Anecdotal reports from blue crab fishermen in the Indian River Lagoon (IRL), Florida suggested that bottlenose dolphins (Tursiops truncatus) followed their boats, and stole bait fish from crab pots ...soon after they were deployed. To investigate these reports, we made biweekly observations from IRL commercial crab boats from January 1998 to January 1999 (670 h). Only 2.8% of the 18,891 crab pots surveyed revealed evidence of dolphin/crab pot interaction. Dolphin interactions included: (1) begging at boats, (2) feeding on discarded bait fish, (3) engaging in crab pot tipping behavior, and (4) dolphin mortality from crab pot float line entanglement. Overall, 16.6% of the 1,296 dolphins sighted interacted with fishing boats. Seasonal trends were evident, with fishery interactions peaking in the summer. Crab pot interactions ranged from 0% to 36% of the traps checked daily. Different methods of securing the bait‐well door and the role of trap locality were tested using a replicated experimental design. Results showed significant differences in successful bait removal by dolphins, among the degrees of door security (P < 0.001) and between trap location (P < 0.01). Thus, increased door security may help to reduce the negative impacts to the fishery and dolphins involved.
Navorsingsgegewens oor prestasie in 'n tweede taal kan nie sonder meer op Afrikaans by swart leerders van toepassing gemaak word nie, gesien in die lig daarvan dat swart leerders nie in hulle ...moedertaal onderrig word nie, maar in Engels wat alreeds hulle tweede taal is. 'n Verdere probleem is dat vorige ondersoeke nie beide kognitiewe en affektiewe veranderlikes betrek het nie. Die kwaliteit van onderrig of leerstyl van die leerders word ook nie gelyktydig saam met kognitiewe en affektiewe veranderlikes ondersoek nie. Dit is gevolglik moeilik om vas te stel watter van hierdie veranderlikes as die belangrikste beskou kan word ten einde die variansie in die prestasie van Afrikaans as 'n tweede taal te kan verklaar. 'n Empiriese ondersoek is uitgevoer waarby 174 swart hoërskoolleerders betrek is. Kognitiewe en affektiewe veranderlikes, asook leerders se leerstyle, is gemeet. Uit die empiriese ondersoek blyk dit dat selfkonsep, geheue, verbale begrip en motivering as die belangrikste veranderlikes beskou kan word wat met prestasie in Afrikaans as tweede taal verband hou. Leerstyl is nie as 'n belangrike faktor geïdentifiseer nie. Uit die resultate kan twee spesifieke aanbevelings gemaak word: Eerstens moet die belangrikheid van lees opnuut deur onderwysers beklemtoon word. Die aanbeveling word gemaak op grond daarvan dat verbale begrip as 'n belangrike kognitiewe veranderlike na vore gekom het. Verbale begrip hou verband met aspekte soos woordeskat-uitbreiding en sinskonstruksie wat in 'n groot mate deur leesaktiwiteite bevorder word (Echols, West, Stanovich & Zehr 1996:296-304). Tweedens moet onderwysers daarop bedag wees dat affektiewe faktore 'n belangrike rol in die klaskamer speel waar 'n tweede taal onderrig word.
Based on existing pharmacokinetic models for benzene, the distribution and retention of activity after inhalation of 14C-labelled benzene in humans were studied. Six different benzene concentrations ...from 0.1 to 10,000 ppm (corresponding to activity concentrations between 9.6 x 106 and 9.6 x 1011 Bq m-3) and five exposure times from 0.1 to 1000 min were considered. The cumulated activities in the different organs and tissues and the urinary excretion rates were observed to depend non-linearly on the activity intake. The fraction of activity removed via urine varies between 52 and 10% of the intake. Nevertheless, for times that are long compared to the exposure duration the urinary excretion rate is determined by the activity clearance from adipose tissue and thus decreases at a constant rate. This decrease is common for all exposure conditions examined and thus allowed determining a mean urinary excretion rate and corresponding dose coefficients for committed equivalent doses as well as for the effective dose. The uncertainty of the dose coefficients is estimated to be about 50% for the exposure range covered. A 14-day interval for the incorporation monitoring by urine activity counting seems to be reasonable.
The International Commission on Radiological Protection has recently issued Publication 88, giving dose coefficients for the embryo, fetus and newborn child from intakes of selected radionuclides of ...31 elements by the mother, either before or during pregnancy. The biokinetic models used for calculating these doses were based upon the available human data and the results of animal experiments. This paper summarises the approach used for the development of biokinetic and dosimetric models. It also compares the estimates of dose received by the offspring with those received by the reference adult. The main findings are that, in general, doses to the offspring are similar to or lower than those to the reference adult. For a few radionuclides, however, the dose to the offspring can exceed that to the adult. The reasons for these variations in comparative dose are examined.
