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Megacities expansion around the globe have significantly increased the demand for resources to the point of depleting available reservoirs and requiring importing resources from nearby locations sometimes implementing major infrastructure projects for guaranteeing access to resources. This is particularly true for one of the largest Megalopolis in the world, Mexico City, that imports 40% of its water supply from neighboring states. Despite of being a city holding important hydric resources, the lack of strategies, technological innovation, user-centered service design, consistent data acquiring, and optimization tools have led to a poor water management that maintains the metropolis with a constant scarcity of the resource. Therefore, the aim of the current paper is to present a conceptual service design for smart rainwater harvesting in urban settlements that provides an alternative source for citizens to reduce the local hydric stress, diminish aquifer overexploitation and increase water well recovery contributing to more sustainable cities. [ABSTRACT FROM AUTHOR]

As a turn-design strategy, repeating another has been described for English as a fairly restricted way of constructing a response, which, through re-saying what another speaker just said, is exploitable for claiming epistemic primacy, and thus avoided when a second speaker has no direct experience. Conversations in Mesoamerican languages present a challenge to the generality of this claim. This paper examines the epistemics of dialogic repetition in video-recordings of conversations in three Indigenous languages of Mexico: Tzeltal and Yucatec Maya, both spoken in southeastern Mexico, and Lachixío Zapotec, spoken in Oaxaca. We develop a typology of repetition in different sequential environments. We show that while the functions of repeats in Mesoamerica overlap with the range of repeat functions described for English, there is an additional epistemic environment in the Mesoamerican routine of repeating for affirmation: a responding speaker can repeat to affirm something introduced by another speaker of which s/he has no prior knowledge. We argue that, while dialogic repetition is a universally available turn-design strategy that makes epistemics potentially relevant, cross-cultural comparison reveals that cultural preferences intervene such that, in Mesoamerican conversations, repetition co-constructs knowledge as collective process over which no individual participant has final authority or ownership. • As a turn-design strategy, repeating another makes relevant epistemic primacy. • English-language data shows repetition mediated when lacking direct experience. • Cross-cultural study of dialogic repetition in Mayan and Zapotec languages. • Responding speaker can repeat to affirm something she has no prior knowledge of. • Repetition co-constructs knowledge as collective process not owned territories. [ABSTRACT FROM AUTHOR]

• A slit damper for precast beam-column connections is proposed. • Quasi-static incremental and constant-amplitude cyclic tests were conducted. • The damper showed stable hysteretic behavior and adequate seismic performance. • Non-uniform struts increased the damper's cyclic performance in general. • Numerical modeling techniques were validated with finite element analyses. Since the 2017 Puebla-Morelos Earthquake, interest in limiting damage to structural components has exponentially increased in Mexico. Consequently, the use of energy dissipation devices has received renewed attention. Following that line, this paper studies an attractive solution, which is a slit damper proposed as a passive energy dissipation device for, but not limited to, precast beam-column connections. Slit dampers have been studied for their cost-effectiveness and ease of application. They present stable hysteretic behavior and dissipate substantial amounts of energy under cyclic loading while maintaining less ductile elements essentially elastic. The structural behavior of the proposed device was evaluated theoretically, followed by experimental verification. Quasi-static incremental and constant-amplitude cyclic tests were conducted on eight specimens, with two of them having non-uniform struts. Test results are presented and discussed, emphasizing ductility and energy dissipation capacity. The proposed damper showed stable hysteretic behavior and adequate seismic performance. Using non-uniform struts significantly increased the damper's deformation capacity and fatigue performance, which is desirable for seismic zones where long-duration earthquakes are expected, such as in Mexico City. Numerical modeling techniques were also validated with finite element analyses. It was shown that the proposed damper's hysteretic response could be accurately predicted using the combined non-linear isotropic and kinematic hardening model. [ABSTRACT FROM AUTHOR]

This paper estimates the effects of extending the school day during elementary school on students' educational outcomes later in life. The analysis takes place in the context of a large-scale program introduced in 2007 that extended the school day from 4.5 to 8 h in Mexico City's metropolitan area. The identification strategy leverages cohort-by-cohort variation in full-time enrollment in elementary schools. The results indicate that full-time elementary schools have positive and long-lasting effects on students' performance, increasing high-stakes high school admission test scores by 4.8 percent of a standard deviation. The effects are larger for females than for males. The difference in the effects between males and females of 2.1 percent of a standard deviation represents 16% of the gender gap in the high school admission exam. Moreover, full-time schooling decreases the probability of delays in schooling completion. [ABSTRACT FROM AUTHOR]

