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Delay sensitive and power-aware SMDP-based connection admission control mechanism in cognitive radio sensor networks
© 2017 Elsevier B.V. Due to the opportunistically resource usage of users in cognitive radio sensor networks (CRSNs), the availability of network resources is highly variable. Therefore, admission control is an essential mechanism to manage the traffic of cognitive radio users in order to satisfy the quality of service (QoS) requirements of applications. In this study, a connection admission control (CAC) mechanism is introduced to satisfy the requirements of delay sensitivity and power consumption awareness. This proposed mechanism is modeled through a semi Markov decision process (SMDP) and a linear programming problem is derived with the aim of obtaining the optimal policy to control the traffic of CRSNs and achieving maximum reward. The number of required channels at each network state is estimated through a graph coloring approach. An end to end delay constraint is defined for the optimization problem which is inspired from Kleinrock independence approximation. Furthermore, a power-aware weighting method is proposed for this mechanism. We conduct different simulation-based scenarios to investigate the performance of the proposed mechanism. The experimental results demonstrate the efficiency of this SMDP-based mechanism in comparison to the last CAC mechanism in CRSNs
Anacin induced adverse drug reaction: A case report
Anacin; a brand of aspirin tablets (containing 300mg acetylsalicylic acid), is a widely used analgesics. It is recognized as one of the oldest brands of pain relievers. Its primary content is acetylsalicylic acid. Here we report a case of a 26-year old woman (64 kg in weight and 1.41m in height) who presented with adverse drug reaction secondary to Anacin ingestion following gum pain from fish bone injury. About 30mins after ingesting the drug, she presented with headache, excessive lacrimal gland secretion and facial swelling. Considering these presentations by inference, Anacin may have the potential to cause severe adverse drug reaction in some individuals. Hence, care should be taken by doctors, pharmacist and other health care providers when prescribing and monitoring patients placed on this medication. Additionally, a detailed history should be taken prior to prescribing and appropriate reporting should be made to relevant health authorities when such severe reactions are observed.Keyword: Anacin, adverse drug reaction, pain, Acetylsalicylic acid
Voting 'against all' in postcommunist Russia
Since the early 1990s voters in Russia (and most of the other post-Soviet republics) have been offered
the opportunity to vote ‘against all’ parties and candidates. Increasing numbers have done so. The
evidence of two post-election surveys indicates that ‘against all’ voters are younger than other voters,
more urban and more highly educated. They do not reject liberal democracy, but are critical of the
contemporary practice of Russian politics and find no parties that adequately reflect their views. With
the ending of the ‘against all’ facility in 2006 and other changes in the Russian electoral system under
the Putin presidency, levels of turnout are likely to fall further and the protest vote will seek other
outlets within or outside the parliamentary system
Structural elucidation of unknowns: a spectroscopic investigation with an emphasis on 1D and 2D nuclear magnetic resonance spectroscopy
Nuclear Magnetic Resonance (NMR) spectroscopy is a widely used technique for structural elucidation. It is often used in conjunction with other complimentary analytical techniques such as infra-red (IR) and mass spectrometry (MS) to completely assign the chemical structure of molecules. For undergraduate students, gaining familiarity with NMR is often difficult as they rarely have the opportunity to collect this data for themselves; often they are just provided with spectra to interpret. We have developed an experiment that tasks students with obtaining 1D and 2D 1H NMR data of two unknowns, and then using 13C NMR, CHN elemental microanalysis, MS and IR data, to elucidate fully their two structures. The experiment provides students with an experiential learning opportunity for 1H NMR whilst also developing and strengthening their structural elucidation skills
Cardy and Kerr
The Kerr/CFT correspondence employs the Cardy formula to compute the entropy
of the left moving CFT states. This computation, which correctly reproduces the
Bekenstein--Hawking entropy of the four-dimensional extremal Kerr black hole,
is performed in a regime where the temperature is of order unity rather than in
a high-temperature regime. We show that the comparison of the entropy of the
extreme Kerr black hole and the entropy in the CFT can be understood within the
Cardy regime by considering a D0-D6 system with the same entropic properties.Comment: 20 pages; LaTeX; JHEP format; v.2 references added, v.3 Section 4
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Femtosecond nonlinear ultrasonics in gold probed with ultrashort surface plasmons
Fundamental interactions induced by lattice vibrations on ultrafast time
scales become increasingly important for modern nanoscience and technology.
