In brain image processing applications the skull stripping is an essential part to explore. In numerous medical image applications the skull stripping stage act as a pre-processing step as due to this stage the accuracy of diagnosis increases in the manifold. The MR image skull stripping stage removes the non-brain tissues from the brain part such as dura, skull, and scalp. Nowadays MRI is an emerging method for brain imaging. However, the existence of the skull region in the MR brain image and the low contrast are the two main drawbacks of magnetic resonance imaging. Therefore, we have proposed a method for contrast enhancement of brain MRI using histogram equalization techniques. While morphological image processing technique is used for skull stripping from MR brain image. We have implemented our proposed methodology in MATLAB R2015a platform. Mean square error (MSE) and peak signal to noise ratio (PSNR) has been used to evaluate the results of our presented method. The experimental results illustrate that our proposed method effectively enhance the image and remove the skull from brain MRI.

Rationale, aims, and objectives: Fluid management plays a pivotal role for heart failure (HF) patients. Medical fluid intake and output recording scheme by health care professional is complicated, which is not easily conducive to carry out by HF patients for self-management at home. This study aimed to optimize the professional fluid records for the self-management of HF patients and evaluate the efficacy of this simplified recording scheme of fluid intake and output. Methods: A randomized, non-blinded and controlled trial with allocation concealment was conducted. A total of 140 HF patients were enrolled and randomly divided into professional recording group (PRG, n=70) and simplified recording group (SRG, n=70). Ultimately, 129 HF patients (PRG, n=65, and SRG, n=64) completed these experiments. Basic clinical characteristics, days of clinical stability, clinical congestion score (CCS), Minnesota Living with Heart Failure Questionnaire (MLHFQ) and frequency of electrolyte disturbances in these patients were collected. Results: Compared to PRG patients, SRG patients also improved their HF symptoms (including shortness of breath and fluid retention), and did not show the prolonged hospitalization time after similar intravenous diuretic treatment. Additionally, the parameters of clinical stability, CCS, MLHFQ, electrolyte disturbances and body weight in SRG patients were not inferior to that of PRG patients (P >0.05). Conclusions: This simplified fluid intake and output recording scheme was safe, efficient and non-inferior to the professional mode, which might effectively enhance their feasibility of self-management, and improve their quality of life in HF patients.

Study of species’ ecological niches through evolutionary history can elucidate speciation mechanisms, yet current comparative phylogenetic methods consistently overestimate niche evolution. Here we propose a method by which to characterize species’ fundamental ecological niches for comparative phylogenetic analysis using a bin-based approach that incorporates uncertainty in niche estimates. Simulation analysis using a traditional characterization method (median value calculated from species’ known occurrences) estimated a significantly higher rate of niche evolution than using our proposed method, and differences in rate estimates were consistent regardless of the number of simulated taxa in a phylogeny. We also demonstrate how to perform ancestral state reconstructions under the new coding system; reconstructions are performed for each bin individually, and ancestral fundamental niches inferred by smoothing each node’s reconstructions across all bins. Finally, we provide a worked empirical example of our method, investigating ecological niche evolution in 34 species of New World orioles (Icterus spp.). Ecological niches were generally conserved in the group, and only a few lineages appear to have experienced niche reduction and specialization.

In this study, we used two common ant species (Lasius niger and L. neoniger) to assay how they translate variation in the diet (both in composition and frequency) into growth. We measured colony development for over 8 months and measured several phenotypic traits of the worker caste, and examined whether forager preference corresponded with diet quality. Individuals (workers) and colonies (superorganisms) increased in size with increasing amounts of protein in the diet, and as a function of how much food was available. Optimal colony growth was a balance between survival and growth, and each of these were maximized with different nutrient regimes. Interestingly, forager preference was not totally aligned with the diet that maximized colony growth. Our results highlight that: 1) organism and superorganism size are controlled by the same nutrients, and this may reflect a common molecular basis for size across life’s organizational levels, 2) there are nutrient trade-offs that are associated with life-history trade-offs, likely leading to selection for a balanced diet, and 3) the connection between the preference of foragers for different nutrients and how nutrient combinations affect colony success and demographics are complex and only beginning to be understood.