Evidence-based psychosocial treatments for schizophrenia founded on Western belief systems and values may not be efficacious in different cultures without adaptation. This systematic review analyses ...the nature and outcomes of culturally-adapted psychosocial interventions in schizophrenia, examining how interventions have been adapted, their efficacy and what features drive heterogeneity in outcome.
Articles identified by searching electronic databases from inception to 3 March 2016, reference lists and previous reviews were independently screened by two authors for eligible controlled trials. Data on the nature of adaptations was analysed inductively using thematic analyses. Meta-analyses were conducted using random effects models to calculate effect sizes (Hedges' g) for symptoms.
Forty-six studies with 7828 participants were included, seven adapted for minority populations. Cultural adaptations were grouped into nine themes: language, concepts and illness models, family, communication, content, cultural norms and practices, context and delivery, therapeutic alliance, and treatment goals. Meta-analyses showed significant post-treatment effects in favour of adapted interventions for total symptom severity (n = 2345, g: -0.23, 95% confidence interval (CI) -0.36 to -0.09), positive (n = 1152, g: -0.56, 95% CI -0.86 to -0.26), negative (n = 855, g: -0.39, 95% CI -0.63 to -0.15), and general (n = 525, g: -0.75, CI -1.21 to -0.29) symptoms.
The adaptation process can be described within a framework that serves as a benchmark for development or assessment of future adaptations. Culturally adapted interventions were more efficacious than usual treatment in proportion to the degree of adaptation. There is insufficient evidence to show that adapted interventions are better than non-adapted interventions. Features of context, intervention and design influenced efficacy. Investigating whether adaptation improves efficacy, most importantly amongst ethnic minorities, requires better designed trials with comparisons against unadapted interventions.
Common bottlenose dolphins (Tursiops truncatus truncatus) inhabiting the Indian River Lagoon (IRL) estuarine system along the east coast of Florida are impacted by anthropogenic activities and have ...had multiple unexplained mortality events. Given this, managers need precise estimates of demographic and abundance parameters. Mark-recapture photo-identification boat-based surveys following a Robust Design were used to estimate abundance, adult survival, and temporary emigration for the IRL estuarine system stock of bottlenose dolphins. Models allowed for temporary emigration and included a parameter (time since first capture) to assess evidence for transient individuals. Surveys (n = 135) were conducted along predetermined contour and transect lines throughout the entire IRL (2016-2017). The best fitting model allowed survival to differ for residents and transients and to vary by primary period, detection to vary by secondary session, and did not include temporary emigration. Dolphin abundance was estimated from 981 (95% CI: 882-1,090) in winter to 1,078 (95% CI: 968-1,201) in summer with a mean of 1,032 (95% CI: 969-1,098). Model averaged seasonal survival rate for marked residents was 0.85-1.00. Capture probability was 0.20 to 0.42 during secondary sessions and the transient rate was estimated as 0.06 to 0.07. This study is the first Robust Design mark-recapture survey to estimate abundance for IRL dolphins and provides population estimates to improve future survey design, as well as an example of data simulation to validate and optimize sampling design. Transients likely included individuals with home ranges extending north of the IRL requiring further assessment of stock delineation. Results were similar to prior abundance estimates from line-transect aerial surveys suggesting population stability over the last decade. These results will enable managers to evaluate the impact of fisheries-related takes and provide baseline demographic parameters for the IRL dolphin population which contends with anthropogenic impacts and repeated mortality events.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Vacuum windows are required in magnetically confined fusion experiments to provide possibilities to observe the plasma in a wide range of electromagnetic wavelengths. The window disk consists of a ...dielectric, e.g. Fused Silica (SiO2), Sapphire or Chemically Vapourised Diamond (CVD). As electromagnetic waves pass through the disk, a fraction of the beam power is dissipated resulting in a temperature increase of the disk. In Electron Cyclotron Waves (ECW) heated plasmas the dissipation in the window disk can be very high. The computation of dielectric losses for a collimated beam with known incidence angle, polarisation and loss tangent (measure for the intrinsic dielectric loss) is well established. However, the dielectric losses in diagnostic windows mostly result from microwave stray radiation, which results from a modest, but inevitable, fraction of non-absorbed ECW. This fraction diffuses in the vessel by many reflections into rays with random k-vector and with random polarisation. In this work the thermal load on the window disk by microwave stray radiation is assessed. The load by a collimated beam is studied as a function of incidence angle and polarisation allowing to average over a distribution of incident rays. An experiment was commissioned measuring the loss tangent of a number of commercially available SiO2 disks at low power in an open resonator, and subsequently measuring the dielectric heating of these disks at high power stray radiation using the facility ’MISTRAL’ at Wendelstein-7X. The experimental results are compared to modelling and it is demonstrated that, in the parameter range considered, single-pass fractional absorption may be applied while taking a safety margin that arises from the minima and maxima due to multiple reflections.
