Asia is considered an important source of influenza A virus (IAV) pandemics, owing to large, diverse viral reservoirs in poultry and swine. However, the zoonotic origins of the 2009 A/H1N1 influenza ...pandemic virus (pdmH1N1) remain unclear, due to conflicting evidence from swine and humans. There is strong evidence that the first human outbreak of pdmH1N1 occurred in Mexico in early 2009. However, no related swine viruses have been detected in Mexico or any part of the Americas, and to date the most closely related ancestor viruses were identified in Asian swine. Here, we use 58 new whole-genome sequences from IAVs collected in Mexican swine to establish that the swine virus responsible for the 2009 pandemic evolved in central Mexico. This finding highlights how the 2009 pandemic arose from a region not considered a pandemic risk, owing to an expansion of IAV diversity in swine resulting from long-distance live swine trade.
Adenomyosis is linked to infertility, but the mechanisms behind this relationship are not clearly established. Similarly, the impact of adenomyosis on ART outcome is not fully understood. Our main ...objective was to use ultrasound imaging to investigate adenomyosis prevalence and severity in a population of infertile women, as well as specifically among women experiencing recurrent miscarriages (RM) or repeated implantation failure (RIF) in ART.
Cross-sectional study conducted in 1015 patients undergoing ART from January 2009 to December 2013 and referred for 3D ultrasound to complete study prior to initiating an ART cycle, or after ≥3 IVF failures or ≥2 miscarriages at diagnostic imaging unit at university-affiliated private IVF unit. Adenomyosis was diagnosed in presence of globular uterine configuration, myometrial anterior-posterior asymmetry, heterogeneous myometrial echotexture, poor definition of the endometrial-myometrial interface (junction zone) or subendometrial cysts. Shape of endometrial cavity was classified in three categories: 1.-normal (triangular morphology); 2.- moderate distortion of the triangular aspect and 3.- "pseudo T-shaped" morphology.
The prevalence of adenomyosis was 24.4 % (n = 248) 29.7 % (94/316) in women aged ≥40 y.o and 22 % (154/699) in women aged <40 y.o., p = 0.003). Its prevalence was higher in those cases of recurrent pregnancy loss 38.2 % (26/68) vs 22.3 % (172/769), p < 0.005 and previous ART failure 34.7 % (107/308) vs 24.4 % (248/1015), p < 0.0001. The presence of adenomyosis has been shown to be associated to endometriosis 35.1 % (34/97). Adenomyosis was diagnosed as a primary finding "de novo" in 80.6 % (n = 200) of the infertile patients. The impact on the uterine cavity was mild, moderate and severe in 63.7, 22.6 and 10.1 % of the cases, respectively.
Our results indicate that adenomyosis is a clinical condition with a high prevalence that may affect the reproductive results. The described severity criteria may help future validating studies for better counseling of infertile couples.
This paper focuses on the influence of the step drill bit geometry on the damage induced during drilling Carbon Fiber Reinforced Polymer materials (CFRPs). Step geometry designed with the aim of ...avoiding composite damage in CFRPs drilling, is compared to conventional twist configuration. Despite the reduction of thrust force and torque observed when using the step drill, the delamination was only reduced at low feed rates. A numerical model developed for the step geometry was validated with experimental data demonstrating its ability to predict thrust force and delamination for different values of feed rate and cutting speed. Numerical model allowed the development of a parametrical study. Finally, using a response surface methodology a mechanistic model and surface diagrams have been presented in order to help in the selection of optimum variables minimizing drilling induced damage.
A three-layered membrane based on poly(ethylene-co-vinyl acetate) (EVA) and hydrolyzed EVA–poly(ethylene-co-vinyl alcohol) (EVOH), was elaborated by the surface hydrolysis of a dense EVA membrane. ...Because of the chemical modifications, the three-layered EVOH/EVA/EVOH membrane was characterized by the particular microstructure (amorphous EVA and semicrystalline EVOH) and the tunable hydrophilic/hydrophobic balance. Also, these modifications led to the membrane with the selective barrier properties compared with the pure EVA and completely hydrolyzed EVOH membranes. The water barrier behavior was related to the strong hydrogen-bond interactions of water and vinyl alcohol groups, whereas the weak chemical interactions were revealed for gases (N2 and O2). Furthermore, the influence of the polymer rubbery or glassy state on the permeation kinetics was established. In the case of the three-layered membrane, the considerably high selectivity values were obtained for H2O/O2 (∼11 900) and H2O/N2 (∼48 000) at 25 °C. In addition to these highly selective properties, the three-layered structure does not present delamination features due to its elaboration procedure. Thus, these new layered membranes are very promising as selective materials for the water and gas separation and can be potentially used in food packaging or for the gas dehydration.
West Nile virus (WNV) is an emerging vector-borne arbovirus with a zoonotic life-cycle whose main reservoir hosts are birds. In humans and horses, WNV infections rarely result in clinical disease but ...on occasions – depending on factors such as climatic conditions, insect communities and background immunity levels in local populations – they can lead to outbreaks that threaten public and animal health. We tested for the presence of WNV antibodies in 149 birds belonging to 32 different species. Samples were first tested using a bird-specific ELISA kit and then both positive and doubtful results were confirmed by neutralization tests using WNV and Usutu virus. WNV antibodies were confirmed in a resident Sylvia melanocephala juvenile, supporting the idea of local transmission of WNV in southern Spain in 2013. In addition, the serum from an adult blackbird (Turdus merula) showed neutralization of both WNV and Usutu virus. We discuss our results in light of the occurrence of WNV on horse farms in southern Spain in 2013.
