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In this paper, a robust geometric navigation algorithm, designed on the special Euclidean group SE(3), of a quadrotor is proposed. The equations of motion for the quadrotor are obtained using the Newton–Euler formulation. The geometric navigation considers a guidance frame which is designed to perform autonomous flights with a convergence to the contour of the task with small normal velocity. For this purpose, a super twisting algorithm controls the nonlinear rotational and translational dynamics as a cascade structure in order to establish the fast and yet smooth tracking with the typical robustness of sliding modes. In this sense, the controller provides robustness against parameter uncertainty, disturbances, convergence to the sliding manifold in finite time, and asymptotic convergence of the trajectory tracking. The algorithm validation is presented through experimental results showing the feasibility of the proposed approach and illustrating that the tracking errors converge asymptotically to the origin.
Immigration federalism scholarship has established that state and local government policies can make federally defined immigration status more or less consequential. Drawing primarily on focus groups and interviews with 184 undocumented students attending the University of California, we suggest that institutional policies work alongside state and local efforts to mediate the consequences of illegality for undocumented students. We find that the Deferred Action for Childhood Arrivals program, state-funded financial aid policies, and university support programs all facilitate the integration of undocumented students by increasing access to higher education and enabling fuller participation. Although federal policies contribute to persistent barriers to academic engagement and professional development, we show that universities can intervene to improve educational experiences and opportunities. Ultimately, we argue that university policies are a key site for intervening in immigration policy and constructing immigrant illegality.
OBJECTIVES/SPECIFIC AIMS: The Title V Cooperative Project of the UPR-MSC and UCC has demonstrated that educational interventions in CTR are very effective in fulfilling the objective of promoting awareness, stimulate interest and increase the knowledge, skills and opportunities, to US, GS and F (participants) in CTR. METHODS/STUDY POPULATION: The training sessions (TS) offered through the Title V initiative have become an engine for the involvement in CTR for participants from higher education institutions island-wide. TS consisted of cycles –level 1 and 2–: Research Education Towards Opportunities (RETO,I,II) and Mentorship Offering Training Opportunities for Research (MOTOR,I,II), ending in the formation of the Clinical and Translational Mentoring Teams (CTMT)s, in which participants, paired by their research interests, were mentored by a well-established CT researchers in their research project, to be developed in the Intensive Development and Experiences in Advancement of Research and Increased Opportunities (IDEARIO). RESULTS/ANTICIPATED RESULTS: Up to date, 4 TS-level 1 and 2 TS-level 2 were offered. Eighty (80) participants completed level 1, distributed: 42 (52.5%) US in RETO, 21 (26.25%) GS and 17 (21.25%) F in MOTOR and 17 participants completed level 2, distributed: 4 (23.52%) US in RETO, 6 (25.29%) GS and 7 (41.17%) F in MOTOR. From which, 15, with 8 CT researchers, formed 5 CTMTs in different research areas – cardio, neuro, liver, renal, Zika–. DISCUSSION/SIGNIFICANCE OF IMPACT: US, GS and F were integrated in the active process throughout educational levels for their development in CTR.
Se presentan los primeros resultados obtenidos del estudio tecnológico-funcional de un conjunto de 55 cabezales de hachas o azuelas líticas asignadas al período prehispánico tardío (1500–360 años aP) de las Sierras de Córdoba, Argentina. A partir del análisis de sus atributos tecnológicos (peso, agudeza y largo de los filos, etc.) y de los rastros de uso utilizando aumentos de 20–50x, se argumenta que un número significativo de instrumentos fue utilizado para realizar tareas que involucraron el contacto con sedimentos abrasivos, probablemente para cortar y arrancar elementos leñosos del sotobosque a nivel del suelo. Una proporción del conjunto evidenció rastros de uso exclusivamente asociados al trabajo sobre maderas, como pulido y micro-estrías restringidas a la periferia de los filos. Se concluye que los grupos tardíos desarrollaron artefactos pulidos costosos para cumplir efectivamente con la apertura y mantenimiento de claros en el bosque serrano, ya sea para el cultivo, la construcción de viviendas o incrementar la capacidad reproductiva de plantas silvestres de las cuales dependían, entre otros motivos. De esta manera, comprender la función de las hachas o azuelas tardías es fundamental para discutir las actividades productivas y la modificación antrópica del paisaje propuesta para la región a fines del Holoceno.
