this means it fails to make diversity a fundamental concern. Taking diversity seriously entails being clear about one\u27s ontological assumptions, and this requires being clear about the normative scope of one\u27s analysis. This calls for giving up a value-neutral methodological reasoning and adopting a value-explicit methodological posture. To illustrate, we describe how Stratification economics with its social groups ontological entry-point shows societies are structured around hierarchical social group rankings that differentiate people according to their social identity status. We explain this in both micro-level and macro-level terms, show that together they produce systems of inclusion and exclusion, and argue that this raises issues of equality and justice
Elucidating the Impact of Common Stormwater Pollutants on Antibiotic Resistance: The Role Of Heavy Metals, Nutrients, and Salts
No full textAntibiotic resistance poses a significant global health threat, and the urban water cycle presents an opportunity to augment or limit the spread of antibiotic resistance. In particular, stormwater runoff has recently been revealed as a key conduit for antibiotic-resistant bacteria (ARB). The specific role of stormwater pollutants, however, on antibiotic resistance has not been isolated. Understanding the impact of specific pollutants common to stormwater could help optimize design and operation of stormwater systems for management of antibiotic resistance. The objective of this research was to establish the potential contributions of common stormwater pollutants to antibiotic resistance proliferation. Lab-scale stormwater microcosms were amended with either heavy metals, nutrients, or salts, and then ARB and antibiotic resistance gene (ARG) concentrations were quantified over a seven-day period. The microcosm experiments revealed that heavy metals (5–1000 μg L−1) on average significantly increased (p \u3c 0.05) ARGs and ARB concentrations 0.30 log and 0.96 log, respectively, and the effects were dependent on the concentration of the metal. Total bacterial counts increased by 174% in nutrient-amended microcosms, while ARG levels remained statistically unchanged (p \u3e 0.05). Salts, a common pollutant in colder climates, exhibited no impact. Moving forward, targeted interventions focusing on heavy metal removal, alongside careful stormwater treatment design, could offer promising avenues for addressing antibiotic resistance dissemination in urban environments
Response Surface Methodology for Evaluating Electrocoagulation Treatment of Bath and Laundry Greywater
No full textElectrocoagulation (EC) has potential for on-site water reuse; however, it has yet to be systematically evaluated for greywater treatment. We used rigorous definitive screening design (DSD) and response surface methodology (RSM) statistical models to evaluate the influence of EC operating parameters, including charge loading (a function of time and current density) and solution temperature on the removal of biochemical oxygen demand (BOD5), total suspended solids (TSS), turbidity, and E. coli in synthetic bath and laundry greywater. Aluminum (Al) and iron (Fe) electrode combinations were tested. The Al anode combinations (AlFe or AlAl) outperformed electrode combinations using Fe as the anode for contaminant removal. Increasing EC charge loading did not consistently improve contaminant removal, such that the lower range of charge loadings tested were recommended (72–432 C L−1). The conditions offering the best holistic contaminant removal (AlFe, 20 °C) removed 51.8 % BOD5, 83.7 % TSS, and 74.6 % turbidity in bath water. Under these same operating conditions, 19.1 % BOD5, 75.5 % TSS, and 82.6 % turbidity removal were achieved in laundry water. For E. coli, a maximum of 5.5 log reduction was observed in bathwater and ≥ 6.1 log reduction was observed in laundry water. The NSF/ANSI 350–2020 standards for TSS and E. coli effluent targets were achieved using the best performing EC operating conditions in bath and laundry water, respectively. However, the BOD5 and turbidity effluent standards were not achieved. Multiple regression equations were developed and visualized using contour and surface response plots to facilitate co-optimization of operating parameters
Is More Always Better? An Experimental Examination of the Effects of Feedback Frequency, Narcissistic Oversensitivity, and Growth Mindset on Performance Accuracy
No full textThe provision of more frequent feedback to employees is increasing, although prior research has found mixed results as to the effect of increased feedback frequency on employee performance. Narcissism research identifies narcissistic oversensitivity as a key narcissistic subdimension that may result in particularly strong responses to performance feedback. We predict and find in an experiment that increased performance feedback frequency has a more negative impact on the performance accuracy of individuals with higher levels of narcissistic oversensitivity and that this negative interactive effect of feedback frequency and narcissistic oversensitivity is mitigated by the priming of a growth mindset. These results should be of practical interest to firms as they design their management control systems to improve employee performance, considering the variation in narcissistic oversensitivity among their employees. These results also contribute to recent accounting research on the effects of feedback frequency and employee mindsets
Leveraging Science to Accelerate Reading Achievement in a Summer Learning Program for Low-Income Children
No full textThis study examined the effects of a 4-week summer reading program for primary-grade children who read below grade level given an hour of integrated literacy and science instruction following 90 min of targeted reading instruction. Children\u27s reading achievement, science knowledge, and science attitudes were compared pre- and post-program, and their reading gain was compared with that of children who attended the program in summers when the integrated instruction was not offered. Students in each condition showed significantly greater reading achievement at posttest each summer. Integrated literacy and science students showed significantly greater conceptual science knowledge at posttest, comparable pretest and posttest science attitudes, and significantly greater reading gain relative to students who did not participate in the integrated instruction on the Gates-MacGinitie Reading Test-4. The findings demonstrate that integrated literacy and science instruction can accelerate primary-grade students\u27 reading achievement in summer learning programs while developing their conceptual science knowledge
Lung Uptake of Two SPECT Markers Identifies Sensitivity to Hyperoxia-Induced Acute Respiratory Distress Syndrome in Rats
No full textIntroduction:
Exposure of adult rats to hyperoxia is a well-established model of human Acute Respiratory Distress Syndrome (ARDS). Although rats exposed to 100% O2 display clinical evidence of lung injury after ∼40 h and death by 72 h, rats exposed to 60% O2 for up to 7 days show little sign of injury. However, when subsequently exposed to hyperoxia, these pre-exposed rats become more susceptible to ARDS. The objective of this study is to evaluate the ability of imaging biomarkers to track this hyperoxia susceptibility and to elucidate underlying mechanisms.
