Mexico City Research Articles

Strategic Dimensions of Eco-Innovation Adoption in Manufacturing SMEs in the Context of Mexico City

This paper investigates the strategic dimensions influencing the adoption of environmental innovations (EIs) in small and medium-sized manufacturing enterprises (SMEs) in Mexico City. The study aims to understand the fundamental strategic dimensions defining eco-innovation and examine how SMEs manage the complexities of incorporating these practices. Employing a mixed-methods approach with documentary analysis and expert interviews, the study identifies key factors influencing EI adoption through causal maps and the viable system model. Findings highlight the significance of external and internal factors such as competitive pressure, economic constraints, technological capabilities, political support, and social influence. This integrative approach emphasizes the importance of adaptability and responsiveness, presenting eco-innovation as a source of sustainable competitive advantage for SMEs.

Prognostic Factors of Survival in Patients With Gastric Cancer Under 45 Years Old Treated With Surgery in a Single Center in Mexico City.

Introduction Gastric cancer is a significant major global health concern, particularly prevalent in Asia. In recent years, a large number of new cases have been diagnosed worldwide, leading to a substantial number of deaths. The disease tends to present more aggressively in these cases, leading to debates about the prognosis and survival outcomes. Nonetheless, research has shown that survival rates improve significantly when the tumor is completely surgically resected. Materials and methods This retrospective study included patients between 16 and 45 years old, diagnosed with gastric cancer, with the support of the pathology department, who underwent surgery in the upper GI service, in the period from January 2006 to December 2012.Data collected encompassed variables such as gender, age, tumor size, type of surgery, overall survival, disease-free period, type and histological degree of the tumor, clinical stage of the cancer, and R0 resection (curative resection). All patients with a confirmed diagnosis of gastric cancer were included and treated with surgery and D1 limited dissection or extended D2 dissection. Patients who have received chemotherapy prior to surgical treatment and those who have been surgically treated outside the XXI Century National Medical Center were excluded. Results A total of 104 patients were included; the predominant histological type was diffuse adenocarcinoma accounting for 79.8% and 81.7% of the cases were histologicalgrade 3. The most common clinical stage was IIIA in 41.3% of the cases. In 53.8% of the cases, we obtained an R0 resection. D2 lymphadenectomy was performed in 53.8% of the cases, with an overall survival rate of 82.69%. Significant prognostic factors for survival included T4 depth with an increase in risk for mortality (OR: 25.93; 95% CI: 6.41-53.54; p=0.001), lymph node status (OR: 14.76; 95% CI: 4.6-46.83; p<0.001), and size greater than 5 cm (OR: 1.8; 95% CI: 0.61-6.35; p<0.001). Conclusions Gastric cancer is more common in adults aged above 60 years old, but the incidence in young adults under 45 years old has been increasing. Although young gastric cancer patients present with more aggressive tumor behavior, these patients can have similar or even better overall survival compared to older patients, being 35% in some cases, especially in the resectable setting. Further research is still needed to fully characterize the unique biology and optimal management of gastric cancer in young adults.

Genital ulcers in hospitalized patients: How often is genital herpes the culprit?

