Conservation in conflict: Illegal drugs versus habitat in the Americas

About the book: State of the Wild is a biennial series that brings together international conservation experts and writers to discuss emerging issues in the conservation of wildlife and wild places. Each volume in the series combines evocative writings with a fascinating tour of conservation news highlights and vital statistics from around the world. One-third of each volume focuses on a topic of particular concern to conservationists working to protect wildlife and our last wild places. This 2008–2009 edition considers the integration of wildlife health, ecosystem health, human health, and the health of domestic animals—a “One World–One Health” approach to disease and conservation. This focus is complemented with essays clustered into sections that address other key issues—conservation of species; conservation of wild places; people, culture, and conservation; and the art and practice of conservation. Essays cover a broad range of topics, from restoring biodiversity on the prairies to mapping the state of the oceans to the conservation impacts of lawlessness and coca cultivation in Colombia. Essay contributions come from people directly involved in on-the-ground conservation efforts and offer a unique and valuable perspective on often-overlooked topics. State of the Wild’s accessible approach educates a wide range of audiences while at the same time presenting leading-edge scientific overviews of hot topics in conservation. Uniquely structured with magazine-like features up front, conservation news in the middle, and essays from eminent authors and experienced scientists throughout, this landmark series is an essential addition to any environmental bookshelf

A novel approach to bioelectrical impedance plethysmography for the assessment of arterial and venous circulatory problems in the forearm

Peripheral vascular disease (PVD) and/or peripheral arterial disease (PAD) are sicknesses known to inadequate delivery of either arterial or venous blood towards the extremities. Such sickness may trigger complications owing to the lack of transport of oxygen and nutrients, thus causing hypoxic events that may eventually prompt to ischaemic tissue or even the loss of the compromised limb. One of the most prominent indicators of prosperous health is blood volume and flow. The basic information within these health parameters may show cardiovascular problems or the advance of further complications related to other diseases like diabetes. In clinical setting, there effective methods to measure these parameters like Doppler ultrasound, photoplethysmography or venous occlusion plethysmography. These methods take measurements from either single vessels and/or small volume of tissue. However, it is difficult to establish a relation between the obstruction of arterial and/or venous circulation and the amount of blood received by the tissue. Bioelectrical impedance plethysmography (iPG) measures blood changes by driving a small amount of AC current into the body and after measuring the potential created by fluids flowing through tissue. This technique apart from taking measures within defined volumes of tissue, it is easy to use as only needs four electrodes on the skin. Hence, a bespoken bioelectrical impedance device including hardware and software was built ready to measure changes in blood volume/flow in the upper limbs. The system was assessed in an in-vivo controlled environment with 8 participants. The blood flow towards their left arms was altered by constricting the upper arm with a cuff at three levels: 1) below venous pressure 2) amongst venous and arterial pressure and 3) during total occlusion. Simultaneously, measurements from various instruments like ECG, Doppler ultrasound, laser Doppler flowmetry and PPG were taken and compared to the measurements obtained from the iPG instrument and defining its correlation with the impedimetric signal. The results from the experiments showed that the bioelectrical impedance signal changed in basal and arterial pulses showing specific characteristics for each kind of occlusion. The data indicated that it is possible to differentiate between a venous and arterial occlusion by examining both components of the impedance signal. The impedance during venous occlusion dropped in average 0.658±0.230% from the baseline. On the other hand, during arterial occlusion the base impedance dropped in a higher rate approximately 1.13±04.82%, indicating a differentiator during both type of blood flow disruption. Furthermore, the impedance plethysmography waveform morphology also reshaped during these occlusive periods. The whole waveform during artificial venous obstruction increased in magnitude, the systolic peak rose 31.80%, the dicrotic notch 47.73% and the diastolic point 31.92%, where the value of the latter was higher than the dicrotic notch point. In contrast, in the time of partial arterial occlusion the waveform also increased in size at all these points, but its shape was altered. The impedance magnitude at the diastolic point went below the ones at the dicrotic notch. These fluctuations provided additional further information that it might be possible to differentiate amongst venous and arterial occlusions. By consolidating the data obtained by the iPG device, it is possible to produce an index ratio between the basal impedance and these three reference points which may help to identify early circulatory problems in the arterial and/or venous systems

