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Modern fighter aircraft increasingly need to conjugate aerodynamic performance and low observability. In this paper, we showcase a methodology for a gradient-based bidisciplinary aero-stealth optimization. The shape of the aircraft is parameterized with the help of a CAD modeler, and we optimize it with the SLSQP algorithm. The drag, computed with the help of a RANS method, is used as the aerodynamic criterion. For the stealth criterion, a function is derived from the radar cross-section in a given cone of directions and weighed with a function whose goal is to cancel the electromagnetic intensity in a given direction. Stealth is achieved passively by scattering back the electromagnetic energy away from the radar antenna, and no energy is absorbed by the aircraft, which is considered as a perfect conductor. A Pareto front is identified by varying the weights of the aerodynamic and stealth criteria. The Pareto front allows for an easy identification of the CAD model corresponding to a chosen aero-stealth trade-off.

This article presents single- and multi-disciplinary shape optimizations of a generic business jet wing at two transonic cruise flow conditions. The studies performed are based on two high-fidelity gradient-based optimization tools, assisted by the adjoint method (following both discrete and continuous approaches). Single discipline and coupled multi-disciplinary sensitivity derivatives computed from the two tools are compared and verified against finite differences. The importance of not making the frozen turbulence assumption in adjoint-based optimization is demonstrated. Then, a number of optimization runs, ranging from a pure aerodynamic with a rigid structure to an aerostructural one exploring the trade-offs between the involved disciplines, are presented and discussed. The middle-ground scenario of optimizing the wing with aerodynamic criteria and, then, performing an aerostructural trimming is also investigated.

Abstract Sexual selection is the process by which traits providing a mating advantage are favoured. Theoretical treatments of the evolution of sex by sexual selection propose that it operates by reducing the load of deleterious mutations. Here, we postulate instead that sexual selection primarily acts through females preferentially mating with males carrying beneficial mutations. We used simulation and analytical modelling to investigate the evolutionary dynamics of beneficial mutations in the presence of sexual selection. We found that female choice for males with beneficial mutations had a much greater impact on genetic quality than choice for males with low mutational load. We also relaxed the typical assumption of a fixed mutation rate. For deleterious mutations, mutation rate should always be minimized, but when rare beneficial mutations can occur, female choice for males with those rare beneficial mutations could overcome a decline in average fitness and allow an increase in mutation rate. We propose that sexual selection for beneficial mutations could overcome the ‘two-fold cost of sex’ much more readily than choice for males with low mutational load and may therefore be a more powerful explanation for the prevalence of sexual reproduction than the existing theory. If sexual selection results in higher fitness at higher mutation rates, and if the variability produced by mutation itself promotes sexual selection, then a feedback loop between these two factors could have had a decisive role in driving adaptation.

Abstract Outdoor biting by anopheline mosquitoes is one of the contributors to residual malaria transmission, but the profile of vectors driving this phenomenon is not well understood. Here, we studied the bionomics and genetically characterized populations of An. gambiae and An. funestus complexes trapped outdoors in three selected dryland areas including Kerio Valley, Nguruman and Rabai in Kenya. We observed a higher abundance of Anopheles funestus group members (n = 639, 90.6%) compared to those of the An. gambiae complex (n = 66, 9.4%) with An. longipalpis C as the dominant vector species with a Plasmodium falciparum sporozoite rate (Pfsp) of 5.2% (19/362). The known malaria vectors including An. funestus s.s. (8.7%, 2/23), An. gambiae (14.3%, 2/14), An. rivulorum (14.1%, 9/64), An. arabiensis (1.9%, 1/52) occurred in low densities and displayed high Pfsp rates, which varied with the site. Additionally, six cryptic species found associated with the An. funestus group harbored Pf sporozoites (cumulative Pfsp rate = 7.2%, 13/181). We detected low frequency of resistant 119F-GSTe2 alleles in An. funestus s.s. (15.6%) and An. longipalpis C (3.1%) in Kerio Valley only. Evidence of outdoor activity, emergence of novel and divergent vectors and detection of mutations conferring metabolic resistance to pyrethroid/DDT could contribute to residual malaria transmission posing a threat to effective malaria control.

