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On July 1st, 2018, federal elections for president, senators and deputies took place in Mexico. In most states, elections for state governors and representatives took also place in the same polling booths. The Technical Unit for Information Services (UNICOM) of the National Electoral Institute (INE) of Mexico has the responsibility for planning and implementation of the Preliminary Electoral Results Program (PREP) for federal elections. For the 2018 elections UNICOM developed forecasting models for the performance of PREP based on simulation models that were developed using a special purpose simulation software and C++ subroutines for fast simulation of queues. These simulation models were a valuable tool for planning, scheduling and allocation of the main resources that participated in the operational process of the PREP. In this article we report the main features, applications and results obtained by using these simulation models. [ABSTRACT FROM AUTHOR]

Stingless bees are the largest group of eusocial pollinators with diverse natural histories, including obligate cleptobionts (genus Lestrimelitta) that completely abandoned flower visitation to rely on other stingless bees for food and nest materials. Species of Lestrimeliita are thought to specialize upon different host species, and deception through chemical similarity has been proposed as a mechanism to explain this phenomenon. In the Yucatan Peninsula of Mexico, Scaptotrigona pectoralis is a species chemically distinct from, and not preferred as a host by, locally widespread Lestrimeliita niitkib; witnessing attacks on S. pectoralis colonies offered the opportunity to test the sensory deception hypothesis to cletoparasitism. Analysis of cuticular profiles revealed that the Lestrimelitta attacking S. pectoralis differed significantly in odour bouquet to L. niitkib and, in contrast, it resembled that of S. pectoralis. Further analyses, including morphometrics, mtDNA barcoding, and the examination of taxonomic features, confirmed the existence of two sympatric Lestrimelitta species. The results give support to the hypothesis of chemical deception as a cleptobiotic strategy in Lestrimelitta sp. This is the first evidence that sympatric cleptobionts of the same genus select hosts in accordance with species-specific cuticular profiles, with possible consequences for ecological adaptation and the evolution of these remarkable organisms and the community of stingless bee hosts. [ABSTRACT FROM AUTHOR]

A high impact of ARID5B SNPs on acute lymphoblastic leukemia (ALL) susceptibility has been described in Hispanic children; therefore, it is relevant to know if they influence the high incidence of childhood-ALL in Mexicans. Seven SNPs (rs10821936, rs10994982, rs7089424, rs2393732, rs2393782, rs2893881, rs4948488) of ARID5B were analyzed in 384 controls and 298 ALL children using genomic DNA and TaqMan probes. The SNPs were analyzed for deviation of Hardy-Weinberg equilibrium; Fisher's exact test was used to compare the genotypic and allelic frequencies between controls and patients. The association between SNPs and ALL susceptibility was calculated, and haplotype and ancestry analyses were conducted. All SNPs were associated with ALL, pre-B ALL, and hyperdiploid-ALL susceptibility (p < 0.05). No association with T-ALL and gene fusions was found (p > 0.05). The seven SNPs were associated with risk of pre-B ALL in younger children; however, rs2393732, rs2393782, rs2893881, and rs4948488 were not associated with susceptibility in older children and adolescents. The CAG haplotype (rs10821936, rs10994982, rs7089424) was strongly associated with ALL risk in our population (p < 0.00001). The frequency of all risk alleles in our ALL, pre-B, and hyperdiploid-ALL patients was higher than that in Hispanic children reported. This is the first report showing the association between rs2393732, rs2393782, and rs4948488 with pre-B hyperdiploid-ALL children. The G allele at rs2893881 confers major risk for pre-B hyperdiploid-ALL in Mexican (OR, 2.29) than in Hispanic children (OR, 1.71). The genetic background of our population could influence the susceptibility to ALL and explain its high incidence in Mexico. [ABSTRACT FROM AUTHOR]