OBJECTIVES/SPECIFIC AIMS: The University of Puerto Rico-Medical Sciences Campus and Universidad Central del Caribe, through the Title V Cooperative Project, devised a clinical and translational research (CTR) platform to pipeline students/faculty of undergraduate health sciences programs into CTR. Educational interventions in CTR—introductory intervention (II) and Annual Symposium (AS)—were designed to promote awareness, stimulate interest of students and faculty in CTR. METHODS/STUDY POPULATION: In the II the participants (n=159) were surveyed before and after a presentation and panel discussion about CTR. In addition, after the sessions—plenary, panel, and workshop—about CTR, the participants of AS (n=42) were surveyed for satisfaction and learning experience in CTR. RESULTS/ANTICIPATED RESULTS: Most participants of the II, 134 (84.3%) were students. In total, 58 (58, 36.5%) completed the post II survey. Of these, 53.4% satisfactorily defined the CTR concept Versus only 31.0% that could define CTR in the pre survey, 47 (81.7%) were unable to identify a CTR researcher and 45 (78.3 %) expressed interest in learning about CTR. In total, 28 (28, 66.7%) participants of the AS completed the satisfaction survey, out of which 17 (60.6%) were students. One hundred percent (100%) agreed that the AS served as a vehicle to increase their knowledge in CTR. DISCUSSION/SIGNIFICANCE OF IMPACT: The educational interventions demonstrated to be an effective strategy to promote awareness and stimulate interest of students and faculty in CTR. In addition, the results obtained, provided valuable baseline information for the planning—development of training cycles in CTR.
While there are effective treatments for psychiatric disorders, many individuals with such disorders do not receive treatment and those that do often take years to get into treatment. Information regarding treatment contact failure and delay in Argentina is needed to guide public health policy and planning. Therefore, this study aimed to provide data on prompt treatment contact, lifetime treatment contact, median duration of treatment delays and socio-demographic predictors of treatment contact after the first onset of a mental disorder.
The Argentinean Study of Mental Health Epidemiology (EAESM) is a multistage probability sample representative of adults (aged 18+) living in large urban areas of Argentina. A total of 2116 participants were evaluated with the World Mental Health Composite International Diagnostic Interview to assess psychiatric diagnosis, treatment contact and delay.
Projections of cases that will make treatment contact by 50 years taken from a survival curve suggest that the majority of individuals with a mood (100%) or anxiety disorder (72.5%) in Argentina whose disorder persist for a sufficient period of time eventually make treatment contact while fewer with a substance disorder do so (41.6%). Timely treatment in the year of onset is rare (2.6% for a substance disorder, 14.6% for an anxiety disorder and 31.3% of those with a mood disorder) with mean delays between 8 years for mood disorders and 21 years for anxiety disorders. Younger cohorts are more likely to make treatment contact than older cohorts, whereas those with earlier ages of disorder onset are least likely to make treatment contact. Those with anxiety disorders and major depressive disorder are more likely to make treatment contact when they have comorbid disorders, whereas those with substance use disorders are less likely.
Argentina needs to implement strategies to get individuals with substance use disorders into treatment, and to reduce treatment delays for all, but particularly to target early detection and treatment among children and adolescents.
We describe the structure of the Ricci tensor on a locally homogeneous Lorentzian gradient Ricci soliton. In the non-steady case, we show that the soliton is rigid in dimensions 3 and 4. In the steady case we give a complete classification in dimension 3.