This work aims at reinforcing simultaneously the coefficient of performance (COP) and the exergetic coefficient of performance (ECOP), in order to improve the operation of an absorption chiller to be used in tropical areas. It uses a new method based on the determination of variable one-line matrix that allows to find the NH3 mass fraction of NH3-NaSCN solution on each branch of the system.This matrix is obtained by substitution between the empirical formulae of NH3 and NH3-NaSCN from two different approaches, with the aim of making the current model more simple and less complex than those commonly used by other researchers. The approach developed is a direct digital method, easy to implement and allowing to find and understand some hidden functions of the black boxes of several energy simulation softwares, such as the Engineering Solver Equation (EES). The modeling of the system is carried out in Matlab to predict the temperatures and mass flows that can upgrade the system. The purpose is to contribute to the improvement and commissioning of an absorption chiller operating at thermal comfort temperatures in two cities in Cameroon: Douala and Yaoundé. The results show that the temperatures in the generator, condenser and absorber for which the COP and ECOP are maximum are respectively [92°C; 100°C]; 35°C, and [35°C; 40.8°C], and those of the mass flow rates of the refrigerant leaving the generator and condenser are respectively [0.44 kg/s; 0.86 kg/s] and 0.98 kg/s. The evaporator does not show these remarks. The simulation results can be used for thermodynamic optimisation of the cooling capacity (CC) and reduction of electrical energy consumption of the current system.

Insect-specific flaviviruses (ISFs), although not known to be pathogenic to humans and animals, can modulate the transmission of arboviruses by mosquitoes. In this study, we screened 6665 host-seeking, gravid and blood-fed mosquitoes for infection with flaviviruses and assessed the vertebrate hosts of the blood-fed mosquitoes sampled in Baringo and Kajiado counties; both dryland ecosystem counties in the Kenyan Rift Valley. Sequence fragments of two ISFs were detected. Cuacua virus (CuCuV) was found in three blood-fed Mansonia (Ma.) africana. The genome was sequenced by next-generation sequencing (NGS), confirming 95.8% nucleotide sequence identity to CuCuV detected in Mansonia sp. in Mozambique. Sequence fragments of a potential novel ISF showing nucleotide identity of 72% to Aedes flavivirus virus were detected in individual blood-fed Aedes aegypti, Anopheles gambiae s.l., Ma. africana and Culex (Cx.) univittatus, all having fed on human blood. Blood-meal analysis revealed that the collected mosquitoes fed on diverse hosts, primarily humans and livestock, with a minor representation of wild mammals, amphibians and birds. The potential impact of the detected ISFs on arbovirus transmission requires further research.

Hantaviruses are zoonotic rodent-borne viruses that are known to infect humans and cause various symptoms of disease, including hemorrhagic fever with renal and cardiopulmonary syndromes. They have a segmented single-stranded, enveloped, negative-sense RNA genome and are widely distributed. This study aimed to investigate the circulation of rodent-borne hantaviruses in peridomestic rodents and shrews in two semi-arid ecologies within the Kenyan Rift Valley. The small mammals were trapped using baited folding Sherman traps set within and around houses, then they were sedated and euthanatized through cervical dislocation before collecting blood and tissue samples (liver, kidney, spleen, and lungs). Tissue samples were screened with pan-hantavirus PCR primers, targeting the large genome segment (L) encoding the RNA-dependent RNA polymerase (RdRp). Eleven of the small mammals captured were shrews (11/489, 2.5%) and 478 (97.5%) were rodents. A cytochrome b gene-based genetic assay for shrew identification confirmed the eleven shrews sampled to be Crocidura somalica. Hantavirus RNA was detected in three (3/11, 27%) shrews from Baringo County. The sequences showed 93–97% nucleotide and 96–99% amino acid identities among each other, as well as 74–76% nucleotide and 79–83% amino acid identities to other shrew-borne hantaviruses, such as Tanganya virus (TNGV). The detected viruses formed a monophyletic clade with shrew-borne hantaviruses from other parts of Africa. To our knowledge, this constitutes the first report published on the circulation of hantaviruses in shrews in Kenya.

