137 research outputs found
Comparing the rate of weapon and ornament diversification
In some species in one sex, generally males, ornaments evolve to attract females and/or sexually selected weapons evolve as a response to intrasexual competition for mating opportunities. A key prediction of classic Darwin/Fisher/Lande sexual selection theory is that sexually selected ornaments should evolve faster than sexually selected weapons. As male ornaments and female preferences for particular ornamental traits coevolve, selection occurs in both males and females and a positive feedback loop potentially enhancing the rate of trait evolution can develop under the Fisher process (Fisherian runaway selection)In this thesis I measure the rate of trait evolution of many examples of weapons and ornaments to test this at a macroevolutionary scale. . I assembled data on weapon and ornament traits from 22 diverse animal taxa. Pairs of weapon and ornament datasets comprising closely related taxa were formed to control factors such as generation time that may influence the different rates between traits. Trait values were standardised and the rates were compared using recently developed phylogenetic analyses under both Brownian motion and Ornstein-Uhlenbeck evolutionary models. I found strong evidence under both models that ornaments have consistently evolved faster than weapons. This suggests that Fisherian runaway processes have broad influence on the evolution of sexually selected ornaments at macroevolutionary scales across diverse taxa
English Language Testing for Citizenship
The proposed changes to citizenship requirements in Australia have an increased focus on English language competency and on ‘Australian’ values. The dominance of the English language on the global stage can reinforce the hegemonic nature of the English language, which is becoming increasingly embedded in the image of an Australian citizen. This raises questions on what is motivating the centrality of English language testing for citizenship, and how these shape conceptions of Australian identity. This research is a thematic content analysis of media releases from newspapers, government statements and other grey materials on the recent changes to Australia’s citizenship requirements, particularly English language testing. The research found that English language testing can be seen as a form of cultural hegemony, which is shaped by a discourse of social integration and border security. Implications for understanding diversity and working with diverse language groups are explored in light of the English language testing and citizenship discourses in Australia
Students With Emotional–Behavioral Disorders as Cross-Age Tutors: A Synthesis of the Literature
The purpose of this quantitative synthesis was to evaluate the effectiveness and related outcomes of the cross-age tutoring model when students with or at risk for emotional–behavioral disorders (EBD) serve as tutors. Research questions were posed to identify the shared and unique components (e.g., dosage, tutor training) of the cross-age tutoring model; the extent to which students with EBD can effectively serve as cross-age tutors (i.e., fidelity of implementation and tutees’ improvement); the extent to which the model was effective in promoting desired academic and/or social–emotional–behavioral outcomes for tutees and tutors with EBD; the generalization, maintenance, and social validity of the effects; and the overall methodological quality and rigor of the included studies. Findings showed common training and instructional components across interventions and that tutors with EBD can implement cross-age tutoring procedures with fidelity. The cross-age model was shown to be effective in promoting academic and social–behavioral skills for the tutees as well as the tutors. Evidence for effectiveness in improving self-concept and attitude of the tutor with EBD was inconsistent. Implications and future research considerations are discussed
2022 Lesson Plan | The Play Is the Thing
The most important part of studying Shakespeare is infusing meaning into the text. These activities will help you get Shakespeare on its feet and remove Shakes fear from your students.https://digitalcommons.jsu.edu/shakespeare_proj/1016/thumbnail.jp
Ces1d deficiency protects against high-sucrose diet-induced hepatic triacylglycerol accumulation
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Triacylglycerol accumulation in the liver is a hallmark of NAFLD. Metabolic studies have confirmed that increased hepatic de novo lipogenesis (DNL) in humans contributes to fat accumulation in the liver and to NAFLD progression. Mice deficient in carboxylesterase (Ces)1d expression are protected from high-fat diet-induced hepatic steatosis. To investigate whether loss of Ces1d can also mitigate steatosis induced by over-activated DNL, WT and Ces1d-deficient mice were fed a lipogenic high-sucrose diet (HSD). We found that Ces1d-deficient mice were protected from HSD-induced hepatic lipid accumulation. Mechanistically, Ces1d deficiency leads to activation of AMP-activated protein kinase and inhibitory phosphorylation of acetyl-CoA carboxylase. Together with our previous demonstration that Ces1d deficiency attenuated high-fat diet-induced steatosis, this study suggests that inhibition of CES1 (the human ortholog of Ces1d) might represent a novel pharmacological target for prevention and treatment of NAFLD.Fil: Lian, Jihong. University of Alberta; CanadáFil: Watts, Russell. University of Alberta; CanadáFil: Quiroga, Ariel Dario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Fisiología Experimental. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Fisiología Experimental; ArgentinaFil: Beggs, Megan R.. University of Alberta; CanadáFil: Alexander, R. Todd. University of Alberta; CanadáFil: Lehner, Richard. University of Alberta; Canad