This paper shows the thermal performance of a window system with a shading cover made out of a phase change material (window-PCM shutter). The analysis was the numerical study where conjugated heat transfer was considered on the whole system window-PCM shutter. The modeling was conducted under warm (Merida) and cold weather (Toluca) conditions in México for the warmest and coldest day. Two different phase change materials (PCMs) were selected for the study: Paraffin wax - MG29 and n -octadecane. The results show that the n -octadecane and the MG29 were capable of keeping the inside comfort temperature for 14:35 and 16:23 h, respectively. The n -octadecane and MG29 reduced the energy of the window-PCM shutter inside surface by 67.3 and 71.6%, respectively, compared to a conventional window. Under cold weather conditions also occurred reductions of heat fluxes by 87.2 (n -octadecane) and 83% (MG29) with the window-PCM shutter system compared to a conventional window, causing non-comfort temperatures. The use of a window-PCM shutter is highly recommended under warm weather conditions, given that it showed to be a viable option for energy savings in buildings; however, for its implementation under cold weather conditions of México, it becomes necessary further investigations with other PCMs. [ABSTRACT FROM AUTHOR]

The planetary boundary layer (PBL) height plays a major role in air quality and weather forecast studies. However, it cannot be directly measured as it can only be determined from the measured profiles of atmospheric parameters such as., temperature, moisture, and aerosol backscatter based on different retrieval mechanisms. This paper presents the PBL features such as., stable boundary layer (SBL), convective boundary layer (CBL), and residual layer (RL) detected from the microwave radiometer (MWR), mini Micro Pulse Lidar (MPL), and radiosondes (RS) and an intercomparison was done between the instruments during the period of 16 February – 31 May 2019 in Mexico City. RS were launched thrice a day during this period at 06 LST, 12 LST, and 18 LST respectively. The PBL heights comparison was classified into 3 categories: MWR-RS, mini MPL-RS, and mini MPL-MWR. The daytime CBL heights for the MWR-RS comparison correlate well (r = 0.96 at 12 LST, r = 0.88 at 18 LST) as well as RL height (r = 0.94 at 06 LST). The CBL and RL heights for the mini MPL-RS and mini MPL-MWR comparison also agree very well (0.89 < r < 0.99). Overall, the corresponding SBL height comparisons at 06 LST yielded lower agreements (r < 0.66) with the lowest correlation values for the mini MPL-MWR comparison (r = 0.39), which is likely due to the inability of the mini MPL to detect aerosol backscatter below ~120 m above ground level (agl) as well as the stability of the atmosphere, which prevents uniform mixing of the aerosol particles. [Display omitted] • Intercomparison of microwave radiometer, micro-pulse lidar and radiosondes during 3 months. • Overall good agreement in the detection of the convective and residual boundary layer heights. • Lower agreement for the stable boundary layer height. [ABSTRACT FROM AUTHOR]

Model emulation has become an integral tool in scenario analysis, risk assessment, and calibration of environmental models. Of particular interest is dynamic emulation – the approximation of model outputs from inputs or processes that vary in time. This paper presents a method for data-driven dynamic emulation of high-dimensional model outputs that overcomes the logistical challenges from assumptions in traditional multivariate statistics concerning output covariance. In this method, outputs are subjected to principal component analysis, and Gaussian random fields are fit along new orthogonal axes to accommodate spatial heterogeneity and serial correlation. The technique is demonstrated on a regional groundwater model of metropolitan Mexico City, where it successfully emulates spatial and temporal dynamics of land subsidence and aquifer level fluctuation resulting from two management scenarios. In doing so, we introduce methodological advances to emulation techniques, which facilitate the use of models with high-dimensional outputs in computationally expensive planning and optimization applications. • Novel emulation of model outputs overcomes assumptions in traditional multivariate statistics concerning output covariance. • Maintains the same spatiotemporal detail of original model. • Case study of groundwater management and land subsidence in Mexico City. [ABSTRACT FROM AUTHOR]