Understanding spatiotemporal population trends and their drivers is a key aim in population ecology. We further need to be able to predict how the dynamics and sizes of populations are affected in the long term by changing landscapes and climate. However, predictions of future population trends are sensitive to a range of modelling assumptions. Deadwood-dependent fungi are an excellent system for testing the performance of different predictive models of sessile species as these species have different rarity and spatial population dynamics, the populations are structured at different spatial scales and they utilize distinct substrates. We tested how the projected large scale occupancies of species with differing landscape-scale occupancies are affected over the coming century by different modelling assumptions. We compared projections based on occupancy models against colonization-extinction models, conducting the modelling at alternative spatial scales, and using fine or coarse resolution deadwood data. We also tested effects of key explanatory variables on species occurrence and colonization-extinction dynamics. The hierarchical Bayesian models applied were fitted to an extensive repeated survey of deadwood and fungi at 174 patches. We projected higher occurrence probabilities and more positive trends using the occupancy models compared to the colonisation-extinction models, with greater difference for the species with lower occupancy, colonization rate and colonization:extinction ratio than for the species with higher estimates of these statistics. The magnitude of future increase in occupancy depended strongly on the spatial modelling scale and resource resolution. We encourage using colonisation-extinction models over occupancy models, modelling the process at the finest resource-unit resolution that is utilizable by the species, and conducting projections for the same spatial scale and resource resolution at which the model fitting is conducted. Further, the models applied should include key variables driving the metapopulation dynamics, such as the availability of suitable resource units, habitat quality and spatial connectivity.

Scale and tempo of brain expansion in the course of human evolution implies that this process was driven by a positive feedback. The ‘cultural drive’ hypothesis suggests a possible mechanism for the runaway brain-culture coevolution wherein high-fidelity social learning results in accumulation of cultural traditions which, in turn, promote selection for still more efficient social learning. Here we explore this evolutionary mechanism by means of computer modeling. Simulations confirm its plausibility in a social species in a socio-ecological situation that makes the sporadic invention of new beneficial and cognitively demanding behaviours possible. The chances for the runaway brain-culture coevolution increase when some of the culturally transmitted behaviours are individually beneficial while the others are group-beneficial. In this case, ‘cultural drive’ is possible under varying levels of between-group competition and migration. Modeling implies that brain expansion can receive additional boost if the evolving mechanisms of social learning are costly in terms of brain expansion (e.g., rely on complex neuronal curcuits) and tolerant to the complexity of information transferred, that is, make it possible to transfer complex skills and concepts easily. Human language presumably fits this description. Modeling also confirms that the runaway brain-culture coevolution can be accelerated by additional positive feedback loops via population growth and lifespan extension, and that between-group competition and cultural group selection can facilitate the propagation of group-beneficial behaviours and remove maladaptive cultural traditions from the population’s culture, which individual selection is unable to do.

In this paper Spontaneous Process Algorithm (SPA) is proposed to solve optimal reactive power problem. Formulation of the projected algorithm is done by imitating the process done during nuclear fission and fusion. Every item of a nucleus attribute symbolizes each solution variable. Sequence of operators directs the nucleus and in order to avoid the local optimum it will imitate the dissimilar condition of reaction. In the exploration space nucleus symbolizes the variables and potential solution. Levy flight has been intermingled in the procedure to enhance the diversification and intensification in the search. Spontaneous Process Algorithm (SPA) has been tested in standard IEEE 14, 30, 57,118,300 bus test systems and simulation results show the projected algorithm reduced the real power loss comprehensively and there is increase in percentage of reduction of real power loss.

The assembly of the world’s most biodiverse region, the Neotropics, was traditionally considered the result of long-term environmental stability. Studies gathered during the last decades suggest that environmental “instability” instead, specially the dramatic modifications caused by the uplift of the Andes, was responsible of the Neotropical diversity. Yet a comprehensive understanding has been hindered by a lack of large-scale comparative data across wide phylogenetic and ecological contexts. Here, we evaluate the timing and drivers of Neotropical diversification in a large sample of Neotropical clades: 150 phylogenies (12,524 species) of seed plants and major tetrapods (amphibians, mammals, squamates, and birds). We unveil five trends: (1) biodiversity levels before the Quaternary were comparable (or higher) to those of the present,; (2) half of the clades diversified at constant rates; (3) past environmental variations correlate with diversification changes in 37% of the lineages, but with contrasting responses: (4) birds and mammals diversified extensively during warm periods and global cooling resulted in synchronized slowdowns of diversification; plant diversification generally increased during cooling; and (5) the rise of the Andes mostly impacted amphibians and squamates. Our study suggests that environmental instability over macroevolutionary scales may in fact act as a driving force of Neotropical diversification.