The structural basis of bacterial manganese import
肺炎球菌が細胞内にマンガンイオンを取り込むしくみ --膜輸送体PsaBCの立体構造の解明--. 京都大学プレスリリース. 2021-09-15.Metal ions are essential for all forms of life. In prokaryotes, ATP-binding cassette (ABC) permeases serve as the primary import pathway for many micronutrients including the first-row transition metal manganese. However, the structural features of ionic metal transporting ABC permeases have remained undefined. Here, we present the crystal structure of the manganese transporter PsaBC from Streptococcus pneumoniae in an open-inward conformation. The type II transporter has a tightly closed transmembrane channel due to “extracellular gating” residues that prevent water permeation or ion reflux. Below these residues, the channel contains a hitherto unreported metal coordination site, which is essential for manganese translocation. Mutagenesis of the extracellular gate perturbs manganese uptake, while coordination site mutagenesis abolishes import. These structural features are highly conserved in metal-specific ABC transporters and are represented throughout the kingdoms of life. Collectively, our results define the structure of PsaBC and reveal the features required for divalent cation transport
The Student Movement Volume 106 Issue 11: And The Winner Is...: Andrews Talent Take Center Stage
HUMANS
Andrews Mission Trip to Honduras, Interviewed by: Lauren Kim
Rollin\u27 Through Life, Alexandria Dunham
Senior Spotlight: Noelle Millner, Interviewed by: Irina Gagiu
ARTS & ENTERTAINMENT
Creative Spotlight: Genevieve Prouty, Interviewed by: Megan Napod
Encanto : Disney\u27s Handling of Latinx Culture, Kaela McFadden
STREAM IT or SKIP IT: Everything I Watched Over Christmas Break, Solana Campbell
NEWS
A Day of Service. A Day of Strife. A Day to Honor Martin Luther King Jr., Chris Ngugi
A Show to Remember, an AU Talent Show Story, Chris Ngugi
Quarantining on Campus: Spring Semester 2022, Abigail Lee
IDEAS
Stand Up and Lear, Angelina Nesmith
The Significance of Symmetry, Alexander Navarro
What is the COVID Endgame?. Shania Watts
PULSE
Feeding Hungry Students, Karenna Lee
New Year, New Habits, Wambui Karanja
Winter Driving, Alannah Tjhatra
THE LAST WORD
Namaste, Alyssa Henriquezhttps://digitalcommons.andrews.edu/sm-106/1010/thumbnail.jp
Screening of predicted synergistic multi-target therapies in glioblastoma identifies new treatment strategies
SOD2 Deficiency in Cardiomyocytes Defines Defective Mitochondrial Bioenergetics as a Cause of Lethal Dilated Cardiomyopathy
Electrophilic aldehyde (4-hydroxynonenal; 4-HNE), formed after lipid peroxidation, is a mediator of mitochondrial dysfunction and implicated in both the pathogenesis and the progression of cardiovascular disease. Manganese superoxide dismutase (MnSOD), a nuclear-encoded antioxidant enzyme, catalyzes the dismutation of superoxide radicals (O2•-) in mitochondria. To study the role of MnSOD in the myocardium, we generated a cardiomyocyte-specific SOD2 (SOD2Δ) deficient mouse strain. Unlike global SOD2 knockout mice, SOD2Δ mice reached adolescence; however, they die at ~4 months of age due to heart failure. Ultrastructural analysis of SOD2Δ hearts revealed altered mitochondrial architecture, with prominent disruption of the cristae and vacuole formation. Noninvasive echocardiographic measurements in SOD2Δ mice showed dilated cardiomyopathic features such as decreased ejection fraction and fractional shortening along with increased left ventricular internal diameter. An increased incidence of ventricular tachycardia was observed during electrophysiological studies of the heart in SOD2Δ mice. Oxidative phosphorylation (OXPHOS) measurement using a Seahorse XF analyzer in SOD2Δ neonatal cardiomyocytes and adult cardiac mitochondria displayed reduced O2 consumption, particularly during basal conditions and after the addition of FCCP (H+ ionophore/uncoupler), compared to that in SOD2fl hearts. Measurement of extracellular acidification (ECAR) to examine glycolysis in these cells showed a pattern precisely opposite that of the oxygen consumption rate (OCR) among SOD2Δ mice compared to their SOD2fl littermates. Analysis of the activity of the electron transport chain complex identified a reduction in Complex I and Complex V activity in SOD2Δ compared to SOD2fl mice. We demonstrated that a deficiency of SOD2 increases reactive oxygen species (ROS), leading to subsequent overproduction of 4-HNE inside mitochondria. Mechanistically, proteins in the mitochondrial respiratory chain complex and TCA cycle (NDUFS2, SDHA, ATP5B, and DLD) were the target of 4-HNE adduction in SOD2Δ hearts. Our findings suggest that the SOD2 mediated 4-HNE signaling nexus may play an important role in cardiomyopathy
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