scholarly journals Long-Term Efficiency of Catalytic Converters Operating in Mexico City

2001 ◽  
Vol 51 (5) ◽  
pp. 725-732 ◽  
Author(s):  
Luis Díaz ◽  
Isaac Schifter ◽  
René Rodriguez ◽  
Sergio Avalos ◽  
Gabriel López ◽  
...  
2015 ◽  
Vol 3 (11) ◽  
pp. 6651-6688
Author(s):  
J. Yu ◽  
G. Wang

Abstract. This study investigates current ground motions derived from the GPS geodesy infrastructure in the Gulf of Mexico region. The positions and velocity vectors of 161 continuous GPS (CGPS) stations are presented with respect to a newly established local reference frame, the Stable Gulf of Mexico Reference Frame (SGOMRF). Thirteen long-term (> 5 years) CGPS are used to realize the local reference frame. The root-mean-square (RMS) of the velocities of the 13 SGOMRF reference stations achieves 0.2 mm yr−1 in the horizontal and 0.3 mm yr−1 in the vertical directions. GPS observations presented in this study indicate significant land subsidence in the coastal area of southeastern Louisiana, the greater Houston metropolitan area, and two cities in Mexico (Aguascalientes and Mexico City). The most rapid subsidence is recorded at the Mexico City International airport, which is up to 26.6 cm yr−1 (2008–2014). Significant spatial variation of subsidence rates is observed in both Mexico City and the Houston area. The overall subsidence rate in the Houston area is decreasing. GPS observations in southeastern Louisiana indicate minor (4.0–6.0 mm yr−1) but consistent subsidence over time and space. This poses a potential threat to the safety of costal infrastructure in the long-term.


Author(s):  
DIANE E. DAVIS

What constitutes modern Mexico? Is there a clear distinction between the historic and modern Mexico City? And if there are, does this distinctions hold up throughout the twentieth century, when what is apparent is a mix of legacies coexisting overtime? This chapter discusses the semiotics of history and modernity. It discusses the struggle of the Mexico City to find its own image including its struggle to preserve historic buildings amidst the differing political alliances that either promote change or preserve the past. However, past is not a single entity, hence if the preservation of the rich history of Mexico is pursued, the question arises as to what periods of history represented in the city are to be favoured in its future development. In this chapter, the focus is on the paradoxes of the Torre Bicentenario and on the pressures to preserve Mexico’s past, the ways they have been juxtaposed against the plans for its future and how the balance of these views has shifted over time. It determines the key actors and the institutions who have embraced history as opposed to progress, identifies the set of forces that dominated in the city’s twentieth-century history, and assesses the long-term implications of the shifting balance for the social, spatial and built environmental character of the city. The chapter ends with a discussion on the current role played by the cultural and historical authorities in determining the fate of the city.


2016 ◽  
Vol 16 (7) ◽  
pp. 1583-1602 ◽  
Author(s):  
Jiangbo Yu ◽  
Guoquan Wang

Abstract. This study investigates current ground deformation derived from the GPS geodesy infrastructure in the Gulf of Mexico region. The positions and velocity vectors of 161 continuous GPS (CGPS) stations are presented with respect to a newly established local reference frame, the Stable Gulf of Mexico Reference Frame (SGOMRF). Thirteen long-term (> 5 years) CGPS are used to realize the local reference frame. The root mean square (RMS) of the velocities of the 13 SGOMRF reference stations achieves 0.2 mm yr−1 in the horizontal and 0.3 mm yr−1 in the vertical directions. GPS observations presented in this study indicate significant land subsidence in the coastal area of southeastern Louisiana, the greater Houston metropolitan area, and two cities in Mexico (Aguascalientes and Mexico City). The most rapid subsidence is recorded at the Mexico City International airport, which is up to 26.6 cm yr−1 (2008–2014). Significant spatial variation of subsidence rates is observed in both Mexico City and the Houston area. The overall subsidence rate in the Houston area is decreasing. The subsidence rate in southeastern Louisiana is relatively smaller (4.0–6.0 mm yr−1) but tends to be steady over time. This poses a potential threat to the safety of coastal infrastructure in the long-term.


Author(s):  
Rosa-Elena Ulloa ◽  
Emmanuel Sarmiento

ABSTRACT Objective: The aim of this study is to determine the demographic and clinical characteristics associated with the need for long-term treatment in a child psychiatry facility. Method: Demographic characteristics, diagnosis, source of referral, time elapsed between the earthquake and the request for care, and the treatment prescribed in the baseline assessment were compared between a group of subjects that required long-term treatment (LTT) and a group that was discharged after a brief intervention (D). Results: A total of 171 patients were seen, and 27% of the subjects required LTT. In general, these subjects were younger, referred from highly affected areas, presented a delay in seeking care, and were mainly diagnosed with anxiety and stress-related disorders. Conclusions: These findings suggest the need for research regarding the design of mental health programs for the early detection of psychopathology after natural disasters in children and adolescents.


2007 ◽  
Vol 176 (4) ◽  
pp. 377-384 ◽  
Author(s):  
Rosalba Rojas-Martinez ◽  
Rogelio Perez-Padilla ◽  
Gustavo Olaiz-Fernandez ◽  
Laura Mendoza-Alvarado ◽  
Hortensia Moreno-Macias ◽  
...  

Subject Implications of the USMCA. Significance Mexico’s Senate on December 12 ratified changes to the US-Mexico-Canada Agreement on free trade (USMCA), agreed on December 10. Several important changes were signed by the three governments in Mexico City, altering the original agreement signed in November 2018. Mexico now awaits ratification of the final deal in Washington and Ottawa. If enacted, the accord will replace NAFTA, which has determined the rules of trade among the countries since 1994. Impacts What was initially framed as a political victory for AMLO may lose lustre as details emerge on the concessions granted by his government. Long-term auto industry investments in Mexico may suffer due to new stipulations on issues such as regional content and wages. After the USMCA is formally enacted, Trump will probably focus on seeking to reduce the US trade deficit with China.


1999 ◽  
Vol 35 (11) ◽  
pp. 3327-3341 ◽  
Author(s):  
Adrian Ortega-Guerrero ◽  
David L. Rudolph ◽  
John A. Cherry

Author(s):  
Rosa María Wong-Chew ◽  
Edwin Xchel Rodríguez Cabrera ◽  
Carlos Alberto Rodríguez Valdez ◽  
Julieta Lomelín Gascon ◽  
Linda Morales Juárez ◽  
...  

Recently, several reports have emerged describing the long-term consequences of COVID-19 that may affect multiple systems, suggesting its chronicity. As further research is needed, we conducted a longitudinal observational study to report the prevalence and associated risk factors of long-term health consequences of COVID-19 by symptom clusters in patients discharged from the Temporary COVID-19 Hospital (TCH) in Mexico City. Self-reported clinical symptom data were collected via telephone calls over 90 days post-discharge. Among 4670 patients discharged from the TCH, we identified 45 symptoms across eight symptom clusters (neurological; mood disorders; systemic; respiratory; musculoskeletal; ear, nose, and throat; dermatological; and gastrointestinal). We observed that the neurological, dermatological, and mood disorder symptom clusters persisted in >30% of patients at 90 days post-discharge. Although most symptoms decreased in frequency between day 30 and 90, alopecia and the dermatological symptom cluster significantly increased (p<0·00001). Women were more prone than men to develop long-term symptoms and invasive mechanical ventilation also increased the frequency of symptoms at 30-days post-discharge. Overall, we observed that symptoms often persisted regardless of disease severity. We hope these findings will help promote public health strategies that ensure equity in the access to solutions focused on the long-term consequences of COVID-19.


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