Methods:
Sprague-Dawley rats were exposed to either room air (normoxia), \u3e95% O2 for 24 h (hyperoxia), 60% O2 for 7 days (H-S), or H-S followed by 24 h of hyperoxia (H-S+24). Following i.v. injection of 99mTcduramycin (marker of cell death) and/or 99mTc-hexamethylpropelyneamine oxime (99mTc-HMPAO, marker of lung tissue redox status), in vivo scintigraphy images were acquired and lung uptake of these biomarkers was determined from the images.
Results:
99mTc-HMPAO uptake was 84% greater in hyperoxic rats compared to normoxic controls. Uptake in H-S rats was 34% higher than normoxics, but with no change with subsequent exposure to hyperoxia (HS+24). 99mTc-duramycin uptake was 40% greater in hyperoxic rats than normoxics. Uptake in H-S rats was not different from normoxics but increased by 160% with H-S+24 in conjunction with enhanced hyperoxia susceptibility. 99mTc-HMPAO and 99mTc-duramycin uptake correlated with expression of 3- nitrotyrosine (oxidative stress) and cleaved-caspase 3 (cell death) measures acquired independently.
Discussion:
Overall, these results suggest the potential utility of 99mTc-HMPAO and 99mTc-duramycin imaging for identifying those hosts that are more, or less, susceptible to progression to severe ARDS at a time of mild symptoms of lung injury
Identification of Diverse Bacteriophages Associated with Bees and Hoverflies
No full textBacteriophages are the most numerous, ubiquitous, and diverse biological entities on the planet. Prior studies have identified bacteriophages associated with pathogenic and commensal microbiota of honeybees. In this study we expand on what is known about bacteriophages from the lineages Caudoviricetes, Inoviridae, and Microviridae, which are associated with honeybees (Apidae, Apis mellifera), solitary bees of the genus Nomia (Halictidae, Nomia), and hoverflies (Syrphidae). The complete genomes of seven caudoviruses, seven inoviruses, and 288 microviruses were assembled from honeybees (n = 286) and hoverflies in Arizona (n = 2). We used bacterial host predictive software and sequence read mapping programs to infer the commensal and transient bacterial hosts of pollinating insects. Lastly, this study explores the phylogenetic relationships of microviruses sampled from bees, opportunistically sampled pollinating insects such as hoverflies, and blackflies
A Novel Diastolic Doppler Index Less Affected by Aortic Arch Anomalies Co-existing with Coarctation
No full textSeverity assessment for coarctation of the aorta (CoA) is challenging due to concomitant morphological anomalies (complex CoA) and inaccurate Doppler-based indices. Promising diagnostic performance has been reported for the continuous flow pressure gradient (CFPG), but it has not been studied in complex CoA. Our objective was to characterize the effect of complex CoA and associated hemodynamics on CFPG in a clinical cohort. Retrospective analysis identified discrete juxtaductal (n = 25) and complex CoA (n = 43; transverse arch and/or isthmus hypoplasia) patients with arm-leg systolic blood pressure gradients (BPG) within 24 h of echocardiography for comparison to BPG by conventional Doppler indices (simplified Bernoulli equation and modified forms correcting for proximal kinetic energy and/or recovered pressure). Results were interpreted using the current CoA guideline (BPG ≥ 20 mmHg) to compare diagnostic performance indicators including receiver operating characteristic curves, sensitivity, specificity, and diagnostic accuracy, among others. Echocardiography Z-scored aortic diameters were applied with computational simulations from a preclinical CoA model to understand aspects of the CFPG driving performance differences. Diagnostic performance was substantially reduced from discrete to complex CoA for conventional Doppler indices calculated from patient data, and by hypoplasia and/or long segment stenosis in simulations. In contrast, diagnostic indicators for the CFPG only modestly dropped for complex vs discrete CoA. Simulations revealed differences in performance due to inclusion of the Doppler velocity index and diastolic pressure half-time in the CFPG calculation. CFPG is less affected by aortic arch anomalies co-existing with CoA when compared to conventional Doppler indices