A Novel Strategy for Computing Routing Paths for Software-Defined Networks Based on MOCell Optimization

Software-defined networking (SDN) is the fastest growing and most widely deployed network infrastructure due to its adaptability to new networking technologies and intelligent applications. SDN simplifies network management and control by separating the control plane from the data plane. The SDN controller performs the routing process using the traditional shortest path approach to obtain end-to-end paths. This process usually does not consider the nodes’ capacity and may cause network congestion and delays, affecting flow performance. Therefore, we evaluate the most conventional routing criteria in the SDN scenario based on Dijkstra’s algorithm and compare the found paths with our proposal based on a cellular genetic algorithm for multi-objective optimization (MOCell). We compare our proposal with another multi-objective evolutionary algorithm based on decomposition (MOEA/D) for benchmark purposes. We evaluate various network parameters such as bandwidth, delay, and packet loss to find the optimal end-to-end path. We consider a large-scale inter-domain SDN scenario. The simulation results show that our proposed method can improve the performance of data streams with TCP traffic by up to 54% over the traditional routing method of the shortest path and by 33% for the highest bandwidth path. When transmitting a constant data stream using the UDP protocol, the throughput of the MOCell method is more than 1.65% and 9.77% for the respective paths

A Novel Strategy for Computing Routing Paths for Software-Defined Networks Based on MOCell Optimization

Software-defined networking (SDN) is the fastest growing and most widely deployed network infrastructure due to its adaptability to new networking technologies and intelligent applications. SDN simplifies network management and control by separating the control plane from the data plane. The SDN controller performs the routing process using the traditional shortest path approach to obtain end-to-end paths. This process usually does not consider the nodes’ capacity and may cause network congestion and delays, affecting flow performance. Therefore, we evaluate the most conventional routing criteria in the SDN scenario based on Dijkstra’s algorithm and compare the found paths with our proposal based on a cellular genetic algorithm for multi-objective optimization (MOCell). We compare our proposal with another multi-objective evolutionary algorithm based on decomposition (MOEA/D) for benchmark purposes. We evaluate various network parameters such as bandwidth, delay, and packet loss to find the optimal end-to-end path. We consider a large-scale inter-domain SDN scenario. The simulation results show that our proposed method can improve the performance of data streams with TCP traffic by up to 54% over the traditional routing method of the shortest path and by 33% for the highest bandwidth path. When transmitting a constant data stream using the UDP protocol, the throughput of the MOCell method is more than 1.65% and 9.77% for the respective paths

Application-Aware Flow Forwarding Service for SDN-Based Data Centers

Security and Quality of Service (QoS) in communication networks are critical factors supporting end-to-end dataflows in data centers. On the other hand, it is essential to provide mechanisms that enable different treatments for applications requiring sensitive data transfer. Both applications’ requirements can vary according to their particular needs. To achieve their goals, it is necessary to provide services so that each application can request both the quality of service and security services dynamically and on demand. This article presents QoSS, an API web service to provide both Quality of Service and Security for applications through software-defined networks. We developed a prototype to conduct a case study to provide QoS and security. QoSS finds the optimal end-to-end path according to four optimization rules: bandwidth-aware, delay-aware, security-aware, and application requirements (considering the bandwidth, delay, packet loss, jitter, and security level of network nodes). Simulation results showed that our proposal improved end-to-end application data transfer by an average of 45%. Besides, it supports the dynamic end-to-end path configuration according to the application requirements. QoSS also logs each application’s data transfer events to enable further analysis

Application of the omics sciences to the study of

In this review, we focus on the sequenced genomes of the pathogens Naegleria fowleri, Acanthamoeba spp. and Balamuthia mandrillaris, and the remarkable discoveries regarding the pathogenicity and genetic information of these organisms, using techniques related to the various omics branches like genomics, transcriptomics, and proteomics. Currently, novel data produced through comparative genomics analyses and both differential gene and protein expression in these free-living amoebas have allowed for breakthroughs to identify genes unique to N. fowleri, genes with active transcriptional activity, and their differential expression in conditions of modified virulence. Furthermore, orthologous genes of the various nuclear genomes within the Naegleria and Acanthamoeba genera have been clustered. The proteome of B. mandrillaris has been reconstructed through transcriptome data, and its mitochondrial genome structure has been thoroughly described with a unique characteristic that has come to light: a type I intron with the capacity of interrupting genes through its self-splicing ribozymes activity. With the integration of data derived from the diverse omic sciences, there is a potential approximation that reflects the molecular complexity required for the identification of virulence factors, as well as crucial information regarding the comprehension of the molecular mechanisms with which these interact. Altogether, these breakthroughs could contribute to radical advances in both the fields of therapy design and medical diagnosis in the foreseeable future

