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1.
Science ; 379(6630): 361-368, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36701471

RESUMO

Triterpenes with complex scaffold modifications are widespread in the plant kingdom. Limonoids are an exemplary family that are responsible for the bitter taste in citrus (e.g., limonin) and the active constituents of neem oil, a widely used bioinsecticide (e.g., azadirachtin). Despite the commercial value of limonoids, a complete biosynthetic route has not been described. We report the discovery of 22 enzymes, including a pair of neofunctionalized sterol isomerases, that catalyze 12 distinct reactions in the total biosynthesis of kihadalactone A and azadirone, products that bear the signature limonoid furan. These results enable access to valuable limonoids and provide a template for discovery and reconstitution of triterpene biosynthetic pathways in plants that require multiple skeletal rearrangements and oxidations.


Assuntos
Citrus , Genes de Plantas , Limoninas , Melia azedarach , Citrus/enzimologia , Citrus/genética , Limoninas/metabolismo , Melia azedarach/enzimologia , Melia azedarach/genética , Vias Biossintéticas/genética
2.
Sensors (Basel) ; 22(15)2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35957267

RESUMO

Within Industry 4.0, drones appear as intelligent devices that have brought a new range of innovative applications to the industrial sector. The required knowledge and skills to manage and appropriate these technological devices are not being developed in most universities. This paper presents an unmanned aerial vehicle (UAV)-based smart educational mechatronics system that makes use of a motion capture (MoCap) laboratory and hardware-in-the-loop (HIL) to teach UAV knowledge and skills, within the Educational Mechatronics Conceptual Framework (EMCF). The macro-process learning construction of the EMCF includes concrete, graphic, and abstract levels. The system comprises a DJI Phantom 4, a MoCap laboratory giving the drone location, a Simulink drone model, and an embedded system for performing the HIL simulation. The smart educational mechatronics system strengthens the assimilation of the UAV waypoint navigation concept and the capacity for drone flight since it permits the validation of the physical drone model and testing of the trajectory tracking control. Moreover, it opens up a new range of possibilities in terms of knowledge construction through best practices, activities, and tasks, enriching the university courses.


Assuntos
Aeronaves , Dispositivos Aéreos não Tripulados , Humanos , Organotiofosfatos
3.
Sci Adv ; 7(50): eabj6538, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34878851

RESUMO

There is a need for additional rapidly scalable, low-cost vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to achieve global vaccination. Aluminum hydroxide (alum) adjuvant is the most widely available vaccine adjuvant but elicits modest humoral responses. We hypothesized that phosphate-mediated coanchoring of the receptor binding domain (RBD) of SARS-CoV-2 together with molecular adjuvants on alum particles could potentiate humoral immunity by promoting extended vaccine kinetics and codelivery of vaccine components to lymph nodes. Modification of RBD immunogens with phosphoserine (pSer) peptides enabled efficient alum binding and slowed antigen clearance, leading to notable increases in germinal center responses and neutralizing antibody titers in mice. Adding phosphate-containing CpG or saponin adjuvants to pSer-RBD:alum immunizations synergistically enhanced vaccine immunogenicity in mice and rhesus macaques, inducing neutralizing responses against SARS-CoV-2 variants. Thus, phosphate-mediated coanchoring of RBD and molecular adjuvants to alum is an effective strategy to enhance the efficacy of SARS-CoV-2 subunit vaccines.

4.
Nat Commun ; 12(1): 4817, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376662

RESUMO

Engineered ectodomain trimer immunogens based on BG505 envelope glycoprotein are widely utilized as components of HIV vaccine development platforms. In this study, we used rhesus macaques to evaluate the immunogenicity of several stabilized BG505 SOSIP constructs both as free trimers and presented on a nanoparticle. We applied a cryoEM-based method for high-resolution mapping of polyclonal antibody responses elicited in immunized animals (cryoEMPEM). Mutational analysis coupled with neutralization assays were used to probe the neutralization potential at each epitope. We demonstrate that cryoEMPEM data can be used for rapid, high-resolution analysis of polyclonal antibody responses without the need for monoclonal antibody isolation. This approach allowed to resolve structurally distinct classes of antibodies that bind overlapping sites. In addition to comprehensive mapping of commonly targeted neutralizing and non-neutralizing epitopes in BG505 SOSIP immunogens, our analysis revealed that epitopes comprising engineered stabilizing mutations and of partially occupied glycosylation sites can be immunogenic.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Formação de Anticorpos/imunologia , Anticorpos Anti-HIV/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/ultraestrutura , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/ultraestrutura , Microscopia Crioeletrônica/métodos , Epitopos/química , Epitopos/imunologia , Epitopos/metabolismo , Glicosilação , Anticorpos Anti-HIV/química , Anticorpos Anti-HIV/ultraestrutura , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , HIV-1/genética , HIV-1/imunologia , HIV-1/metabolismo , Humanos , Macaca mulatta , Modelos Moleculares , Conformação Proteica , Produtos do Gene env do Vírus da Imunodeficiência Humana/ultraestrutura
5.
Sensors (Basel) ; 20(18)2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32933223

