Extracting Visibility Information by Following Walls

This paper presents an analysis of a simple robot model, called Bitbot. The Bitbot has limited capabilities; it can reliably follow walls and sense a contact with a wall. Although the Bitbot does not have a range sensor or a camera, it is able to acquire visibility information from the environment, which is then used to solve a pursuit-evasion task. Our developments are centered on the characterization of the information the Bitbot acquires. At any given moment, due to the sensing uncertainty, the robot does not know the current state. In general, uncertainty in the state is one of the central issues in robotics; the Bitbot model serves as an example of how the notion of information space naturally handles uncertainty. We show that state estimation with the Bitbot is a challenging problem, related to the well-known open problem of characterizing visibility graphs in computational geometry. However, state estimation becomes unnecessary to the achievement of the Bitbot\u27s visibility tasks. We show how pursuit-evasion strategy is derived from a careful manipulation with histories of observations, and present analysis of the algorithm and experimental results

Associations between timing and quality of solid food introduction with infant weight-for-length z-scores at 12 months: Findings from the Nurture cohort

This study assesses associations of the timing and quality of solid foods introduced during infancy with weight-for-length (WFL) z-scores at 12 months within the Nurture cohort. Women from North Carolina self-reported sociodemographics, the timing and type of solid food introduction, and reasons for introducing solids; infant anthropometrics were measured every 3 months through 1 year (n = 666). Frequency (0–5x/day) infants consumed fruits and vegetables was used to compute a mean (4–12 months) healthy food score (HFS), and sweets, french fries, snacks, and ice cream was used to compute a mean unhealthy food score (UnHFS). Multivariable-adjusted generalized linear models were used to examine the relationship of early solid food introduction, HFS quartiles (Q), UnHFS quartiles, and interactions between these variables with WFL z-scores at 12 months (n = 449). Exploratory analyses evaluated WFL z-scores among 4 groups of infants with high/low HFS and high/low UnHFS. On average, mothers were 28 years with a pre-pregnancy BMI of 30.5 kg/m2; 65% were Non-Hispanic Black, and 59% had incomes z-scores. Infants in Q3 and Q4 of the UnHFS had higher WFL z-scores (0.75–0.79 ± 0.09) compared to infants in Q1 (0.42 ± 0.0.9), p \u3c 0.05. Frequent unhealthy food intake was associated with higher WFL z-scores at 12-months, underscoring the importance of reducing unhealthy food intake in the first year

Maternal Stress and Excessive Weight Gain in Infancy

Rapid weight gain in infancy increases the risk of developing obesity early in life and contributes significantly to racial and ethnic disparities in childhood obesity. While maternal perceived stress is associated with childhood obesity, little is known about the impact it has on infant weight gain. Therefore, this study explores the impact of maternal perceived stress on change in weight-for-length (WFL) z-scores and the risk of rapid weight gain in infancy. We conducted a secondary data analysis of the longitudinal Nurture birth cohort (n = 666). Most mothers in the cohort were non-Hispanic/Latinx Black (71.6%). About one-half of mothers had a body mass index (BMI) greater than 25 prior to pregnancy, were unemployed, and had a low income. Most infants in the cohort were born full-term and were of normal weight. Data were collected at 3-, 6-, 9-, and 12-months postpartum. At each assessment, mothers completed the Cohen’s Perceived Stress Scale (PSS), and research assistants weighed and measured each infant. Tertiles were used to compare mothers with high and low perceived stress. A mixed model analysis of repeated measures assessed the associations between baseline perceived stress and the change in infant WFL z-scores over time. Log-binomial models assessed the association between baseline perceived stress and rapid weight gain, defined as a change in WFL z-score \u3e 0.67 standard deviations from three to twelve months. Just under one-half of the infants (47%) experienced rapid weight gain between three and twelve months of age. Birthweight for gestational age (RR = 1.18, 95% CI = 1.08–1.29, p-value = 0.004), gestational age at birth (RR = 1.07, 95% CI = 1.01–1.14, p-value = 0.031), and weeks breastfed (0.99, 95% CI 0.99–1.00, p-value 0.044) were associated with risk of rapid weight gain in unadjusted analyses. WFL z-scores increased significantly over time, with no effect of perceived stress on change in WFL z-score or risk of rapid weight gain. Rapid weight gain in infancy was prevalent in this sample of predominately Black infants in the Southeastern US. We did not find evidence to support the hypothesis that maternal perceived stress influenced the risk of rapid weight gain. More work is needed to identify and assess the risk factors for rapid weight gain in infancy and to understand the role that maternal stress plays in the risk of childhood obesity so that prevention efforts can be targeted