AbstractBackgroundGenital herpes (GH) is the main infectious cause of genital ulcers worldwide. Clinical diagnosis alone may be misleading, especially in immunocompromised patients in whom atypical presentations are common.ObjectivesTo assess the herpetic etiology of genital ulcers in immunocompromised and immunocompetent hospitalized adults, and to identify the most frequent differential diagnoses within each patient group.MethodsWe conducted a retrospective transverse study at a third‐level center in Mexico City using PCR testing (HSV‐1, HSV‐2, VZV) in hospitalized patients with genital ulcers to diagnose GH. When negative, biopsy and tissue cultures were taken to establish the final diagnosis. Data from a 2‐year period (March 2021 to April 2023), including demographic characteristics, comorbidities, initial clinical suspicion, PCR test results, skin tissue biopsy results, cultures results, and final diagnosis, were collected from May 2023 to June 2023.ResultsA total of 59 hospital patients with genital ulcers underwent PCR testing due to clinical suspicion of GH, of which 39 (66%) were immunocompromised. The diagnosis was confirmed in 32/59 cases (54%), of which 22/32 (69%) were immunocompromised and 10/32 (31%) immunocompetent. In the 17 immunocompromised adults in whom GH was excluded, other viral (34%) or bacterial (23%) infections were the next most frequent etiologies. Meanwhile, among the 10 immunocompetent patients without GH, noninfectious causes, such as incontinence‐associated dermatitis (15%) and trauma or pressure ulcers (15%), were the most prevalent.ConclusionsGenital ulcers in hospitalized adults should raise the suspicion of infectious etiologies, particularly of GH. Diagnostic confirmation with tests such as PCR is crucial given the uncertainty of its clinical diagnosis. Once GH diagnosis is excluded, immunocompromised patients should be evaluated for other infectious etiologies, while noninfectious causes should be considered first in immunocompetent patients.

Effectiveness of ICS/LABA and LAMA/LABA in COPD due to biomass.

COPD due to biomass exposure (COPD-B) is highly prevalent in low- and middle-income countries, and there are no clinical trials designed to evaluate the effectiveness of the treatments currently recommended for patients with COPD due to cigarette smoking (COPD-C). The purpose of the study was to compare the efficacy of fluticasone furoate/vilanterol (FF/V) 100/25 μg and umeclidinium/vilanterol (UMEC/VI) 62.5/25 μg on the rate of exacerbations, the time to first exacerbation, on dyspnoea, health-related quality of life (HRQL), forced expiratory volume in 1 s (FEV1) and inspiratory capacity (IC) during a period of 6 months in patients with COPD-B and COPD-C, at a third level referral centre in Mexico City. A pilot, single-centre, open-label, parallel-group study included 132 patients with a history of at least two exacerbations. They were randomised to receive one of four treatment groups: 33 COPD-B patients received FF/VI 100/25 μg, 31 COPD-B patients received UMEC/VI 62.5/25 μg, 34 COPD-C patients received FF/V and 34 COPD-C patients received UMEC/VI. There were no differences in exacerbation rates between patients receiving FF/VI or UMEC/VI in either the COPD-B (0.07 (95% CI 0.03-0.13), 0.06 (95% CI 0.03-0.12)) or COPD-C group (0.06 (95% CI 0.04-0.11), 0.08 (95% CI 0.05-0.13)), nor in the time of first exacerbation, nor FEV1 and IC. All groups showed improvement in dyspnoea and HRQL, independently of medication used. Among patients with COPD-B and COPD-C with a history of exacerbation, FF/VI was equally effective as UMEC/VI in preventing exacerbations and improving dyspnoea and HRQL.

O-197 Correlation of intracellular pH of non-normozoospermic men with fertilization rates in assisted reproduction procedures (Pilot study)

