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Several studies have shown that the performance of a supply chain is heavily influenced by the pattern of relationships among firms. This paper analyzes the structure of relationships (network topology) that leads to the highest agility of a food supply chain when sudden demand changes occur. To do this, a simulation model that represents a supply chain and specific rules to allocate orders is built. The supply chain in the model follows the specific characteristics of trade in the primary sector. The model is fitted to the conditions of a real seafood supply chain in Mexico. Agility is measured through the effect on the order fulfillment of a sudden demand shock and the recovery time of this rate to previous values. The simulation results show that the most suitable structure depends on how product is distributed among suppliers. If product is evenly shared, supply chains with homogeneous topologies are more agile than supply chains with heterogeneous topologies, but the result is the opposite if product is unevenly shared among suppliers. Other previous recommendations, such as having multiple suppliers and horizontal links, are confirmed by the simulations. These findings contribute to the general debate on which is the optimal topology for an agile supply chain. [ABSTRACT FROM AUTHOR]

To document the diversity and distribution of mosquitoes inhabiting the Mexican state of Nuevo León, collection trips were conducted to all physiographic regions (Grand Northamerican Plains, Coastal Plain of North Gulf, and Sierra Madre Oriental) and subregions across the state. A total of 3,176 specimens were collected. Additionally, we re-examined mosquito specimens in two Mexican entomological collections: The Collection of Insects and Mites of Medical Importance and the Collection of Arthropods of Medical Importance. These represent the two culicid subfamilies Anophelinae and Culicinae, 8 tribes, 12 genera, 25 subgenera, and 64 named species. Of these, 1 tribe, 2 genera, 5 subgenera, and 14 species are new records for the mosquito fauna of Nuevo León. Three undescribed species were collected. Two are described in this study: Aedes (Ochlerotatus) amateuri Ortega & Zavortink n. sp., and Aedes (Protomacleaya) lewnielseni Ortega & Zavortink n. sp. The third belongs to the genus Wyeomyia. Twelve species previously recorded from Nuevo León were not collected during this study. Taxonomic notes, new distribution limits, and comments about the medical importance of some species are reported. [ABSTRACT FROM AUTHOR]

This study explores the way in which traveling paths in ancient cultures are characterized by the relationship between nonlinear shapes and path lengths in terms of distances. In particular, we analyze the case of trade routes that connected Aztec settlements around 1521 CE in central Mexico. Based on the complex systems perspective, we used the least cost path approximation to reconstruct a hypothetical large-scale map of routes reproducing physical connections among ancient places. We compared these connections with different spatial configurations and identified the probability distribution functions of path lengths. We evaluated the nonlinearity using the mean absolute error based on the path fitness of simple linear models. We found asymmetrical distributions and positive relationships between those measures. If a path length increases, so does its nonlinearity. Thus, the simple pattern of traveling in the Aztec region is fairly unlikely to be straight and short. Complex pathways can represent most of the ancient routes in central Mexico. [ABSTRACT FROM AUTHOR]

Background: Evidence highlights a global shortage of wheelchair service provision education and training that results in inappropriate wheelchair provision with associated health and economic consequences. Two learning methodologies, a hybrid and an in-person course, based on the World Health Organization Wheelchair Service Training Package Basic Level, currently are available to train wheelchair service providers worldwide. The effectiveness of the in-person methodology, used as the standard of practice, has never been tested. Meanwhile, the Hybrid Course, which combines online and in-person training, was developed to reduce training costs and to scale training interventions and has shown potential effectiveness in increasing basic level wheelchair service provision knowledge. The objective of this study was to compare the effectiveness of both learning methodologies based on knowledge and satisfaction among a group of wheelchair service providers in India and Mexico. Methods: We conducted a controlled quasi-experimental study to evaluate changes in basic wheelchair knowledge and levels of satisfaction between Hybrid and In-person course learners in India and Mexico. A convenience sampling method guided by local stakeholders’ input was used to recruit participants. Outcomes were assessed using self-administered online surveys, the International Society of Wheelchair Professionals Wheelchair Service Provision Basic Test (primary outcome) completed pre- and post- the learning intervention and an anonymous Satisfaction Survey (secondary outcome) completed post- intervention. Baseline characteristics were compared among groups using hypothesis tests based on their assumptions. The primary analysis was intention-to-treat. To address missing values and lost to follow-up, multiple chained imputations were conducted. The primary outcome was analyzed using linear mixed models. The secondary outcome was analyzed using a two-tailed two independent samples t-test. Results: A total of 81 participants, 43 (53.1%) in the In-person group and 38 (46.9%) in the Hybrid group, participated in the study. Mean baseline knowledge scores were below the passing cutoff of the test (53 points) in both groups. Both study groups experienced statistically significant improvements in the primary outcome when comparing pre- and post-test scores (p<0.0001) with total mean scores above the passing cutoff of the test. The in-person group experienced, on average, larger effects on the primary outcome. The difference in mean change from post-test to pre-tests between In-person groups and Hybrid was 3.6 (95% Confidence Interval: 1.7;5.4), Cohen’s d = 0.36, with a small effect size favoring the In-person training. With regards to satisfaction, the difference between the two interventions was 0.23±0.07 in favor of the In-person group (p = 0.0021). Conclusions: Both learning methodologies had a statistically significant effect in increasing wheelchair service knowledge with overall high levels of satisfaction. However, the In-person group reported overall larger effects when compared with the Hybrid methodology. This study provided recommendations on how organizations can improve blended learning interventions to enhance participants’ learning experiences and reduce potential barriers and limitations. [ABSTRACT FROM AUTHOR]

