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1.

Government expenditure on health and maternal mortality in México: A spatial-econometric analysis.

Pérez-Pérez, Eduardo; Serván-Mori, Edson; Nigenda, Gustavo; Ávila-Burgos, Leticia; Mayer-Foulkes, David
| Idioma(s):
OBJECTIVE: To assess the relationship between government expenditure on maternal health (GE) and maternal mortality (MM) in Mexican poor population between 2000 and 2015 in the 2457 Mexican municipalities. METHODS: Using administrative data, we performed the analysis in three stages: First, we tested the presence of selection bias in MM. Next, we assessed the presence of spatial dependence in the incidence and severity of MM. Finally, we estimated a spatial error model considering the correction of estimates for the spatial dependence and selection bias assessed before. RESULTS: MM and GE were not randomly distributed throughout the Mexican territory; the most socially vulnerable municipalities exhibited the highest levels of MM severity but the lowest levels of GE and available human and physical resources for maternal health; the incidence of MM was independent of GE; elasticity of GE-severity in MM was -4% (P < 0.01). CONCLUSIONS: Resource allocation for maternal health must move towards a more comprehensive vision, and efforts to achieve an effective delivery of universal health services must improve, particularly regarding the most vulnerable municipalities.
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2.

Mercury and other trace metals in lettuce (Lactuca sativa) grown with two low-salinity shrimp effluents: Accumulation and human health risk assessment.

León-Cañedo, Jesús A; Alarcón-Silvas, Suammy G; Fierro-Sañudo, Juan F; Rodríguez-Montes de Oca, Gustavo A; Partida-Ruvalcaba, Leopoldo; Díaz-Valdés, Tomás; Páez-Osuna, Federico
| Idioma(s): Inglés
Shrimp farming effluents from two sources of low-salinity water, well water (WW) and diluted seawater (DSW) (salinity, 1.7 g L ; electrical conductivity, 2.7 dS m ), were used to grow lettuce (L. sativa) in order to assimilate the nutrients present in shrimp effluents and produce edible biomass. The two treatments, WW and DSW, were tested in triplicate. Additionally, one hydroponic system in triplicate was constructed to grow lettuce using a nutritive solution as the control treatment (HS). The production variables of lettuce in the two crop varieties (Parris Island (VPI) and Tropicana M1 (VTM1)) showed a general trend of DSW > HS > WW with regards to the size, weight and total foliage, except for the number of leaves, which was higher with HS treatment than with WW and DSW treatments. The accumulation of Cu, Hg, Mn and Zn in edible lettuce tissue and the health risk by the intake of lettuce were evaluated. Heavy metal concentrations in edible lettuce tissue for the three treatments showed the same trend of Mn > Zn > Cu > Hg, with concentration ranges of 47.1 to 188.7, 35.7 to 66.2, 4.1 to 6.4, and 0.01 to 0.02 mg kg (dry weight), respectively. Such concentrations did not exceed the safe limits (CAC, 1984). The health risk index and target hazard quotient were <1, which indicates that the population exposed to these metals due to intake from lettuce consumption is unlikely to have adverse health effects when shrimp farming effluents are used to grow lettuce plants.
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3.

Variability of defensin genes from a Mexican endemic Triatominae: (Hemiptera: Reduviidae).

Díaz-Garrido, Paulina; Sepúlveda-Robles, Omar; Martínez-Martínez, Ignacio; Espinoza, Bertha
| Idioma(s): Inglés
Chagas disease remains a serious health problem for countries where the most common mode of transmission is infection contracted from the feces of a Triatominae insect vector. In México, 32 species of Triatoma have been identified; amongst them, is an endemic species reported to have high percentages of infection with Defensins, cysteine-rich cationic peptides, are a family of antimicrobial peptides (AMPs); the synthesis of these molecules is crucial for insect's immune defense. In the present study, the genes encoding defensins in were sequenced with the purpose of identifying the variability of these genes in a Mexican vector of We found 12 different genes encoding three mature peptides, all of which had the typical folding of a functional insect defensin. In this work two Defensins type 1 and one type 4 were identified. The pro-peptide domain was highly variable and the mature peptide was not. This is the first report focus on variability of defensins from an epidemiologically important in Mexico.
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4.

