The Occurrence of PCBs and Chlorinated Pesticide Contaminants in Bottlenose Dolphins (Tursiops truncatus) in a Resident Community: Comparison with Age, Gender and Birth Order

Tissue samples from twenty bottlenose dolphins from a stable, residential community of coastal dolphins in the western Gulf of Mexico were analyzed for toxic PCB congeners and chlorinated pesticides. The tissues analyzed (blubber and melon) were from known individuals in a long-term (27+ y) study that stranded and were recovered for necropsy. Substantial demographic data were available on these individuals and utilized in the analysis of maternal transfer of organochlorines to young. The male dolphins in this study were shown to accumulate organochlorine contaminants with age. In female dolphins the organochlorine levels were found to decline with age. These results are in agreement with previous studies, with gestational and lactational transfer accounting for the decline seen in the females. A lengthening in interreproductive interval by increasing organochlorine levels after approximately age 30 y is noted in the females. For the first time, this study quantified the organochlorine levels of the first calf of a female, testing the hypothesis that the first-born of a female receives a substantially greater organochlorine load than subsequent calves. The first-born calf (age 5.3 mo) had the highest blubber ΣPCB, total DDT, HCB, and total pesticide levels of all animals in this study. The organochlorine levels in this calf were 2-5 fold higher than in a similarly aged, fourth-born calf. All animals in this study had appreciable EPCBlevels (range 0.07 - 26.9 ug/g wet weight; 2.6 - 203.2 ug/g lipid weight), and EDDT (range 0.06 - 10.3 wet weight; 0.9 - 88.1 ug/g lipid weight). These values are in a moderate range compared to other studies, but not far below levels at which western Gulf of Mexico bottlenose dolphins evidenced mortality events in 1990 and 1992. Further monitoring of this population is warranted

North Florida Trees

Artist Statement I began exploring manipulation and fabrication in the darkroom after a workshop in Alexander Diaz’s Introduction to Photography course. I have always had an affinity for nature, especially trees. I was especially moved by the barren trees seen during a cold North Florida winter. Growing up in Florida, I’m used to seeing the vast greenery brought by these trees, but there was just something about their emptiness during winter that really struck me. I wanted to capture and print them in a way that emphasized these qualities. Black and white film paired with splattering in the darkroom was a perfect medium for expressing these trees’ desolate and broken characteristics

Theorizing the Concept of Agency in Human-Algorithmic Ensembles with a Socio-Technical Lens

The growing relevance of algorithmic systems, including artificial intelligence, for processes of value creation raise theoretical and practical interest in the conceptualization of actorhood and the balancing of human and technological agencies within socio-technical ensembles. Prominent theories of the IS discipline still reflect a human-centric conceptualization of agency, which we deem challenged by advances in machine learning technology. We therefore motivate a revised theorizing of the concept of agency with a socio-technical lens. For that, we apply an inductive top-down theorizing approach. In this short paper, we present the first inductive step by describing tensions, oppositions and contradictions in the discourse on agency in IS literature of the last 30 years in the AIS Senior Scholars’ Basket of journals. The preliminary findings uncover a conceptual and ontological incoherence surrounding the concept of agency in IS scholarship, and a gap between reviewed publications and the agency claims of algorithmic systems

Short-term abstinence across potential behavioral addictions: a systematic review

Observing short-term abstinence effects across potential behavioral addictions is vital for informing understanding about how addiction-related symptoms (withdrawal, craving and relapse) might manifest across these behaviors. Short-term abstinence may also have potential as a clinical intervention for behavioral addictions. This review aimed to synthesize existing research evidence on short-term abstinence effects across potential behavioral addictions in light of (1) manifestations of withdrawal, craving and relapse, and (2) benefits or counterproductive consequences of abstinence. We reviewed 47 prospective studies examining effects of short-term abstinence across six potential behavioral addictions (exercise, gambling, gaming, mobile phone use, pornography use, social media use). Findings of the review showed that there is a paucity of prospective studies investigating abstinence effects in relation to potential behavioral addictions, except for exercise. Across all behaviors, exercise demonstrated the clearest pattern of withdrawal-related symptoms mainly related to mood disturbances. While withdrawal and craving were investigated to a fair extent across the studies, the study of relapse using abstinence protocols is underutilized within behavioral addiction research. Short-term abstinence shows promise as an intervention for some problematic behaviors, especially gaming, pornography use, mobile phone use, and social media use. However, potential counterproductive consequences of abstinence (e.g., rebound effects and compensatory behaviors) were not adequately assessed by the studies, which limits current evaluation of the utility of abstinence as an intervention