Associations of less healthy snack food consumption with infant weight-for-length z-score trajectories: Findings from the Nurture cohort study

Little is known about the impact of less healthy snack foods on weight trajectories during infancy. This secondary analysis of data from the Nurture cohort explored prospective associations of less healthy snack foods with infant weight trajectories. Pregnant women were recruited and, upon delivery of a single live infant, 666 mothers agreed to participate. Mothers completed sociodemographic and infant feeding questionnaires, and infant anthropometrics were collected during home visits at 3, 6, 9, and 12 months. Less healthy snack food consumption was assessed by asking how frequently baby snacks and sweets were consumed each day during the previous three months. Multilevel growth curve models explored associations of baby snacks and sweets with infant weight-for-length (WFL) z-scores. On average, mothers were 27 years old, 71.5% were non-Hispanic Black, and 55.4% had household incomes of ≤$20,000/year. Consumption of less healthy snack foods increased during infancy with a median intake of 3.0 baby snacks/day and 0.7 sweets/day between 10 and 12 months. Growth curve models showed that infants who consumed sweets \u3e2 times/day had significantly higher WFL z-scores during the second half of infancy compared to infants who never consumed sweets. Less healthy snacks may contribute to the risk of obesity during infancy and promoting healthy snack food choices during this critical time is important

Pressurized Device for Mitigating Atrophy in Soleus During Long-Duration Spaceflight

A major concern with long duration spaceflight, skeletal muscle atrophy is most detrimental in lower limb musculature, particularly in muscles critical for proper gait, such as the soleus. The decline of muscle activation and the suppression of sensory input from plantar sole mechanoreceptors can add to the attenuation of skeletal muscle health during spaceflight. More specifically, inhibition of sensory input from sole receptors, such as with gravitational unloading, decreases selective activation, thereby negatively affecting muscle tone and inevitably resulting in lower limb atrophy. PURPOSE: To design, fabricate, and test a specialized boot with an insole that applies oscillating pneumatic pressure for set periods of time to augment neuromuscular activation of the soleus through the plantar sole\u27s mechanoreceptors, which may minimize atrophy of lower extremity muscles. METHODS: The custom boot was originally designed in three-dimensional modeling software (Solidworks Premium, Waltham, MA). Components of the boot included: a lightweight medical walking brace, Metro-ATmega circuit board, air pump and vacuum DC motor, force resistive sensor, and kPa sensor. The boot was programmed using C++ to allow the user to wear the boot for 20 minutes (oscillating continuously) at the start of every hour with an automatic timer for 6 hours per day. Surface electromyography (EMG) measured electrical activity in lower extremity muscles while wearing the boot. The location of all electrodes were determined according to the SENIAM project (Surface Electromyography for the Non-Invasive Assessment of Muscles): 1) for soleus, electrode placed at two-thirds of the line between the medial condyle of the femur to the medial malleolus; 2) for medial head of the gastrocnemius, electrode placed at one-third of the line between the head of the fibula and the heel; 3) for ground, electrode placed at the tibial tuberosity. Muscle activation of the gastrocnemius was measured to investigate any co-activation of nearby musculature on the posterior leg. RESULTS: Upon airbag inflation, the soleus exhibited the greatest amplitude (30 to 50 µV versus 5 to 15 µV) when the ankle attempted to plantarflex while maintaining a neutral position. When the airbags are inflated, the pressure output corresponds to approximately 111 kPa. When the airbags are deflated, the pressure output corresponds to approximately 66 kPa, creating a pressure difference of 45 kPa. During the 20 min runtime, the airbags take 3.3 sec to inflate and 3.0 sec to deflate, creating the oscillating effect. When fully charged, the battery can sustain one full, 6-hour session with each lasting 20 minutes. CONCLUSION: Pneumatic pressure integrated into a customized therapeutic walking boot may elicit neuromuscular activity in the lower extremity musculature, which indicates that the device may help in attenuating the negative neuromuscular adaptations in the soleus via afferent signaling