Aplicación de un programa preventivo de salud bucal en escuelas primarias mexicanas/ Application of an oral health prevention program in Mexican elementary schools

Cruz Martínez, Rosa María; Saucedo Campos, Gerardo Alfonso; Ponce Rosas, Efrén Raúl; González Pedraza Avilés, Alberto
| Idioma(s): Español
Introducción: la alta prevalencia de enfermedades bucales en los escolares, tiene un impacto importante en su salud, lo que ha generado la necesidad de desarrollar programas y estrategias a nivel de políticas públicas para su control. Objetivo: evaluar el Programa de Salud Bucal en alumnos de escuelas primarias mexicanas. Métodos: estudio de intervención comunitaria en dos escuelas primarias públicas de la Secretaria de Salud, en la Delegación de Tlalpan, Ciudad de México. Se incluyeron 111 alumnos de quinto grado de primaria, 53 pertenecientes a la escuela primaria pública del turno matutino Río Pánuco como grupo de intervención con aplicación del Programa de Salud Bucal (grupo de trabajo), y 58 correspondientes a la escuela Ignacio Rodríguez Galván, sin intervensión (grupo control). A todos los alumnos se les realizó determinación de los índices de dientes cariados, perdidos y obturados temporales, y permanentes, y el índice periodontal comunitario. Para el análisis estadístico inferencial se utilizó U de Mann-Whitney y chi cuadrado de Pearson, con nivel de significancia 0,05. Se empleó el programa estadístico SPSS versión 22. Resultados: el promedio de edad de los niños de la escuela con intervención fue de 10,9 y de la escuela control de 10,8. En el índice para dentición temporal, el promedio de dientes cariados fue de 0,49 (IC 95 por ciento 0,07-0,91) para la escuela que intervino en el programa, y de 1,10 (IC 95 por ciento 0,70-1,51) para escuela sin intervención, con diferencias estadísticas significativas (p= 0,003). En el índice periodontal comunitario, se obtuvo 92,4 por ciento de escolares sanos para la escuela que intervino en el programa, y de 70,68 por ciento para la escuela sin intervención, con diferencia estadística significativa (p= 0,003). Conclusiones: los resultados muestran que el programa es efectivo ya que la población intervenida presenta mejores condiciones de salud bucal que los escolares del grupo control, diferencia esta clínicamente relevante(AU) Introduction: the high prevalence of oral disease among school children has a great impact on their health, hence the need to develop control programs and strategies at public policy level. Objective: evaluate the Oral Health Program for Mexican elementary school children. Methods: a community intervention study was conducted in two public elementary schools from the Ministry of Health in the borough of Tlalpan, Mexico City. The study sample was composed of 111 fifth grade students, 53 from Río Pánuco morning session public school as intervention group with application of the oral health program (work group), and 58 from Ignacio Rodríguez Galván school, without intervention (control group). All students were examined to determine the rate of decay, loss, temporary fillings and permanent teeth, and the community periodontal index. Inferential statistical analysis was based on Mann-Whitney U and Pearson's chi-square, with a significance level of 0.05. Data were processed with the statistical software SPSS version 22. Results: mean age was 10.9 at the intervention school and 10.8 at the control school. With respect to the primary dentition index, the average of decayed teeth was 0.49 (CI 95 percent 0.07-0.91) for the school with the intervention program, and 1.10 (CI 95 percent 0.70-1.51) for the school without intervention, with significant statistical differences (p= 0.003). As to the community periodontal index, 92.4 percent of the children were healthy at the school with the intervention program, and 70.68 percent were healthy at the school without intervention, with a significant statistical difference (p= 0.003). Conclusions: results show that the program is effective, since the school children intervened are in better oral health conditions than those in the control group, and the difference is clinically relevant(AU)
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5.

NO instrument intercomparison for laboratory biomass burning source studies and urban ambient measurements in Albuquerque, New Mexico.