Abstract Study question Does measuring qualitative changes in the sperm pHi could predict the fertilizing potential of a non-normozoospermic patients under fertility treatment? Summary answer The increase of pHi correlates with fertilization rates. What is known already The intracellular pHi (pHi) is of great importance for a wide variety of sperm physiological processes, including its motility. The pHi regulates several key sperm proteins, such as the Ca2+ channel, CatSper (sperm cation channel) which is involved in sperm hyperactivation and the K+ channel SLO3.The latter participates in the regulation of membrane potential during capacitation. Interestingly, human sperm pHi has been found to positively correlate with both hyperactivated motility and in vitro fertilization (IVF) success in normozoospermic patients. Study design, size, duration This prospective study employed unidentified semen samples from 62 non-normozoospermic men (patients, age 38 ± 4 years old) undergoing fertility treatment from January to November 2023 at CITMER Reproductive Medicine, Mexico City. Frozen semen samples and procedures with less than 4 oocytes were excluded. The pHi of sperm samples was evaluated by time-lapse flow cytometry. For comparison, the pHi of 13 normozoospermic men (donors, age 28 + 6 years old) were also analyzed. Participants/materials, setting, methods Sperm were separated by density gradient and incubated in capacitating HTF media to be used for conventional IVF or ICSI. Cells were stained with vitality (propidium iodide) and pHi (BCECF-AM) sensitive fluorescent dyes. Fluorescence changes were evaluated using an AccuriC6 flow cytometer. For each pHi recording, 10 mM NH4Cl were used as an alkalinization positive control and for data normalization. Basal levels of sperm pHi and its correlation with fertilization rates, were performed using R. Main results and the role of chance The changes in pHi were recorded as changes in the BCECF fluorescence. The increase in fluorescence is proportional to an increase in pHi and vice versa. Interestingly, we observed that the increase in pHi in sperm used for ICSI but not for IVF procedures, which were paired with oocytes from female donors, are positively and significantly correlated with higher fertilization rates (R = 0.68; *p=0.02). This seems to be the same for ICSI treatment pairing sperm with oocyte from the female partner, although the correlation is not yet statistically significant (R = 0.44; p = 0.12). We did not find significant differences in the basal pHi values between sperm from donors and patients; however, we observed that sperm from patients, had higher pHi values (0.57 + 0.15 a.u.f) compared to sperm from donors (0.48 + 0.24 a.u.f). Our results suggest that sperm pHi may be an important regulator for the process of fusion and not only for fertilization. Qualitative sperm pHi values can contribute to predicting fertilization success in patients undergoing ICSI treatment. Limitations, reasons for caution The preliminary nature of the results implies a necessity to increase the number of analyzed semen samples. Physiological responses may vary even among the same patient or cell’s donor. Our population-based analysis could be underestimating such single cell variations. Wider implications of the findings Current protocols for sperm analysis fail to successfully predict the fertilizing capacity of semen samplest.Measuring pHi in capacitated sperm, could be a promising tool to help clinicians choose the best fertilization technique for each couple. This protocol is easy to perform in a laboratory that has a flow cytometer. Trial registration number Not applicable

Hallazgo de Pleurotus cystidiosus (Agaricales, Pleurotaceae) en el norte de México

Background and Aims: Some species of Pleurotus form anamorphs that produce coremia and arthrospores, which are classified in the subgenus Coremiopleurotus and are morphologically very similar. In Mexico, seven species of the genus are known; however, only P. smithii, described from Mexico City, is known to form coremia. Recent collections of Pleurotus from Chihuahua, Mexico, showed distinct characteristics from the known species for the country, whose morphological and molecular characterization allowed us to identify P. cystidiosus in Mexico. The objective of this work was to document the presence of P. cystidiosus in Mexico and provide a detailed description of the specimens found in the country. Methods: The material was collected in Ciudad Juárez, Chihuahua, Mexico. Specimens were characterized macro- and microscopically through in situ photographs, polyfocal, and light microscopy. Morphological identification was performed using specialized literature. DNA extraction was carried out following a 3% CTAB protocol. The ITS region was amplified using the primer pairs ITS5/ITS4. Phylogenetic analyses were conducted using Maximum Likelihood and Bayesian Inference. Key results: Pleurotus cystidiosus, a species previously unreported in Mexico, is morphologically and taxonomically described, confirmed with barcode sequences. The species is distinguished by the presence of abundant clavate to pyriform pleurocystidia and subglobose cheilocystidia in the teleomorph, as well as the formation of coremia with a white stipe, black head, and segments of arthrospores up to 17-25 × 5-7.5 µm in the anamorph. Conclusions: The presence of P. cystidiosus in the north of Mexico is confirmed. With this study, the number of known Pleurotus species for Mexico increases to eight.