Contents A three-year-old intact female Old English sheepdog was presented for evaluation of infertility. A uterine biopsy was performed during dioestrus, and the microscopic appearance was inconsistent with progesterone stimulation; the glands were sparse, simple and failed to show coiling, while the glandular epithelium was cuboidal instead of columnar. There was very little evidence of glandular activity. Due to the inappropriate appearance of the glands for the stage of the cycle, immunohistochemistry for progesterone receptors was performed. No progesterone receptor-positive immunoreactivity was identified in the endometrial luminal epithelium, glandular epithelium or stroma. Weak intranuclear immunoreactivity was identified within the smooth muscle cells of the myometrium. The absence of progesterone receptors within the endometrial glands is the most likely explanation for the abnormal appearance of the endometrium and for this bitch's infertility. To our knowledge, this is the first report of endometrial progesterone receptor absence in a bitch. [ABSTRACT FROM AUTHOR]

Se optimizaron las condiciones de extracción mecánica de hidrocoloides de hojas de Malva sylvestris y determinó el comportamiento reológico y actividad antioxidante. Las hojas fueron hidratadas en 15, 20 y 25 g de agua/g de hojas polvo, por 30, 60 y 90 min, luego solubilizadas por expresión mediante paletas a presión de 53 db y 424, 508 y 592 mov/min por 60, 120 y 180 s. La reología en soluciones al 0,7, 1,4 y 2,1% (p/v) a 20, 30 y 40 °C se efectuó con reómetro y la actividad antioxidante a 20, 40, 60 y 80 °C se realizó cuantificando polifenoles totales y captación de radicales libres con los métodos de Folin-Ciocalteu y DPPH respectivamente. Del estudio se concluye, que para obtener rendimiento máximo en la extracción de 19,21% (p/p), las condiciones óptimas se ajustaron a modelo de segundo orden con hidratación de 25 g de agua/g de hojas polvo por 30 min y solubilización a 592 mov/min por 180s. Los reogramas obedecieron al modelo de Ostwald, mostrando los hidrocoloides ser fluidos pseudoplásticos. Los polifenoles totales (mg AGE / 100 g muestra) de 20 a 80 °C, disminuyó de 131,17 a 78,87 y la captación de radicales libres DPPH (mM Trolox / g muestra) de 60 a 80 °C decreció de 0,422 a 0,298.

Aedes simpsoni complex has a wide distribution in Africa and comprises at least three described sub-species including the yellow fever virus (YFV) vector Ae. bromeliae. To date, the distribution and relative contributions of the sub-species and/or subpopulations including bionomic characteristics in relation to YF transmission dynamics remain poorly studied. In this study conducted in two areas with divergent ecosystems: peri-urban (coastal Rabai) and rural (Rift Valley Kerio Valley) in Kenya, survival rate was estimated by parity in Ae. simpsoni s.l. mosquitoes sampled using CO2-baited BG Sentinel traps. We then applied PCR targeting the nuclear internal transcribed spacer 2 (ITS2), region followed by sequencing and phylogenetic analytics to identify the sibling species in the Ae. simpsoni complex among parous and blood fed cohorts. Our results show that Ae. bromeliae was the most dominant sub-species in both areas, exhibiting high survival rates, human blood-feeding, and potentially, high vectorial capacity for pathogen transmission. We document for the first time the presence of Ae. lilii in Kenya and potentially yet-to-be described species in the complex displaying human feeding tendencies. We also infer a wide host feeding range on rodents, reptile, and domestic livestock besides humans especially for Ae. bromeliae. This feeding trend could likely expose humans to various zoonotic pathogens. Taken together, we highlight the utility of genotype-based analyses to generate precision surveillance data of vector populations for enhanced disease risk prediction and to guide cost-effective interventions (e.g. YF vaccinations).