RESUMO

In this research, we focus on the use of Unmanned Aerial Vehicles (UAVs) for the delivery of payloads and navigation towards safe-landing zones, specifically on the modeling of flight dynamics of lightweight vehicles denoted Precision Aerial Delivery Systems (PADSs). While a wide range of nonlinear models has been developed and tested on high-end applications considering various degrees of freedom (DOF), linear models suitable for low-cost applications have not been explored thoroughly. In this study, we propose and compare two linear models, a linearized version of a 6-DOF model specifically developed for micro-lightweight systems, and an alternative model based on a double integrator. Both linear models are implemented with a sensor fusion algorithm using a Kalman filter to estimate the position and attitude of PADSs, and their performance is compared to a nonlinear 6-DOF model. Simulation results demonstrate that both models, when incorporated into a Kalman filter estimation scheme, can determine the flight dynamics of PADSs during smooth flights. While it is validated that the double integrator model can adequately operate under the proposed estimation scheme for up to small acceleration changes, the linearized model proves to be capable of reproducing the nonlinear model characteristics even during moderately steep turns.


Assuntos
Aeronaves , Algoritmos , Dinâmica não Linear , Simulação por Computador
6.
J Therm Biol ; 92: 102695, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32888579

RESUMO

Montane habitats exhibit a high degree of thermal heterogeneity, and thus provide considerable thermoregulatory challenges for ectotherms. Comparative analyses provide an opportunity to understand how variation in abiotic factors (e.g., operative temperatures, thermal quality) can affect life history traits within species. We studied the thermal ecology of three populations of the rattlesnake Crotalus triseriatus inhabiting different volcanoes in the central region of Mexico using the Hertz et al. (1993) protocol. The average body temperature of dusky rattlesnakes from the three study sites was 22.4 °C; mean active body temperature was higher in site 2 than in sites 1 and 3, but no differences between females, males and juveniles nor an interaction among site and sex was found. The thermal quality was low in the three sites, particularly in sites 1 and 3. Thermoregulation accuracy statistically differed among populations: individuals from site 2 were more accurate thermoregulating, while individuals from site 1 were the least accurate. Compared to other snakes, dusky rattlesnakes can be considered as a eurythermic species, which can often be active at relatively low body temperatures.


Assuntos
Crotalus/fisiologia , Animais , Temperatura Corporal , Regulação da Temperatura Corporal , Ecossistema , Feminino , Masculino , México , Temperatura
7.
Sensors (Basel) ; 20(5)2020 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-32182659

RESUMO

Humanity is currently experiencing one of the short periods of transition thanks to novel sensing solutions for smart cities that bring the future to today. Overpopulation of cities demands the development of solid strategic plannings that uses infrastructure, innovation, and technology to adapt to rapid changes. To improve mobility in cities with a larger and larger vehicle fleet, a novel sensing solution that is the cornerstone of a smart parking system, the smart vehicular presence sensor (SPIN-V, in its Spanish abbreviation), is presented. The SPIN-V is composed of a small single-board computer, distance sensor, camera, LED indicator, buzzer, and battery and devoted to obtain the status of a parking space. This smart mobility project involves three main elements, namely the SPIN-V, a mobile application, and a monitoring center, working together to monitor, control, process, and display the parking space information in real-time to the drivers. In addition, the design and implementation of the three elements of the complete architecture are presented.

8.
Sensors (Basel) ; 21(1)2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33383917

RESUMO

This paper presents the design and development of an IoT device, called MEIoT weather station, which combines the Educational Mechatronics and IoT to develop the required knowledge and skills for Industry 4.0. MEIoT weather station connects to the internet, measures eight weather variables, and upload the sensed data to the cloud. The MEIoT weather station is the first device working with the IoT architecture of the National Digital Observatory of Intelligent Environments. In addition, an IoT open platform, GUI-MEIoT, serves as a graphic user interface. GUI-MEIoT is used to visualize the real-time data of the weather variables, it also shows the historical data collected, and allows to export them to a csv file. Finally, an OBNiSE architecture application to Engineering Education is presented with a dynamic system case of study that includes the instructional design carried out within the Educational Mechatronics Conceptual Framework (EMCF) to show the relevance of this proposal. This work main contribution to the state of art is the design and integration of the OBNiSE architecture within the EMCF offering the possibility to add more IoT devices for several smart domains such as smart campus, smart cities, smart people and smart industries.

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