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Previous history of activity and learning modulates synaptic plasticity and can lead to saturation of synaptic connections. According to the synaptic homeostasis hypothesis, neural oscillations during slow-wave sleep play an important role in restoring plasticity within a functional range. However, it is not known whether slow-wave oscillations—without the concomitant requirement of sleep—play a causal role in human synaptic homeostasis. Here, we aimed to answer this question using transcranial alternating current stimulation (tACS) to induce slow-oscillatory activity in awake human participants. tACS was interleaved between two plasticity-inducing interventions: motor learning, and paired associative stimulation (PAS). The hypothesis tested was that slow-oscillatory tACS would prevent homeostatic interference between motor learning and PAS, and facilitate plasticity from these successive interventions. Thirty-six participants received sham and active fronto-motor tACS in two separate sessions, along with electroencephalography (EEG) recordings, while a further 38 participants received tACS through a control montage. Motor evoked potentials (MEPs) were recorded throughout the session to quantify plasticity changes after the different interventions, and the data were analysed with Bayesian statistics. As expected, there was converging evidence that motor training led to excitatory plasticity. Importantly, we found moderate evidence against an effect of active tACS in restoring PAS plasticity, and no evidence of lasting entrainment of slow oscillations in the EEG. This suggests that, under the conditions tested here, slow-oscillatory tACS does not modulate synaptic homeostasis in the motor system of awake humans.

Aims Despite lithium's clinical efficacy, it is commonly thought that its use is declining. The objective of this study is to describe the new and prevalent lithium users as well as rates of discontinuation of lithium use over a 10-year period. Methods This study used provincial administrative health data from Alberta, Canada between January 1, 2009 and December 31, 2018. Lithium prescriptions were identified within the Pharmaceutical Information Network database. Total and subgroup specific frequencies of new and prevalent lithium use were determined over the 10-year study period. Lithium discontinuation was also estimated through survival analysis. Results Between the calendar years of 2009 and 2018, 580,873 lithium prescriptions were dispensed in Alberta to 14,008 patients. The total number of new and prevalent lithium users appears to be decreasing over the 10-year timeframe, although the decline may have stopped or reversed in the latter years of the study period. Prevalent use of lithium was lowest among individuals between the ages of 18–24 years while the highest number of prevalent users were in the 50–64 age group, particularly among females. New lithium use was lowest amongst those 65 years and older. More than 60% (8,636) of patients prescribed lithium, discontinued use during the study timeframe. Lithium users between ages of 18–24 years were at the highest risk of discontinuations. Conclusions Rather than a general decline in prescribing, trends in lithium use are dependent on age and sex. Further, the period soon after lithium initiation appears to be a key time period in which many lithium trials are abandoned. Detailed studies using primary data collection are needed to confirm and further explore these findings. These population-based results not only confirm a decline in lithium use, but also suggest that this may have stopped or even reversed. Population-based data on discontinuation pinpoint the period soon after initiation as the time when trials are most often discontinued.

Previous history of activity and learning modulates synaptic plasticity and can lead to saturation of synaptic connections. According to the synaptic homeostasis hypothesis, neural oscillations during slow-wave sleep play an important role in restoring plasticity within a functional range. However, it is not known whether slow-wave oscillations – without the concomitant requirement of sleep – play a causal role in human synaptic homeostasis. Here, slow-oscillatory transcranial alternating current stimulation (tACS, 1Hz, 1mA, 18 minutes) was interleaved between two plasticity-inducing interventions: motor learning, and a paradigm known to induce long-term-potentiation-like plasticity in human motor cortex (paired associative stimulation; PAS). The hypothesis tested was that slow-oscillatory tACS would abolish the expected interference between motor learning and PAS, and facilitate plasticity from successive interventions. Thirty-six participants received sham and active fronto-motor tACS in two separate sessions, along with electroencephalography (EEG) recordings. A further 38 participants received tACS through a control (posterior midline) montage. Using neuro-navigated transcranial magnetic stimulation (TMS) over the left motor cortex, motor evoked potentials (MEPs) were recorded throughout the session. Bayesian statistics were used to quantify evidence for or against the hypothesis of an effect of each intervention on MEP amplitude. As expected, there was converging evidence that motor training increased MEPs. Importantly, we found moderate evidence against an effect of active tACS in restoring PAS plasticity, and no evidence of lasting entrainment of slow-oscillations in the EEG. This suggests that, under the conditions tested here, slow-oscillatory tACS does not modulate synaptic homeostasis in the motor system of awake humans.