Distribution and Current State of Molecular Genetic Characterization in Pathogenic Free-Living Amoebae

Free-living amoebae (FLA) are protozoa widely distributed in the environment, found in a great diversity of terrestrial biomes. Some genera of FLA are linked to human infections. The genus Acanthamoeba is currently classified into 23 genotypes (T1-T23), and of these some (T1, T2, T4, T5, T10, T12, and T18) are known to be capable of causing granulomatous amoebic encephalitis (GAE) mainly in immunocompromised patients while other genotypes (T2, T3, T4, T5, T6, T10, T11, T12, and T15) cause Acanthamoeba keratitis mainly in otherwise healthy patients. Meanwhile, Naegleria fowleri is the causative agent of an acute infection called primary amoebic meningoencephalitis (PAM), while Balamuthia mandrillaris, like some Acanthamoeba genotypes, causes GAE, differing from the latter in the description of numerous cases in patients immunocompetent. Finally, other FLA related to the pathologies mentioned above have been reported; Sappinia sp. is responsible for one case of amoebic encephalitis; Vermamoeba vermiformis has been found in cases of ocular damage, and its extraordinary capacity as endocytobiont for microorganisms of public health importance such as Legionella pneumophila, Bacillus anthracis, and Pseudomonas aeruginosa, among others. This review addressed issues related to epidemiology, updating their geographic distribution and cases reported in recent years for pathogenic FLA

Dietary Use of Methionine Sources and <i>Bacillus amyloliquefaciens</i> CECT 5940 Influences Growth Performance, Hepatopancreatic Histology, Digestion, Immunity, and Digestive Microbiota of <i>Litopenaeus vannamei</i> Fed Reduced Fishmeal Diets

An 8-week feeding trial investigated the effect of Fishmeal (FM) replacement by soybean meal (SBM) and poultry by-product meal (PBM) in diets supplemented with DL-Met, MET-MET (AQUAVI®), Bacillus amyloliquefaciens CECT 5940 (ECOBIOL®) and their combinations on growth performance and health of juvenile Litopenaeus vannamei. A total of six experimental diets were formulated according to L. vannamei nutritional requirements. A total of 480 shrimp (0.30 ± 0.04 g) were randomly distributed into 24 tanks (4 repetitions/each diet, 20 shrimp/tank). Shrimp were fed with control diet (CD; 200 g/Kg fishmeal) and five diets with 50% FM replacement supplemented with different methionine sources, probiotic (B. amyloliquefaciens CECT 5940) and their combinations: D1 (0.13% DL-MET), D2 (0.06% MET-MET), D3 (0.19% MET-MET), D4 (0.13% DL-MET plus 0.10% B. amyloliquefaciens CECT 5940 and D5 (0.06% MET-MET plus 0.10% B. amyloliquefaciens CECT 5940). Shrimp fed D3 and D5 had significantly higher final, weekly weight gain, and final biomass compared to shrimp fed CD (p p p p Pseudoalteromonas and Demequina related to carbohydrate metabolism and immune stimulation. Also, shrimp fed D3 and D5 increased the abundance of beneficial eukaryotic microorganism as Aurantiochytrium and Aplanochytrium were related to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) production which plays a role in growth promoting or boosting the immunity of aquatic organisms. Therefore, fishmeal could be partially substituted up to 50% by SBM and PBM in diets supplemented with 0.19% MET-MET (AQUAVI®) or 0.06% MET-MET (AQUAVI®) plus 0.10% B. amyloliquefaciens CECT 5940 (ECOBIOL®) and improve the productive performance, health, and immunity of white shrimp. Further research is necessary to investigate synergistic effects of amino acids and probiotics in farmed shrimp diets, as well as to evaluate how SBM and PBM influence the fatty acid composition of reduced fishmeal diets and shrimp muscle quality. Nevertheless, this information could be interesting to develop low fishmeal feeds for aquaculture without affecting the growth and welfare of aquatic organisms

Effect of genotype and protein source on performance of Pacific white shrimp (Litopenaeus vannamei)