Street vendors as actors of a sustainable food system—The case of Mexico City

AbstractIn this paper, we explore the role of street vendors in enhancing access to sustainable food, using Mexico City as a case study. Through observational fieldwork, we quantify and spatialize the street food offer of two municipalities, which we compare to food offer in outlets (shops and restaurants). We use Mexican traditional food as a proxy for a sustainable diet. Street vendors represent 55% of the food retailers present in the study area. Over half of street vendors only sell traditional food (against 45% of food outlets), but most sell food to be consumed in moderation (e.g. tacos). A weak statistical correlation suggests that street vendors and food outlets tend to cluster in mixed‐use areas; as such, street vendors' role in the urban food system is mainly to provide an alternative food offer in well‐served areas, rather than providing a food offer in neighbourhoods where the formal offer is scarce. We conclude that street vending is a significant element of Mexico City's urban food environment and increases the availability of traditional food, thus enhancing food sovereignty and contributing to a sustainable food system. Street vending, as an unplanned, traditional daily practice that inadvertently contributes to a sustainable food system, is an example of ‘already existing sustainabilities’, which exploration can provide crucial insights to achieve sustainability transitions.

Screening Will Always Be Essential. Providers and Staff Discuss the Implementation of Anal Cancer Screening for Persons Living With HIV in Mexico City

Screening Will Always Be Essential. Providers and Staff Discuss the Implementation of Anal Cancer Screening for Persons Living With HIV in Mexico City

Neoadjuvant Imatinib in Gastrointestinal Stromal Tumors (GIST): The First Analysis of a Mexican Population.

Introduction Gastrointestinal stromal tumors (GISTs) are neoplasms originating from the interstitial cells of Cajal, pacemaker cells responsible for intestinal motility. Patients with locally advanced GISTs and those with borderline resections due to the proximity of vital anatomical structures, which could result in unacceptable post-surgical morbidity, require special therapeutic consideration. Imatinib, a tyrosine kinase inhibitor, has demonstrated significant successin the non-surgical management of metastatic GIST, and its favorable impact on overall survival in the adjuvant setting makes it logical to speculate on the benefit it could provide as a neoadjuvant medication in patients with locally advanced disease. Methods Patients aged 18-90 years with a diagnosis of GIST confirmed by immunohistochemistry (CD117 positivity) who were treated at the Oncology Hospital of Centro Médico Nacional Siglo XXI in Mexico City from January 2012 to December 2016 were included in the study. It is a retrospective study with a duration of four years. Clinical data were collected from the medical records, which included sex, age, tumor location, initial resectability, reason for unresectability, initial tumor size, and mitotic rate. In the case of unresectable disease, patients who were evaluated by medical oncology and who had received treatment with 400 mg of imatinib daily were evaluated. Results A total of 312 patients diagnosed with GIST were analyzed. One hundred thirty-one were men (42%) with a mean age of 57 years, and 181 were women (58%) with a mean age of 59 years. The most frequent anatomical location was the stomach (n=185, 59.2%). At the time of diagnosis, 210 patients (67.3%) presented with resectable disease, while n=102 patients (32.7%) had unresectable disease. A total of 102 patients with unresectable disease received therapy with 400 mg of imatinib per day. Sixteen patients (15.7%) presented a reduction in tumor dimensions and underwent surgery. Conclusion The study highlights the importance of complete surgical resection and the potential benefit of neoadjuvant imatinib therapy in converting unresectable to resectable disease. The results suggest that imatinib can be effective in converting unresectable GISTs to resectable ones, allowing for a complete resection to be performed and obtaining an R0 resection in 93.7% of these cases.

I Dream of Prison

This is an autoethnographic exploration of some of my experiences in prisons in both Mexico City and England. My writing is a way for me to try to understand my journey in the light of my research as a feminist criminologist, a tool for me to begin to comprehend my journey, deconstruct my trauma, and outline how I overcame my incarceration-based trauma (IBT). The essay shines a light on how women who have been imprisoned, long after their release, continue to carry the echoes of prison as trauma responses. Autoethnography is a means to explore and contextualize my experiences in a manner that makes them relevant and meaningful to the wider social fabric, as above, so below.