•A simplified Artificial bird has been proved to behave as literature review studies.•Radial expansion of the artificial bird has been studied.•Induced force by the impact has been measured using a ...Hopkinson tube.•The four numerical models benchmarked reproduce the impact force measured.•Numerical models commonly used are not capable to predict the radial expansion.
This work shows a combined experimental-numerical research in bird impact. In order to perform the experimental tests, a artificial bird has been prepared and impacted against a Hopkinson tube in a wide range of impact velocities (70–200 m/s). The Hopkinson tube was designed in order to measure the induced force transmitted in the tube by the impact. This force could be used to compare different experimental tests and also to validate the numerical models proposed. In addition, the whole process of impact was recorded by means of high speed video cameras. The images captured allow to perform the analysis of the bird kinematics during the impact. Numerically, in order to reproduce the high deformations experienced by the artificial bird in the impact process, the Smooth Particle Hydrodynamics (SPH) technique has been used. Concerning the artificial bird material behaviour, four different models were employed, combining the two material models and two equations of state most used in the literature. The four cases have been compared with the experimental measurements and benchmarked. After the analysis of the results, it can be concluded that the combined experimental-numerical methodology proposed successfully can be used to study and validate the numerical models for simulating the behaviour of soft impactor when subjected to high velocity impacts. It can be seen that the normal impact forces induced by the impact are reproduced adequately for all the numerical models. However the radial spreading of the soft impactor is not reproduced as adequately as the other cases, especially in low velocity impacts. This effect can be important to reproduce the radial distribution of pressures and the secondary impacts produced by this radial expansion.
The present study numerically investigated the use of bimetallic tubes for concentrating solar energy applications. Specifically, a billboard receiver employing supercritical carbon dioxide (sCO2) as ...the heat transfer fluid is considered, with tubes made of stainless steel 316 and GRCop-84. Two- and three-layer tube configurations are compared, exploring the impact of more thermally conductive layer thickness and placement on temperature and stress fields. The findings demonstrate that the use of bimetallic tubes can effectively reduce temperature and stress in the receiver tubes. In light of the results, it can be concluded that the higher thermal conductivity of GRCop-84 leads to a more uniform temperature distribution, resulting in lower temperature peaks on the outer tube surface, and reduced maximum stresses. Furthermore, it has been found that the incident heat flux necessary to achieve the same temperature increment of sCO2 inside the panel is 1.7% lower in a two-layer tube configuration where GRCop-84 is placed in the outer layer. Besides, the stress in the 316 layer can be reduced up to 53.2% with the cited configuration. Nevertheless, it is observed that it is more beneficial to tube performance to place the more conductive layer inside, since it reduces stress in the GRCop-84 layer, and its compressive stress and corrosion-resistant properties help to avoid the risk of stress-corrosion-cracking. In a three-layer composite tube configuration, placing the more thermally conductive GRCop-84 layer close to the outer tube wall decreases the maximum temperature while increasing stress. The opposite effect is achieved by placing the more conductive layer closer to the inner tube wall. Overall, the results demonstrate the potential benefits of using bimetallic tubes for solar energy applications, when the layers have similar thicknesses, since their use can enhance the thermomechanical performance of conventional tubes made with one layer of 316 stainless steel. This fact has important implications for the design of efficient and reliable solar thermal systems.
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•New concept of flat-external tubular receiver with bimetallic composite tubes.•Two- and three-layer tubes reduce temperature, heat losses, and stress.•Copper alloy layer reduces temperature and uniformizes heat distribution.•Inner copper layer may prevent stress corrosion cracking and carburization problems.•Asymmetrical layers impact thermal and mechanical performance of 3-layer tubes.
A finite element numerical model for carbon/epoxy woven laminates has been used to predict residual velocity and damaged area when subjected to high impact velocities. Experiments using a gas gun ...were conducted to investigate the impact process and to validate the model, measuring the two variables previously indicated. A morphology analysis was also made to investigate the different breakage mechanisms that appear during the penetration process. The influence of the impact velocity and obliquity has been studied using the numerical tool, in a wide range of impact velocities and considering two impact angles, 0° and 45°.
CFRPs drilling is a common process in the aerospace industry carried out prior to components assembly. Machining induced damage leads to significant percentage of component rejection. Damage ...extension strongly depends on drilling geometry and cutting parameters. Fresh drill geometry changes with cutting time due to the wear progression and the risk for hole quality is enhanced as cutting progresses. The influence of wear on hole quality has been analyzed in the literature using mainly an experimental approach.
Simulation of drilling process is an effective method that can be used to optimize drill geometry and process parameters in order to control hole quality and analyze the drill wear evolution. In this paper a finite element model for drilling woven CFRPs, reproducing both fresh and worn tools, is presented. Two different point angles considering fresh and honned edge were modeled. A progressive intra-laminar failure model based on the Chang and Chang model is considered. Cohesive elements allowed the analysis of inter-laminar damage (delamination). The model demonstrated its ability to predict thrust force and delamination for different values of feed rate and cutting speed. Model predictions show the influence of tool geometry (including variations induced due to wear) on delamination.
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