Experimental access to the physical properties of acoustic phonons in the THz
frequency range and over the entire Brillouin zone is crucial for understanding
electric and thermal transport in solids and their compounds. Here, we report
on the generation and nonlinear propagation of giant (1 percent) acoustic
strain pulses in hybrid gold/cobalt bilayer structures probed with ultrafast
surface plasmon interferometry. This new technique allows for unambiguous
characterization of arbitrary ultrafast acoustic transients. The giant acoustic
pulses experience substantial nonlinear reshaping already after a propagation
distance of 100 nm in a crystalline gold layer. Excellent agreement with the
Korteveg-de Vries model points to future quantitative nonlinear femtosecond
THz-ultrasonics at the nano-scale in metals at room temperature
Do Natural Proteins Differ from Random Sequences Polypeptides? Natural vs. Random Proteins Classification Using an Evolutionary Neural Network
Are extant proteins the exquisite result of natural selection or are they random sequences slightly edited by evolution? This question has puzzled biochemists for long time and several groups have addressed this issue comparing natural protein sequences to completely random ones coming to contradicting conclusions. Previous works in literature focused on the analysis of primary structure in an attempt to identify possible signature of evolutionary editing. Conversely, in this work we compare a set of 762 natural proteins with an average length of 70 amino acids and an equal number of completely random ones of comparable length on the basis of their structural features. We use an ad hoc Evolutionary Neural Network Algorithm (ENNA) in order to assess whether and to what extent natural proteins are edited from random polypeptides employing 11 different structure-related variables (i.e. net charge, volume, surface area, coil, alpha helix, beta sheet, percentage of coil, percentage of alpha helix, percentage of beta sheet, percentage of secondary structure and surface hydrophobicity). The ENNA algorithm is capable to correctly distinguish natural proteins from random ones with an accuracy of 94.36%. Furthermore, we study the structural features of 32 random polypeptides misclassified as natural ones to unveil any structural similarity to natural proteins. Results show that random proteins misclassified by the ENNA algorithm exhibit a significant fold similarity to portions or subdomains of extant proteins at atomic resolution. Altogether, our results suggest that natural proteins are significantly edited from random polypeptides and evolutionary editing can be readily detected analyzing structural features. Furthermore, we also show that the ENNA, employing simple structural descriptors, can predict whether a protein chain is natural or random
Choices on contraceptive methods in post-abortion family planning clinic in the northeast Brazil
Increased insolation threshold for runaway greenhouse processes on Earth like planets
Because the solar luminosity increases over geological timescales, Earth
climate is expected to warm, increasing water evaporation which, in turn,
enhances the atmospheric greenhouse effect. Above a certain critical
insolation, this destabilizing greenhouse feedback can "runaway" until all the
oceans are evaporated. Through increases in stratospheric humidity, warming may
also cause oceans to escape to space before the runaway greenhouse occurs. The
critical insolation thresholds for these processes, however, remain uncertain
because they have so far been evaluated with unidimensional models that cannot
account for the dynamical and cloud feedback effects that are key stabilizing
features of Earth's climate. Here we use a 3D global climate model to show that
the threshold for the runaway greenhouse is about 375 W/m, significantly
higher than previously thought. Our model is specifically developed to quantify
the climate response of Earth-like planets to increased insolation in hot and
extremely moist atmospheres. In contrast with previous studies, we find that
clouds have a destabilizing feedback on the long term warming. However,
subsident, unsaturated regions created by the Hadley circulation have a
stabilizing effect that is strong enough to defer the runaway greenhouse limit
to higher insolation than inferred from 1D models. Furthermore, because of
wavelength-dependent radiative effects, the stratosphere remains cold and dry
enough to hamper atmospheric water escape, even at large fluxes. This has
strong implications for Venus early water history and extends the size of the
habitable zone around other stars.Comment: Published in Nature. Online publication date: December 12, 2013.
Accepted version before journal editing and with Supplementary Informatio
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