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Abstract Background Taenia solium, T. asiatica and T. saginata tapeworms cause human taeniasis and are the origin of porcine and bovine cysticercosis. Furthermore, T. solium eggs can cause human cysticercosis, with neurocysticercosis being the most serious form of the disease. These helminth infections are neglected tropical diseases and are endemic in several countries in the Americas, Asia and Africa. As a result of globalization, migration in particular, the infections have been extending to non-endemic territories. Species-specific diagnosis of taeniasis is subject to drawbacks that could be resolved using molecular approaches. In the present study, conventional and real-time amplification protocols (cPCR and qPCR) based on the T. saginata HDP2 sequence were applied in the differential diagnosis of taeniasis (T. saginata, T. solium) in both fecal samples and proglottids expelled by patients. The HDP2 homolog in T. solium was cloned and characterized. Results Semi-nested cPCR and qPCR (Sn-HDP2 cPCR and Sn-HDP2 qPCR) amplified T. saginata and T. solium DNA, with an analytical sensitivity of 40 and 400 fg, respectively, and identically in both protocols. Eighteen taeniasis patients were diagnosed directly with T. saginata or T. solium, either from proglottids or fecal samples with/without eggs (detected using microscopy), based on the optimized Sn-HDP2 qPCR. After cloning, the T. solium HDP2 homolog sequence was confirmed to be a ribosomal sequence. The HDP2 fragment corresponded to a non-transcribed sequence/external transcribed repeat (NTS/ETS) of ribosomal DNA. Compared with the T. saginata HDP2 homolog, the T solium HDP2 sequence lacked the first 900 nt at the 5′ end and showed nucleotide substitutions and small deletions. Conclusions Sn-HDP2 cPCR and Sn-HDP2 qPCR were set up for the diagnosis of human taeniasis, using proglottids and fecal samples from affected patients. The new Sn-HDP2 qPCR protocol was the best option, as it directly differentiated T. saginata from T. solium. The diagnosis of an imported T. solium-taeniasis case and nine European T. saginata cases was relevant. Finally, the cloning and sequencing of the T. solium HDP2 fragment confirmed that HDP2 was part of a ribosomal unit.

Aunque es bien conocida la variación estacional del patrón termohalino en el Golfo de Panamá, la distribución espacial de éstas características es prácticamente desconocida. En vista de ello, hemos utilizado la Base de Datos Oceanográficos del Océano Mundial (WOD01) para describir la variabilidad de la estructura termohalina en el Golfo de Panamá durante la temporada lluviosa y en la temporada seca cuando ocurre el fenómeno de afloramiento. Se seleccionaron los datos correspondientes a dos cruceros oceanográficos que presentan la mayor densidad en sitios de recolecta de muestras durante noviembre de 1967 (temporada lluviosa) y marzo de 1933 (temporada seca). Se utilizó el paquete de programas Ocean Data View para leer la información en WOD01, formar una colección datos y efectuar el análisis de los perfiles oceanográficos. Los resultados indican que la distribución de la temperatura superficial del mar en el Golfo de Panamá es significativamente diferente entre la temporada lluviosa y la temporada seca (Prueba-z = 24, p < 0.01). Durante la temporada lluviosa, las condiciones superficiales son bastantes homogéneas con temperaturas cálidas (> 27.5° C) y salinidad diluida (< 31 psu), por efecto de las lluvias. Durante la temporada seca el agua superficial es más fría (< 21° C) y más salina (> 34 psu). En la sección transversal promedio del golfo, la termoclina (definida como la isoterma de 20° C), se hunde hacia el lado Oeste y por el contrario, prácticamente rompe en la superficie en el lado Este del golfo, donde el afloramiento es más intenso.

In this work, a Detect and Avoid system is presented for the autonomous navigation of Unmanned Aerial Vehicles (UAVs) in Urban Air Mobility (UAM) applications. The current implementation is designed for the operation of multirotor UAVs in UAM corridors. During the operations, unauthorized flying objects may penetrate the corridor airspace posing a risk to the aircraft. In this article, the feasibility of using a solid-state LiDAR (Light Detecting and Ranging) sensor for detecting and positioning these objects was evaluated. For that purpose, a commercial model was simulated using the specifications of the manufacturer along with empirical measurements to determine the scanning pattern of the device. With the point clouds generated by the sensor, the system detects the presence of intruders and estimates their motion to finally compute avoidance trajectories using a Second Order Cone Program (SOCP) in real time. The method was tested in different scenarios, offering robust results. Execution times were of the order of 50 milliseconds, allowing the implementation in real time on modern onboard computers.

In this work, a real-time collision avoidance algorithm was presented for autonomous navigation in the presence of fixed and moving obstacles in building environments. The current implementation is designed for autonomous navigation between waypoints of a predefined flight trajectory that would be performed by an UAV during tasks such as inspections or construction progress monitoring. It uses a simplified geometry generated from a point cloud of the scenario. In addition, it also employs information from 3D sensors to detect and position obstacles such as people or other UAVs, which are not registered in the original cloud. If an obstacle is detected, the algorithm estimates its motion and computes an evasion path considering the geometry of the environment. The method has been successfully tested in different scenarios, offering robust results in all avoidance maneuvers. Execution times were measured, demonstrating that the algorithm is computationally feasible to be implemented onboard an UAV.

