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Abstract Mangroves, coastal forests under the influence of tides, are known to be very resilient when they face natural disturbances such as storms or tsunami. While they provide several ecological services, they are threatened by many anthropic pressures. The aim of this study was to assess and to compare the stability of two mangrove fringes defined by contrasted set of natural constraints and exposed to pretreated domestic wastewaters discharges. The in situ experimental system set up in Mayotte Island (Indian Ocean) allowed us to determine both the short-term (2 years) and the long-term (9 years) resistance and the resilience. We focused on vegetation and crabs, an essential component of mangroves fauna. Wastewater discharges induced increases in tree coverage, leaves productivity and pigment content, and a decrease in crab diversity and density. Within 2 years after the release of the disturbance, several parameters reach back control values indicating fast resilience. Our results notably emphasized the high stability of the mangrove fringe dominated by Rhizophora mucronata trees, which was both more resistant and more resilient. This makes this fringe more suitable for application purposes, such as outfall for domestic wastewaters treatment plants. Highlights • The stability (resistance and resilience) of two mangrove zones was studied. • Mangroves were exposed at short and long term to anthropogenic disturbance. • Vegetation growth was enhanced and crab populations were rapidly modified. • Crab and vegetation showed partial resilience within 2 years. • One zone was much more stable than the other one. [ABSTRACT FROM AUTHOR]

It was hypothesized that mangroves, tropical wetlands, could be used for the finishing treatment of domestic wastewaters. Our aim was to determine if a nutrient-stressed mangrove could tolerate long-term discharges of pretreated wastewater (PW). Since 2008, in an in situ experimental system set up in Mayotte Island (Indian Ocean), domestic PW are discharged into two impacted areas (675 m 2 ) dominated by different species of mangrove trees. Anthropogenic inputs during > 4.5 years led to an increase in vegetation growth associated with an increase in leaf pigment content, leaf surface and tree productivity. A marked increase in tree mortality was observed. There was no effect on crabs and meiofauna densities, but significant modifications of community structures. These effects may be directly linked to PW inputs, or indirectly to the modifications of the environment associated with higher tree growth. However, our results indicate that there was no major dysfunction the ecosystem. [ABSTRACT FROM AUTHOR]

We propose a nonlinear image encryption system using Arnold transform (ART) and a fully-phase encoded images as inputs to a nonzero-order joint transform correlator (JTC) in the fractional Fourier transform (FRFT) domain. Unlike other reported works, the fully-phase image along with two random-phase masks (RPMs) are introduced directly without linear phase modulation at the input plane of the JTC where the FRFT modulates this joint input image and produces the joint fractional power distribution (JFPD) at the output plane. It will be demonstrated that using modulating inputs in the optical setup makes the decryption scheme prone to error and leads to retrieving image failure. Further, a shifted-phase encoded key mask is applied in this proposal to achieve the non-zero order JFPD , which is adjusted by a nonlinear operation to guarantee a securely and high-quality retrieved ciphertext image. Furthermore, the proposed encryption scheme has four security keys: (i) two-random-phase masks, (ii) an ART frequency parameter, and (iii) a fractional order of the FRFT. It will be demonstrated that the decryption process is very sensitive to small variations of the ART frequency parameter, the fractional order of the FRFT, and the RPM. The cryptanalysis shows that the proposed encryption system is very invulnerable to Chosen plaintext (CPA), known plaintext (KPA), ciphertext only (COA) and brute force attacks. In addition, the robustness of the proposed scheme against noise and occlusion is presented using computer simulations. [ABSTRACT FROM AUTHOR]

Abstract: The need for increasingly high-speed digital optical systems and optical processors demands ultra-fast all-optical logic and arithmetic units. In this paper, we combine the attractive and powerful parallelism property of the modified signed-digit (MSD) number representation with the ultra-fast all-optical switching property of the semiconductor optical amplifier and Mach–Zehnder interferometer (SOA–MZI) to design and implement all-optical MSD adder/subtracter circuits. Non-minimized and minimized techniques are presented to design and realize efficient circuits to perform arithmetic operations. Several all-optical circuits’ designs are proposed with the objective to minimize the number of the SOA–MZI switches, the time delay units in the adders, and other optical elements. To use the switching property of the SOA–MZI structure, two bits per digit binary encoding for each of the trinary MSD digits are used. The proposed optical circuits will be very helpful in developing hardware modules for optical digital computing processors. [ABSTRACT FROM AUTHOR]