Allen, Caroline; Carrico, Christian M; Gomez, Samantha L; Andersen, Peter C; Turnipseed, Andrew A; Williford, Craig J; Birks, John W; Salisbury, Dwayne; Carrion, Richard; Gates, Dan; Macias, Fabian; Rahn, Thom; Aiken, Allison C; Dubey, Manvendra K
| Idioma(s): Inglés
Understanding nitrogen oxides (NO = NO + NO ) measurement techniques is important as air-quality standards become more stringent, important sources change, and instrumentation develops. NO observations are compared in two environments: source testing from the combustion of Southwestern biomass fuels, and urban, ambient NO . The latter occurred in the urban core of Albuquerque, NM, at an EPA NCORE site during February-March 2017, a relatively clean photochemical environment with ozone (O ) <60 ppb for all but 6 hr. We compare two techniques used to measure NO in biomass smoke during biomass burning source testing: light absorption at 405 nm and a traditional chemiluminescence monitor. Two additional oxides of nitrogen techniques were added in urban measurements: a cavity attenuated phase shift instrument for direct NO , and the NO chemiluminescence instrument (conversion of NO to NO by molybdenum catalyst). We find agreement similar to laboratory standards for NO , NO , and NO comparing all four instruments (R > 0.97, slopes between 0.95 and 1.01, intercepts < 2 ppb for 1-hr averages) in the slowly varying ambient setting. Little evidence for significant interferences in NO measurements was observed in comparing techniques in late-winter urban Albuquerque. This was also confirmed by negligible NO contributions as measured with an NO instrument. For the rapidly varying (1-min) higher NO concentrations in biomass smoke source testing, larger variability characterized chemiluminescence and absorption instruments. Differences between the two instruments were both positive and negative and occurred for total NO , NO, and NO . Nonetheless, integrating the NO signals over an entire burn experiment and comparing 95 combustion experiments, showed little evidence for large systematic influences of possible interfering species biasing the methods. For concentrations of <2 ppm, a comparison of burn integrated NOx, NO , and NO yielded slopes of 0.94 to 0.96, R of 0.83 to 0.93, and intercepts of 8 to 25 ppb. We attribute the latter, at least in part, to significant noise particularly at low NO concentrations, resulting from short averaging times during highly dynamic lab burns. Discrepancies between instruments as indicated by the intercepts urge caution with oxides of nitrogen measurements at concentrations <50 ppb for rapidly changing conditions. Implications: Multiple NO measurement methods were employed to measure NO concentrations at an EPA NCORE site in Albuquerque, NM, and in smoke produced by the combustion of Southwestern biomass fuels. Agreement shown during intercomparison of these NO techniques indicated little evidence of significant interfering species biasing the methods in these two environments. Instrument agreement is important to understand for accurately characterizing ambient NO conditions in a range of environments.
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6.

Comparing risk environments for HIV among people who inject drugs from three cities in Northern Mexico.

Ospina-Escobar, Angelica; Magis-Rodríguez, Carlos; Juárez, Fatima; Werb, Dan; Bautista Arredondo, Sergio; Carreón, Rubén; Ramos, María Elena; Strathdee, Steffanie
| Idioma(s): Inglés
BACKGROUND: A large body of research has investigated the rise of injection drug use and HIV transmission in Tijuana and Ciudad Juarez (CJ). However, little is known about the dynamics of injecting in Hermosillo. This study compares drug-related behaviors and risk environment for HIV of people who inject drugs (PWID) across Tijuana, CJ, and Hermosillo to identify factors that could explain differences in HIV prevalence. METHODS: Data from Tijuana belong to a prospective study (El Cuete IV). Data from Hermosillo and Ciudad Juarez belong to a cross-sectional study. Both studies collected data in places where PWID spend time. All participants completed quantitative behavioral and serological testing for HIV. Datasets were merged using only comparable variables. Descriptive statistics tests were used to compare sociodemographic and behavioral characteristics of people who inject drugs PWID sampled in each city. A logistic regression model was built to identify factors independently associated with the likelihood of reporting receptive syringe sharing in the past 6 months. RESULTS: A total of 1494 PWID provided data between March 2011 and May 2012. HIV prevalence differed significantly between participants in Tijuana (4.2%), CJ (7.7%), and Hermosillo (5.2%; p < 0.05). PWID from Hermosillo reported better living conditions, less frequency of drug injection, and lower prevalence of syringe sharing (p < 0.01). PWID from CJ reported a higher prevalence of syringe sharing and confiscation by police (p < 0.01). In a multivariable logistic regression model, living in Hermosillo compared to Tijuana (adjusted odds ratio [AOR] = 0.42, 95% confidence interval [CI] 0.29-0.61) and being female (AOR = 0.61, 95% CI 0.45-0.83) were protective against syringe sharing. Having used crystal meth (AOR = 1.62, 95% CI 1.24-2.13, p = 0.001), having experienced syringe confiscation by police in the last 6 months (AOR = 1.78, 95% CI 1.34-2.40), and lower perception of syringe availability (AOR = 2.15, 95% CI 1.59-2.91) were significantly associated with syringe sharing (p < 0.05). CONCLUSIONS: Differences in HIV prevalence across cities reflect mainly differences in risk environments experienced by PWID, shaped by police practices, access to injection equipment, and dynamics of drug markets. Findings highlight the importance of ensuring sterile syringe availability through harm reduction services and a human rights approach to drug harms in northern Mexico and to generate better understanding of local dynamics and contexts of drug use for designing proper harm reduction programs.
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7.