This paper is about the development of a forecasting model that has been used in the Mexican Institute for Adult Education. This institute is in charge of an adult education program that is based on 42 modules, each of which requires books and materials each year. Accurate forecasts are needed to reduce the costs of wastage and shortages. Using data from previous years, the structure of the program, and interviews with officials in the Institute, we have developed a forecasting model based on Bayesian estimation. We further developed an approach that combines simulation with forecasting techniques, which may be appropriate when using a complex forecasting model. The initial results are encouraging, and we believe that the approach can be used in other situations, especially those concerned with service encounters. Our model also helps officials to understand several aspects of the education program. [ABSTRACT FROM AUTHOR]

The Instituto para el Depósito de Valores (INDEVAL) is the Central Securities Depository of Mexico. It is the only Mexican institution authorized to perform, in an integrated manner, the activities of safe-keeping, custody, management, clearing, settlement and transfer of securities. In this article, we report the modeling, simulation and analysis of a new Securities Settlement System (SSS) implemented by INDEVAL, as part of a project for the implementation of a safer and more efficient operating system. The main objective of this research was to use reduced amounts of cash and securities, within reasonable periods of time, for the settlement of securities of the Mexican market. A linear programming model for the netting and clearing of operations was used. The performance of the new SSS was evaluated by performing experiments using a deterministic simulation model under different operation parameters, such as the number and monetary value of transactions, the time between clearing cycles and also under a new set of rules for pre-settlement operations. The results presented may be used by other Central Securities Depositories to make decisions related to the efficient and safer use of their resources. The implementation of the model took more than three years. Now many transactions that would remain pending if processed individually are settled together, thus reducing liquidity requirements dramatically -by 52% in cash and 26% in securities. [ABSTRACT FROM AUTHOR]

INDEVAL, Mexico's central securities depository for all financial securities, implemented a new operating system to increase its operational efficiency and comply with international securities-settlement best practices. INDEVAL used operations research techniques in its core clearing process and in testing the new system's viability. Best practices address high capacity and reliability, real-time settlement, delivery versus payment (DvP), secure data storage and communications (based on the ISO15022 standard), central bank cash funds, and operational transparency. In this paper, we define the problem and discuss a linear programming model, system simulation, and major business process modeling that we devised for the new system. A novel application of operations research techniques provided several benefits, including (1) analysis and testing of the DvP settlement mechanism, which quickly and efficiently processes transactions and optimally uses available cash and securities balances; (2) a secure, reliable, and automatic clearing and settlement engine that operates continuously and efficiently handles all transactions that INDEVAL receives from its participants; and (3) an intelligent and flexible presettlement function that uses business rules and parameters to control the execution of the clearing and settlement process. The new system settles securities transactions that average over $250 billion daily; its successful implementation has substantially improved Mexico's financial system. [ABSTRACT FROM AUTHOR]

Background, aim, and scope This paper presents a waste management analysis of the packaging systems for soft drinks in Mexico, with emphasis on polyethylene terephthalate (PET) containers. The work presented is part of a project sponsored by a consortium of Mexican industries that participate in the PET market, such as resin producers, bottle manufacturers, soft drinks producers, distributors, and plastic recyclers. Two different life cycle assessments (LCAs) were elaborated to provide insight on waste management scenarios and waste products comparisons, respectively. The first LCA was a description of the actual PET market and PET waste treatment in Mexico. On the second LCA, three systems were analyzed: PET bottles, aluminum cans, and glass bottles. Currently, these results are used in Mexico as a basis for environmental policy. Materials and methods PET bottle's participation in the market has increased substantially in the previous years, and it is forecasted that this increase rate will continue. Due to this factor, there are some concerns about the environmental implications of PET usage. In order to analyze the waste management of PET bottles in Mexico, an LCA and a series of sensitivity analyses were conducted in order to understand: (1) the effect of different collecting distances in environmental impacts, (2) the effect of different recycling rates in environmental impacts, (3) the effect of different collecting rates in environmental impacts, and (4) the effect of different collecting rates with its associated distances in the environmental impacts. Results and conclusions An optimal degree of PET waste collection was identified as a result of considering different collecting rates and distances. At this point, minimum environmental impact occurs. This is due to the excessive increase in environmental resources that is needed in order to collect higher amounts of waste by traveling longer distances. These results may pose significant implications on current environmental legislation and waste management policies in Mexico and can well be applied into other Latin-American and developing countries. Other results show that production processes represent the highest environmental impacts along the supply chain, which are considerably higher than those impacts related to transport and collecting activities. Because of this, the environmental advantages of waste management in Mexico can be significant as long as the material that is collected is also recycled. Results to be presented include specific impact data on electricity generation and transport in Mexico. Recommendations and perspectives This work can be used as a basis for decision making in environmental policy. Moreover, it provides technical grounds to demonstrate that under certain conditions, traditional waste management systems may cause higher environmental impacts than the environmental benefit/credit that they are supposed to deliver. [ABSTRACT FROM AUTHOR]