Intermittent rivers are prevalent in many countries across Europe and in Mediterranean countries outside Europe, but little is known about the temporal evolution of intermittency characteristics and their relationships with climate variability. In this study, a trend analysis is performed on the annual and seasonal number of zero-flow days, the maximum duration of dry spells and the mean date of the zero-flow events, on a database of 452 rivers in European and in Mediterranean countries outside Europe, with varying degrees of intermittence. In addition, the relationships between flow intermittence and climate are investigated using the Standardized Precipitation Evapotranspiration Index (SPEI) and six climate indices describing large scale atmospheric circulation. Results indicated a strong spatial variability of the seasonal patterns of intermittence and the annual and seasonal number of zero-flow days, which highlights the controls exerted by local catchment properties. Most of the detected trends indicate an increasing number of zero-flow days which also tend to occur earlier in the year, in particular in Southern Europe. The SPEI is found to be strongly related to the annual and seasonal zero-flow day occurrence in more than half of the stations for different accumulation times between 12 and 24 months. Conversely, there is a weak dependence of river intermittence with large-scale circulation indices. Overall, these results suggest increased water stress in intermittent rivers that may affect their biota and biochemistry and also reduce available water resources.

Introduction. Vascular stress at the level of the uterus-placental unit, with chronic placental ischemia, results in intrauterine growth restriction. Expectation management can be used, when the situation allows, in cases of compensated intrauterine growth restriction. Aim: The aim of our study was to evaluate the neonatal prognosis of preterm births with and without growth restriction and term births with growth restriction in order to improve decisional accuracy regarding the termination of pregnancy. Results: The frequency of term birth infants with low birth weight for gestational age was approximately 2%. The male gender, predominated only in the group of premature infants with normal weight for the gestational age. The highest frequency of neonatal complications studied occurred in the group of preterm neonates SGA (small for gestational age) with statistical significance obtained for cardio-vascular arrest acute respiratory failure, ulcer-necrotic enterocolitis, respiratory distress, cerebral edema, intraventricular hemorrhage, cerebral hemorrhage, pulmonary hemorrhage, neonatal infection, hypoglycemia, retinopathy, anemia, hemorrhagic disease, disseminated intravascular coagulation, disease of hyaline membranes, neonatal sepsis, need for intensive neonatal therapy and death. Conclusion: Immediate neonatal adaptation of SGA preterm neonates is more deficient than for preterm neonates with appropriate weight for gestational age; the adaptation of preterm neonates, in turn, is more deficient than term newborns with intrauterine growth restriction. The term newborns with intrauterine growth restriction have a neonatal adaptation comparable to that of the term newborns with weight corresponding to the gestational age.

Acrylic fibers are synthetic fibers made from a polymer (polyacrylonitrile) with an average molecular weight of ~100,000, about 1900 monomer units. For a fiber to be called “acrylic” in the US, the polymer must contain at least 85% acrylonitrile monomer. Typical comonomers are vinyl acetate or methyl acrylate. DuPont created the first acrylic fibers in 1941 and trademarked them under the name Orlon.[1] It was first developed in the mid-1940s but was not produced in large quantities until the 1950s. Strong and warm, acrylic fiber is often used for sweaters and tracksuits and as linings for boots and gloves, as well asin furnishing fabrics and carpets. It is manufactured as a filament, then cut into short staplelengths similar to wool hairs, and spun into yarn. Modacrylic is a modified acrylic fiber that contains at least 35% and at most 85%acrylonitrile monomer. The comonomers vinyl chloride, vinylidene chloride or vinyl bromide used in modacrylic give the fiber flame retardant properties. End-uses of modacrylic include faux fur, wigs, hair extensions and protective clothing.