A 1.1-m reflectarray antenna has been designed, manufactured, and tested to fulfill the requirements of a satellite antenna in Ku-band that provides South-American coverage in Tx and Rx. The reflectarray cells consist of four dipoles for each polarization in two dielectric layers, selected because of their simplicity and high performance. The dipole dimensions are optimized in all the reflectarray cells to accomplish the prescribed radiation patterns, by iteratively calling an analysis routine based on method of moments in spectral domain and local periodicity. The measured radiation patterns of the manufactured antenna have been satisfactorily compared with simulations and with a three-layer reflectarray previously designed, manufactured, and tested for the same mission.
Ladle refining plays a key role in achieving the quality of the steel since in this reactor temperature and chemical composition is adjusted, elimination of non-metallic inclusions is performed, and also deoxidation and desulphurization are operations taking place in the refining process. Specifically, the metal-slag mass exchanges have not received much attention through scientific studies. In this work, a rigorous study on the mass exchange between metal and slag is presented through a scaled water physical model. In the model, thymol (playing the role of a solute such as sulfur) is added to the water (playing the role of steel) and silicon oil (playing the role of slag) picks up the thymol, while the ladle is agitated with the central injection of gas. The evolution of thymol concentration in time was measured. Also, a mathematical model was developed and cast into the commercial CFD code Fluent Ansys to represent the fluid flow phenomena and the mass transfer through the solution of the continuity equation, the turbulent momentum conservation equations and the species mass conservation equation. There is a good agreement between the measured and the computed results regarding the thymol concentration evolution in water and consequently the mathematical model was validated regarding the mass species metal-slag exchanges and it may be used to study metal-slag exchanges in the steel ladle such as deoxidation or desulphurization.
RR Lyrae variables are old (>10 Gyr) stars and, as such, they are useful probes of the earliest events of star formation in galaxies (Bernard et al. 2008, Martínez-Vázquez et al. 2016) as well as of the galaxy assembly process predicted by ΛCDM simulations of structure formation. In fact, the nature of the building-blocks of galaxies such as the Milky Way, and in particular, those of their stellar haloes, has been a matter of a substantial debate (Venn et al. 2004). Unlike other stellar tracers, RR Lyrae offer a snapshot of the stellar content present at the epoch when most of the merging action is predicted to have taken place, and thus they are ideal witnesses of this process.
The improvement in porcine embryo preservation and non-surgical embryo transfer (ET) procedures achieved in recent years represents essential progress for the practical use of ET in the pig industry. This study aimed to evaluate the effects of parity, weaning-to-estrus interval (WEI) and season on reproductive and embryonic parameters at day 6 after insemination of donor sows superovulated after weaning. The selection of donor sows was based on their reproductive history, body condition and parity. The effects of parity at weaning (2 to 3, 4 to 5 or 6 to 7 litters), season (fall, winter and spring), and WEI (estrus within 3 to 4 days), and their interactions on the number of corpus luteum, cysts in sows with cysts, number and quality of viable and transferable embryos, embryo developmental stage and recovery and fertilization rates were evaluated using linear mixed effects models. The analyses showed a lack of significant effects of parity, season, WEI or their interactions on any of the reproductive and embryonic parameters examined. In conclusion, these results demonstrate that fertilization rates and numbers of viable and transferable embryos collected at day 6 of the cycle from superovulated donor sows are not affected by their parity, regardless of the time of the year (from fall to spring) and WEI (3 or 4 days).
To assess quality of life of children and teenagers with recurrent respiratory papillomatosis, according to the evidence of infection by human papillomavirus types 6 and 11, compared with healthy volunteers and patients with chronic otitis media.
Participants and their parents completed the Pediatric Quality of Life Inventory 4.0.
Patients with recurrent respiratory papillomatosis and their parents reported lower quality of life than healthy subjects (p < 0.01), but similar quality of life to patients with chronic otitis media. Those with human papillomavirus type 11 showed the lowest scores among all participants (p < 0.05).