Recent evidence indicates that primate populations may persist in neotropical fragmented landscapes by using arboreal agroecosystems, which may provide temporary habitats, increased areas of vegetation, and connectivity, among other benefits. However, limited data are available on how primates are able to sustain themselves in such manmade habitats. We report the results of a 9-month-long investigation of the feeding ecology of a troop of howler monkeys (n=24) that have lived for the past 25 years in a 12-ha cacao plantation in the lowlands of Tabasco, Mexico. A vegetation census indicated the presence of 630 trees (≥20 cm diameter at breast height (DBH)) of 32 shade species in the plantation. The howlers used 16 plant species (13 of which were trees) as sources of leaves, fruits, and flowers. Five shade tree species (Ficus cotinifolia, Pithecellobium saman, Gliricidia sepium, F. obtusifolia, and Ficus sp.) accounted for slightly over 80% of the total feeding time and 78% of the total number trees (n=139) used by the howlers, and were consistently used by the howlers from month to month. The howlers spent an average of 51% of their monthly feeding time exploiting young leaves, 29% exploiting mature fruit, and 20% exploiting flowers and other plant items. Monthly consumption of young leaves varied from 23% to 67%, and monthly consumption of ripe fruit varied from 12% to 64%. Differences in the protein-to-fiber ratio of young vs. mature leaves influenced diet selection by the monkeys. The howlers used 8.3 ha of the plantation area, and on average traveled 388 m per day in each month. The howlers preferred tree species whose contribution to the total tree biomass and density was above average for the shade-tree population in the plantation. Given the right conditions of management and protection, shaded arboreal plantations in fragmented landscapes can sustain segments of howler monkey populations for many decades. Am. J. Primatol. 68:127–142, 2006. © 2006 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Background: According to data from the World Health Organization and UNICEF from year 2009, iron deficiency is the most widespread nutritional deficiency worldwide. This deficiency causes an imbalance between needs and iron supply, which consequently results in anemia. Around the world, two million people suffer from anemia, half of which is due to iron deficiency. The most impacted groups are children and teenagers, due to their highest requirements derived from the growing process, and women in their reproductive age, due to their loss of iron derived from menstruating or to their highest iron needs during pregnancy. This increase in needs is not satisfied by the regular diet, since it includes an insufficient amount and/or low bioavailability of iron., Purpose: To share with the medical community treating pregnant women the experience of an expert group so that they always bear in mind the repercussions caused by anemia during pregnancy, know more about the diagnostic possibilities and have a reference point for prescribing iron supplements., Method: The consensus method was used through the expert panel group technique. Two rounds were taken for structuring the clinical questions. The first one was to facilitate working groups their focusing in the clinical topics and the population of interest; the second one was to aid in posing specific questions observing the Patient, Intervention, Compare and Outcome (PICO) structure. The primary and clinical secondary study variables were defined by the working groups from the previously developed questions and during the face-to-face working period, according to the natural history of the disease: risk factors, diagnostic classification, (either pharmacological or non pharmacological) treatment and prognosis. The level of evidence and clinical recommendation was classified based on the Evidence Classification Level and Clinical Recommendation of the Medicine Group based on Evidence from Oxford University., Results: In Mexico, 20.6% of pregnant women suffer from anemia, especially those between 15 and 16 years old, who prevail in 42.4% and 34.3% percent, respectively. Almost half the cases are due to iron deficiency. This type of anemia is associated with a higher risk of pre-term delivery, of low birth weight and perinatal death. The first assessment of an anemic pregnant woman shall include the medical history, a physical examination and the quantification of the erythrocyte indices, serum concentrations of iron and ferritin. The measurement of this last one has the highest sensitivity and specificity for diagnosing iron deficiency. Daily oral iron supplementation, at a 60-to-120 mg dosage, may correct most of mild-to-moderate anemias. The most appropriate treatment is with iron salts (iron sulfate, polimaltose iron complex or iron fumarate). In case of intolerance to iron sulfate or fumarate, polimaltose iron is a better tolerated option. Treatment shall be administered until the hemoglobin values are > 10.5 g and ferritin is between 300 and 360 microg/dL, and such levels shall be observed for at least one year. Parenteral administration is an alternative for patients with a severe intolerance to oral administration; even when the possibility of anaphylaxis shall be considered it is lower when using ferrous sacarate. Transfusion is reserved for patients with hemoglobin lower than 7 g/dL or having an imminent cardio-respiratory decompensation., Conclusions: Iron deficiency is the highest prevailing nutritional deficiency worldwide and its consequences during pregnancy may be highly risky for both the mother and her child. Anemia diagnosis may easily be achieved through a blood analysis including the serum ferritin determination. Serum iron measurement shall not be used as the only marker to set the diagnosis. It is important to rule out other causes, in addition to the deficiencies, which produce anemia in a patient. It is essential to suggest the administration of iron supplements not only during the antenatal period but also after birth o even after a miscarriage to fulfill the need for depleted iron. In severe anemias (hemoglobin being lower than 9.0 g/L), iron doses higher than 120 mg a day may be required. Treatment shall always begin orally, and if this is not well tolerated, parenteral administration shall be used.