Keys to healthy family child care homes: Results from a cluster randomized trial

Early care and education settings, such as family child care homes (FCCHs), are important venues for children\u27s health promotion. Keys to Healthy Family Child Care Homes evaluated a FCCH-based intervention\u27s impact on children\u27s diet and physical activity. This study enrolled 496 children aged 1.5–4 years and 166 FCCH providers into a cluster-randomized control trial (intervention = 242 children/83 FCCHs, control = 254 children/83 FCCHs) conducted during 2013–2016. The 9-month intervention addressed provider health, health of the FCCH environment, and business practices, and was delivered through three workshops, three home visits, and nine phone calls. The attention control arm received a business-focused intervention. Primary outcomes were children\u27s diet quality (2 days of observed intakes summarized into Healthy Eating Index scores) and moderate to vigorous physical activity (3 days of accelerometry) at the FCCH. Secondary outcomes were child body mass index (BMI), FCCH provider health behaviors, and FCCH nutrition and physical activity environments and business practices. Repeated measures analysis, using an intent-to-treat approach, accounting for clustering of children within FCCHs and adjusting for child age, sex, and BMI, was used to evaluate change (completed in 2018). Compared to controls, intervention children significantly improved their diet quality (5.39, p = .0002, CI = 2.53, 8.26) but not MVPA (0.31, p = .195, CI = −0.16, 0.79). Intervention FCCH providers significantly improved their diet quality and several components of their FCCH environment (i.e., time provided for physical activity, use of supportive physical activity practices, and engagement in nutrition and physical activity education/professional development). FCCHs are malleable settings for health promotion, especially diet quality

Implementación del método del caso en la asignatura de Ingeniería de Procesos y Productos II del grado en Ingeniería Química

[EN] In this work, the case method has been used in the subject Process and Product Engineering II, which belongs to the fourth course of the Chemical Engineering Degree of the Universitat de València. Different cases have been proposed in the classroom practices in order to students acquire the competences of the subject and improve the results of the exam. A rubric was designed to evaluate the cases which was accessible to the students. The cases were proposed in the exam, in particular, cases related to four lessons which are usually complicated to students and the results obtained for these cases were compared with the results obtained in the questions (presented in a theoretical way) of the same topics but carried out the last two academic years in the exam. According to the results, the new methodology has been useful to improve the academic performance of students, since the case method motivates students and makes possible to know real situations which they will face in an imminent professional future. Nevertheless, the results of the exam are still very poor, and therefore, it is necessary to go on working with the case method in the future.[ES] En el presente trabajo se ha aplicado la metodología del caso para la asignatura de Ingeniería de Procesos y de Productos II de cuarto curso del Grado en Ingeniería Química de la Universitat de València. Se propusieron distintos casos en las prácticas de aula de la asignatura con el fin de que el alumnado adquiriera las competencias de la asignatura y se mejoraran los resultados del examen. Se diseñó una rúbrica para evaluar los casos que estuvo accesible para el estudiantado. Se propusieron casos prácticos a resolver en el examen de la asignatura, concretamente de cuatro temas que presentan gran dificultad al alumnado y se compararon los resultados con los obtenidos en dos cursos académicos anteriores para estas mismas preguntas pero presentadas de forma teórica. De acuerdo con los resultados obtenidos, la nueva metodología sí ha servido para mejorar el rendimiento académico, ya que el método del caso motiva al alumnado y les permite conocer situaciones reales a las cuales se va a enfrentar en un inminente futuro profesional. Sin embargo, los resultados del examen siguen siendo muy bajos, por lo que se tiene que seguir trabajando con la metodología en la asignatura.Los autores quieren agradecer al Proyecto de innovación docente concedido por el Vicerrectorado de Ocupación y Programas Formativos de la Universitat de València (UV-SFPIE_PID20-1351761).Solsona, B.; Fernández-Domene, R.; Sánchez-Tovar, R.; Sanchis, R. (2021). Implementación del método del caso en la asignatura de Ingeniería de Procesos y Productos II del grado en Ingeniería Química. En IN-RED 2021: VII Congreso de Innovación Edicativa y Docencia en Red. Editorial Universitat Politècnica de València. 128-139. https://doi.org/10.4995/INRED2021.2021.1347112813

Microtomographic reconstruction of mandibular defects treated with xenografts and collagen-based membranes:a pre-clinical minipig model