Shrimp farming is supported by fast-growth and high-resistance genotypes. Protein requirement is important for shrimp perfomance. Fishmeal is the main source, but their limited production increase feed formulation costs for aquaculture. This study evaluated the effect of genotype and protein source on performance of two shrimp genotypes. Shrimps with fast-growth (FG) and high-resistance (HR) were randomly assigned to two dietary treatments (animal and vegetal protein) in a 2 × 2 factorial design. A 36-day bioassay was realised in clear-water hyper-intensive system to compare FG and HR performance using three replicate tanks for each genotype and dietary treatment. Each tank was seeded with 10 shrimp with average initial weight of 2.03 ± 0.10 g for FG genotype and 2.07 ± 0.02 g for HR genotype, at a density of 250 shrimp/m3. A weekly biometry was realised to monitor the shrimp performance. We observed a significant interaction (p < .05) between genotype and diet for shrimp growth performance. Compared with HR shrimp, FG shrimp showed higher growth and better feed efficiency. The maximum weight gain was recorded, FG shrimp was significantly higher than HR shrimp independently of protein source. Diet with different protein source significantly influence the performance of FG shrimp, while in HR shrimp there is no significant difference between dietary treatment. The comparison showed that genotype, diet and their interactions influenced the performance of Litopenaeus vannamei. This research may be useful for improving genetic selection programmes, reducing feed costs for shrimp industry and design-feeding strategies for shrimp genotypes.Highlights Litopenaeus vannamei genotypes respond differently to diet. Fishmeal reduction on diet is posible in shrimps with high resistance. Genotype and diet interaction influence shrimp performance

Transcriptional response of immune-related genes in Litopenaeus vannamei cultured in recirculating aquaculture systems with elevated CO2

This short-term study evaluated the effect of non-lethal high CO2 concentration on the transcriptional response of immune-related genes of Pacific white shrimp (Litopenaeus vannamei) cultured in recirculating aquaculture systems (RAS). Two experimental groups were created: high CO2 (47.67±2.04 mg L−1) and low CO2 (2.0±1.93 mg L−1). Shrimp of 8.85±1.20 g were placed randomly at a density equivalent to 100 individuals m−3 and were monitored at 6, 12, 18, and 24 h. The transcriptional response of immune-related genes was analyzed by qPCR. Gene expression of hemocyanin, prophenoloxidase, and heat shock protein 60 was downregulated at 24 h, suggesting affectations on oxygen transportation, melanization, and protein functioning of L. vannamei under high CO2 concentrations. Also, gene up-regulation of lipopolysaccharide- and β-glucan-binding protein and cytosolic manganese superoxide dismutase can impair the bacterial recognition and antioxidant defense of shrimp exposed to high CO2 concentrations. These results suggest that concentration at about 47 mg L−1 of CO2 can significantly influence the transcriptional response modulation of immune-related gene

Adaptation of the Wound Healing Questionnaire universal-reporter outcome measure for use in global surgery trials (TALON-1 study): mixed-methods study and Rasch analysis

BackgroundThe Bluebelle Wound Healing Questionnaire (WHQ) is a universal-reporter outcome measure developed in the UK for remote detection of surgical-site infection after abdominal surgery. This study aimed to explore cross-cultural equivalence, acceptability, and content validity of the WHQ for use across low- and middle-income countries, and to make recommendations for its adaptation.MethodsThis was a mixed-methods study within a trial (SWAT) embedded in an international randomized trial, conducted according to best practice guidelines, and co-produced with community and patient partners (TALON-1). Structured interviews and focus groups were used to gather data regarding cross-cultural, cross-contextual equivalence of the individual items and scale, and conduct a translatability assessment. Translation was completed into five languages in accordance with Mapi recommendations. Next, data from a prospective cohort (SWAT) were interpreted using Rasch analysis to explore scaling and measurement properties of the WHQ. Finally, qualitative and quantitative data were triangulated using a modified, exploratory, instrumental design model.ResultsIn the qualitative phase, 10 structured interviews and six focus groups took place with a total of 47 investigators across six countries. Themes related to comprehension, response mapping, retrieval, and judgement were identified with rich cross-cultural insights. In the quantitative phase, an exploratory Rasch model was fitted to data from 537 patients (369 excluding extremes). Owing to the number of extreme (floor) values, the overall level of power was low. The single WHQ scale satisfied tests of unidimensionality, indicating validity of the ordinal total WHQ score. There was significant overall model misfit of five items (5, 9, 14, 15, 16) and local dependency in 11 item pairs. The person separation index was estimated as 0.48 suggesting weak discrimination between classes, whereas Cronbach's α was high at 0.86. Triangulation of qualitative data with the Rasch analysis supported recommendations for cross-cultural adaptation of the WHQ items 1 (redness), 3 (clear fluid), 7 (deep wound opening), 10 (pain), 11 (fever), 15 (antibiotics), 16 (debridement), 18 (drainage), and 19 (reoperation). Changes to three item response categories (1, not at all; 2, a little; 3, a lot) were adopted for symptom items 1 to 10, and two categories (0, no; 1, yes) for item 11 (fever).ConclusionThis study made recommendations for cross-cultural adaptation of the WHQ for use in global surgical research and practice, using co-produced mixed-methods data from three continents. Translations are now available for implementation into remote wound assessment pathways