The role of singing style in song adjustments to fluctuating sound conditions: A comparative study on Mexican birds.

Bermúdez-Cuamatzin, Eira; López-Hernández, Maricela; Campbell, James; Zuria, Iriana; Slabbekoorn, Hans
| Idioma(s): Inglés
Many bird species adjust their songs to noisy urban conditions by which they reduce masking and counteract the detrimental impact on signal efficiency. Different species vary in their response to level fluctuations of ambient noise, but it remains unclear why they vary. Here, we investigated whether noise-dependent flexibility may relate to singing style and signal function of the flexible acoustic trait. Species with highly variable songs may generally be more flexible and strongly repetitive singers may be more limited to stray from their stringent patterns. We exposed males of four passerine species with contrasting singing styles (repertoire size, immediate or eventual variety singing and syllable diversity) to three experimental sound conditions: 1) continuous urban noise; 2) intermittent white noise and 3) conspecific song playback. We found no spectral or temporal changes in response to experimental noise exposure in any of the four species, but significant temporal adjustment to conspecific playback in one of them. We argue that the consistency in song frequency and timing may have signal value, independent of singing style, and therefore be an explanation for the general lack of noise-dependent flexibility in the four species of the current study.
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8.

Implementación de un modelo de capacitación multimedial para brindar orientación alimentaria a los beneficiarios de un programa de ayuda social en México.

Amaya-Castellanos, Maritza Alejandra; Morales-Ruan, María Del Carmen; Uribe-Carvajal, Rebeca; Jiménez-Aguilar, Alejandra; Salazar-Coronel, Araceli Apolonia; Martínez-Tapia, Brenda; Shamah-Levy, Teresa
| Idioma(s): Inglés
Introducción: Se implementó un modelo de capacitación en orientación alimentaria para la población beneficiaria y el personal operativo del Programa de Abasto Rural (PAR) de Diconsa, el cual es una iniciativa social de ayuda alimentaria que abastece productos básicos y complementarios, además de brindar capacitación en localidades de alta marginación en México. Objetivo: Documentar la utilización de la Metodología de Capacitación Multimedial (MCM) en el desarrollo de un esquema de capacitación sobre orientación alimentaria y su implementación en la población beneficiaria del PAR, a través de la propia estructura operativa del PAR. Metodología: El modelo se fundamenta en la MCM, integrada por cuatro elementos didácticos e indivisibles que conforman el paquete pedagógico multimedial (PPM), compuesto a su vez por tres videos y rotafolios, material impreso, prácticas y las relaciones interpersonales. Los ejes temáticos fueron: alimentación correcta para una vida saludable, alimentación materno-infantil, elecciones saludables y gasto familiar. El modelo fue replicado en cascada en los tres niveles operativos del PAR (responsables de capacitación, supervisores operativos y beneficiarios del PAR), con un componente de multiplicación horizontal, e implementado como piloto en cuatro estados de México. Resultados: Se observó un cambio positivo sobre los conocimientos en alimentación correcta en todos los niveles de capacitación, principalmente en los beneficiarios del PAR. La evaluación del proceso mostró conocimientos previos de los responsables de capacitación en los temas, buen desempeño como facilitadores, y habilidades de presentación y manejo del grupo de los supervisores operativos. A partir de las evaluaciones y del acompañamiento en la prueba piloto, fueron modificados las actividades, las estrategias y los materiales educativos del PPM. Conclusiones: La capacitación multimedial y la educación nutricional promueven procesos de cambio y desarrollo comunitario, posibles a través de la toma de conciencia y la puesta en práctica de acciones que favorecen la salud.
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9.