Reintroductions continue to be an important conservation action for endangered species. Until this, all reintroduction projects for Mhorr gazelle (Nanger dama mhorr) had remained at the stage where the animals live in fenced protected areas of different sizes. This study describes the first experience of reintroduction of a group of 24 Mhorr gazelle into the wild in the Safia Reserve, in Southern Morocco. The reintroduction was carried out in two phases: in the first one, the entire group was released; then, after an unexpected dogs attack event, part of them were kept safe until this problem was solved. Seven of the gazelles were monitored with telemetry collars, providing previously unavailable data on time allocation, daily rhythm of activity and social organization for the species in the wild. In addition, post-release movements revealed three patterns: during the first few days after release, small daily movements (average 2.78 km) close to the fence, followed by long-distance exploratory movements (up to 50 km) until establish territories; and finally, daily movements between established territories (average 8.39 km). Exceptional long distances (>50 km/day) were traveled after a poaching event. The study has also revealed the ability of the species to select and settle territories in favorable areas, after being kept for generations under captive or semi-captive conditions. However, their inability to recognize predators was demonstrated in an unexpected attack by dogs, resulting in the death of seven released gazelles. This mortality following the dog attack was favored, in part, because the released gazelle remained close to the fence, and therefore suggests that the release procedure should be revised, especially when there are predators in the release site. This study has confirmed that dogs as predators and poaching continue to be the main threat to reintroduction projects in Southern Morocco. Keywords: Reintroduction, Nanger dama mhorr, Mhorr gazelle, Conservation, Southern Morocco

In this work, the effect of the test configuration and temperature on the mechanical behaviour of cemented carbides (WC-Co) with different carbide grain sizes (dWC) and cobalt volume fractions (VCo), implying different binder mean free paths (λCo), was studied. The mechanical strength was measured at 600 °C with bar-shaped specimens subjected to uniaxial four-point bending (4PB) tests and with disc specimens subjected to biaxial ball-on-three-balls (B3B) tests. The results were analysed within the frame of the Weibull theory and compared with strength measurements performed at room temperature under the same loading conditions. A mechanical degradation greater than 30% was observed when the samples were tested at 600 °C due to oxidation phenomena, but higher Weibull moduli were obtained as a result of narrower defect size distributions. A fractographic analysis was conducted with broken specimens from each test configuration. The number of fragments (Nf) and the macroscopic fracture surface were related to the flexural strength and fracture toughness of WC-Co. For a given number of fragments, higher mechanical strength values were always obtained for WC-Co grades with higher KIc. The observed differences were discussed based on a linear elastic fracture mechanics (LEFM) model, taking into account the effect of the temperature and microstructure of the cemented carbides on the mechanical strength.

Human babesiosis is a zoonosis primarily transmitted through Ixodes ticks and alternatively by routes such as blood transfusions from asymptomatic donors. We report the first case of human babesiosis caused by Babesia divergens in a patient with HIV. This study also focuses on elucidating the possible transmission route of infection in this patient, who received numerous blood transfusions but showed patent symptoms only after splenectomy. A battery of detection tools along with a novel Western-Blot Assay and Enzyme Linked Immunosorbent Assay using the major surface protein of B. divergens (Bd37) as a target were used to evaluate the presence of B. divergens or antibodies against the parasite in samples from the patient and the blood donors involved in this case. A retrospective study of the humoral status against the parasite revealed B. divergens IgG antibodies in one of the implicated donors, but also showed that the patient had been already exposed to the parasite before any transfusion. Thus, this analysis of natural and transfusion transmission routes suggests a pre-existing subclinical babesiosis in the patient.

Rational use of multivariate statistics, modeling and biological knowledge can help the researcher to design a tested crucial experiment and to reach consistent conclusions. This work based on this statement and on a previous report of in vitro conservation of D. alata. It aims to apply some multivariate statistical techniques to determine the main factors which contribute to differentiate and to group the treatments. The most suitable factors for the preservation of genetic resources of this species were also defined. The D. alata conservation process was evaluated by principal component analysis at 9 months. Percentage of survival, phenolization, explants with leaves, rooting, sprouting and leaf senescence, stem length, root number and number of novo nodes per explants were the analyzed variables. Results showed that the survival rate variables, percentage of explants with leaves, stem length, number of novo nodes and number of roots express much of the observed variation in the processes of growth and development. On the other hand, deterioration and aging of in vitro nodal segments buds is better explained by the percentage of phenolization variables and leaf senescence. The best treatments for in vitro conservation of D. alata based on variables with higher contribution in the multivariate statistical analysis, corresponded to the culture medium D - 571 with the 1.5% mannitol, 0.1 or 1 mg.l-1 BA and 2 g.l-1 of activated charcoal. Keywords: activated charcoal, benzylaminopurine, cluster analysis, principal components, mannitol, yam