•Measurement and modelling of stray radiation dielectric losses in vacuum windows.•Measurement data on loss tangent and permittivity at millimetre range frequencies.•Stray radiation exposure of a dielectric slab.
Common bottlenose dolphins (Tursiops truncatus truncatus) inhabiting the Indian River Lagoon (IRL) estuarine system along the east coast of Florida are impacted by anthropogenic activities and have ...had multiple unexplained mortality events. Given this, managers need precise estimates of demographic and abundance parameters. Mark-recapture photo-identification boat-based surveys following a Robust Design were used to estimate abundance, adult survival, and temporary emigration for the IRL estuarine system stock of bottlenose dolphins. Models allowed for temporary emigration and included a parameter (time since first capture) to assess evidence for transient individuals. Surveys (n = 135) were conducted along predetermined contour and transect lines throughout the entire IRL (2016-2017). The best fitting model allowed survival to differ for residents and transients and to vary by primary period, detection to vary by secondary session, and did not include temporary emigration. Dolphin abundance was estimated from 981 (95% CI: 882-1,090) in winter to 1,078 (95% CI: 968-1,201) in summer with a mean of 1,032 (95% CI: 969-1,098). Model averaged seasonal survival rate for marked residents was 0.85-1.00. Capture probability was 0.20 to 0.42 during secondary sessions and the transient rate was estimated as 0.06 to 0.07. This study is the first Robust Design mark-recapture survey to estimate abundance for IRL dolphins and provides population estimates to improve future survey design, as well as an example of data simulation to validate and optimize sampling design. Transients likely included individuals with home ranges extending north of the IRL requiring further assessment of stock delineation. Results were similar to prior abundance estimates from line-transect aerial surveys suggesting population stability over the last decade. These results will enable managers to evaluate the impact of fisheries-related takes and provide baseline demographic parameters for the IRL dolphin population which contends with anthropogenic impacts and repeated mortality events.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The significance of metal concentrations in marine mammals is not well understood and relating concentrations between stranded and free-ranging populations has been difficult. In order to predict ...liver concentrations in free-ranging dolphins, we examined concentrations of trace elements (Al, As, Ba, Be, Cd, Co, Cu, Fe, Li, Mn, Ni, Pb, Sb, Se, Sn, total Hg (THg), V, Zn) in skin and liver of stranded bottlenose dolphins (Tursiops truncatus) from the South Carolina (SC) coast and the Indian River Lagoon, Florida (FL) during 2000–2008. Significantly higher concentrations of Zn, Fe, Se, Al, Cu and THg were found in skin while liver exhibited significantly higher Cu, Fe, Mn and THg concentrations for both study sites. Mean skin concentrations of Cu and Mn were significantly higher in SC dolphins while higher concentrations of THg and V were found in FL dolphins. In addition, liver tissues in SC dolphins exhibited significantly higher As concentrations while higher Fe, Pb, Se, THg, and V levels were found in FL dolphins. Two elements (Cu and THg) showed significant age-related correlations with skin concentration while five elements (Cu, Se, THg, Zn and V) showed age-related correlations with liver concentrations. Geographic location influenced age-related accumulation of several trace elements and age-related accumulation of THg in hepatic tissue was observed for both sites to have the highest correlations (r2=0.90SC; r2=0.69FL). Mean THg concentration in liver was about 10 times higher in FL dolphins (330μgg−1dw) than those samples from SC dolphins (34.3μgg−1dw). The mean molar ratio of Hg to Se was 0.93±0.32 and 1.08±0.38 for SC and FL dolphins, respectively. However, the Hg:Se ratio varied with age as much lower ratios (0.2–0.4) were found in younger animals. Of the 18 measured elements, only THg was significantly correlated in skin and liver of stranded dolphins and skin of free-ranging dolphins from both sites suggesting that skin may be useful in predicting Hg concentrations in liver tissue of free-ranging dolphins. Results indicate that 33% of the stranded and 15% of the free-ranging dolphins from FL exceed the minimum 100μgg−1 wet weight (ww) (∼400dw) Hg threshold for hepatic damage while none from SC reached this level. Hepatic concentrations of As in SC dolphins and V in FL dolphins were also highly correlated with skin concentrations which may have some regional specificity predictive value. The present study provides the first application of trace element concentrations derived from stranded bottlenose dolphins to predict liver concentrations in free-ranging populations.
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