A STUDY OF EXTRACELLULAR SPACE IN CENTRAL NERVOUS TISSUE BY FREEZE-SUBSTITUTION

It was attempted to preserve the water distribution in central nervous tissue by rapid freezing followed by substitution fixation at low temperature. The vermis of the cerebellum of white mice was frozen by bringing it into contact with a polished silver mirror maintained at a temperature of about -207°C. The tissue was subjected to substitution fixation in acetone containing 2 per cent OsO4 at -85°C for 2 days, and then prepared for electron microscopy by embedding in Maraglas, sectioning, and staining with lead citrate or uranyl acetate and lead. Cerebellum frozen within 30 seconds of circulatory arrest was compared with cerebellum frozen after 8 minutes' asphyxiation. From impedance measurements under these conditions, it could be expected that in the former tissue the electrolyte and water distribution is similar to that in the normal, oxygenated cerebellum, whereas in the asphyxiated tissue a transport of water and electrolytes into the intracellular compartment has taken place. Electron micrographs of tissue frozen shortly after circulatory arrest revealed the presence of an appreciable extracellular space between the axons of granular layer cells. Between glia, dendrites, and presynaptic endings the usual narrow clefts and even tight junctions were found. Also the synaptic cleft was of the usual width (250 to 300 A). In asphyxiated tissue, the extracellular space between the axons is either completely obliterated (tight junctions) or reduced to narrow clefts between apposing cell surfaces

PenQuest Volume 5, Number 1

Table of Contents for this Volume: Success by Shatney Maria by Jane O’Neal Intrusions by Mark McBride The Mystery of the Back Porch Light by Nature Johnston Truth and the Violin by Shatney Corporate America by Julie Crowell Pete’s Cafe by Nature Johnston Geranium by Anne Benjamin The Man Who Buried His Books by William Slaughter Erasures by William Slaughter Mind You and other poems by Kate Mathews Coffee in the Tea Room by Kathleen O’Brien The Children by Katharine Rodier Sisters, Reclamation, Not Wanting to Say, “I Told You So,” But… by Kathleen O’Brien Genetics by Kathleen O’Brien The Anguish of Flames by Kathleen O’Brien turning plows by Mark McBride A Valediction for My Father by Jonathan Williams Untitled by Mark Sablow Artificial Portrait by Kevin Christenson Untitled by Latrell Mickler Untitled by Kevin Christenson Galvanistic Ascension by Mark Grisham Power Surge by Mark Grisham Untitled by Lori Kirsbau

Childhood in Sociology and Society: The US Perspective

The field of childhood studies in the US is comprised of cross-disciplinary researchers who theorize and conduct research on both children and youth. US sociologists who study childhood largely draw on the childhood literature published in English. This article focuses on American sociological contributions, but notes relevant contributions from non-American scholars published in English that have shaped and fueled American research. This article also profiles the institutional support of childhood research in the US, specifically outlining the activities of the ‘Children and Youth’ Section of the American Sociological Association (ASA), and assesses the contributions of this area of study for sociology as well as the implications for an interdisciplinary field.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Ineffectiveness of light emitting diodes as underwater deterrents for Long-tailed Ducks Clangula hyemalis

Gillnet bycatch accounts for over 400,000 bird mortalities worldwide every year, affectinga wide variety of species, especially those birds that dive when foraging. Technologicalsolutions to improve gillnet visibility or deter birds from approaching nets, such as LEDlights, are essential for aiding diving birds to perceive nets as a hazard. Designing suchsolutions requires obtaining visual and behavioural ecology information from species toassess their ability to see the warning devices, and to examine their behavioural responsesto them. Seaducks, particularly Long-tailed DucksClangula hyemalis,have high bycatchmortality rates. We examined the visualfields of four Long-tailed Ducks to understandtheir three-dimensional view around the head. The visualfield characteristics of thisspecies indicate a reliance on visual guidance for foraging associated with their capture ofvaried, mobile prey in their generalist diet. We subsequently conducted dive tank trials totest the effectiveness of 12 different LED treatments as visual deterrents to the underwaterforaging behaviour of 8 Long-tailed Ducks. During each trial, ducks were offered foodrewards from a specific underwater location in a dive tank, having the choice of whether totake the food or not. At the same time, they were exposed to either one LED light or thecontrol (no light) to determine whether the presence of each light affected the foragingsuccess rate of dives compared to the control. Exposure of ducks to all 13 treatmentcombinations was randomised over the trial period. White lights with an increasingflashrate were shown to have a significant positive effect on foraging success, and likely acted asa visual attractant, rather than as a deterrent. No light treatment significantly reduced theforaging success of ducks. LED lights did not inhibit the feeding of Long-tailed Ducks. Suchlights may be ineffective as underwater visual deterrents when deployed on gillnets, whilewhiteflashing lights may make foraging sites more attractive to Long-tailed Ducks.©2020 The Authors. Published by Elsevier B.V. This is an open access article under the CCBY-NC-ND license

Emotional Dysregulation as a target in the treatment of co-existing substance use and borderline personality disorders: A pilot study

Background: Borderline Personality Disorder (BPD) and Substance Use Disorders (SUD) are frequently co-morbid and their co-occurrence exacerbates the symptomatology and associated harms for both disorders. However, few intervention studies have examined the delivery of an integrated intervention for BPD and SUD within alcohol and other drug (AOD) treatment settings. This single arm pilot study examined the clinical utility and outcomes of a 12-session emotion regulation intervention for clients with co-occurring SUD and BPD symptoms delivered in an outpatient AOD treatment setting. Method: Forty-five adult treatment-seekers (64.4% women, mean age 35.8 years [SD=10.4]) attending an outpatient AOD service, who exhibited three or more symptoms of BPD, engaged in a 12-session emotion regulation intervention. Clinical measures assessing alcohol and drug use, BPD symptoms, emotion dysregulation and acceptance, non-avoidance of thoughts and emotions, and psychological flexibility were collected at baseline, session six and session 12. Treatment engagement, satisfaction and rapport were also measured. Results: Fifty-one percent of participants completed the 12-session intervention. The results demonstrated that the number of drug using occasions in the past 28 days significantly reduced from baseline compared to session 12. Furthermore, a significant reduction was identified in BPD symptom severity, emotion dysregulation, and non-acceptance, experiential avoidance and psychological inflexibility from baseline to session 12. Conclusions: For those individuals who completed the 12-session emotion regulation intervention, there were significant reductions across a number of clinical outcomes. However, retention in treatment for this vulnerable client group remains a significant challenge in the AOD setting