135 research outputs found
High-Resolution Dynamics of Hydrogen Peroxide on the Surface of Scleractinian Corals in Relation to Photosynthesis and Feeding
We developed and used a microsensor to measure fast (<1 s) dynamics of hydrogen peroxide (H2O2) on the polyp tissue of two scleractinian coral species (Stylophora pistillata and Pocillopora damicornis) under manipulations of illumination, photosynthesis, and feeding activity. Our real-time tracking of H2O2 concentrations on the coral tissue revealed rapid changes with peaks of up to 60 mu M. We observed bursts of H2O2 release, lasting seconds to minutes, with rapid increase and decrease of surficial H2O2 levels at rates up to 15 mu M s(-1). We found that the H2O2 levels on the polyp surface are enhanced by oxygenic photosynthesis and feeding, whereas H2O2 bursts occurred randomly, independently from photosynthesis. Feeding resulted in a threefold increase of baseline H2O2 levels and was accompanied by H2O2 bursts, suggesting that the coral host is the source of the bursts. Our study reveals that H2O2 levels at the surface of coral polyps are much higher and more dynamic than previously reported, and that bursts are a regular feature of the H2O2 dynamics in the coral holobiont
S. Hendrickx: Love, Sex & Long-Term Relationships: What People with Asperger Syndrome Really Really Want: Jessica Kingsley Publishers, London, UK, 2008, 144 pp, ISBN 978-1-84310-605-0. $19.95 (paper)
Call to Action: The Impact of Cyberbullying in the COVID Era
Given the recent COVID-19 pandemic, research suggests that students are spending an increased amount of time online. Consequently, the opportunity for students engaged in, or students who are a victim of cyberbullying has increased as well. Bullying no longer begins and ends with the school bells, it has infiltrated every aspect of studentsâ lives through the internet. Similarly, to bullying, cyberbullying leads to negative outcomes; the purpose of this article is to identify support, prevention, and intervention suggestions for parents, educators and schools, and mental health providers to decrease studentsâ cyberbullying involvement
Prenatal hypoxia induces increased cardiac contractility on a background of decreased capillary density.
Background: Chronic hypoxia in utero (CHU) is one of the most common insults to fetal development and may be associated with poor cardiac recovery from ischaemia-reperfusion injury,yet the effects on normal cardiac mechanical performance are poorly understood.
Methods: Pregnant female wistar rats were exposed to hypoxia (12% oxygen, balance nitrogen)for days 10â20 of pregnancy. Pups were born into normal room air and weaned normally. At 10 weeks of age, hearts were excised under anaesthesia and underwent retrograde 'Langendorff' perfusion. Mechanical performance was measured at constant filling pressure (100 cm H2O) with intraventricular balloon. Left ventricular free wall was dissected away and capillary density estimated following alkaline phosphatase staining. Expression of SERCA2a and Nitric Oxide Synthases (NOS) proteins were estimated by immunoblotting.
Results: CHU significantly increased body mass (P < 0.001) compared with age-matched control rats but was without effect on relative cardiac mass. For incremental increases in left ventricular balloon volume, diastolic pressure was preserved. However, systolic pressure was significantly greater following CHU for balloon volume = 50 ÎŒl (P < 0.01) and up to 200 ÎŒl (P < 0.05). For higher balloon volumes systolic pressure was not significantly different from control. Developed pressures were correspondingly increased relative to controls for balloon volumes up to 250 ÎŒl (P < 0.05).Left ventricular free wall capillary density was significantly decreased in both epicardium (18%; P <0.05) and endocardium (11%; P < 0.05) despite preserved coronary flow. Western blot analysis revealed no change to the expression of SERCA2a or nNOS but immuno-detectable eNOS protein was significantly decreased (P < 0.001) in cardiac tissue following chronic hypoxia in utero.
Conclusion: These data offer potential mechanisms for poor recovery following ischaemia, including decreased coronary flow reserve and impaired angiogenesis with subsequent detrimental effects of post-natal cardiac performance
Subthreshold psychosis in 22q11.2 deletion syndrome: multisite naturalistic study
Nearly one-third of individuals with 22q11.2 deletion syndrome (22q11.2DS) develop a psychotic disorder during life, most of them by early adulthood. Importantly, a full-blown psychotic episode is usually preceded by subthreshold symptoms. In the current study, 760 participants (aged 6-55 years) with a confirmed hemizygous 22q11.2 microdeletion have been recruited through 10 medical sites worldwide, as part of an international research consortium. Of them, 692 were nonpsychotic and with complete measurement data. Subthreshold psychotic symptoms were assessed using the Structured Interview for Prodromal Syndromes (SIPS). Nearly one-third of participants met criteria for positive subthreshold psychotic symptoms (32.8%), less than 1% qualified for acute positive subthreshold symptoms, and almost a quarter met criteria for negative/disorganized subthreshold symptoms (21.7%). Adolescents and young adults (13-25 years) showed the highest rates of subthreshold psychotic symptoms. Additionally, higher rates of anxiety disorders and attention deficit/hyperactivity disorder (ADHD) were found among the study participants with subthreshold psychotic symptoms compared to those without. Full-scale IQ, verbal IQ, and global functioning (GAF) scores were negatively associated with participants' subthreshold psychotic symptoms. This study represents the most comprehensive analysis reported to date on subthreshold psychosis in 22q11.2DS. Novel findings include age-related changes in subthreshold psychotic symptoms and evidence that cognitive deficits are associated with subthreshold psychosis in this population. Future studies should longitudinally follow these symptoms to detect whether and how early identification and treatment of these manifestations can improve long-term outcomes in those that eventually develop a psychotic disorder
Gender comparisons of fat talk in the United Kingdom and the United States
This study compared different forms of body talk, including "fat talk," among 231 university men and women in central England (UK; n = 93) and the southeastern United States (US; n = 138). A 2 (gender) by 2 (country) repeated measures ANOVA across types of body talk (negative, self-accepting, positive) and additional Chi-square analyses revealed that there were differences across gender and between the UK and US cultures. Specifically, UK and US women were more likely to report frequently hearing or perceiving pressure to engage in fat talk than men. US women and men were also more likely to report pressure to join in self-accepting body talk than UK women and men
Effectiveness of teaching strategies on the development of critical thinking in undergraduate nursing students: a meta-analysis
A cognitive decline precedes the onset of psychosis in patients with the 22q11.2 deletion syndrome
Patients with 22q11.2 deletion syndrome (22q11DS) have an elevated (25%) risk for developing schizophrenia. Recent reports have suggested that a subgroup of children with 22q11DS display a substantial decline in cognitive abilities, starting at a young age
Trichoderma spp. NA EMERGĂNCIA E CRESCIMENTO DE MUDAS DE CAMBARĂ (Gochnatia polymorpha (Less.) Cabrera)1
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