Prenatal and Early Childhood Lifestyle Factors Associated With Liver Injury Biomarkers in School-Aged Children From the PROGRESS Cohort in Mexico City

Prenatal and Early Childhood Lifestyle Factors Associated With Liver Injury Biomarkers in School-Aged Children From the PROGRESS Cohort in Mexico City

Analysis of the thermal control system for the 3U CubeSat nanosatellite – “IXAYA”

Abstract In recent years, space exploration has become increasingly accessible to a diverse array of countries, facilitated in part by CubeSat nanosatellites. These versatile nanosatellites find applications in a wide spectrum of fields, from forest fire detection and meteorological observation to communication systems, particle analysis, and hot spot identification. This article delves into the outcomes of a comprehensive thermal analysis conducted on the IXAYA nanosatellite. The primary mission of this nanosatellite is to identify hot spots in the vicinity of Mexico City. The thermal analysis process entails a meticulous review of each subsystem along with the associated boundary conditions. This study commences with the definition of an optical payload and a thorough assessment of subsystem requirements. Subsequently, we calculate both external and internal thermal loads. With these foundational data points, we progress to ascertain the temperature distribution across the entirety of the satellite, ensuring that all constituent elements remain within their designated operational temperature ranges. In the closing section, we present our findings and conclusions.

International Conference on AeroSpace Science and Technology (ICASST) 2023

1. Introduction Welcome to the publication of the Proceedings of the International Conference on Aerospace Science and Technology (ICASST) 2023, which was hosted at the facilities of Centro de Desarrollo Aeroespacial (CDA), Instituto Politécnico Nacional (IPN), in the historical centre of Mexico City, Mexico, from November 19th to November 24th, 2023. ICASST 2023 was a scientific forum for the dissemination of basic research and/or technological development projects, which allows interaction between professionals, scholars and industrialists, promoting scientific-technological collaborations in the aerospace field and related areas. The program included presentations, round tables, courses/workshops as well as keynote lectures given by widely recognized national and international experts in their area. The Conference was held in a hybrid way, face-to-face/virtual.

Estimation of photovoltaic production using Spline fitting and TSCI

This study presents an alternative methodology for analyzing the difference in daily solar energy generation between two grid-connected photovoltaic arrays (PVAs) that are identical in capacity, technical characteristics, and have the same energy production measurement interval but are in two different municipalities of Mexico City (CDMX). Unlike conventional approaches, which often rely on environmental variables, this work proposes combining the cubic smoothing Spline technique with the separation of trend, seasonality, and cyclicality (TSCI) effects. The first technique reduces random variations in measurement, while the second separates the effects commonly found in time series data. The results obtained are useful for installers of this technology, as they allow them to determine in which borough a greater photovoltaic capacity is needed.

Associations between Sleep and Physical Activity Behavior Clusters and Epigenetic Age Acceleration in Mexican Adolescents.

Epigenetic aging, a marker of biological aging measured by DNA methylation, may be affected by behaviors, including sleep and physical activity. However, investigations of physical activity and sleep with epigenetic aging among pediatric populations are scant and have not accounted for correlated behaviors. The study population included 472 Mexico City adolescents (52% female). Blood collection and 7-d wrist actigraphy (Actigraph GTX-BT) occurred during a follow-up visit when participants were 14.5 (2.09) yr. Leukocyte DNA methylation was measured with the Infinium MethylationEPIC array after bisulfite conversion, and nine epigenetic clocks were calculated. Sleep versus wake time was identified through a pruned dynamic programing algorithm, and physical activity was processed with Chandler cutoffs. Kmeans clustering was used to select actigraphy-assessed physical activity and sleep behavior clusters. Linear regression analyses were used to evaluate adjusted associations between the clusters and epigenetic aging. There were three unique clusters: "Short sleep/high sedentary behavior," "Adequate sleep duration and late sleep timing/low moderate or vigorous physical activity (MVPA)," and "Adequate sleep duration/high MVPA." Compared with the "Adequate duration/high MVPA," adolescents with "Adequate duration and late sleep timing/low MVPA" had more accelerated aging for the GrimAge clock ( β = 0.63; 95% confidence interval, 0.07-1.19). In pubertal-stratified analyses, more mature adolescents in the "Adequate sleep duration and late sleep timing/low MVPA group" had accelerated epigenetic aging. In contrast, females in the "Short sleep/high sedentary" group had decelerated epigenetic aging for the Wu pediatric clock. Associations between behavior clusters and epigenetic aging varied by pubertal status and sex. Contrary results in the Wu clock suggest the need for future research on pediatric-specific clocks.