Objective: To identify socio-demographic factors associated with presenting for abortion services past the gestational age (GA) limit (12 weeks), and thus not receiving services, in Mexico City’s public sector first trimester abortion program. Methods: We used clinical data from four high volume sites in the Interrupción Legal de Embarazo (ILE) program, 2007–2015. We used descriptive statistics to quantify the proportion of women who did not receive an abortion due to presenting past the gestational age limit. We used multivariable logistic regression to identify associations between women’s characteristics and presenting past the GA limit and calculated predicted probabilities of late presentation for key characteristics. Results: Our sample included 52,391 women, 8.10% (n = 4,246) of whom did not receive abortion services due to presenting past the GA limit. Adolescents (12–17) made up 8.69% of the total sample and 13.40% of those presenting past the GA limit (p< 0.05). In multivariable analyses, all age groups of adult women had significantly lower odds than adolescents of presenting past the limit (aOR = 0.77, aOR = 0.63, aOR = 0.58 and aOR = 0.37 for 19–24, 25–29, 30–39, and > = 40 years’ old respectively). Women living in Mexico City and with higher levels of education had lower odds of presenting past the GA limit, and there was an educational gradient across all age groups. In the multivariable predicted probability models, adolescents at every level of education have significantly higher probabilities of not receiving an abortion due to presenting past the gestational age limit compared with adults (among women with a primary education: 11.75% adolescents vs. 9.02–4.26% across adult age groups). Conclusions: Our results suggest that continued efforts are needed to educate women, especially younger and less educated women, about early pregnancy recognition. In addition, all women need information about the availability of first trimester legal abortion to ensure timely access to abortion services. [ABSTRACT FROM AUTHOR]

Cattle ticks are distributed worldwide and affect animal health and livestock production. White tailed deer (WTD) sustain and spread cattle tick populations. The aim of this study was to model the efficacy of anti-tick vaccination of WTD to control tick infestations in the absence of cattle vaccination in a territory where both host species coexist and sustain cattle tick populations. Agent-based models that included land cover/landscape properties (patch size, distances to patches) and climatic conditions were built in a GIS environment to simulate WTD vaccine effectiveness under conditions where unvaccinated cattle shared the landscape. Published and validated information on tick life cycle was used to build models describing tick mortality and developmental rates. Data from simulations were applied to a large territory in northeastern Mexico where cattle ticks are endemic and WTD and cattle share substantial portions of the habitat. WTD movements were simulated together with tick population dynamics considering the actual landscape and climatic features. The size of the vegetation patches and the distance between patches were critical for the successful control of tick infestations after WTD vaccination. The presence of well-connected, large vegetation patches proved essential for tick control, since the tick could persist in areas of highly fragmented habitat. The continued application of one yearly vaccination on days 1-70 for three years reduced tick abundance/animal/patch by a factor of 40 and 60 for R. annulatus and R. microplus, respectively when compared to non-vaccinated controls. The study showed that vaccination of WTD alone during three consecutive years could result in the reduction of cattle tick populations in northeastern Mexico. Furthermore, the results of the simulations suggested the possibility of using vaccines to prevent the spread and thus the re-introduction of cattle ticks into tick-free areas. [ABSTRACT FROM AUTHOR]