A New Cross-Shaped Graphite Furnace with Ballast Body for Reduction of Interferences in Atomic Absorption Spectrometry

A new crossed graphite furnace for atomic absorption spectrometry (GFAAS) was designed and installed in heated graphite atomizer (HGA500) combined with Perkin-Elmer spectrometer (AAS1100). The Tungsten ballast body was inserted inside one part of the crossed furnace in a way perpendicular to light path. The analyzed sample was injected manually on the ballast body inside the cross and pushed into the measuring zone using the original inner and additional purge gas. The sample was adsorbed strongly on the ballast and evaporated and transferred with different rates at different temperatures during the temperature program allowing the separation of analyte and matrix signals. Analysis of middle volatile element such as copper and manganese in standard urine sample (seronorm 2525) showed complete separation of analyte and background signals with good sensitivity and repeatability

The role of recreational online activities in school-based screen time sedentary behaviour interventions for adolescents: a systematic and critical literature review

Sedentary behaviours are highly associated with obesity and other important health outcomes in adolescence. This paper reviews screen time and its role within school-based behavioural interventions targeting adolescents between the years 2007 and 2019. A systematic literature review following PRISMA guidelines was conducted across five major databases to identify interventions targeting screen time—in addition to TV/DVD viewing. The review identified a total of 30 papers analysing 15 studies across 16 countries aiming at addressing reduction of recreational screen time (internet use and gaming) in addition to television/DVD viewing. All of the interventions focused exclusively on behaviour change, targeting in the majority both reduction of sedentary behaviours along with strategies to increase physical activity levels. A mix of intervention effects were found in the reviewed studies. Findings suggest aiming only for reduction in time spent on screen-based behaviour within interventions could be a limited strategy in ameliorating excessive screen use, if not targeted, in parallel, with strategies to address other developmental, contextual and motivational factors that are key components in driving the occurrence and maintenance of adolescent online behaviours. Additionally, it raises the need for a differential treatment and assessment of each online activity within the interventions due to the heterogeneity of the construct of screen time. Recommendations for enhancing the effectiveness of school-based sedentary behaviour interventions and implications for public policy are discussed

Mind over matter: testing the efficacy of an online randomized controlled trial to reduce distraction from smartphone use

Evidence suggests a growing call for the prevention of excessive smartphone and social media use and the ensuing distraction that arises affecting academic achievement and productivity. A ten-day online randomized controlled trial with the use of smartphone apps, engaging participants in mindfulness exercises, self-monitoring and mood tracking, was implemented amongst UK university students (n = 143). Participants were asked to complete online pre-and post-intervention assessments. Results indicated high effect sizes in reduction of smartphone distraction and improvement scores on a number of self-reported secondary psychological outcomes. The intervention was not effective in reducing habitual behaviours, nomophobia, or time spent on social media. Mediation analyses demonstrated that: (i) emotional self-awareness but not mindful attention mediated the relationship between intervention effects and smartphone distraction, and (ii) online vigilance mediated the relationship between smartphone distraction and problematic social media use. The present study provides preliminary evidence of the efficacy of an intervention for decreased smartphone distraction and highlights psychological processes involved in this emergent phenomenon in the smartphone literature. Online interventions may serve as complementary strategies to reduce distraction levels and promote insight into online engagement. More research is required to elucidate the mechanisms of digital distraction and assess its implications in problematic use

Approximate Inference for Robust Gaussian Process Regression

Gaussian process (GP) priors have been successfully used in non-parametric Bayesian regression and classification models. Inference can be performed analytically only for the regression model with Gaussian noise. For all other likelihood models inference is intractable and various approximation techniques have been proposed. In recent years expectation-propagation (EP) has been developed as a general method for approximate inference. This article provides a general summary of how expectation-propagation can be used for approximate inference in Gaussian process models. Furthermore we present a case study describing its implementation for a new robust variant of Gaussian process regression. To gain further insights into the quality of the EP approximation we present experiments in which we compare to results obtained by Markov chain Monte Carlo (MCMC) sampling