Andean lupin (Lupinus mutabilis) oil is rich in monounsaturated (54.2%) and polyunsaturated (28.5%) fatty acids but has a ω-3:ω-6 ratio (1:9.2) above the recommended values for human health. Sacha inchi (Plukenetia volubilis) oil presents a high polyunsaturated fatty acid content (linolenic 47.2% and linoleic 34.7%), along a ω-3:ω-6 ratio (1:0.74) good for human consumption. The objective of this research was to study the physico-chemical properties and oxidative stability of tarwi and sacha inchi oil blends (1:4, 1:3, 1:1, 3:1 and 4:1 w:w) with suitable ω-3:ω-6 ratios. All blends showed ω-3:ω-6 ratios between 1:0.8 and 1:1.9, acceptable from a nutritional point of view, and high total tocopherols’ content (1834–688 mg/kg), thanks to sacha inchi. The oxidative stability index (OSI) of the mixtures by the Rancimat method at 120 °C ranged from 0.46 to 8.80 h. The shelf-life of 1:1 tarwi/sacha inchi oil blend was 1.26 years; its entropy (−17.43 J/mol), enthalpy (107.04 kJ/mol), activation energy (110.24 kJ/mol) and Gibbs energy (113.76 kJ/mol) suggest low oxidation reaction rates and good stability. Hence, balanced blends of tarwi/sacha inchi oils can achieve optimal nutritional properties and enhanced shelf-life.

Jingmen tick virus (JMTV) is an arbovirus with a multisegmented genome related to those of unsegmented flaviviruses. The virus first described in Rhipicephalus microplus ticks collected in Jingmen city (Hubei Province, China) in 2010 is associated with febrile illness in humans. Since then, the geographic range has expanded to include Trinidad and Tobago, Brazil, and Uganda. However, the ecology of JMTV remains poorly described in Africa. We screened adult ticks (n = 4550, 718 pools) for JMTV infection by reverse transcription polymerase chain reaction (RT-PCR). Ticks were collected from cattle (n = 859, 18.88%), goats (n = 2070, 45.49%), sheep (n = 1574, 34.59%), and free-ranging tortoises (Leopard tortoise, Stigmochelys pardalis) (n = 47, 1.03%) in two Kenyan pastoralist-dominated areas (Baringo and Kajiado counties) with a history of undiagnosed febrile human illness. Surprisingly, ticks collected from goats (0.3%, 95% confidence interval (CI) 0.1–0.5), sheep (1.8%, 95% CI 1.2–2.5), and tortoise (74.5%, 95% CI 60.9–85.4, were found infected with JMTV, but ticks collected from cattle were all negative. JMTV ribonucleic acid (RNA) was also detected in blood from tortoises (66.7%, 95% CI 16.1–97.7). Intragenetic distance of JMTV sequences originating from tortoise-associated ticks was greater than that of sheep-associated ticks. Phylogenetic analyses of seven complete-coding genome sequences generated from tortoise-associated ticks formed a monophyletic clade within JMTV strains from other countries. In summary, our findings confirm the circulation of JMTV in ticks in Kenya. Further epidemiological surveys are needed to assess the potential public health impact of JMTV in Kenya.

El hepatocarcinoma es la segunda causa de muerte en el mundo relacionada con el cáncer y en nuestro país encontramos a pacientes con grandes tumores hepáticos que son irresecables y solo son tributarios de tratamientos paliativos con escasa sobrevida, sin embargo con una adecuada selección de pacientes en equipos multidisciplinarios podemos ofrecerle una hepatectomia extendida a muchos de estos paciente, por lo que presentamos el caso de un paciente adulto joven con hepatitis B y hepatocarcinoma gigante al que le realizamos una hepatectomia izquierda extendida son una sobrevida libre de enfermedad a los 14 meses de operado.

Seed and peel avocado (Persea Americana) are agro-industrial residues whose structure presents an important quantity of source of polyphenolic components which can be obtained by various extraction methods. Response surface methodology (RSM) and the artificial neural network (ANN) were used to model and optimize the conditions of ultrasound-assisted extraction (UAE) (25 W/L) with respect to temperature (40 - 60 °C), concentration of ethanol/water (30% - 60%) and extraction time (40 - 80 min) in obtaining phenolic from avocado residues. RSM and ANN allowed finding an optimal phenolic content for seeds (145.170 - 146.569 mg GAE/g; 49 °C, 41.2% and 65.5 - 65.1 min) and peels (124.050 - 125.187 mg GAE/g; 50.9 °C, 49.5% and 61.8 min). The models estimated between predicted and experimental values were significant (p < 0.05), presenting a high correlation (R2> 0.9907) and a low root mean square error for the prediction of phenolics (RMSE < 0.9437 mg GAE/g). The results of this study allow the design of efficient, economic and ecologically friendly extraction procedures in the industry for obtaining bioactive metabolites from avocado residues.