The goal of this study was to evaluate hard tissue response following guided bone regeneration using commercially available bovine bone grafts and collagen membranes; bilayer collagen membrane and porcine pericardium-based membrane, by means of a non-destructive three-dimensional (3D) computerized volumetric analysis following microtomography reconstruction. Bone regenerative properties of various bovine bone graft materials were evaluated in the Göttingen minipig model. Two standardized intraosseous defects (15mm x 8mm x 8mm) were created bilaterally of the mandible of eighteen animals (n=72 defects). Groups were nested within the same subject and randomly distributed among the sites: (i) negative control (no graft and membrane), (ii) bovine bone graft/bilayer collagen membrane (BOB) (iii) Bio-Oss® bone graft/porcine pericardium-based membrane (BOJ) and (iv) cerabone® bone graft/porcine pericardium-based membrane (CJ). Samples were harvested at 4, 8, and 12-week time points (n=6 animal/time point). Segments were scanned using computerized microtomography (?CT) and three dimensionally reconstructed utilizing volumetric reconstruction software. Statistical analyses were performed using IBM SPSS with a significance level of 5%. From a temporal perspective, tridimensional evaluation revealed gradual bone ingrowth with the presence of particulate bone grafts bridging the defect walls, and mandibular architecture preservation over time. Volumetric analysis demonstrated no significant difference between all groups at 4 weeks (p>0.127). At 8 and 12 weeks there was a higher percentage of new bone formation for control and CJ groups when compared to BOB and BOJ groups (p<0.039). The natural bovine bone graft group showed more potential for graft resorption over time relative to bovine bone graft, significantly different between 4 and 8 weeks (p<0.003). Volumetric analysis yielded a favorable mandible shape with respect to time through the beneficial balance between graft resorption/bone regenerative capacity for the natural bovine bone graft

A multiplatform experiment to unravel meso- and submesoscale processes in an intense front (AlborEx).

© The Authors, 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Pascual, A., Ruiz, S., Olita, A., Troupin, C., Claret, M., Casas, B., Mourre, B., Poulain, P. M., Tovar-Sanchez, A., Capet, A., Mason, E., Allen, J. T., Mahadevan, A., & Tintore, J. A multiplatform experiment to unravel meso- and submesoscale processes in an intense front (AlborEx). Frontiers in Marine Science, 4(39), (2017), doi:10.3389/fmars.2017.00039.The challenges associated with meso- and submesoscale variability (between 1 and 100 km) require high-resolution observations and integrated approaches. Here we describe a major oceanographic experiment designed to capture the intense but transient vertical motions in an area characterized by strong fronts. Finescale processes were studied in the eastern Alboran Sea (Western Mediterranean) about 400 km east of the Strait of Gibraltar, a relatively sparsely sampled area. In-situ systems were coordinated with satellite data and numerical simulations to provide a full description of the physical and biogeochemical variability. Hydrographic data confirmed the presence of an intense salinity front formed by the confluence of Atlantic Waters, entering from Gibraltar, with the local Mediterranean waters. The drifters coherently followed the northeastern limb of an anticyclonic gyre. Near real time data from acoustic current meter data profiler showed consistent patterns with currents of up to 1 m/s in the southern part of the sampled domain. High-resolution glider data revealed submesoscale structures with tongues of chlorophyll-a and oxygen associated with the frontal zone. Numerical results show large vertical excursions of tracers that could explain the subducted tongues and filaments captured by ocean gliders. A unique aspect of AlborEx is the combination of high-resolution synoptic measurements of vessel-based measurements, autonomous sampling, remote sensing and modeling, enabling the evaluation of the underlying mechanisms responsible for the observed distributions and biogeochemical patchiness. The main findings point to the importance of fine-scale processes enhancing the vertical exchanges between the upper ocean and the ocean interior.The AlborEx experiment was conducted in the framework of PERSEUS EU-funded project (Grant agreement no: 287600). The experiment was led by the Spanish National Research Council (CSIC) institution with strong involvement and cooperation from other national and international partners: Balearic Islands Coastal Observing and Forecasting System (SOCIB, Spain); Consiglio Nazionale delle Ricerche (CNR, Italy), McGill University (Canada); Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS, Italy) and Woods Hole Oceanographic Institution (WHOI, USA). Glider operations were partially funded by JERICO FP7 project. AP acknowledges support from the Spanish National Research Program (E-MOTION/CTM2012-31014 and PRE-SWOT/CTM2016-78607-P). SR and AP are also supported by the Copernicus Marine Environment Monitoring Service (CMEMS) MedSUB project. EM is supported by a post-doctoral grant from the Conselleria d'Educació, Cultura i Universitats del Govern de les Illes Balears (Mallorca, Spain) and the European Social Fund. AC is a FNRS researcher under the FNRS BENTHOX project (Convention T.1009.15). The altimeter products were produced by Ssalto/Duacs and distributed by CMEMS. The profiling floats and some drifters were contributed by the Argo-Italy program. The authors are in debt with A. Massanet, F. Margirier, M. Palmer, C. Castilla, P. Balaguer and for their efficient work and implication during the AlborEx cruise. We also thank M. Menna, G. Notarstefano and A. Bussani for their help with the drifter and float data processing and the production of some figures. This article was initiated during a research visit of the first two authors to Woods Hole Oceanographic Institution