Towards a computational model for stimulation of the Pedunculopontine nucleus

The pedunculopontine nucleus (PPN) has recently been suggested as a new therapeutic target for deep brain stimulation (DBS) in patients suffering from Parkinson's disease, particularly those with severe gait and postural impairment [1]. Stimulation at this site is typically delivered at low frequencies in contrast to the high frequency stimulation required for therapeutic benefit in the subthalamic nucleus (STN) [1]. Despite real therapeutic successes, the fundamental physiological mechanisms underlying the effect of DBS are still not understood. A hypothesis is that DBS masks the pathological synchronized firing patterns of the basal ganglia that characterize the Parkinsonian state with a regularized firing pattern. It remains unclear why stimulation of PPN should be applied with low frequency in contrast to the high frequency stimulation of STN. To get a better understanding of PPN stimulation we construct a computational model for the PPN Type I neurons in a network

Monitoring the Paraguayan epidemiological dengue surveillance system (2009-2011) using Benford's law

Introduction: Dengue is the most widespread arbovirus worldwide. In Paraguay, it reappeared in 1988-1989, with one of the largest epidemic outbreaks occurring in 2011. Objective: To evaluate the performance of the dengue epidemiological surveillance system in Paraguay between 2009 and 2011. Materials and methods: We conducted an ecological study with secondary epidemiological surveillance data. We analyzed notified cases of the disease based on the distribution expected by Benford's law. To this end, we used the first and second digits from the global records stratified by region, season, population density, indicators of housing conditions and heads of cattle. Results: The epidemiological surveillance system performed better during non-epidemic periods and in the states with better housing conditions and fewer heads of cattle. Conclusion: Given that a difference in the performance existed, we recommended that the system remains operating at the same high alert level even during periods when fewer cases are expected. The technology used by the method proposed to monitor the notification of cases is easy to transfer to operational staff

Educational Innovation with Learning Networks: Tools and Developments

Professional Development is ill served by traditional ways of learning. It can profit from a Learning Networks approach, which emphasizes logistic, content and didactic flexibility. Learning Networks are online, social networks that have been de- signed and tooled to foster informal learning. Three European projects are discussed – idSpace, LTfLL, Handover - which have developed tools befitting networked learning. Each in its own way, the projects illustrate the benefits of a networked learning ap- proach. This goes for all three flexibilities but in particular for the need to be didactical- ly flexible. Finally, it is argued that formal education could profit from the tools dis- cussed

Vacancy-assisted domain-growth in asymmetric binary alloys: a Monte Carlo study

A Monte Carlo simulation study of the vacancy-assisted domain-growth in asymmetric binary alloys is presented. The system is modeled using a three-state ABV Hamiltonian which includes an asymmetry term, not considered in previous works. Our simulated system is a stoichiometric two-dimensional binary alloy with a single vacancy which evolves according to the vacancy-atom exchange mechanism. We obtain that, compared to the symmetric case, the ordering process slows down dramatically. Concerning the asymptotic behavior it is algebraic and characterized by the Allen-Cahn growth exponent x=1/2. The late stages of the evolution are preceded by a transient regime strongly affected by both the temperature and the degree of asymmetry of the alloy. The results are discussed and compared to those obtained for the symmetric case.Comment: 21 pages, 9 figures, accepted for publication in Phys. Rev.

Design of the POINT study: Pharmacotherapy Optimisation through Integration of a Non-dispensing pharmacist in a primary care Team (POINT)