Simpatectomía toracoscópica: una revisión de la literatura

INTRODUCTION: Since its first description by Kux in 1954, the thoracic endoscopic (thoracoscopic) sympathectomy has rendered the open techniques obsolete in the treatment of the hyperhidrosis and other sympathetic-related diseases. AIM. The goal of this article is to present a critical review of the current indications, results and complications of the endoscopic thoracic sympathectomy. MATERIAL AND METHODS: An extensive search and review of published papers on the thoracoscopic sympathectomy was undertaken. RESULTS: The thoracoscopic sympathectomy has evolved as a therapeutic choice in patients with focal hyperhidrosis, pain syndromes and peripheral vascular disorders, particularly. The results, recurrences and complications are similar to the previously established open procedures; nevertheless, the morbidity, the hospital stay and the time to return to activities of daily living are substantially reduced. The highest success and satisfaction rates (over 95%) were observed among patients treated for focal hyperhidrosis. CONCLUSIONS: The success and complication rates of thoracoscopic sympathectomy are comparable to those of open techniques, with an easier postoperative period and an earlier return to labor and daily living

Novel scheme for a PCM-based cold energy storage system. Design, modelling, and simulation

This paper studies the design and dynamic modelling of a novel thermal energy storage (TES) system combined with a refrigeration system based on phase change materials (PCM). Cold-energy production supported by TES systems is a very appealing field of research, since it allows flexible cold-energy management, combining demand fulfilment with cost reduction strategies. The paper proposes and compares two different simulation models for a cold-energy storage system based on PCM. First, a continuous model is developed, the application of which is limited to decoupled charging/discharging operations. Given such conditions, it is a relatively precise model, useful for the tuning of the TES parameters. The second proposed model is a discrete one, which, despite implementing a discrete approximation of the system behaviour, allows to study more general conditions, such as series of partial charging/discharging operations. Simulation results of both models are compared regarding decoupled charging/discharging operations, and the ability of the discrete model to represent more realistic partial operations is analysed.Comment: 48 pages, 14 figures. Postprint of the final published wor

Dilaton thin-shell wormholes supported by a generalized Chaplygin gas

In this article, we construct spherical thin-shell wormholes with charge in dilaton gravity. The exotic matter required for the construction is provided by a generalized Chaplygin gas. We study the stability under perturbations preserving the symmetry. We find that the increase of the coupling between the dilaton and the electromagnetic fields reduces the range of the parameters for which stable configurations are possible.Comment: 14 pages, 6 figures. v3: typos correcte

MINLP-based hybrid strategy for operating mode selection of TES-backed-up refrigeration systems

This brief deals with the satisfaction of the daily cooling demand by a hybrid system that consists of a vapour-compression refrigeration cycle and a thermal energy storage (TES) unit, based on phase change materials. The addition of the TES tank to the original refrigeration plant allows to schedule the cooling production regardless of the instantaneous demand, given that the TES tank can store cold energy and release it whenever deemed appropriate. The scheduling problem is posed as an optimization problem based on mixed-integer non-linear programming (MINLP), since it includes both discrete and continuous variables. The latter corresponds to the references on the main cooling powers involved in the problem (cooling production at the evaporator and TES charging/discharging), whereas the discrete variables define the operating mode scheduling. Therefore, in addition to the hybrid features of the physical plant, a hybrid optimal control strategy is also proposed. A receding horizon approach is applied, similar to model predictive control (MPC) strategies, while economic criteria are imposed in the objective function, as well as feasibility issues. The TES state estimation is also addressed, since its instantaneous charge ratio is not measurable. The proposed strategy is applied in simulation to a challenging cooling demand profile and the main advantages of the MINLP-based strategy over a non-linear MPC-based scheduling strategy previously developed are highlighted, regarding operating cost, ease of tuning, and ability to adapt to cooling demand variations.Comment: 22 pages, 11 figures. Postprint of the final published wor

A Theoretical Construction of Thin Shell Wormhole from Tidal Charged Black hole

Recently, Dadhich et al [ Phys.Lett.B 487, 1 (2000)] have discovered a black hole solution localized on a three brane in five dimensional gravity in the Randall-Sundrum scenario. In this article, we develop a new class of thin shell wormhole by surgically grafting above two black hole spacetimes. Various aspects of this thin wormhole are also analyzed.Comment: 14 pages, 6 figures, Accepted in Gen.Rel.Gra