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Open access

Md Meftahul Ferdaus, Sreenatha G. Anavatti, Matthew A. Garratt and Mahardhika Pratama

Abstract

Advanced and accurate modelling of a Flapping Wing Micro Air Vehicle (FW MAV) and its control is one of the recent research topics related to the field of autonomous MAVs. Some desiring features of the FW MAV are quick flight, vertical take-off and landing, hovering, and fast turn, and enhanced manoeuvrability contrasted with similar-sized fixed and rotary wing MAVs. Inspired by the FW MAV’s advanced features, a four-wing Nature-inspired (NI) FW MAV is modelled and controlled in this work. The Fuzzy C-Means (FCM) clustering algorithm is utilized to construct the data-driven NIFW MAV model. Being model free, it does not depend on the system dynamics and can incorporate various uncertainties like sensor error, wind gust etc. Furthermore, a Takagi-Sugeno (T-S) fuzzy structure based adaptive fuzzy controller is proposed. The proposed adaptive controller can tune its antecedent and consequent parameters using FCM clustering technique. This controller is employed to control the altitude of the NIFW MAV, and compared with a standalone Proportional Integral Derivative (PID) controller, and a Sliding Mode Control (SMC) theory based advanced controller. Parameter adaptation of the proposed controller helps to outperform it static PID counterpart. Performance of our controller is also comparable with its advanced and complex counterpart namely SMC-Fuzzy controller.

Open access

Elena Dück and Robin Lucke

Abstract

After the November 2015 terror attacks in Paris, the French government reacted swiftly by declaring a state of emergency. This state of emergency remained in place for over two years before it was ended in November 2017, only after being replaced by the new anti-terror legislation. The attacks as well as the government’s reactions evoked parallels to 9/11 and its aftermath. This is a puzzling observation when taking into consideration that the Bush administration’s reactions have been criticized harshly and that the US ‘War on Terror’ (WoT) was initially considered a serious failure in France. We can assume that this adaption of the discourse and practices stems from a successful establishment of the WoT macro-securitization. By using Securitization Theory, we outline the development of this macro-securitization by comparing its current manifestation in France against the backdrop of its origins in the US after 9/11. We analysed securitizing moves in the discourses, as well as domestic and international emergency measure policies. We find extensive similarities with view of both; yet there are diff ering degrees of securitizing terrorism and the institutionalisation of the WoT in the two states. This suggests that the WoT narrative is still dominant internationally to frame the risk of terrorism as an existential threat, thus enabling repressive actions and the obstruction of a meaningful debate about the underlying problems causing terrorism in the first place.

Open access

Piotr Boguta, Dariusz Juchnowicz, Paulina Wróbel-Knybel, Agnieszka Biała-Kędra and Hanna Karakuła-Juchnowicz

Abstract

Introduction: Warfarin has been considered as a “gold standard” in the prevention and treatment of thromboembolic events since 1954. Since the introduction of direct oral anticoagulants in the last few years (NOAC-Non-Vitamin K antagonist Oral Anticoagulants) prescriptions volume for apixaban, edoxaban, dabigatran and rivaroxaban have been gradually surpassing warfarin. The benefits include: anticoagulation from day one, fixed daily dosing, elimination for the need of international normalised ratio (INR) monitoring, fewer interactions with food and co-administered medicines with reduced risk of bleeding and better overall life quality.

Objectives: Assessing evidence for the safe use of Non-vitamin K Oral Anticoagulants (NOAC) with Selective Serotonin Reuptake Inhibitors (SSRI) and Serotonin and Noradrenaline Reuptake Inhibitors (SNRI).

Method: Review of literature published between 2014 and 2016 was made using the key words: Selective Serotonin Reuptake Inhibitor, Serotonin and Noradrenaline Reuptake Inhibitors, apixaban, dabigatran, edoxaban, rivaroxaban, bleeding, interaction, depression with time description from 2014 to 2018. Evidence within the literature was then compared with guidelines from the National Institute for Health and Care Excellence (UK), British National Formulary (UK), Clinical Excellence Commission (Australia), Thrombophilia and Anticoagulation Clinic (USA) and Summaries of Product Characteristics (SPC).

Results: 1. Serotonin plays a critical role in maintaining homeostasis. Use of SSRI/SNRI compromises its platelet reuptake increasing risk of bleeding.

2. Increased tolerability and safety of NOAC over Warfarin, although caution is advised when NOAC is used with SSRI/SNRI with less evidence suggesting pharmacodynamic interactions.

3. It is not recommended to use NOAC with strong CYP and P-gp inhibitors.

Conclusions: With limited literature evidence, caution is advised when co-prescribed NOACs with SSRI/SNRI, especially with other cofactors and interacting medicines further increasing risk of bleeding.