La incidencia de neoplasias malignas sincrónicas primarias de hígado es extremadamente baja. Reportamos el caso de una paciente de 59 años con antecedente de hepatitis B sin seguimiento, que ingresó a nuestra institución por el hallazgo incidental de dos tumoraciones hepáticas. La paciente fue sometida a segmentectomía hepática VII y VIII, cuya evaluación histopatológica reveló un hepatocarcinoma y un colangiocarcinoma, respectivamente. El antecedente de enfermedad hepática crónica por hepatitis B incrementa el riesgo de desarrollar neoplasias malignas primarias en hígado, por lo tanto, estos pacientes deben ser evaluados periódicamente con estudios de imágenes.

Present work proposes the substitution of traditional food stabilizers from the hydrocolloids of algae. Hydrocolloids from Nostoc commune and Nostoc sphaericum were extracted, characterized by infrared spectroscopy, and modelled their rheological behavior. The dried extract samples were dried by lyophilization and hot air and diluted in water at concentrations of 0.15% and 0.25% and lastly stored at different temperatures (7 – 80 °C). The infrared indicated C – O – C vibrations corresponding to the glucose cycle (1020 cm-1) and C = O of carboxyl groups (1950 cm-1) are proper of hydrocolloids. Rheological models of Bingham, Ostwald and Herschel-Bulkley confirmed that the Nostoc coomune species presents a higher coefficient of plastic viscosity (η) and coefficient of consistency (k) than Nostoc commune; the freeze drying method had a positive influence and significant on these results (p < 0.05). Likewise, the hydrocolloid samples were diluted under nectar conditions (12 °Brix and 4.5 pH) taking carboxymethyl cellulose (CMC) as a control, finding that there is less influence of temperature on the consistency index of hydrocolloids in the order of Nostoc sphericum < Nostoc commune < CMC. It is concluded that the application of hydrocolloids of the genus nosctoc can be used as additives in the preparation of nectar, maintaining their rheological properties.

Abstract Background Nitric oxide (NO) regulates processes involved in sepsis progression, including vascular and immune function. NO is generated by nitric oxide synthases (NOS) from L-arginine. Cellular L-arginine uptake is inhibited by symmetric dimethylarginine (SDMA) and asymmetric dimethylarginine (ADMA) is a competitive inhibitor of NOS. Increased inhibitor blood concentrations lead to reduce NO bioavailability. The aim of this study was to determine whether plasma concentrations of SDMA and ADMA are markers for sepsis survival. Method This prospective, single center study involved 120 ICU patients with sepsis. Plasma SDMA and ADMA were measured on admission (day 1), day 3 and day 7 by mass spectrometry together with other laboratory markers. The sequential organ failure assessment (SOFA) score was used to evaluate sepsis severity. Survival was documented until day 28. Groups were compared using the Mann-Whitney U test, chi-squared test or non-parametric analysis of variance (ANOVA). Mortality was assessed using Kaplan-Meier curves and compared using the log-rank test. Specific risk groups were identified using a decision tree algorithm. Results Median plasma SDMA and ADMA levels were significantly higher in non-survivors than in survivors of sepsis: SDMA 1.14 vs. 0.82 μmol/L (P = 0.002) and ADMA 0.93 vs. 0.73 μmol/L (P = 0.016). ANOVA showed that increased plasma SDMA and ADMA concentrations were significantly associated with SOFA scores. The 28-day mortality was compared by chi-square test: for SDMA the mortality was 12% in the lower, 25% in the intermediate and 43% in the 75th percentile (P = 0.018); for ADMA the mortality was 18–20% in the lower and intermediate but 48% in the 75th percentile (P = 0.006). The highest mortality (61%) was found in patients with plasma SDMA > 1.34 together with ADMA levels > 0.97 μmol/L. Conclusions Increased plasma concentrations of SDMA and ADMA are associated with sepsis severity. Therefore, our findings suggest reduced NO bioavailability in non-survivors of sepsis. One may use individual SDMA and ADMA levels to identify patients at risk. In view of the pathophysiological role of NO we conclude that the vascular system and immune response are most severely affected when SDMA and ADMA levels are high.

Contents [ABSTRACT FROM AUTHOR]