In this paper, experimental results are reported to quantify the effect of hydrophobic coating LT-8 on frictional drag of water flow in pipes of 450 mm length. Five pipes of 1, 2, 3, 4 and 5 mm inner diameter were tested. The results from 1, 2 and 3 mm diameter pipes demonstrated an average frictional drag reduction of 9%, 11.5% and 3%, respectively, while the results from 4mm and 5mm pipes showed an increase in frictional drag of 12% and 10%, respectively. The 2mm and 4mm pipes were also tested with a half application of hydrophobic coating. The half coated 2mm pipe showed decrease in drag while 4mm pipe showed increase in drag. The results indicate a relationship between drag reduction/ increase withnthe percentage of coated surface. The main conclusions are, the flow changed from laminar state to the liquid-air wetting surface condition (Cassie-Baxter wetting state) at the pipe surface and then destabilized by the turbulent boundary layer and entered the liquid wetting surface (Wenzel wetting state) will be appeared. This transition lead to a reduction in friction drag for laminar flow condition and increase in drag for turbulent flow condition.

The mechanisms of Cp*Rh(OAc)2-catalyzed coupling reaction of N-methoxybenzamide with alkyl-terminated enyne have been investigated by density functional theory (DFT) calculations. With the addition of NaOAc and changing solvent, the product transforms from lactam P1 in reaction A to iminolactone P2 in reaction B, due to the formed stable OAc- coordinated intermediate. The electronic effect and steric effect account for the observed regioselectivity in reaction B collectively.

We develop a novel approach to trophic metacommunities and use it to study the effect of habitat loss on food webs. Our method assigns a spatially realistic Levins-type metapopulation model to each species, then couples them by making species extinction rates depend on the likelihood of the presence of species’ prey items via a Bayesian network representation of the food web. The method yields general insights into metacommunity ecology, revealing that metacommunity processes alone can restrict the maximum number of trophic levels to a handful at most over fragmented landscapes, independent of energetic or other constraints. It also allows one to repurpose known results of classical metapopulation theory for metacommunities, such as ranking the habitat patches of the landscape with respect to their importance to the persistence of the metacommunity as a whole. Using these tools, we explore how progressive habitat loss affects species extinction rates. The outcome depends on the order of habitat removal: focusing on removing patches which are least crucial to persistence first (best-case scenario) means the metacommunities can often tolerate the removal of more than 90% of their patches. Whereas removing the most crucial patches first (worst-case scenario) leads to the collapse of metacommunities very quickly. Surprisingly, removing patches at random is nearly indistinguishable in its effects from the worst-case scenario. In all cases, species’ vulnerability to habitat loss is greater at higher trophic levels, stressing the risk of network downsizing for food webs under progressive habitat loss.

The transformation mechanism and kinetics of 2-chloro-1,1,2-trifluoroethyl-difluoromethyl-ether (CTDE, CHF2OCF2CHFCl) triggered by OH radicals were researched by DFT methods and canonical variational transition state theory. The computational rate constant including small-curvature tunneling correction was in commendable agreement with the experimental data. Two hydrogen abstraction channels to form the alkyl radicals of C·F2OCF2CHFCl and CHF2OCF2C·FCl were observed, and the formation of CHF2OCF2C·FCl was more favorable than C·F2OCF2CHFCl in kinetics and thermodynamics. Subsequent evolution of CHF2OCF2C·FCl in the presence of NO and O2 indicated that the organic nitrate (CHF2OCF2CONO2FCl) was the stable product. The dechlorinate of alkoxy radical (CHF2OCF2C(O·)FCl) was the most favorable degradation channel and the estimated ozone depletion potential for CTDE relative to CFC-11 was 0.0204, which could lead to a consequence of ozone depletion. Computed atmospheric lifetime for CTDE was 3.69 years by considering the combined contributions from OH radicals and Cl atoms. The total radiative forcing and global warming potential of CTDE were respectively 0.547 W m-2 ppbv and 628.58 (100 years) at 298 K, suggesting that the contribution of CTDE to the greenhouse effect is moderate.