Biodiversity is believed to be closely related to ecosystem functions. However, the ability of existing biodiversity measures, such as species richness and phylogenetic diversity, to predict ecosystem functions remains elusive. Here, we propose a new vector of diversity metrics, structural diversity, which directly incorporates niche space in measuring ecosystem structure. We hypothesize that structural diversity will provide better predictive ability of key ecosystem functions than traditional biodiversity measures. Using the new lidar-derived canopy structural diversity metrics on 19 National Ecological Observation Network forested sites across the USA, we show that structural diversity is a better predictor of key ecosystem functions, such as productivity, energy, and nutrient dynamics than existing biodiversity measures (i.e. species richness and phylogenetic diversity). Similar to existing biodiversity measures, we found that the relationships between structural diversity and ecosystem functions are sensitive to environmental context. Our study indicates that structural diversity may be as good or a better predictor of ecosystem functions than species richness and phylogenetic diversity.

Human trafficking is a global phenomenon. The UK is predominantly, although not exclusively, a destination country for trafficked persons (Europol, 2006). It has become apparent through academic research and debate that there is a lack of empirical research and data available which addresses the reality of access by trafficked persons to certainmeans of communication (internet, mobile phone technology or more traditional means, aPC); therefore meaning that any attempts to use these mediums to assist or identify trafficked individuals are based on speculation rather than empiricism. The aims and objectives of this research are to conduct semi-structured interviews with professionals who work with trafficked people, or in related fields (e.g., Immigration agencies, police, victim support, therapists) (n = 13) with a view to establishing more clearly the level of access trafficked persons/putatively trafficked persons have to communication technology. The participants have been identified through purposive and snowballing sampling techniques(Robson, 2011), and are the best group to utilise as their understandings, as well as attitudes, inform policy and practice in this area. This research looks to identify a general understanding of trafficked people’s access to communication technology; how access to this technology either helps or hinders them escape their current situation; and, consequentially, how understanding the effect of communication technology assists us in how we understand as well as respond to trafficking nationally and internationally.

This commentary analyses the Court of Appeal decision in R v. O, and considers the implications of misidentification of victims of human trafficking, both in the light of the UK's obligations with respect to these victims at the time of the decision in O, and following signature and ratification of the Council of Europe Convention on Action against Trafficking in Human Beings. A custodial sentence had been imposed upon O as a result of her attempt to leave the UK using false identification documents. Had she been identified as a victim of human trafficking - and there were ample opportunities for this to happen - she may not have had to endure the trauma which resulted from her conviction. Due to the fact that the Trafficking Convention was not in force in the UK at the time of the decision, it was necessary for Laws - to draw upon sources that were available at the time; notably, the European Convention on Human Rights. Although implementation of the Trafficking Convention has brought about more favourable conditions for this vulnerable body of persons, enjoyment of the ‘rights’ contained within it is wholly dependent upon correct and timely identification of an individual as a victim of human trafficking. This case highlights both the need for training for those who may come into contact with victims of trafficking, such as immigration authorities and legal representatives, and the importance of procedures that aid rapid identification so that victims of human trafficking have access to their rights.

Following the drafting of the Council of Europe Convention on Action against Trafficking in Human Beings, 2005, it would seem that a more victim-focused, victim-centric approach is being taken toward the individuals who fall foul of this transnational phenomenon than previously has been the case. The more encompassing provisions of this Convention, when compared to the somewhat weak provisions enshrined in the United Nations Protocol to Prevent, Suppress and Punish Trafficking in Persons, 2000, provide for various bespoke rights such as rest and recovery periods and temporary residence permits for those subject to its provisions.

The 13th North American Caribou Workshop which was held in Winnipeg, Manitoba, was a great success with more than 400 participants: people from Canada, the United States, Norway and Greenland, representatives from co-management and resource management boards across North America, First Nations, Inuit and Inuvialuit, governmental and non-governmental organisations, private companies, researchers, students and youth. The theme of the Workshop was Sustaining Caribou and their Landscapes – Knowledge to Action and the intent of the organizers was twofold: first, to provide participants with the opportunity to share scientific and traditional knowledge on different subspecies and ecotypes of Rangifer across the circumpolar North, the particularities of the different landscapes and land use management issues; second, to explore innovative ways to transfer knowledge to action, ensuring the long-term persistence of Rangifer throughout its range through the development of better governance structures, sound policies and effective communication.