Little is known about the population characteristics of Alouatta pigra under conditions of forest fragmentation-information that is important to understanding its tolerance to habitat loss. In this work we present data on forest loss and on troop size, age, and sex composition for a population of black howler monkeys existing in the fragmented landscape surrounding the Mayan site of Palenque, Chiapas, Mexico. Two aerial photos (1:70,000) of the study area (261 km(2)) taken in 1984 and 2001 were examined to assess forest loss. Between June and December 2001 and January and March 2002 we surveyed 44 forest fragments for the presence of howler monkeys. Examination of aerial photos showed that 33% of the forest present in 1984 had disappeared by 2001, and detected an increment in the number of forest fragments present in the landscape. We discovered a total of 115 howler monkeys living in 22 of the 44 forest fragments studied, of which 107 were members of 18 troops. The rest were solitary males or small groups of males living in isolated forest fragments. Troop size ranged from two to 15 individuals (mean 5.9+3.0 ind). 31% and 15% of individuals in the troops were juveniles and infants, respectively, suggesting continued reproductive activity. Howler monkey troops in the forest fragments were on average smaller (5.9+/-3.0 ind) than troops in the nearby protected forest of the Mayan site (7.0+/-2.8 ind). The mean density of howlers in the forest fragments was 119+/-82.9 ind/km(2). The establishment of corridors is suggested as a possible conservation scenario for the fragmented howler population investigated, and as a conservation measure to connect this population with the howler population found in the protected forest of the Mayan site., (Copyright 2002 Wiley-Liss, Inc.)