The ground state energy of hydrogen and helium atom confined by a hard prolate spheroidal cavity is calculated in the presence of plasma environment. The effect of compression as well as the presence of plasma environment on the energy of hydrogen and helium in ground state is studied in details. The plasma effect is taken care of by employing effective screening of the Coulomb potential. The Schrodinger equation is solved using the variational Monte Carlo method with an accurate trial wave function depending on many variational parameters. The results were extended also to include He-like isoelectronic ions up to Z = 10. Our results are compared with the most recent accurate values. The obtained results are in good agreement with the most recent results.

Methanol dehydration at vapor phase atmospheric pressure in fixed bed (2.54 cm inside diameter X 110 cm meter high) catalytic reactor was studied in this investigation. Three catalysts were used (Alumina, Ziolite 5A and resin) and moderate range of temperature (90-120 0C). Weight ratio of catalyst to molar flow rate (W/FA) from 27 to 81 (gcat.hr/gmol) was selected. Both Alumina and ziolite showed weak activity at this range of temperature while resin was better. Conversion of methanol to DME showed significant dependence on increasing temperature and flow rate (highest conversion was 8% at 120 0C and W/F=81 gcat. hr/gmol). Deactivation of resin with time was studied at optimum conditions, results showed no effect of time on both conversion and selectivity to produce DME. DME production selectivity was 100% at all operation circumstances. The nature of active sites of resin was studied by using selectivity poison procedure. Accordingly, acidic sites were mainly concerned with the reaction whereas Bronsted acidity has mainly contributed to the acidic sites.

A CALculation of PHase Diagrams (CALPHAD) approach was used to study the formation temperatures of nitride and carbonitride precipitates in nominated linepipe steels. The calculated results were in good agreement with relevant experimental data reported in the literatures, where the optimum titanium to nitrogen ratio and austenite grain growth was studied in similar steel compositions. The niobium concentration up to 0.12 wt% showed no influence on the formation temperature of nitrides in a common linepipe steel composition, while significantly increased the precipitation temperature of niobium carbides up to 0.03 wt%. Nitride precipitates contained a high concentration of titanium while niobium contributed mostly to the formation of carbide/carbonitrides. Although the dissolution and growth of precipitates are controlled kinetically, the thermodynamic calculation approach can be used to efficiently predict the equilibrium amount and composition of the stable phases in chemically complex systems. This results in a more accurate design of experiments, to minimise the number of tests required to obtain optimum chemical compositions and heat treatment procedures.

The process of intelligent interaction through brain machine interface requires quick and accurate extraction of Electroencephalogram (EEG) signals. However, the accuracy of signal classification varies with the signal extraction location. Is there a universal rule to follow to determine the optimal extraction location? This paper investigates the possibility of a universal rule to determine optimal extraction location through Welch, Support Vector Machine and Euclidean distance algorithms. The motor imagery EEG signals of 40 subjects were extracted and the classification correct rates of brain electrode signals in different positions were analyzed using Welch and Support Vector Machine algorithms. Then the electrodes were sorted according to the correct rate, and finally three pairs of electrodes with the highest correct rate were obtained. For comparison, this paper proposed another method of searching for the optimal electrodes, namely the combination of Welch and Euclidean distance algorithms. Ultimately, a similar conclusion was drawn from the above two methods: T3/T4, F3/F4 and C3/C4 electrodes usually have high classification accuracy. This result is helpful for quick customization of optimal brain electrode placement.