Exploring the potential for household refrigerator replacement in Mexico City

Many studies have focused on improving the energy performance of household refrigerators and finding out their performance under different operating conditions. However, there seems to be a gap regarding the potential for electrical energy savings due to retrofitting household refrigerators. This study focuses on the replacement potential of household refrigerators eight or more years old in poor households in Mexico City. The study uses a stratified sampling methodology. The results show that it is advisable to replace 77.75% of the household refrigerators that are in operation in poor households in Mexico City. The replacement of household refrigerators with energy-efficient equipment represents 36% of the electrical energy consumption for food refrigeration in the domestic sector in Mexico City.

Disconnected and Online: Privileged Lives of the Transnational Migrants in Mexico City

As global mobility surges, Mexico City has emerged as a favored destination for remote-working professionals due to its unique fusion of cultural allure and economic convenience. This paper explores the interplay between macroeconomic trends and quests for self-actualization among lifestyle migrants, informed by interviews and other fieldwork conducted in Mexico City in early 2023. It unravels the complex interplay of factors shaping attitudes, behaviors, and collective identity among these lifestyle migrants and how their conscious embeddedness dissolves as geographic arbitrage imbues them with new privileges. KEYWORDS: Digital Nomads; Lifestyle Migrants; Transnational Migration; Mexico City; Socio-Spatial Exclusion; Gentrification; Privilege; Embeddedness

A study on the /r/ assibilation in the Mexico City and Tupe Spanish

A study on the /r/ assibilation in the Mexico City and Tupe Spanish

Evaluation of the Efficiency of the Sudden Implementation of the Synchronous Online Course: Findings of a Mixed Method Study

Tragedies are neither sought nor requested. Unfortunately, they happen and affect all areas of life, especially education. However, they leave lessons that work to face new challenges. This study aims to analyze the transition from classroom classes to distance classes due to an earthquake that hit Mexico City in 2017, damaging its buildings and infrastructure, to find the necessary aspects for an efficient transition in these cases. Faculty members were interviewed about their views during the transition. The student’s grades were also compared. Student responses were analyzed in the teacher satisfaction surveys. According to the results, a statistical model was finally generated to establish a correlation between the studied factors. A model was obtained with four clusters in which different teacher profiles are grouped. Young teachers with excellent technology management or experienced teachers with good use of technology and who are very well trained is the profile required for an efficient transition. This study served as a basis to meet the contingencies, which allowed the establishment of a more expeditious and efficient online educational system.

Statistical Interdependence between Daily Precipitation and Extreme Daily Temperature in Regions of Mexico and Colombia.

We study the statistical interdependence between daily precipitation and daily extreme temperature for regions of Mexico (14 climatic stations, period 1960-2020) and Colombia (7 climatic stations, period 1973-2020) using linear (cross-correlation and coherence) and nonlinear (global phase synchronization index, mutual information, and cross-sample entropy) synchronization metrics. The information shared between these variables is relevant and exhibits changes when comparing regions with different climatic conditions. We show that precipitation and temperature records from La Mojana are characterized by high persistence, while data from Mexico City exhibit lower persistence (less memory). We find that the information exchange and the level of coupling between the precipitation and temperature are higher for the case of the La Mojana region (Colombia) compared to Mexico City (Mexico), revealing that regions where seasonal changes are almost null and with low temperature gradients (less local variability) tend to display higher synchrony compared to regions where seasonal changes are very pronounced. The interdependence characterization between precipitation and temperature represents a robust option to characterize and analyze the collective dynamics of the system, applicable in climate change studies, as well as in changes not easily identifiable in future scenarios.