Young Mexican patients with recurrent respiratory papillomatosis and their parents perceive a poor quality of life, and they may experience limitations in interactions with their peers. Infection by human papillomavirus type 11 may increase the impact of the disease on quality of life.
Human milk oligosaccharides (HMO) are involved in many biological functions influencing infant health. Although HMO act locally at the intestine, recent evidence has demonstrated that HMO are partially incorporated into the systemic circulation of breast-fed infants. In the last few years, a large amount of research has been conducted using preclinical models to uncover new biological functions of HMO. The aim of this study was to evaluate the absorption and urine excretion of HMO in rats. We administered a single oral dose of the following HMO: 2'-fucosyllactose (2'-FL), 6'-sialyllactose and lacto-N-neotetraose at different concentrations to adult rats. The time course of absorption of HMO into the bloodstream and their appearance in urine was studied. Our results showed that rats, similar to human infants, are able to effectively absorb a portion of HMO from the intestine into plasma and to excrete them in urine. On the basis of this, we also conducted a specific kinetic absorption study with 2'-FL, the most predominant HMO in human milk, in 9–11-d-old rat pups. Our results confirmed that a significant amount of 2'-FL was absorbed into the systemic circulation and subsequently excreted in urine during lactation in rats in a dose-depended manner. We also found basal levels of these HMO in plasma and urine of adult rats as well as rat pups as a natural result of nursing. Our data suggest that the rat may be a useful preclinical model that provides new insights into the metabolism and functions of HMO.
Changes in the specialization of parasite–host interactions will be influenced by variations in host species composition. We evaluated this hypothesis by comparing the composition of bats and bat flies within a roost cave over one annual. Five bat and five bat fly species occupied the cave over the course of the study. Bat species composition was 40% different in the rainy season compared with the dry–cold and dry–warm seasons. Despite the incorporation of three new bat species into the cave during the rainy season, bat fly species composition was not affected by seasonality, since the bats that arrived in the rainy season only contributed one new bat fly species at a low prevalence. Bat–bat fly ecological networks were less specialized in the rainy season compared with the dry–cold and dry–warm seasons because of the increase of host overlap among bat fly species during this season. This study suggests that seasonality promote: (1) differences in host species composition, and (2) a reduction in the specialization of host–parasite ecological networks.
The Virginia opossum (Didelphis virginiana) is considered highly adaptable to anthropogenic disturbances; however, the genetic effects of disturbance on this marsupial have not been studied in wild populations in Mexico. Here we evaluated the genetic diversity of D. virginiana at sites with different levels of disturbance within the Highlands and Central Depression regions of Chiapas in southern Mexico. Twelve microsatellite loci were used and the results demonstrated moderate mean heterozygosity (He = 0.60; Ho = 0.50). No significant differences in heterozygosity were found among sites with different levels of disturbance in both regions (range Ho = 0.42–0.57). We observed low but significant levels of genetic differentiation according to disturbance level. The inbreeding coefficient did not differ significantly from zero, suggesting that low genetic differentiation in these environments may be associated with sufficient random mating and gene flow, a result associated with the high dispersal and tolerance characteristics of this marsupial. Our results for D. virginiana in this particular area of Mexico provide a foundation for exploring the impact of human disturbance on the genetic diversity of a common and generalist species.
We study W | Ta | CoFeB | MgO stacks for spin-orbit torque MRAM applications. A strong perpendicular magnetic anisotropy is obtained after annealing for CoFeB layer thickness of 0.9 nm or 1.2 nm and for specific W/Ta ratios, were the Ta layer thickness is between 0.3 nm and 1 nm. Furthermore, the desired high-spin orbit coupling β-phase of W is preserved even after annealing at 350°C. We argue that an efficient B getter, like Ta, is necessary for the coherent crystallization of the CoFeB | MgO interface that allows for the establishment of perpendicular magnetic anisotropy.