DNA has stored ‘data’ for millions of years, in the form of the 4 bases; A, T, G, and C. Synthetic attempts to recreate this huge data storing capability have promised the same levels of storage density and stability, but are yet to compete with current optical/magnetic storage devices due to the high error rates and large costs. A novel approach has been found, storing the data in the backbone of native DNA instead of the bases themselves, this greatly reduces costs, while reducing the error rate to 0. This new technique is also capable of bitwise random-access memory, opening the door to the world of molecular computing.In nature, DNA is found as a double-helix ladder compromising of billions of molecular building blocks known as bases (A, T, G, and C), coding instructions for proteins. The closely-packed nature of these nucleotides enable DNA to code for huge quantities of data; one gram of DNA is capable of holding 455 exabytes of data1 ( 1 exabyte = 1018 bytes), enough storage for all of the data produced by every major tech company…with room to spare. Traditional data storage methods are reaching their physical limits, with hard-drives being restricted to 1 terabyte (1012bytes) per square inch2. With the exponential growth of big data, alternative data storage methods such as DNA are starting to be explored, made possible due to the huge advances in DNA sequencing technology.Current approaches of DNA synthesis-based storage2–4assign segments of binary code to specific nucleotide sequences, these are then synthesised in vitro using enzymes to bind the nucleotides together, iterating through many cycles to form the string of DNA. The information encoded in the DNA can then be retrieved via next generation sequencing (NGS) or third generation nanopore sequencing. Nanopore sequencing entails feeding the string of DNA through a tiny hole, much like a thread going through a needle, reading each nucleotide as it passes through. Advancements in sequencing technologies allow for large sequences to be read at a relatively low cost; the total cost of the first human genome was ≈ £2.07 billion2, whereas sequencing a full genome now costs around £10002.However, despite the promise of synthesis-based DNA storage, issues arise during the synthesis step. The first issue is that adding one nucleotide per cycle takes hours to complete a full sequence, making it very slow and expensive compared to traditional optical and magnetic writing techniques. Secondly, DNA synthesis is naturally a very error prone process, with 1% of bases containing substitution (incorrect base attached) or indel (insertion or deletion of a base) errors3. This is a big issue when dealing with large volumes of DNA as errors are inevitable, this can have dire repercussions when dealing with compressed file formats. Finally, DNA synthesis machinery is limited to creating relatively short sequences, reducing the amount of readouts/ data, per fragment5.Tabatabaei et al. 5 propose a novel method to storing data using DNA, via a topological ‘nicking’ approach instead of direct synthesis. Therefore, the data is not stored in the nucleotides themselves, but the sugar-phosphate backbone of the DNA. This enables you to use a known sequence of DNA which you can map to a reference genome, bypassing the aforementioned issues associated with synthesis-based storage.

In this paper, the Dirichlet and Neumann boundary value problems for the steady-state Stokes system of partial differential equations for a compressible viscous fluid with variable viscosity coefficient is considered in two-dimensional bounded domain. Using an appropriate parametrix, this problem is reduced to a system of direct segregated boundary-domain integral equations (BDIEs). The BDIEs in the two-dimensional case have special properties in comparison with the three dimension because of the logarithmic term in the parametrix for the associated partial differential equations. Consequently, we need to set conditions on the function spaces or on the domain to ensure the invertibility of corresponding parametrix-based hydrodaynamic single layer and hypersingular potentials and hence the unique solvability of BDIEs. Equivalence of the BDIE systems to the Dirichlet and Neumann BVPs and the invertibility of the corresponding boundary-domain integral operators in appropriate Sobolev spaces are shown.

This research paper discusses the analytical and semi-analytical solutions of the quadratic–cubic fractional nonlinear Schrodinger (NLS) equation. By applying a new fractional operator we transform the fractional formula of the model to integer-order, which allows applying the analytical and numerical methods on it. The analytical solutions are obtained by the implementation of two distinct systematic schemes and the reported solutions are used in applying the Adomian decomposition method to get the semi-analytical wave solutions of this model. These solutions are used to characterize the changes over time of a physical system in which case of quantum influence, such as wave-particle duality. The comparison between the analytical and semi-analytical solutions are given to explain the accuracy of the obtained solutions.

In this paper, we deal with the wave equation with acoustic boundary conditions. The exponential stabilization is obtained by Lyapunov approach and Riemannian geometry method. We then apply our main theorem to the wave equations with memory type acoustic boundary conditions, which is not available in the literature and give an example in the end.

We consider various approximation properties for systems driven by a Mc Kean-Vlasov stochastic differential equations (MVSDEs) with continuous coefficients, for which pathwise uniqueness holds. We prove that the solution of such equations is stable with respect to small perturbation of initial conditions, parameters and driving processes. Moreover, the unique strong solutions may be constructed by an effective approximation procedure. Finally we show that the set of bounded uniformly continuous coefficients for which the corresponding MVSDE have a unique strong solution is a set of second category in the sense of Baire.