Head stabilisation in fast running lizards.

Goyens, Jana; Aerts, Peter
| Idioma(s): Inglés
The cyclic patterns of terrestrial animal locomotion are frequently perturbed in natural environments. The terrain can be complex or inclined, the substrate can move unexpectedly and animals can misjudge situations. Loosing stability due to perturbations increases the probability of capture by predators and decreases the chance of successful prey capture and winning intraspecific battles. When controlled corrective actions are necessary to negotiate perturbations, animals rely on their exteroceptive and proprioceptive senses to monitor the environment and their own body movements. The vestibular system in the inner ear perceives linear and angular accelerations. This information enables gaze stabilisation and the creation of a stable, world-bound reference frame for the integration of the information of other senses. During locomotion, both functions are known to be facilitated by head stabilisation in several animals with an erect posture. Animals with a sprawled body posture, however, undergo very large body undulations while running. Using high speed video recordings, we tested whether they nevertheless stabilise their head during running, and how this is influenced by perturbations. We found that running Acanthodactylus boskianus lizards strongly stabilise their head yaw rotations when running on a flat, straight runway: the head rotation amplitude is only 4.76±0.99°, while the adjacent trunk part rotates over 27.0±3.8°. Lateral head translations are not stabilised (average amplitude of 7.4±2.0mm). When the lizards are experimentally perturbed by a large and unexpected lateral substrate movement, lateral translations of both the head and the body decrease (on average by 1.52±0.81mm). At the same time, the rotations of the head and trunk also decrease (on average by 1.62°±7.21°). These results show that head stabilisation intensifies because of the perturbation, which emphasises the importance of vestibular perception and balance in these fast and manoeuvrable animals.
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10.

Assessing the potential impacts of a changing climate on the distribution of a rabies virus vector.

Hayes, Mark A; Piaggio, Antoinette J
| Idioma(s): Inglés
Common vampire bats (Desmodus rotundus) occur throughout much of South America to northern México. Vampire bats have not been documented in recent history in the United States, but have been documented within about 50 km of the U.S. state of Texas. Vampire bats feed regularly on the blood of mammals and can transmit rabies virus to native species and livestock, causing impacts on the health of prey. Thus cattle producers, wildlife management agencies, and other stakeholders have expressed concerns about whether vampire bats might spread into the southern United States. On the other hand, concerns about vampire-borne rabies can also result in wanton destruction at bat roosts in areas occupied by vampire bats, but also in areas not known to be occupied by this species. This can in turn negatively affect some bat roosts, populations, and species that are of conservation concern, including vampire bats. To better understand the current and possible future distribution of vampire bats in North America and help mitigate future cattle management problems, we used 7,094 vampire bat occurrence records from North America and species distribution modeling (SDM) to map the potential distribution of vampire bats in North America under current and future climate change scenarios. We analysed and mapped the potential distribution of this species using 5 approaches to species distribution modeling: logistic regression, multivariate adaptive regression splines, boosted regression trees, random forest, and maximum entropy. We then projected these models into 17 "worst-case" future climate scenarios for year 2070 to generate hypotheses about how the vampire bat distribution in North America might change in the future. Of the variables used in this analysis, minimum temperature of the coldest month had the highest variable importance using all 5 SDM approaches. These results suggest two potential near-future routes of vampire bat dispersal into the U.S., one via southern Texas, and a second into southern Florida. Some of our SDM models support the hypothesis that suitable habitat for vampire bats may currently exist in parts of the México-U.S. borderlands, including extreme southern portions of Texas, as well as in southern Florida. However, this analysis also suggests that extensive expansion into the south-eastern and south-western U.S. over the coming ~60 years appears unlikely.
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