Simulations of the reaction between the free radical ⋅OH and each of the two saccharides of hyaluronan were investigated using ab initio (Hartree–Fock and DFT) computations. The five radicals of GlcA in monoanionic and sodium compensated forms (arising from the hydrogen abstraction at C1, C2, C3, C4 and C5 sites) and the six radicals of GlcNAc (arising from the hydrogen abstraction at C1, C2, C3, C4, C5 and C6 sites) were studied at the level UHF/6-31G* and UMPW1PW91/6-31G*. The quantum properties of the full optimized conformations of these radicals are presented. Results on electronic energies, frontier orbitals and spin densities are discussed. UHF and DFT computations lead to an atomic spin density α(↑) concentrated essentially in a π-like orbital localized on each carbon radical of GlcA and GlcNAc. The thermochemistry of the reaction between ⋅OH and the different sites of hydrogen abstraction on sodium compensated GlcA or GlcNAc is presented at the level MPW1PW91/6-31G*. Finally, the simulation of the hydrogen abstraction at the C5 position of GlcA in hyaluronan by the free radical hydroxyl was conducted using the supermolecule (GlcNAc–GlcA–GlcNAc+⋅OH) and an optimization at the UHF/6-31G* level. [Copyright &y& Elsevier]

Presents information pertaining to computer and electrical engineering, highlighting a study in which symmetrical and non-symmetrical parallel recoding algorithms for the modified signed-digit numbers are suggested. How digital operations are implemented in digital computations; How arithmetic operations can be realized; Relationship between modified signed-digit and the binary number process.

This study aims to assess the methodological quality of budget impact analysis of orphan drugs with a view to determine how the accuracy and reliability of such studies can be enhanced. This initial review generated fourteen articles on budget impact analysis of individual orphan drugs and seven articles focused on budget impact analysis of a combination of orphan drugs. Future studies should include accurate comparative analysis with and without orphan drug(s), have a defined time horizon, explore the budget impact on costs other than related to drugs, and conduct extensive scenario analyses. [Extracted from the article]

We report the case management of a patient with a methicillin-resistant Staphylococcus aureus intramyocardial abscess adjacent to a previously grafted native right coronary artery. The diagnosis was eventually established by obtaining a gallium scan. This case illustrates the need for maintaining a wide-ranging view of potential causes of bacteremia after cardiac surgery, especially in elderly patients with multiple comorbidities. [ABSTRACT FROM AUTHOR]

Repair of an aortic root aneurysm using a composite graft is sometimes complicated by proximal suture line bleeding, which may be very difficult to control. We adopted a previously described technique of “double overlap” sutures on the annulus and the prosthetic cuff, which has virtually eliminated this complication. [Copyright &y& Elsevier]

Molluscan remains from archaeological contexts have the potential to provide information related to a range of issues, including but not limited to settlement and economic structures, and local environmental conditions. Shell deposits are ubiquitous along the eastern African coast and offshore islands, with previous archaeological research highlighting the prevalence of these deposits in conjunction with providing some discussion on the variable contribution or role of molluscs within the economy. In general, marine molluscs have been viewed as a secondary or fall-back resource with largely opportunistic harvesting in the intertidal zone. In addition, there is a general expectation that there would be significant variability in exploitation depending on settlement structure, the availability of domesticates, and with status differences. With few exceptions, however, the scale and resolution of archaeomalacological analyses across the broader region have tended to be relatively coarse, making it difficult to adequately assess these interpretations. Here we consider these issues based on detailed analyses of the sites of Unguja Ukuu and Fukuchani situated on the island of Unguja (Zanzibar), providing an assessment of the relative importance of the exploited taxa and ecological niches, in combination with species richness and diversity. These analyses provide a comparative framework for other sites in the region, and a baseline understanding of human interactions with coastal environments through molluscan exploitation. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The study investigated physical fitness characteristics of elite Taekwondo (TKD) players as well as their heart rate (HR) response and blood lactate concentration changes during TKD specific exercises and simulated competition. Methods: Anaerobic and aerobic power has been evaluated in eight elite TKD players (age: 20±1 years, body mass: 70.8±6 kg, Ht: 179.9±4 cm). We also measured heart rate and blood lactate concentration during competition and specific-exercises (front kicks during 10 s, 1 and 3 min). Results: Maximum oxygen uptake (VO2max) and peak anaerobic power (Wpeak) averaged 56.22±2.57 ml min–1 kg–1 and 12.1±1.7 W kg–1, respectively. HR and blood lactate [La] concentrations increased significantly during competition (F =19.4, P <0.001; F =21.3, P <0.001) compared to the resting value. HR and [La] values were significantly correlated with those measured during 10 s (R =0.85, P <0.05 and R =0.79, P <0.05, respectively) and 3-min specific exercises (R =0.95, P <0.01 and R =0.76, P <0.05). Conclusions: TKD requires high levels of both aerobic and anaerobic physical fitness. The correlation between specific exercises and competition is of practical interest for TKD players and trainers. [Copyright &y& Elsevier]