__Background:__ In the Netherlands, 5.6 % of acute hospital admissions are medication-related. Almost half of these admissions are potentially preventable. Reviewing medication in patients at risk in primary care might prevent these hospital admissions. At present, implementation of medication reviews in primary care is suboptimal: pharmacists lack access to patient information, pharmacists are short of clinical knowledge and skills, and working processes of pharmacists (focus on dispensing) and general practitioners (focus on clinical practice) match poorly. Integration of the pharmacist in the primary health care team might improve pharmaceutical care outcomes. The aim of this study is to evaluate the effect of integration of a non-dispensing pharmacist in general practice on the safety of pharmacotherapy in the Netherlands. __Methods:__ The POINT study is a non-randomised controlled intervention study with pre-post comparison in an integrated primary care setting. We compare three different models of pharmaceutical care provision in primary care: 1) a non-dispensing pharmacist as an integral member of a primary care team, 2) a pharmacist in a community pharmacy with a predefined training in performing medication reviews and 3) a pharmacist in a community pharmacy (care as usual). In all models, GPs remain accountable for individual medication prescription. In the first model, ten non-dispensing clinical pharmacists are posted in ten primary care practices (including 5 – 10 000 patients each) for a period of 15 months. These non-dispensing pharmacists perform patient consultations, including medication reviews, and share responsibility for the pharmaceutical care provided in the practice. The two other groups consist of ten primary care practices with collaborating pharmacists. The main outcome measurement is the number of medication-related hospital admissions during follow-up. Secondary outcome measurements are potential medication errors, drug burden index and costs. Parallel to this study, a qualitative study is conducted to evaluate the feasibility of introducing a NDP in general practice. __Discussion:__ As the POINT study is a large-scale intervention study, it should provide evidence as to whether integration of a non-dispensing clinical pharmacist in primary care will result in safer pharmacotherapy. The qualitative study also generates knowledge on the optimal implementation of this model in primary care. Results are expected in 2016

Controversy and consensus on a clinical pharmacist in primary care in the Netherlands

Background Controversy about the introduction of a non-dispensing pharmacist in primary care practice hampers implementation. Objective The aim of this study is to systematically map the debate on this new role for pharmacists amongst all stakeholders to uncover and understand the controversy and consensus. Setting: Primary health care in the Netherlands. Method Q methodology. 163 participants rank-ordered statements on issues concerning the integration of a non-dispensing pharmacist in primary care practice. Main outcome measure: Stakeholder perspectives on the role of the non-dispensing pharmacist and pharmaceutical care in primary care. Results This study identified the consensus on various features of the non-dispensing pharmacist role as well as the financial, organisational and collaborative aspects of integrating a non-dispensing pharmacist in primary care practice. Q factor analysis revealed four perspectives: “the independent community pharmacist”, “the independent clinical pharmacist”, “the dependent clinical pharmacist” and “the medication therapy management specialist”. These four perspectives show controversies to do with the level of professional independency of the non-dispensing pharmacist and the level of innovation of task performance. Conclusion Despite the fact that introducing new professional roles in healthcare can lead to controversy, the results of this Q study show the potential of a non-dispensing pharmacist as a pharmaceutical care provider and the willingness for interprofessional collaboration. The results from the POINT intervention study in the Netherlands will be an important next step in resolving current controversies

Low Surface Recombination in Hexagonal SiGe Alloy Nanowires:Implications for SiGe-Based Nanolasers

Monolithic integration of silicon-based electronics and photonics could open the door toward many opportunities including on-chip optical data communication and large-scale application of light-based sensing devices in healthcare and automotive; by some, it is considered the Holy Grail of silicon photonics. The monolithic integration is, however, severely hampered by the inability of Si to efficiently emit light. Recently, important progress has been made by the demonstration of efficient light emission from direct-bandgap hexagonal SiGe (hex-SiGe) alloy nanowires. For this promising material, realized by employing a nanowire structure, many challenges and open questions remain before a large-scale application can be realized. Considering that for other direct-bandgap materials like GaAs, surface recombination can be a true bottleneck, one of the open questions is the importance of surface recombination for the photoluminescence efficiency of this new material. In this work, temperature-dependent photoluminescence measurements were performed on both hex-Ge and hex-SiGe nanowires with and without surface passivation schemes that have been well documented and proven effective on cubic silicon and germanium to elucidate whether and to what extent the internal quantum efficiency (IQE) of the wires can be improved. Additionally, time-resolved photoluminescence (TRPL) measurements were performed on unpassivated hex-SiGe nanowires as a function of their diameter. The dependence of the surface recombination on the SiGe composition could, however, not be yet addressed given the sample-to-sample variations of the state-of-the-art hex-SiGe nanowires. With the aforementioned experiments, we demonstrate that at room temperature, under high excitation conditions (a few kW cm–2), the hex-(Si)Ge surface is most likely not a bottleneck for efficient radiative emission under relatively high excitation conditions. This is an important asset for future hex(Si)Ge optoelectronic devices, specifically for nanolasers