Open access

Mariela Patrignani, Guillermina A. Fagúndez and Cecilia E. Lupano

Abstract

Honey floral origin is determined by the harversting region, but anthropogenic factors as agriculture expansion might modify the environmental flora and consequently honey floral origin. Argentina is one of the most important honey producers worldwide which, since the 1990s, has undergone an important agriculture transformation by the adoption of transgenic crops like soybean (Glycine max). However, little is known about the effects of this anthropogenic activity on the floral origin of honey or the statistical tools that could be used to analyse it. The objective of the present study was to evaluate the impact that these environmental modifications have on the pollen spectrum of honey. In order to achieve this, thirty-two samples of blossom honey were collected from three different ecoregions of the Buenos Aires province: Parana Delta and Islands, Espinal, and Pampa, in two different years: 1999 and 2014. The pollen spectrum of honey samples was determined and the data obtained was analysed with multivariate statistical techniques. It could be concluded that the pollen composition of honeys from different ecoregions has significantly changed in the past years because of agriculture expansion and adaptation of transgenic crops (p=0.007). Honey samples harvested in 1999 were characterized by high values of Helianthus annuus, while in 2014 an important presence of Eryngium sp., Gleditsia triacanthos, Baccharis type, Trifolium sp. and Glycine max was observed. The present results show that honey palynological results and multivariate statistical analysis could be used as a preliminary attempt to evaluate environmental modifications.

Open access

Jakub Siembida and Kaja Karakuła

Abstract

Introduction: Gamma-hydroxybutyric acid (GHB) is commonly known as a recreation drug or the so-called “date rape drug”. It is also used in medicine to treat narcolepsy and alcohol addiction. GHB has an affinity for two types of receptors: GABAB and the relatively recently discovered GHB receptors. GHB receptors were first cloned in 2003 in mice and then in 2007 in humans. So far, evidence has been presented for their impact on dopaminergic transmission, which may imply that they play a role in the pathogenesis of diseases such as schizophrenia. At the same time, it has been demonstrated that benzamide antipsychotic drugs have an affinity for GHB receptors, which is why it is postulated that some of the effects of these drugs may result precisely from this affinity.

Aim: The study presents the current state of knowledge about GHB receptors and their potential role in the pathogenesis of schizophrenia, and discusses drugs which show an affinity for this receptor.

Material and method: The literature review was based on a search of articles indexed between 1965 and 2018 in Medline, Google Scholar, ScienceDirect and Research Gate databases. The following search terms were used: GHB receptor, GHB, sulpiride, and amisulpride.

Result and discussion: 1. It is possible that GHB receptors are involved in the pathogenesis of schizophrenia, although more research is needed in this area.

2. Part of the effects of some benzamide antipsychotic drugs (such as amisulpride) may be due to their affinity for GHB receptors.

Open access

Rogério M. D. O. Alves, Ana M. Waldschmidt, Joana F. Paixão, Daiane R. Santos and Carlos A. L. Carvalho

Abstract

The bees of the genus Cephalotrigona (locally known as “mombucas”) play a key role in natural environments but their bioecological features, required to design proper management and conservation strategies, are scarce in most species. Thus, the goal of the present study was to map the occurrence sites of C. capitata in the state of Bahia, northeastern Brazil, and to provide useful information about nest architecture to their technical management. This species was recorded in fifteen municipalities in Bahia, totaling forty-one nests. The range of C. capitata varied from locations at sea level to seasonal ombrophilous forests at an altitude of 600m high. The nests were built in trees with a mean diameter of 19.8 ±3.0 cm. The nest architecture was similar to that reported in other stingless bee species, with a variation in analyzed parameters. The thermoregulation was more efficient in highly populated boxes. The present results can be used for the conservation and management of this species, which represents a potential source of income for local farmers.

Open access

Divya Sharma, Sapna Katna, Reena Sharma, Bachittar S. Rana, Harish K. Sharma, Vinay Bhardwaj and Avinash Chauhan

Abstract

Apis mellifera colonies were sampled for over twelve months to study the Nosema infection in different apiaries of Himachal Pradesh, India. We found that the infection incidence was highest in the winter season (48.40 %) followed by autumn and rainy months. The infection was diagnosed conventionally through the microscopic analysis detection of Nosema species spores. However, with the recent findings that both N. ceranae and N. apis affect western honey bees, more sensitive and species specific molecular techniques are required that reliably differentiate between species of microsporidia. Therefore, molecular studies were conducted to precisely differentiate between Nosema species infecting honeybee colonies in India. Species specific multiplex PCR amplification using previously reported primers derived from 16S rRNA fragments were performed in a single reaction mixture. A single diagnostic band size of only 143 bp for N. ceranae was observed in the agarose gel. Furthermore, a diagnostic band size of 252 bp was observed with primer NoS, thus reconfirming the presence of N. ceranae. This study appears to be the first to report the detect of N. ceranae species from India in samples of A. mellifera.